[Title 40 CFR ]
[Code of Federal Regulations (annual edition) - July 1, 2018 Edition]
[From the U.S. Government Publishing Office]
[[Page i]]
Title 40
Protection of Environment
________________________
Parts 136 to 149
Revised as of July 1, 2018
Containing a codification of documents of general
applicability and future effect
As of July 1, 2018
Published by the Office of the Federal Register
National Archives and Records Administration as a
Special Edition of the Federal Register
[[Page ii]]
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[[Page iii]]
Table of Contents
Page
Explanation................................................. v
Title 40:
Chapter I--Environmental Protection Agency
(Continued) 3
Finding Aids:
Table of CFR Titles and Chapters........................ 1059
Alphabetical List of Agencies Appearing in the CFR...... 1079
List of CFR Sections Affected........................... 1089
[[Page iv]]
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Cite this Code: CFR
To cite the regulations in
this volume use title,
part and section number.
Thus, 40 CFR 136.1 refers
to title 40, part 136,
section 1.
----------------------------
[[Page v]]
EXPLANATION
The Code of Federal Regulations is a codification of the general and
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Each volume of the Code is revised at least once each calendar year
and issued on a quarterly basis approximately as follows:
Title 1 through Title 16.................................as of January 1
Title 17 through Title 27..................................as of April 1
Title 28 through Title 41...................................as of July 1
Title 42 through Title 50................................as of October 1
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[[Page vi]]
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[[Page vii]]
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July 1, 2018
[[Page ix]]
THIS TITLE
Title 40--Protection of Environment is composed of thirty-seven
volumes. The parts in these volumes are arranged in the following order:
Parts 1-49, parts 50-51, part 52 (52.01-52.1018), part 52 (52.1019-
52.2019), part 52 (52.2020-end of part 52), parts 53-59, part 60 (60.1-
60.499) , part 60 (60.500-end of part 60, sections), part 60
(Appendices), parts 61-62, part 63 (63.1-63.599), part 63 (63.600-
63.1199), part 63 (63.1200-63.1439), part 63 (63.1440-63.6175), part 63
(63.6580-63.8830), part 63 (63.8980-end of part 63), parts 64-71, parts
72-79, part 80, part 81, parts 82-86, parts 87-95, parts 96-99, parts
100-135, parts 136-149, parts 150-189, parts 190-259, parts 260-265,
parts 266-299, parts 300-399, parts 400-424, parts 425-699, parts 700-
722, parts 723-789, parts 790-999, parts 1000-1059, and part 1060 to
end. The contents of these volumes represent all current regulations
codified under this title of the CFR as of July 1, 2018.
Chapter I--Environmental Protection Agency appears in all thirty-
seven volumes. Regulations issued by the Council on Environmental
Quality, including an Index to Parts 1500 through 1508, appear in the
volume containing parts 1060 to end. The OMB control numbers for title
40 appear in Sec. 9.1 of this chapter.
For this volume, Cheryl E. Sirofchuck was Chief Editor. The Code of
Federal Regulations publication program is under the direction of John
Hyrum Martinez, assisted by Stephen J. Frattini.
[[Page 1]]
TITLE 40--PROTECTION OF ENVIRONMENT
(This book contains parts 136 to 149)
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Part
chapter i--Environmental Protection Agency (Continued)...... 136
[[Page 3]]
CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
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Editorial Note: Nomenclature changes to chapter I appear at 65 FR
47324, 47325, Aug. 2, 2000, and at 66 FR 34375, 34376, June 28, 2001.
SUBCHAPTER D--WATER PROGRAMS (CONTINUED)
Part Page
136 Guidelines establishing test procedures for
the analysis of pollutants.............. 5
140 Marine sanitation device standard........... 420
141 National primary drinking water regulations. 424
142 National primary drinking water regulations
implementation.......................... 735
143 National secondary drinking water
regulations............................. 795
144 Underground injection control program....... 800
145 State UIC program requirements.............. 869
146 Underground injection control program:
Criteria and standards.................. 882
147 State, tribal, and EPA-administered
underground injection control programs.. 935
148 Hazardous waste injection restrictions...... 1042
149 Sole source aquifers........................ 1051
[[Page 5]]
SUBCHAPTER D_WATER PROGRAMS (CONTINUED)
PART 136_GUIDELINES ESTABLISHING TEST PROCEDURES FOR THE ANALYSIS
OF POLLUTANTS--Table of Contents
Sec.
136.1 Applicability.
136.2 Definitions.
136.3 Identification of test procedures.
136.4 Application for and approval of alternate test procedures for
nationwide use.
136.5 Approval of alternate test procedures for limited use.
136.6 Method modifications and analytical requirements.
136.7 Quality assurance and quality control.
Appendix A to Part 136--Methods for Organic Chemical Analysis of
Municipal and Industrial Wastewater
Appendix B to Part 136--Definition and Procedure for the Determination
of the Method Detection Limit--Revision 1.11
Appendix C to Part 136--Determination of Metals and Trace Elements in
Water and Wastes by Inductively Coupled Plasma-Atomic Emission
Spectrometry Method 200.7
Appendix D to Part 136--Precision and Recovery Statements for Methods
for Measuring Metals
Authority: Secs. 301, 304(h), 307 and 501(a), Pub. L. 95-217, 91
Stat. 1566, et seq. (33 U.S.C. 1251, et seq.) (the Federal Water
Pollution Control Act Amendments of 1972 as amended by the Clean Water
Act of 1977).
Sec. 136.1 Applicability.
(a) The procedures prescribed herein shall, except as noted in
Sec. Sec. 136.4, 136.5, and 136.6, be used to perform the measurements
indicated whenever the waste constituent specified is required to be
measured for:
(1) An application submitted to the Director and/or reports required
to be submitted under NPDES permits or other requests for quantitative
or qualitative effluent data under parts 122 through 125 of this
chapter; and
(2) Reports required to be submitted by dischargers under the NPDES
established by parts 124 and 125 of this chapter; and
(3) Certifications issued by States pursuant to section 401 of the
Clean Water Act (CWA), as amended.
(b) The procedure prescribed herein and in part 503 of title 40
shall be used to perform the measurements required for an application
submitted to the Administrator or to a State for a sewage sludge permit
under section 405(f) of the Clean Water Act and for recordkeeping and
reporting requirements under part 503 of title 40.
(c) For the purposes of the NPDES program, when more than one test
procedure is approved under this part for the analysis of a pollutant or
pollutant parameter, the test procedure must be sufficiently sensitive
as defined at 40 CFR 122.21(e)(3) and 122.44(i)(1)(iv).
[72 FR 14224, Mar. 26, 2007, as amended at 77 FR 29771, May 18, 2012; 79
FR 49013, Aug. 19, 2014; 82 FR 40846, Aug. 28, 2017]
Sec. 136.2 Definitions.
As used in this part, the term:
(a) Act means the Clean Water Act of 1977, Pub. L. 95-217, 91 Stat.
1566, et seq. (33 U.S.C. 1251 et seq.) (The Federal Water Pollution
Control Act Amendments of 1972 as amended by the Clean Water Act of
1977).
(b) Administrator means the Administrator of the U.S. Environmental
Protection Agency.
(c) Regional Administrator means one of the EPA Regional
Administrators.
(d) Director means the director as defined in 40 CFR 122.2.
(e) National Pollutant Discharge Elimination System (NPDES) means
the national system for the issuance of permits under section 402 of the
Act and includes any State or interstate program which has been approved
by the Administrator, in whole or in part, pursuant to section 402 of
the Act.
(f) Detection limit means the minimum concentration of an analyte
(substance) that can be measured and reported with a 99% confidence that
the analyte concentration is distinguishable from the method blank
results as determined by the procedure set forth at appendix B of this
part.
[38 FR 28758, Oct. 16, 1973, as amended at 49 FR 43250, Oct. 26, 1984;
82 FR 40846, Aug. 28, 2017]
[[Page 6]]
Sec. 136.3 Identification of test procedures.
(a) Parameters or pollutants, for which methods are approved, are
listed together with test procedure descriptions and references in
Tables IA, IB, IC, ID, IE, IF, IG, and IH of this section. The methods
listed in Tables IA, IB, IC, ID, IE, IF, IG, and IH are incorporated by
reference, see paragraph (b) of this section, with the exception of EPA
Methods 200.7, 601-613, 624.1, 625.1, 1613, 1624, and 1625. The full
texts of Methods 601-613, 624.1, 625.1, 1613, 1624, and 1625 are printed
in appendix A of this part, and the full text of Method 200.7 is printed
in appendix C of this part. The full text for determining the method
detection limit when using the test procedures is given in appendix B of
this part. In the event of a conflict between the reporting requirements
of 40 CFR parts 122 and 125 and any reporting requirements associated
with the methods listed in these tables, the provisions of 40 CFR parts
122 and 125 are controlling and will determine a permittee's reporting
requirements. The full texts of the referenced test procedures are
incorporated by reference into Tables IA, IB, IC, ID, IE, IF, IG, and
IH. The year after the method number indicates the latest editorial
change of the method. The discharge parameter values for which reports
are required must be determined by one of the standard analytical test
procedures incorporated by reference and described in Tables IA, IB, IC,
ID, IE, IF, IG, and IH or by any alternate test procedure which has been
approved by the Administrator under the provisions of paragraph (d) of
this section and Sec. Sec. 136.4 and 136.5. Under certain circumstances
(paragraph (c) of this section, in Sec. 136.5(a) through (d) or 40 CFR
401.13) other additional or alternate test procedures may be used.
[[Page 7]]
Table IA--List of Approved Biological Methods for Wastewater and Sewage Sludge
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Parameter and units Method \1\ EPA Standard methods AOAC, ASTM, USGS Other
--------------------------------------------------------------------------------------------------------------------------------------------------------
Bacteria
--------------------------------------------------------------------------------------------------------------------------------------------------------
1. Coliform (fecal), number per 100 Most Probable Number p. 132,\3\ 1680,11 15 9221 C E-2006........
mL or number per gram dry weight. (MPN), 5 tube, 3 1681 11 20.
dilution, or.
Multiple tube/multiple ...................... ..................... ..................... Colilert-18[supreg]13
well, or. 18 21 29.
Membrane filter (MF) p. 124 \3\............ 9222 D-2006 \30\..... B-0050-85 \4\........
\2\, single step.
2. Coliform (fecal) in presence of MPN, 5 tube, 3 p. 132 \3\............ 9221 C E-2006........
chlorine, number per 100 mL. dilution, or.
MF \2\, single step p. 124 \3\............ 9222 D-2006 \30\.....
\5\.
3. Coliform (total), number per 100 MPN, 5 tube, 3 p. 114 \3\............ 9221 B-2006..........
mL. dilution, or.
MF \2\, single step or p. 108 \3\............ 9222 B-2006.......... B-0025-85 \4\........
two step.
4. Coliform (total), in presence of MPN, 5 tube, 3 p. 114 \3\............ 9221 B-2006..........
chlorine, number per 100 mL. dilution, or.
MF \2\ with enrichment p. 111 \3\............ 9222 B-2006..........
\5\.
5. E. coli, number per 100 mL \21\. MPN 6 8 16 multiple ...................... 9221B.2-2006/9221F-
tube, or. 2006 12 14.
multiple tube/multiple ...................... 9223 B-2004 \13\..... 991.15 \10\.......... Colilert[supreg] 13
well, or. 18.
Colilert-18[supreg]
13 17 18
MF 2 6 7 8 single step 1603 \22\............. ..................... ..................... mColiBlue-
24[supreg]\19\.
6. Fecal streptococci, number per MPN, 5 tube, 3 p. 139 \3\............ 9230 B-2007..........
100 mL. dilution, or.
MF \2\, or............ p. 136 \3\............ 9230 C-2007.......... B-0055-85 \4\........
Plate count........... p. 143 \3\............
7. Enterococci, number per 100 mL MPN, 5 tube, 3 p. 139 \3\............ 9230 B-2007..........
\21\. dilution, or.
MPN 6 8, multiple tube/ ...................... 9230 D-2007.......... D6503-99 \9\......... Enterolert[supreg] 13
multiple well, or. 24.
MF 2 6 7 8 single step 1600 \25\............. 9230 C-2007..........
or.
Plate count........... p. 143 \3\............
[[Page 8]]
8.Salmonella number per gram dry MPN multiple tube..... 1682 \23\.............
weight \11\.
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Aquatic Toxicity
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9. Toxicity, acute, fresh water Ceriodaphnia dubia 2002.0 \26\...........
organisms, LC50, percent effluent. acute.
Daphnia puplex and 2021.0 \26\...........
Daphnia magna acute.
Fathead Minnow, 2000.0 \26\...........
Pimephales promelas,
and Bannerfin shiner,
Cyprinella leedsi,
acute.
Rainbow Trout, 2019.0 \26\...........
Oncorhynchus mykiss,
and brook trout,
Salvelinus
fontinalis, acute.
10. Toxicity, acute, estuarine and Mysid, Mysidopsis 2007.0 \26\...........
marine organisms of the Atlantic bahia, acute.
Ocean and Gulf of Mexico, LC50,
percent effluent.
Sheepshead Minnow, 2004.0 \26\...........
Cyprinodon
variegatus, acute.
Silverside, Menidia 2006.0 \26\...........
beryllina, Menidia
menidia, and Menidia
peninsulae, acute.
11. Toxicity, chronic, fresh water Fathead minnow, 1000.0 \27\...........
organisms, NOEC or IC25, percent Pimephales promelas,
effluent. larval survival and
growth.
[[Page 9]]
Fathead minnow, 1001.0 \27\...........
Pimephales promelas,
embryo-larval
survival and
teratogenicity.
Daphnia, Ceriodaphnia 1002.0 \27\...........
dubia, survival and
reproduction.
Green alga, 1003.0 \27\...........
Selenastrum
capricornutum, growth.
12. Toxicity, chronic, estuarine Sheepshead minnow, 1004.0 \28\...........
and marine organisms of the Cyprinodon
Atlantic Ocean and Gulf of Mexico, variegatus, larval
NOEC or IC25, percent effluent. survival and growth.
Sheepshead minnow, 1005.0 \28\...........
Cyprinodon
variegatus, embryo-
larval survival and
teratogenicity.
Inland silverside, 1006.0 \28\...........
Menidia beryllina,
larval survival and
growth.
Mysid, Mysidopsis 1007.0 \28\...........
bahia, survival,
growth, and fecundity.
Sea urchin, Arbacia 1008.0 \28\...........
punctulata,
fertilization.
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Table IA notes:
\1\ The method must be specified when results are reported.
\2\ A 0.45-[micro]m membrane filter (MF) or other pore size certified by the manufacturer to fully retain organisms to be cultivated and to be free of
extractables which could interfere with their growth.
\3\ Microbiological Methods for Monitoring the Environment, Water, and Wastes, EPA/600/8-78/017. 1978. U.S. EPA.
\4\ U.S. Geological Survey Techniques of Water-Resource Investigations, Book 5, Laboratory Analysis, Chapter A4, Methods for Collection and Analysis of
Aquatic Biological and Microbiological Samples. 1989. USGS.
\5\ Because the MF technique usually yields low and variable recovery from chlorinated wastewaters, the Most Probable Number method will be required to
resolve any controversies.
[[Page 10]]
\6\ Tests must be conducted to provide organism enumeration (density). Select the appropriate configuration of tubes/filtrations and dilutions/volumes
to account for the quality, character, consistency, and anticipated organism density of the water sample.
\7\ When the MF method has been used previously to test waters with high turbidity, large numbers of noncoliform bacteria, or samples that may contain
organisms stressed by chlorine, a parallel test should be conducted with a multiple-tube technique to demonstrate applicability and comparability of
results.
\8\ To assess the comparability of results obtained with individual methods, it is suggested that side-by-side tests be conducted across seasons of the
year with the water samples routinely tested in accordance with the most current Standard Methods for the Examination of Water and Wastewater or EPA
alternate test procedure (ATP) guidelines.
\9\ Annual Book of ASTM Standards-Water and Environmental Technology, Section 11.02. 2000, 1999, 1996. ASTM International.
\10\ Official Methods of Analysis of AOAC International. 16th Edition, 4th Revision, 1998. AOAC International.
\11\ Approved for enumeration of target organism in sewage sludge.
\12\ The multiple-tube fermentation test is used in 9221B.2-2006. Lactose broth may be used in lieu of lauryl tryptose broth (LTB), if at least 25
parallel tests are conducted between this broth and LTB using the water samples normally tested, and this comparison demonstrates that the false-
positive rate and false-negative rate for total coliform using lactose broth is less than 10 percent. No requirement exists to run the completed phase
on 10 percent of all total coliform-positive tubes on a seasonal basis.
\13\ These tests are collectively known as defined enzyme substrate tests, where, for example, a substrate is used to detect the enzyme [beta]-
glucuronidase produced by E. coli.
\14\ After prior enrichment in a presumptive medium for total coliform using 9221B.2-2006, all presumptive tubes or bottles showing any amount of gas,
growth or acidity within 48 h 3 h of incubation shall be submitted to 9221F-2006. Commercially available EC-MUG media or EC
media supplemented in the laboratory with 50 [micro]g/mL of MUG may be used.
\15\ Method 1680: Fecal Coliforms in Sewage Sludge (Biosolids) by Multiple-Tube Fermentation Using Lauryl-Tryptose Broth (LTB) and EC Medium, EPA-821-R-
14-009. September 2014. U.S. EPA.
\16\ Samples shall be enumerated by the multiple-tube or multiple-well procedure. Using multiple-tube procedures, employ an appropriate tube and
dilution configuration of the sample as needed and report the Most Probable Number (MPN). Samples tested with Colilert[supreg] may be enumerated with
the multiple-well procedures, Quanti-Tray[supreg] and the MPN calculated from the table provided by the manufacturer.
\17\ Colilert-18[supreg] is an optimized formulation of the Colilert[supreg] for the determination of total coliforms and E. coli that provides results
within 18 h of incubation at 35 [deg]C rather than the 24 h required for the Colilert[supreg] test and is recommended for marine water samples.
\18\ Descriptions of the Colilert[supreg], Colilert-18[supreg], and Quanti-Tray[supreg] may be obtained from IDEXX Laboratories, Inc.
\19\ A description of the mColiBlue24[supreg] test, is available from Hach Company.
\20\ Method 1681: Fecal Coliforms in Sewage Sludge (Biosolids) by Multiple-Tube Fermentation using A-1 Medium, EPA-821-R-06-013. July 2006. U.S. EPA.
\21\ Approved for enumeration of target organism in wastewater effluent.
\22\ Method 1603: Escherichia coli (E. coli) in Water by Membrane Filtration Using Modified membrane-Thermotolerant Escherichia coli Agar (modified
mTEC), EPA-821-R-14-010. September 2014. U.S. EPA.
\23\ Method 1682: Salmonella in Sewage Sludge (Biosolids) by Modified Semisolid Rappaport-Vassiliadis (MSRV) Medium, EPA-821-R-14-012. September 2014.
U.S. EPA.
\24\ A description of the Enterolert[supreg] test may be obtained from IDEXX Laboratories Inc.
\25\ Method 1600: Enterococci in Water by Membrane Filtration Using membrane-Enterococcus Indoxyl-[beta]-D-Glucoside Agar (mEI), EPA-821-R-14-011.
September 2014. U.S. EPA.
\26\ Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, EPA-821-R-02-012. Fifth Edition,
October 2002. U.S. EPA.
\27\ Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms, EPA-821-R-02-013. Fourth Edition,
October 2002. U.S. EPA.
\28\ Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and Estuarine Organisms, EPA-821-R-02-014. Third
Edition, October 2002. U.S. EPA.
\29\ To use Colilert-18[supreg] to assay for fecal coliforms, the incubation temperature is 44.5 0.2 [deg]C, and a water bath
incubator is used.
\30\ On a monthly basis, at least ten blue colonies from the medium must be verified using Lauryl Tryptose Broth and EC broth, followed by count
adjustment based on these results; and representative non-blue colonies should be verified using Lauryl Tryptose Broth. Where possible, verifications
should be done from randomized sample sources.
[[Page 11]]
Table IB--List of Approved Inorganic Test Procedures
--------------------------------------------------------------------------------------------------------------------------------------------------------
Parameter Methodology \58\ EPA \52\ Standard methods ASTM USGS/AOAC/other
--------------------------------------------------------------------------------------------------------------------------------------------------------
1. Acidity, as CaCO3, mg/L......... Electrometric endpoint ...................... 2310 B-2011.......... D1067-11............. I-1020-85.\2\
or phenolphthalein
endpoint.
2. Alkalinity, as CaCO3, mg/L...... Electrometric or ...................... 2320 B-2011.......... D1067-11............. 973.43,\3\ I-1030-
Colorimetric 85.\2\
titration to pH 4.5,
Manual.
Automatic............. 310.2 (Rev. 1974) \1\. ..................... ..................... I-2030-85.\2\
3. Aluminum--Total,\4\ mg/L........ Digestion,\4\ followed
by any of the
following:
AA direct aspiration ...................... 3111 D-2011 or 3111 E- ..................... I-3051-85.\2\
\36\. 2011.
AA furnace............ ...................... 3113 B-2010.
STGFAA................ 200.9, Rev. 2.2 (1994)
ICP/AES \36\.......... 200.5, Rev 4.2 (2003); 3120 B-2011.......... D1976-12............. I-4471-97.\50\
\68\ 200.7, Rev. 4.4
(1994).
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14,\3\ I-4471-
97.\50\
Direct Current Plasma ...................... ..................... D4190-08............. See footnote.\34\
(DCP) \36\.
Colorimetric ...................... 3500-Al B-2011.......
(Eriochrome cyanine
R).
4. Ammonia (as N), mg/L............ Manual distillation 350.1, Rev. 2.0 (1993) 4500-NH3 B-2011...... ..................... 973.49.\3\
\6\ or gas diffusion
(pH 11),
followed by any of
the following:.
Nesslerization........ ...................... ..................... D1426-08 (A)......... 973.49,\3\ I-3520-
85.\2\
Titration............. ...................... 4500-NH3 C-2011......
Electrode............. ...................... 4500-NH3 D-2011 or E- D1426-08 (B).........
2011.
Manual phenate, ...................... 4500-NH3 F-2011...... ..................... See footnote.\60\
salicylate, or other
substituted phenols
in Berthelot reaction
based methods.
[[Page 12]]
Automated phenate, 350.1,\30\ Rev. 2.0 4500-NH3 G-2011, 4500- ..................... I-4523-85.\2\
salicylate, or other (1993). NH3 H-2011.
substituted phenols
in Berthelot reaction
based methods.
Automated electrode... ...................... ..................... ..................... See footnote.\7\
Ion Chromatography.... ...................... ..................... D6919-09.............
Automated gas ...................... ..................... ..................... Timberline Ammonia-
diffusion, followed 001.\74\
by conductivity cell
analysis.
5. Antimony--Total,\4\ mg/L........ Digestion,\4\ followed
by any of the
following:
AA direct aspiration ...................... 3111 B-2011..........
\36\.
AA furnace............ ...................... 3113 B-2010..........
STGFAA................ 200.9, Rev. 2.2 (1994)
ICP/AES \36\.......... 200.5, Rev 4.2 (2003); 3120 B-2011.......... D1976-12............. I-4471-97.\50\
\68\ 200.7, Rev. 4.4
(1994).
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14,\3\ I-4471-
97.\50\
6. Arsenic-Total,\4\ mg/L.......... Digestion,\4\ followed 206.5 (Issued 1978)
by any of the \1\.
following:.
AA gaseous hydride.... ...................... 3114 B-2011 or 3114 C- D2972-08 (B)......... I-3062-85.\2\
2011.
AA furnace............ ...................... 3113 B-2010.......... D2972-08 (C)......... I-4063-98.\49\
STGFAA................ 200.9, Rev. 2.2 (1994)
ICP/AES \36\.......... 200.5, Rev 4.2 (2003); 3120 B-2011.......... D1976-12.............
\68\ 200.7, Rev. 4.4
(1994).
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14,\3\ I-4020-
05.\70\
Colorimetric (SDDC)... ...................... 3500-As B-2011....... D2972-08 (A)......... I-3060-85.\2\
7. Barium--Total,\4\ mg/L.......... Digestion,\4\ followed
by any of the
following:
AA direct aspiration ...................... 3111 D-2011.......... ..................... I-3084-85.\2\
\36\.
AA furnace............ ...................... 3113 B-2010.......... D4382-12.............
ICP/AES \36\.......... 200.5, Rev 4.2 (2003); 3120 B-2011.......... ..................... I-4471-97.\50\
\68\ 200.7, Rev. 4.4
(1994).
[[Page 13]]
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14,\3\ I-4471-
97.\50\
DCP \36\.............. ...................... ..................... ..................... See footnote.\34\
8. Beryllium--Total,\4\ mg/L....... Digestion,\4\ followed
by any of the
following:.
AA direct aspiration.. ...................... 3111 D-2011 or 3111 E- D3645-08 (A)......... I-3095-85.\2\
2011.
AA furnace............ ...................... 3113 B-2010.......... D3645-08 (B).........
STGFAA................ 200.9, Rev. 2.2 (1994)
ICP/AES............... 200.5, Rev 4.2 (2003); 3120 B-2011.......... D1976-12............. I-4471-97.\50\
\68\ 200.7, Rev. 4.4
(1994).
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14,\3\ I-4471-
97.\50\
DCP................... ...................... ..................... D4190-08............. See footnote.\34\
Colorimetric ...................... See footnote.\61\
(aluminon).
9. Biochemical oxygen demand Dissolved Oxygen ...................... 5210 B-2011.......... ..................... 973.44,\3\ p. 17,\9\
(BOD5), mg/L. Depletion. I-1578-78,\8\ See
footnote.10 63
10. Boron--Total,\37\ mg/L......... Colorimetric ...................... 4500-B B-2011........ ..................... I-3112-85.\2\
(curcumin).
ICP/AES............... 200.5, Rev 4.2 (2003); 3120 B-2011.......... D1976-12............. I-4471-97.\50\
\68\ 200.7, Rev. 4.4
(1994).
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14,\3\ I-4471-
97.\50\
DCP................... ...................... ..................... D4190-08............. See footnote.\34\
11. Bromide, mg/L.................. Electrode............. ...................... ..................... D1246-10............. I-1125-85.\2\
Ion Chromatography.... 300.0, Rev 2.1 (1993) 4110 B-2011, C-2011, D4327-03............. 993.30.\3\
and 300.1, Rev 1.0 D-2011.
(1997).
CIE/UV................ ...................... 4140 B-2011.......... D6508-10............. D6508, Rev. 2.\54\
12. Cadmium--Total,\4\ mg/L........ Digestion,\4\ followed
by any of the
following:
AA direct aspiration ...................... 3111 B-2011 or 3111 C- D3557-12 (A or B).... 974.27,\3\ p. 37,\9\
\36\. 2011. I-3135-85\2\ or I-
3136-85.\2\
AA furnace............ ...................... 3113 B-2010.......... D3557-12 (D)......... I-4138-89.\51\
STGFAA................ 200.9, Rev. 2.2 (1994)
ICP/AES \36\.......... 200.5, Rev 4.2 (2003); 3120 B-2011.......... D1976-12............. I-1472-85 \2\ or I-
\68\ 200.7, Rev. 4.4 4471-97.\50\
(1994).
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14,\3\ I-4471-
97.\50\
DCP \36\.............. ...................... ..................... D4190-08............. See footnote.\34\
Voltametry \11\....... ...................... ..................... D3557-12 (C).........
[[Page 14]]
Colorimetric ...................... 3500-Cd-D-1990.......
(Dithizone).
13. Calcium--Total,\4\ mg/L........ Digestion,\4\ followed
by any of the
following:
AA direct aspiration.. ...................... 3111 B-2011.......... D511-09(B)........... I-3152-85.\2\
ICP/AES............... 200.5, Rev 4.2 (2003); 3120 B-2011.......... ..................... I-4471-97.\50\
\68\ 200.7, Rev. 4.4
(1994).
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14.\3\
DCP................... ...................... ..................... ..................... See footnote.\34\
Titrimetric (EDTA).... ...................... 3500-Ca B-2011....... D511-09 (A)..........
Ion Chromatography.... ...................... ..................... D6919-09.............
14. Carbonaceous biochemical oxygen Dissolved Oxygen ...................... 5210 B-2011.......... ..................... See footnote.35 63
demand (CBOD5), mg/L \12\. Depletion with
nitrification
inhibitor.
15. Chemical oxygen demand (COD), Titrimetric........... 410.3 (Rev. 1978) \1\. 5220 B-2011 or C-2011 D1252-06 (A)......... 973.46,\3\ p. 17,\9\
mg/L. I-3560-85.\2\
Spectrophotometric, 410.4, Rev. 2.0 (1993) 5220 D-2011.......... D1252-06 (B)......... See footnotes.13 14,
manual or automatic. I-3561-85.\2\
16. Chloride, mg/L................. Titrimetric: (silver ...................... 4500-Cl- B-2011...... D512-04 (B).......... I-1183-85.\2\
nitrate).
(Mercuric nitrate).... ...................... 4500-Cl- C-2011...... D512-04 (A).......... 973.51,\3\ I-1184-
85.\2\
Colorimetric: Manual.. ...................... ..................... ..................... I-1187-85.\2\
Automated ...................... 4500-Cl- E-2011...... ..................... I-2187-85.\2\
(ferricyanide).
Potentiometric ...................... 4500-Cl- D-2011......
Titration.
Ion Selective ...................... ..................... D512-04 (C)..........
Electrode.
Ion Chromatography.... 300.0, Rev 2.1 (1993) 4110 B-2011 or 4110 C- D4327-03............. 993.30,\3\ I-2057-
and 300.1, Rev 1.0 2011. 90.\51\
(1997).
CIE/UV................ ...................... 4140 B-2011.......... D6508-10............. D6508, Rev. 2.\54\
17. Chlorine-Total residual, mg/L.. Amperometric direct... ...................... 4500-Cl D-2011....... D1253-08.............
Amperometric direct ...................... 4500-Cl E-2011.......
(low level).
Iodometric direct..... ...................... 4500-Cl B-2011.......
Back titration ether ...................... 4500-Cl C-2011.......
end-point \15\.
DPD-FAS............... ...................... 4500-Cl F-2011.......
[[Page 15]]
Spectrophotometric, ...................... 4500-Cl G-2011.......
DPD.
Electrode............. ...................... ..................... ..................... See footnote.\16\
17A. Chlorine-Free Available, mg/L. Amperometric direct... ...................... 4500-Cl D-2011....... D1253-08.............
Amperometric direct ...................... 4500-Cl E-2011.......
(low level).
DPD-FAS............... ...................... 4500-Cl F-2011.......
Spectrophotometric, ...................... 4500-Cl G-2011.......
DPD.
18. Chromium VI dissolved, mg/L.... 0.45-micron filtration
followed by any of
the following:
AA chelation- ...................... 3111 C-2011.......... ..................... I-1232-85.\2\
extraction.
Ion Chromatography.... 218.6, Rev. 3.3 (1994) 3500-Cr C-2011....... D5257-11............. 993.23.\3\
Colorimetric (diphenyl- ...................... 3500-Cr B-2011....... D1687-12 (A)......... I-1230-85.\2\
carbazide).
19. Chromium--Total,\4\ mg/L....... Digestion,\4\ followed
by any of the
following:
AA direct aspiration ...................... 3111 B-2011.......... D1687-12 (B)......... 974.27,\3\ I-3236-
\36\. 85.\2\
AA chelation- ...................... 3111 C-2011..........
extraction.
AA furnace............ ...................... 3113 B-2010.......... D1687-12 (C)......... I-3233-93.\46\
STGFAA................ 200.9, Rev. 2.2 (1994)
ICP/AES \36\.......... 200.5, Rev 4.2 3120 B-2011.......... D1976-12............. I-4471-97.\50\
(2003),\68\ 200.7,
Rev. 4.4 (1994).
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14,\3\ I-4020-
05.\70\
DCP \36\.............. ...................... ..................... D4190-08............. See footnote.\34\
Colorimetric (diphenyl- ...................... 3500-Cr B-2011.......
carbazide).
20. Cobalt--Total,\4\ mg/L......... Digestion,\4\ followed
by any of the
following:
AA direct aspiration.. ...................... 3111 B-2011 or 3111 C- D3558-08 (A or B).... p. 37,\9\ I-3239-
2011. 85.\2\
AA furnace............ ...................... 3113 B-2010.......... D3558-08 (C)......... I-4243-89.\51\
STGFAA................ 200.9, Rev. 2.2 (1994)
ICP/AES \36\.......... 200.7, Rev. 4.4 (1994) 3120 B-2011.......... D1976-12............. I-4471-97.\50\
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14,\3\ I-4020-
05.\70\
DCP................... ...................... ..................... D4190-08............. See footnote.\34\
[[Page 16]]
21. Color, platinum cobalt units or Colorimetric (ADMI)... ...................... 2120 F-2011 \78\.....
dominant wavelength, hue,
luminance purity.
Platinum cobalt visual ...................... 2120 B-2011.......... ..................... I-1250-85.\2\
comparison.
Spectrophotometric.... ...................... ..................... ..................... See footnote.\18\
22. Copper--Total,\4\ mg/L......... Digestion,\4\ followed
by any of the
following:
AA direct aspiration ...................... 3111 B-2011 or 3111 C- D1688-12 (A or B).... 974.27,\3\ p. 37,\9\
\36\. 2011. I-3270-85\2\ or I-
3271-85.\2\
AA furnace............ ...................... 3113 B-2010.......... D1688-12 (C)......... I-4274-89.\51\
STGFAA................ 200.9, Rev. 2.2 (1994)
ICP/AES \36\.......... 200.5, Rev 4.2 (2003); 3120 B-2011.......... D1976-12............. I-4471-97.\50\
\68\ 200.7, Rev. 4.4
(1994).
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14,\3\ I-4020-
05.\70\
DCP \36\.............. ...................... ..................... D4190-08............. See footnote.\34\
Colorimetric ...................... 3500-Cu B-2011.......
(Neocuproine).
Colorimetric ...................... 3500-Cu C-2011....... ..................... See footnote.\19\
(Bathocuproine).
23. Cyanide--Total, mg/L........... Automated UV digestion/ ...................... ..................... ..................... Kelada-01.\55\
distillation and
Colorimetry.
Segmented Flow ...................... ..................... D7511-12.............
Injection, In-Line
Ultraviolet
Digestion, followed
by gas diffusion
amperometry.
Manual distillation 335.4, Rev. 1.0 (1993) 4500-CN- B-2011 and C- D2036-09(A), D7284-13 10-204-00-1-X.\56\
with MgCl2, followed \57\. 2011.
by any of the
following:.
Flow Injection, gas ...................... ..................... D2036-09(A) D7284-13.
diffusion amperometry.
Titrimetric........... ...................... 4500-CN- D-2011...... D2036-09(A).......... p. 22.\9\
Spectrophotometric, ...................... 4500-CN- E-2011...... D2036-09(A).......... I-3300-85.\2\
manual.
[[Page 17]]
Semi-Automated \20\... 335.4, Rev. 1.0 (1993) ..................... ..................... 10-204-00-1-X,\56\ I-
\57\. 4302-85.\2\
Ion Chromatography.... ...................... ..................... D2036-09(A)..........
Ion Selective ...................... 4500-CN- F-2011...... D2036-09(A)..........
Electrode.
24. Cyanide--Available, mg/L....... Cyanide Amenable to ...................... 4500-CN- G-2011...... D2036-09(B)..........
Chlorination (CATC);
Manual distillation
with MgCl2, followed
by Titrimetric or
Spectrophotometric.
Flow injection and ...................... ..................... D6888-09............. OIA-1677-09.\44\
ligand exchange,
followed by gas
diffusion amperometry
\59\.
Automated Distillation ...................... ..................... ..................... Kelada-01.\55\
and Colorimetry (no
UV digestion).
24.A Cyanide--Free, mg/L........... Flow Injection, ...................... ..................... D7237-10............. OIA-1677-09.\44\
followed by gas
diffusion amperometry.
Manual micro-diffusion ...................... ..................... D4282-02.............
and colorimetry.
25. Fluoride--Total, mg/L.......... Manual ...................... 4500-F- B-2011.......
distillation,\6\
followed by any of
the following:
Electrode, manual..... ...................... 4500-F- C-2011....... D1179-10 (B).........
Electrode, automated.. ...................... ..................... ..................... I-4327-85.\2\
Colorimetric, (SPADNS) ...................... 4500-F- D-2011....... D1179-10 (A).........
Automated complexone.. ...................... 4500-F- E-2011.......
Ion Chromatography.... 300.0, Rev 2.1 (1993) 4110 B-2011 or C-2011 D4327-03............. 993.30.\3\
and 300.1, Rev 1.0
(1997).
CIE/UV................ ...................... 4140 B-2011.......... D6508-10............. D6508, Rev. 2.\54\
26. Gold--Total,\4\ mg/L........... Digestion,\4\ followed
by any of the
following:
AA direct aspiration.. ...................... 3111 B-2011..........
AA furnace............ 231.2 (Issued 1978) 3113 B-2010..........
\1\.
[[Page 18]]
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14.\3\
DCP................... ...................... ..................... ..................... See footnote.\34\
27. Hardness--Total, as CaCO3, mg/L Automated colorimetric 130.1 (Issued 1971)
\1\.
Titrimetric (EDTA).... ...................... 2340 C-2011.......... D1126-12............. 973.52B,\3\ I-1338-
85.\2\
Ca plus Mg as their ...................... 2340 B-2011..........
carbonates, by any
approved method for
Ca and Mg (See
Parameters 13 and
33), provided that
the sum of the lowest
point of quantitation
for Ca and Mg is
below the NPDES
permit requirement
for Hardness..
28. Hydrogen ion (pH), pH units.... Electrometric ...................... 4500-H+ B-2011....... D1293-99 (A or B).... 973.41,\3\ I-1586-
measurement. 85.\2\
Automated electrode... 150.2 (Dec. 1982) \1\. ..................... ..................... See footnote,\21\ I-
2587-85.\2\
29. Iridium--Total,\4\ mg/L........ Digestion,\4\ followed
by any of the
following:
AA direct aspiration.. ...................... 3111 B-2011..........
AA furnace............ 235.2 (Issued 1978)
\1\.
ICP/MS................ ...................... 3125 B-2011..........
30. Iron--Total,\4\ mg/L........... Digestion,\4\ followed
by any of the
following:
AA direct aspiration ...................... 3111 B-2011 or 3111 C- D1068-10 (A)......... 974.27,\3\ I-3381-
\36\. 2011. 85.\2\
AA furnace............ ...................... 3113 B-2010.......... D1068-10 (B).........
STGFAA................ 200.9, Rev. 2.2 (1994)
ICP/AES \36\.......... 200.5, Rev. 4.2 3120 B-2011.......... D1976-12............. I-4471-97.\50\
(2003); \68\ 200.7,
Rev. 4.4 (1994).
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14.\3\
DCP \36\.............. ...................... ..................... D4190-08............. See footnote.\34\
Colorimetric ...................... 3500-Fe B-2011....... D1068-10 (C)......... See footnote.\22\
(Phenanthroline).
[[Page 19]]
31. Kjeldahl Nitrogen \5\--Total, Manual digestion \20\ ...................... 4500-Norg B-2011 or C- D3590-11 (A)......... I-4515-91.\45\
(as N), mg/L. and distillation or 2011 and 4500-NH3 B-
gas diffusion, 2011.
followed by any of
the following:.
Titration............. ...................... 4500-NH3 C-2011...... ..................... 973.48.\3\
Nesslerization........ ...................... ..................... D1426-08 (A).........
Electrode............. ...................... 4500-NH3 D-2011 or E- D1426-08 (B).........
2011.
Semi-automated phenate 350.1, Rev. 2.0 (1993) 4500-NH3 G-2011 4500-
NH3 H-2011.
Manual phenate, ...................... 4500-NH3 F-2011...... ..................... See footnote.\60\
salicylate, or other
substituted phenols
in Berthelot reaction
based methods.
Automated gas ...................... ..................... ..................... Timberline Ammonia-
diffusion, followed 001.\74\
by conductivity cell
analysis.
--------------------------------------------------------------------------------------------------------------------
Automated Methods for TKN that do not require manual distillation.
--------------------------------------------------------------------------------------------------------------------
Automated phenate, 351.1 (Rev. 1978) \1\. ..................... ..................... I-4551-78.\8\
salicylate, or other
substituted phenols
in Berthelot reaction
based methods
colorimetric (auto
digestion and
distillation).
Semi-automated block 351.2, Rev. 2.0 (1993) 4500-Norg D-2011..... D3590-11 (B)......... I-4515-91.\45\
digestor colorimetric
(distillation not
required).
Block digester, ...................... ..................... ..................... See footnote.\39\
followed by Auto
distillation and
Titration.
Block digester, ...................... ..................... ..................... See footnote.\40\
followed by Auto
distillation and
Nesslerization.
[[Page 20]]
Block Digester, ...................... ..................... ..................... See footnote.\41\
followed by Flow
injection gas
diffusion
(distillation not
required).
Digestion with ...................... ..................... ..................... Hach 10242.\76\
peroxdisulfate,
followed by
Spectrophotometric
(2,6-dimethyl phenol).
Digestion with ...................... ..................... ..................... NCASI TNTP
persulfate, followed W10900.\77\
by Colorimetric.
32. Lead--Total,\4\ mg/L........... Digestion,\4\ followed
by any of the
following:
AA direct aspiration ...................... 3111 B-2011 or 3111 C- D3559-08 (A or B).... 974.27,\3\ I-3399-
\36\. 2011. 85.\2\
AA furnace............ ...................... 3113 B-2010.......... D3559-08 (D)......... I-4403-89.\51\
STGFAA................ 200.9, Rev. 2.2 (1994)
ICP/AES \36\.......... 200.5, Rev. 4.2 3120 B-2011.......... D1976-12............. I-4471-97.\50\
(2003); \68\ 200.7,
Rev. 4.4 (1994).
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14,\3\ I-4471-
97.\50\
DCP \36\.............. ...................... ..................... D4190-08............. See footnote.\34\
Voltametry \11\....... ...................... ..................... D3559-08 (C).........
Colorimetric ...................... 3500-Pb B-2011.......
(Dithizone).
33. Magnesium--Total,\4\ mg/L...... Digestion,\4\ followed
by any of the
following:
AA direct aspiration.. ...................... 3111 B-2011.......... D511-09 (B).......... 974.27,\3\ I-3447-
85.\2\
ICP/AES............... 200.5, Rev. 4.2 3120 B-2011.......... D1976-12............. I-4471-97.\50\
(2003); \68\ 200.7,
Rev. 4.4 (1994).
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14.\3\
DCP................... ...................... ..................... ..................... See footnote.\34\
Ion Chromatography.... ...................... ..................... D6919-09.............
34. Manganese--Total,\4\ mg/L...... Digestion,\4\ followed
by any of the
following:
AA direct aspiration ...................... 3111 B-2011.......... D858-12 (A or B)..... 974.27,\3\ I-3454-
\36\. 85.\2\
AA furnace............ ...................... 3113 B-2010.......... D858-12 (C)..........
STGFAA................ 200.9, Rev. 2.2 (1994)
[[Page 21]]
ICP/AES \36\.......... 200.5, Rev. 4.2 3120 B-2011.......... D1976-12............. I-4471-97.\50\
(2003); \68\ 200.7,
Rev. 4.4 (1994).
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14,\3\ I-4471-
97.\50\
DCP \36\.............. ...................... ..................... D4190-08............. See footnote.\34\
Colorimetric ...................... 3500-Mn B-2011....... ..................... 920.203.\3\
(Persulfate).
Colorimetric ...................... ..................... ..................... See footnote.\23\
(Periodate).
35. Mercury--Total,\4\ mg/L........ Cold vapor, Manual.... 245.1, Rev. 3.0 (1994) 3112 B-2011.......... D3223-12............. 977.22,\3\ I-3462-
85.\2\
Cold vapor, Automated. 245.2 (Issued 1974)
\1\.
Cold vapor atomic 245.7 Rev. 2.0 (2005) ..................... ..................... I-4464-01.\71\
fluorescence \17\.
spectrometry (CVAFS).
Purge and Trap CVAFS.. 1631E \43\............
36. Molybdenum--Total,\4\ mg/L..... Digestion,\4\ followed
by any of the
following:
AA direct aspiration.. ...................... 3111 D-2011.......... ..................... I-3490-85.\2\
AA furnace............ ...................... 3113 B-2010.......... ..................... I-3492-96.\47\
ICP/AES \36\.......... 200.7, Rev. 4.4 (1994) 3120 B-2011.......... D1976-12............. I-4471-97.\50\
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14,\3\ I-4471-
97.\50\
DCP................... ...................... ..................... ..................... See footnote.\34\
37. Nickel--Total,\4\ mg/L......... Digestion,\4\ followed
by any of the
following:
AA direct aspiration ...................... 3111 B-2011 or 3111 C- D1886-08 (A or B).... I-3499-85.\2\
\36\. 2011.
AA furnace............ ...................... 3113 B-2010.......... D1886-08 (C)......... I-4503-89.\51\
STGFAA................ 200.9, Rev. 2.2 (1994)
ICP/AES \36\.......... 200.5, Rev. 4.2 3120 B-2011.......... D1976-12............. I-4471-97.\50\
(2003); \68\ 200.7,
Rev. 4.4 (1994).
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14,\3\ I-4020-
05.\70\
DCP \36\.............. ...................... ..................... D4190-08............. See footnote.\34\
38. Nitrate (as N), mg/L........... Ion Chromatography.... 300.0, Rev. 2.1 (1993) 4110 B-2011 or C-2011 D4327-03............. 993.30.\3\
and 300.1, Rev. 1.0
(1997).
CIE/UV................ ...................... 4140 B-2011.......... D6508-10............. D6508, Rev. 2.\54\
Ion Selective ...................... 4500-NO3- D-2011.....
Electrode.
Colorimetric (Brucine 352.1 (Issued 1971) ..................... ..................... 973.50,\3\ 419D1 7 p.
sulfate). \1\. 28.\9\
[[Page 22]]
Spectrophotometric ...................... ..................... ..................... Hach 10206.\75\
(2,6-dimethylphenol).
Nitrate-nitrite N
minus Nitrite N (See
parameters 39 and 40).
39. Nitrate-nitrite (as N), mg/L... Cadmium reduction, ...................... 4500-NO3- E-2011..... D3867-04 (B).........
Manual.
Cadmium reduction, 353.2, Rev. 2.0 (1993) 4500-NO3- F-2011..... D3867-04 (A)......... I-2545-90.\51\
Automated.
Automated hydrazine... ...................... 4500-NO3- H-2011.....
Reduction/Colorimetric ...................... ..................... ..................... See footnote.\62\
Ion Chromatography.... 300.0, Rev. 2.1 (1993) 4110 B-2011 or C-2011 D4327-03............. 993.30.\3\
and 300.1, Rev. 1.0
(1997).
CIE/UV................ ...................... 4140 B-2011.......... D6508-10............. D6508, Rev. 2.\54\
Enzymatic reduction, ...................... ..................... ..................... I-2547-11,\72\ I-2548-
followed by automated 11,\72\ N07-
colorimetric 0003.\73\
determination.
Spectrophotometric ...................... ..................... ..................... Hach 10206.\75\
(2,6-dimethylphenol).
40. Nitrite (as N), mg/L........... Spectrophotometric: ...................... 4500-NO2- B-2011..... ..................... See footnote.\25\
Manual.
Automated ...................... ..................... ..................... I-4540-85,\2\ See
(Diazotization). footnote.\62\
Automated (*bypass 353.2, Rev. 2.0 (1993) 4500-NO3- F-2011..... D3867-04 (A)......... I-4545-85.\2\
cadmium reduction).
Manual (*bypass ...................... 4500-NO3- E-2011..... D3867-04 (B).........
cadmium reduction).
Ion Chromatography.... 300.0, Rev. 2.1 (1993) 4110 B-2011 or C-2011 D4327-03............. 993.30.\3\
and 300.1, Rev. 1.0
(1997).
CIE/UV................ ...................... 4140 B-2011.......... D6508-10............. D6508, Rev. 2.\54\
Automated (*bypass ...................... ..................... ..................... I-2547-11,\72\ I-2548-
Enzymatic reduction). 11,\72\ N07-
0003.\73\
[[Page 23]]
41. Oil and grease--Total Hexane extractable 1664 Rev. A; 1664 Rev. 5520 B-2011 \38\.....
recoverable, mg/L. material (HEM): n- B \42\.
Hexane extraction and
gravimetry.
Silica gel treated HEM 1664 Rev. A; 1664 Rev. 5520 B-2011 \38\ and
(SGT-HEM): Silica gel B \42\. 5520 F-2011\38\.
treatment and
gravimetry.
42. Organic carbon--Total (TOC), mg/ Combustion............ ...................... 5310 B-2011.......... D7573-09............. 973.47,\3\ p. 14.\24\
L.
Heated persulfate or ...................... 5310 C-2011, 5310 D- D4839-03............. 973.47,\3\ p. 14.\24\
UV persulfate 2011.
oxidation.
43. Organic nitrogen (as N), mg/L.. Total Kjeldahl N
(Parameter 31) minus
ammonia N (Parameter
4).
44. Ortho-phosphate (as P), mg/L... Ascorbic acid method:
Automated............. 365.1, Rev. 2.0 (1993) 4500-P F-2011 or G- ..................... 973.56,\3\ I-4601-
2011. 85.\2\
Manual single reagent. ...................... 4500-P E-2011........ D515-88 (A).......... 973.55.\3\
Manual two reagent.... 365.3 (Issued 1978)
\1\.
Ion Chromatography.... 300.0, Rev. 2.1 (1993) 4110 B-2011 or C-2011 D4327-03............. 993.30.\3\
and 300.1, Rev. 1.0
(1997).
CIE/UV................ ...................... 4140 B-2011.......... D6508-10............. D6508, Rev. 2.\54\
45. Osmium--Total,\4\ mg/L......... Digestion,\4\ followed
by any of the
following:
AA direct aspiration.. ...................... 3111 D-2011..........
AA furnace............ 252.2 (Issued 1978)
\1\.
46. Oxygen, dissolved, mg/L........ Winkler (Azide ...................... 4500-O (B-F)-2011.... D888-09 (A).......... 973.45B,\3\ I-1575-
modification). 78.\8\
Electrode............. ...................... 4500-O G-2011........ D888-09 (B).......... I-1576-78.\8\
Luminescence Based ...................... ..................... D888-09 (C).......... See footnote.\63\ See
Sensor. footnote.\64\
47. Palladium--Total,\4\ mg/L...... Digestion,\4\ followed
by any of the
following:
AA direct aspiration.. ...................... 3111 B-2011..........
[[Page 24]]
AA furnace............ 253.2 (Issued 1978)
\1\.
ICP/MS................ ...................... 3125 B-2011..........
DCP................... ...................... ..................... ..................... See footnote.\34\
48. Phenols, mg/L.................. Manual 420.1 (Rev. 1978) \1\. 5530 B-2010.......... D1783-01.............
distillation,\26\
followed by any of
the following:
Colorimetric (4AAP) 420.1 (Rev. 1978) \1\. 5530 D-2010 \27\..... D1783-01 (A or B)....
manual.
Automated colorimetric 420.4 Rev. 1.0 (1993).
(4AAP).
49. Phosphorus (elemental), mg/L... Gas-liquid ...................... ..................... ..................... See footnote.\28\
chromatography.
50. Phosphorus--Total, mg/L........ Digestion,\20\ ...................... 4500-P B(5)-2011..... ..................... 973.55.\3\
followed by any of
the following:
Manual................ 365.3 (Issued 1978) 4500-P E-2011........ D515-88 (A)..........
\1\.
Automated ascorbic 365.1 Rev. 2.0 (1993). 4500-P (F-H)-2011.... ..................... 973.56,\3\ I-4600-
acid reduction. 85.\2\
ICP/AES 4 36.......... 200.7, Rev. 4.4 (1994) 3120 B-2011.......... ..................... I-4471-97.\50\
Semi-automated block 365.4 (Issued 1974) ..................... D515-88 (B).......... I-4610-91.\48\
digestor (TKP \1\.
digestion).
Digestion with ...................... ..................... ..................... NCASI TNTP
persulfate, followed W10900.\77\
by Colorimetric.
51. Platinum--Total \4\, mg/L...... Digestion,\4\ followed
by any of the
following:
AA direct aspiration.. ...................... 3111 B-2011..........
AA furnace............ 255.2 (Issued 1978)
\1\.
ICP/MS................ ...................... 3125 B-2011..........
DCP................... ...................... ..................... ..................... See footnote.\34\
52. Potassium--Total \4\, mg/L..... Digestion,\4\ followed
by any of the
following:.
AA direct aspiration.. ...................... 3111 B-2011.......... ..................... 973.53,\3\ I-3630-
85.\2\
ICP/AES............... 200.7, Rev. 4.4 (1994) 3120 B-2011..........
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14.\3\
Flame photometric..... ...................... 3500-K B-2011........
Electrode............. ...................... 3500-K C-2011........
Ion Chromatography.... ...................... ..................... D6919-09.............
[[Page 25]]
53. Residue--Total, mg/L........... Gravimetric, 103- ...................... 2540 B-2011.......... ..................... I-3750-85.\2\
105[deg].
54. Residue--filterable, mg/L...... Gravimetric, 180[deg]. ...................... 2540 C-2011.......... D5907-13............. I-1750-85.\2\
55. Residue--non-filterable (TSS), Gravimetric, 103- ...................... 2540 D-2011.......... D5907-13............. I-3765-85.\2\
mg/L. 105[deg] post washing
of residue.
56. Residue--settleable, mg/L...... Volumetric, (Imhoff ...................... 2540 F-2011..........
cone), or gravimetric.
57. Residue--Volatile, mg/L........ Gravimetric, 550[deg]. 160.4 (Issued 1971) 2540-E-2011.......... ..................... I-3753-85.\2\
\1\.
58. Rhodium--Total \4\, mg/L....... Digestion,\4\ followed
by any of the
following:
AA direct aspiration, ...................... 3111 B-2011..........
or.
AA furnace............ 265.2 (Issued 1978)
\1\.
ICP/MS................ ...................... 3125 B-2011..........
59. Ruthenium--Total \4\, mg/L..... Digestion,\4\ followed
by any of the
following:
AA direct aspiration, ...................... 3111 B-2011..........
or.
AA furnace............ 267.2 \1\.............
ICP/MS................ ...................... 3125 B-2011..........
60. Selenium--Total \4\, mg/L...... Digestion,\4\ followed
by any of the
following:
AA furnace............ ...................... 3113 B-2010.......... D3859-08 (B)......... I-4668-98.\49\
STGFAA................ 200.9, Rev. 2.2 (1994)
ICP/AES \36\.......... 200.5, Rev 4.2 (2003) 3120 B-2011.......... D1976-12.............
\68\; 200.7, Rev. 4.4
(1994).
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14,\3\ I-4020-
05.\70\
AA gaseous hydride.... ...................... 3114 B-2011, or 3114 D3859-08 (A)......... I-3667-85.\2\
C-2011.
61. Silica--Dissolved,\37\ mg/L.... 0.45-micron filtration
followed by any of
the following:
Colorimetric, Manual.. ...................... 4500-SiO2 C-2011..... D859-10.............. I-1700-85.\2\
Automated ...................... 4500-SiO2 E-2011 or F- ..................... I-2700-85.\2\
(Molybdosilicate). 2011.
ICP/AES............... 200.5, Rev. 4.2 (2003) 3120 B-2011.......... ..................... I-4471-97.\50\
\68\; 200.7, Rev. 4.4
(1994).
[[Page 26]]
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14.\3\
62. Silver--Total,4 31 mg/L........ Digestion,4 29
followed by any of
the following:
AA direct aspiration.. ...................... 3111 B-2011 or 3111 C- ..................... 974.27,\3\ p. 37,\9\
2011. I-3720-85.\2\
AA furnace............ ...................... 3113 B-2010.......... ..................... I-4724-89.\51\
STGFAA................ 200.9, Rev. 2.2 (1994)
ICP/AES............... 200.5, Rev. 4.2 (2003) 3120 B-2011.......... D1976-12............. I-4471-97.\50\
\68\; 200.7, Rev. 4.4
(1994).
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14,\3\ I-4471-
97.\50\
DCP................... ...................... ..................... ..................... See footnote.\34\
63. Sodium--Total,\4\ mg/L......... Digestion,\4\ followed
by any of the
following:
AA direct aspiration.. ...................... 3111 B-2011.......... ..................... 973.54,\3\ I-3735-
85.\2\
ICP/AES............... 200.5, Rev. 4.2 (2003) 3120 B-2011.......... ..................... I-4471-97.\50\
\68\; 200.7, Rev. 4.4
(1994).
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14.\3\
DCP................... ...................... ..................... ..................... See footnote.\34\
Flame photometric..... ...................... 3500-Na B-2011.......
Ion Chromatography.... ...................... ..................... D6919-09.............
64. Specific conductance, micromhos/ Wheatstone bridge..... 120.1 (Rev. 1982) \1\. 2510 B-2011.......... D1125-95(99) (A)..... 973.40,\3\ I-2781-
cm at 25 [deg]C. 85.\2\
65. Sulfate (as SO4), mg/L......... Automated colorimetric 375.2, Rev. 2.0 (1993) 4500-SO42- F-2011 or
G-2011.
Gravimetric........... ...................... 4500-SO42- C-2011 or ..................... 925.54.\3\
D-2011.
Turbidimetric......... ...................... 4500-SO42- E-2011.... D516-11..............
Ion Chromatography.... 300.0, Rev. 2.1 (1993) 4110 B-2011 or C-2011 D4327-03............. 993.30,\3\ I-4020-
and 300.1, Rev. 1.0 05.\70\
(1997).
CIE/UV................ ...................... 4140 B-2011.......... D6508-1010........... D6508, Rev. 2.\54\
66. Sulfide (as S), mg/L........... Sample Pretreatment... ...................... 4500-S2- B, C-2011...
Titrimetric (iodine).. ...................... 4500-S2- F-2011...... ..................... I-3840-85.\2\
Colorimetric ...................... 4500-S2- D-2011......
(methylene blue).
Ion Selective ...................... 4500-S2- G-2011...... D4658-09.............
Electrode.
[[Page 27]]
67. Sulfite (as SO3), mg/L......... Titrimetric (iodine- ...................... 4500-SO32- B-2011....
iodate).
68. Surfactants, mg/L.............. Colorimetric ...................... 5540 C-2011.......... D2330-02.............
(methylene blue).
69. Temperature, [deg]C............ Thermometric.......... ...................... 2550 B-2010.......... ..................... See footnote.\32\
70. Thallium--Total,\4\ mg/L....... Digestion,\4\ followed
by any of the
following:
AA direct aspiration.. ...................... 3111 B-2011..........
AA furnace............ 279.2 (Issued 1978) 3113 B-2010..........
\1\.
STGFAA................ 200.9, Rev. 2.2 (1994)
ICP/AES............... 200.7, Rev. 4.4 (1994) 3120 B-2011.......... D1976-12.............
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14,\3\ I-4471-
97.\50\
71. Tin--Total,\4\ mg/L............ Digestion,\4\ followed
by any of the
following:
AA direct aspiration.. ...................... 3111 B-2011.......... ..................... I-3850-78.\8\
AA furnace............ ...................... 3113 B-2010..........
STGFAA................ 200.9, Rev. 2.2 (1994)
ICP/AES............... 200.5, Rev. 4.2 (2003)
\68\; 200.7, Rev. 4.4
(1994).
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14.\3\
72. Titanium--Total,\4\ mg/L....... Digestion,\4\ followed
by any of the
following:
AA direct aspiration.. ...................... 3111 D-2011..........
AA furnace............ 283.2 (Issued 1978)
\1\.
ICP/AES............... 200.7, Rev. 4.4 (1994)
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14.\3\
DCP................... ...................... ..................... ..................... See footnote.\34\
73. Turbidity, NTU \53\............ Nephelometric......... 180.1, Rev. 2.0 (1993) 2130 B-2011.......... D1889-00............. I-3860-85.\2\ See
footnote.\65\ See
footnote.\66\ See
footnote.\67\
74. Vanadium--Total,\4\ mg/L....... Digestion,\4\ followed
by any of the
following:
AA direct aspiration.. ...................... 3111 D-2011..........
AA furnace............ ...................... 3113 B-2010.......... D3373-12.............
[[Page 28]]
ICP/AES............... 200.5, Rev. 4.2 3120 B-2011.......... D1976-12............. I-4471-97.\50\
(2003); \68\ 200.7,
Rev. 4.4 (1994).
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14,\3\ I-4020-
05.\70\
DCP................... ...................... ..................... D4190-08............. See footnote.\34\
Colorimetric (Gallic ...................... 3500-V B-2011........
Acid).
75. Zinc--Total,\4\ mg/L........... Digestion,\4\ followed
by any of the
following:
AA direct aspiration ...................... 3111 B-2011 or 3111 C- D1691-12 (A or B).... 974.27,\3\ p. 37,\9\
\36\. 2011. I-3900-85.\2\
AA furnace............ 289.2 (Issued 1978)
\1\.
ICP/AES \36\.......... 200.5, Rev. 4.2 (2003) 3120 B-2011.......... D1976-12............. I-4471-97.\50\
\68\; 200.7, Rev. 4.4
(1994).
ICP/MS................ 200.8, Rev. 5.4 (1994) 3125 B-2011.......... D5673-10............. 993.14,\3\ I-4020-
05.\70\
DCP \36\.............. ...................... ..................... D4190-08............. See footnote.\34\
Colorimetric (Zincon). ...................... 3500 Zn B-2011....... ..................... See footnote.\33\
76. Acid Mine Drainage............. ...................... 1627 \69\.............
--------------------------------------------------------------------------------------------------------------------------------------------------------
Table IB Notes:
\1\ Methods for Chemical Analysis of Water and Wastes, EPA-600/4-79-020. Revised March 1983 and 1979, where applicable. U.S. EPA.
\2\ Methods for Analysis of Inorganic Substances in Water and Fluvial Sediments, Techniques of Water-Resource Investigations of the U.S. Geological
Survey, Book 5, Chapter A1., unless otherwise stated. 1989. USGS.
\3\ Official Methods of Analysis of the Association of Official Analytical Chemists, Methods Manual, Sixteenth Edition, 4th Revision, 1998. AOAC
International.
\4\ For the determination of total metals (which are equivalent to total recoverable metals) the sample is not filtered before processing. A digestion
procedure is required to solubilize analytes in suspended material and to break down organic-metal complexes (to convert the analyte to a detectable
form for colorimetric analysis). For non-platform graphite furnace atomic absorption determinations, a digestion using nitric acid (as specified in
Section 4.1.3 of Methods for the Chemical Analysis of Water and Wastes) is required prior to analysis. The procedure used should subject the sample to
gentle, acid refluxing and at no time should the sample be taken to dryness. For direct aspiration flame atomic absorption determinations (FLAA) a
combination acid (nitric and hydrochloric acids) digestion is preferred prior to analysis. The approved total recoverable digestion is described as
Method 200.2 in Supplement I of ``Methods for the Determination of Metals in Environmental Samples'' EPA/600R-94/111, May, 1994, and is reproduced in
EPA Methods 200.7, 200.8, and 200.9 from the same Supplement. However, when using the gaseous hydride technique or for the determination of certain
elements such as antimony, arsenic, selenium, silver, and tin by non-EPA graphite furnace atomic absorption methods, mercury by cold vapor atomic
absorption, the noble metals and titanium by FLAA, a specific or modified sample digestion procedure may be required and in all cases the referenced
method write-up should be consulted for specific instruction and/or cautions. For analyses using inductively coupled plasma-atomic emission
spectrometry (ICP-AES), the direct current plasma (DCP) technique or EPA spectrochemical techniques (platform furnace AA, ICP-AES, and ICP-MS) use EPA
Method 200.2 or an approved alternate procedure (e.g., CEM microwave digestion, which may be used with certain analytes as indicated in Table IB); the
total recoverable digestion procedures in EPA Methods 200.7, 200.8, and 200.9 may be used for those respective methods. Regardless of the digestion
procedure, the results of the analysis after digestion procedure are reported as ``total'' metals.
\5\ Copper sulfate or other catalysts that have been found suitable may be used in place of mercuric sulfate.
[[Page 29]]
\6\ Manual distillation is not required if comparability data on representative effluent samples are on file to show that this preliminary distillation
step is not necessary: However, manual distillation will be required to resolve any controversies. In general, the analytical method should be
consulted regarding the need for distillation. If the method is not clear, the laboratory may compare a minimum of 9 different sample matrices to
evaluate the need for distillation. For each matrix, a matrix spike and matrix spike duplicate are analyzed both with and without the distillation
step. (A total of 36 samples, assuming 9 matrices). If results are comparable, the laboratory may dispense with the distillation step for future
analysis. Comparable is defined as <20% RPD for all tested matrices). Alternatively the two populations of spike recovery percentages may be compared
using a recognized statistical test.
\7\ Industrial Method Number 379-75 WE Ammonia, Automated Electrode Method, Technicon Auto Analyzer II. February 19, 1976. Bran & Luebbe Analyzing
Technologies Inc.
\8\ The approved method is that cited in Methods for Determination of Inorganic Substances in Water and Fluvial Sediments, Techniques of Water-Resources
Investigations of the U.S. Geological Survey, Book 5, Chapter A1. 1979. USGS.
\9\ American National Standard on Photographic Processing Effluents. April 2, 1975. American National Standards Institute.
\10\ In-Situ Method 1003-8-2009, Biochemical Oxygen Demand (BOD) Measurement by Optical Probe. 2009. In-Situ Incorporated.
\11\ The use of normal and differential pulse voltage ramps to increase sensitivity and resolution is acceptable.
\12\ Carbonaceous biochemical oxygen demand (CBOD5) must not be confused with the traditional BOD5 test method which measures ``total 5-day BOD.'' The
addition of the nitrification inhibitor is not a procedural option, but must be included to report the CBOD5 parameter. A discharger whose permit
requires reporting the traditional BOD5 may not use a nitrification inhibitor in the procedure for reporting the results. Only when a discharger's
permit specifically states CBOD5 is required can the permittee report data using a nitrification inhibitor.
\13\ OIC Chemical Oxygen Demand Method. 1978. Oceanography International Corporation.
\14\ Method 8000, Chemical Oxygen Demand, Hach Handbook of Water Analysis, 1979. Hach Company.
\15\ The back titration method will be used to resolve controversy.
\16\ Orion Research Instruction Manual, Residual Chlorine Electrode Model 97-70. 1977. Orion Research Incorporated. The calibration graph for the Orion
residual chlorine method must be derived using a reagent blank and three standard solutions, containing 0.2, 1.0, and 5.0 mL 0.00281 N potassium
iodate/100 mL solution, respectively.
\17\ Method 245.7, Mercury in Water by Cold Vapor Atomic Fluorescence Spectrometry, EPA-821-R-05-001. Revision 2.0, February 2005. US EPA.
\18\ National Council of the Paper Industry for Air and Stream Improvement (NCASI) Technical Bulletin 253 (1971) and Technical Bulletin 803, May 2000.
\19\ Method 8506, Bicinchoninate Method for Copper, Hach Handbook of Water Analysis. 1979. Hach Company.
\20\ When using a method with block digestion, this treatment is not required.
\21\ Industrial Method Number 378-75WA, Hydrogen ion (pH) Automated Electrode Method, Bran & Luebbe (Technicon) Autoanalyzer II. October 1976. Bran &
Luebbe Analyzing Technologies.
\22\ Method 8008, 1,10-Phenanthroline Method using FerroVer Iron Reagent for Water. 1980. Hach Company.
\23\ Method 8034, Periodate Oxidation Method for Manganese, Hach Handbook of Wastewater Analysis. 1979. Hach Company.
\24\ Methods for Analysis of Organic Substances in Water and Fluvial Sediments, Techniques of Water-Resources Investigations of the U.S. Geological
Survey, Book 5, Chapter A3, (1972 Revised 1987). 1987. USGS.
\25\ Method 8507, Nitrogen, Nitrite-Low Range, Diazotization Method for Water and Wastewater. 1979. Hach Company.
\26\ Just prior to distillation, adjust the sulfuric-acid-preserved sample to pH 4 with 1 + 9 NaOH.
\27\ The colorimetric reaction must be conducted at a pH of 10.0 0.2.
\28\ Addison, R.F., and R.G. Ackman. 1970. Direct Determination of Elemental Phosphorus by Gas-Liquid Chromatography, Journal of Chromatography,
47(3):421-426.
\29\ Approved methods for the analysis of silver in industrial wastewaters at concentrations of 1 mg/L and above are inadequate where silver exists as
an inorganic halide. Silver halides such as the bromide and chloride are relatively insoluble in reagents such as nitric acid but are readily soluble
in an aqueous buffer of sodium thiosulfate and sodium hydroxide to pH of 12. Therefore, for levels of silver above 1 mg/L, 20 mL of sample should be
diluted to 100 mL by adding 40 mL each of 2 M Na2S2O3and NaOH. Standards should be prepared in the same manner. For levels of silver below 1 mg/L the
approved method is satisfactory.
\30\ The use of EDTA decreases method sensitivity. Analysts may omit EDTA or replace with another suitable complexing reagent provided that all method
specified quality control acceptance criteria are met.
\31\ For samples known or suspected to contain high levels of silver (e.g., in excess of 4 mg/L), cyanogen iodide should be used to keep the silver in
solution for analysis. Prepare a cyanogen iodide solution by adding 4.0 mL of concentrated NH4OH, 6.5 g of KCN, and 5.0 mL of a 1.0 N solution of I2
to 50 mL of reagent water in a volumetric flask and dilute to 100.0 mL. After digestion of the sample, adjust the pH of the digestate to >7 to prevent
the formation of HCN under acidic conditions. Add 1 mL of the cyanogen iodide solution to the sample digestate and adjust the volume to 100 mL with
reagent water (NOT acid). If cyanogen iodide is added to sample digestates, then silver standards must be prepared that contain cyanogen iodide as
well. Prepare working standards by diluting a small volume of a silver stock solution with water and adjusting the pH>7 with NH4OH. Add 1 mL of the
cyanogen iodide solution and let stand 1 hour. Transfer to a 100-mL volumetric flask and dilute to volume with water.
\32\ ``Water Temperature-Influential Factors, Field Measurement and Data Presentation,'' Techniques of Water-Resources Investigations of the U.S.
Geological Survey, Book 1, Chapter D1. 1975. USGS.
\33\ Method 8009, Zincon Method for Zinc, Hach Handbook of Water Analysis, 1979. Hach Company.
\34\ Method AES0029, Direct Current Plasma (DCP) Optical Emission Spectrometric Method for Trace Elemental Analysis of Water and Wastes. 1986-Revised
1991. Thermo Jarrell Ash Corporation.
[[Page 30]]
\35\ In-Situ Method 1004-8-2009, Carbonaceous Biochemical Oxygen Demand (CBOD) Measurement by Optical Probe. 2009. In-Situ Incorporated.
\36\ Microwave-assisted digestion may be employed for this metal, when analyzed by this methodology. Closed Vessel Microwave Digestion of Wastewater
Samples for Determination of Metals. April 16, 1992. CEM Corporation.
\37\ When determining boron and silica, only plastic, PTFE, or quartz laboratory ware may be used from start until completion of analysis.
\38\ Only use n-hexane (n-Hexane--85% minimum purity, 99.0% min. saturated C6 isomers, residue less than 1 mg/L) extraction solvent when determining Oil
and Grease parameters--Hexane Extractable Material (HEM), or Silica Gel Treated HEM (analogous to EPA Methods 1664 Rev. A and 1664 Rev. B). Use of
other extraction solvents is prohibited.
\39\ Method PAI-DK01, Nitrogen, Total Kjeldahl, Block Digestion, Steam Distillation, Titrimetric Detection. Revised December 22, 1994. OI Analytical.
\40\ Method PAI-DK02, Nitrogen, Total Kjeldahl, Block Digestion, Steam Distillation, Colorimetric Detection. Revised December 22, 1994. OI Analytical.
\41\ Method PAI-DK03, Nitrogen, Total Kjeldahl, Block Digestion, Automated FIA Gas Diffusion. Revised December 22, 1994. OI Analytical.
\42\ Method 1664 Rev. B is the revised version of EPA Method 1664 Rev. A. U.S. EPA. February 1999, Revision A. Method 1664, n-Hexane Extractable
Material (HEM; Oil and Grease) and Silica Gel Treated n-Hexane Extractable Material (SGT-HEM; Non-polar Material) by Extraction and Gravimetry. EPA-
821-R-98-002. U.S. EPA. February 2010, Revision B. Method 1664, n-Hexane Extractable Material (HEM; Oil and Grease) and Silica Gel Treated n-Hexane
Extractable Material (SGT-HEM; Non-polar Material) by Extraction and Gravimetry. EPA-821-R-10-001.
\43\ Method 1631, Revision E, Mercury in Water by Oxidation, Purge and Trap, and Cold Vapor Atomic Fluorescence Spectrometry, EPA-821-R-02-019. Revision
E. August 2002, U.S. EPA. The application of clean techniques described in EPA's Method 1669: Sampling Ambient Water for Trace Metals at EPA Water
Quality Criteria Levels, EPA-821-R-96-011, are recommended to preclude contamination at low-level, trace metal determinations.
\44\ Method OIA-1677-09, Available Cyanide by Ligand Exchange and Flow Injection Analysis (FIA). 2010. OI Analytical.
\45\ Open File Report 00-170, Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory--Determination of Ammonium Plus
Organic Nitrogen by a Kjeldahl Digestion Method and an Automated Photometric Finish that Includes Digest Cleanup by Gas Diffusion. 2000. USGS.
\46\ Open File Report 93-449, Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory--Determination of Chromium in Water by
Graphite Furnace Atomic Absorption Spectrophotometry. 1993. USGS.
\47\ Open File Report 97-198, Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory--Determination of Molybdenum by
Graphite Furnace Atomic Absorption Spectrophotometry. 1997. USGS.
\48\ Open File Report 92-146, Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory--Determination of Total Phosphorus by
Kjeldahl Digestion Method and an Automated Colorimetric Finish That Includes Dialysis. 1992. USGS.
\49\ Open File Report 98-639, Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory--Determination of Arsenic and Selenium
in Water and Sediment by Graphite Furnace-Atomic Absorption Spectrometry. 1999. USGS.
\50\ Open File Report 98-165, Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory--Determination of Elements in Whole-
water Digests Using Inductively Coupled Plasma-Optical Emission Spectrometry and Inductively Coupled Plasma-Mass Spectrometry. 1998. USGS.
\51\ Open File Report 93-125, Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory--Determination of Inorganic and
Organic Constituents in Water and Fluvial Sediments. 1993. USGS.
\52\ Unless otherwise indicated, all EPA methods, excluding EPA Method 300.1, are published in U.S. EPA. May 1994. Methods for the Determination of
Metals in Environmental Samples, Supplement I, EPA/600/R-94/111; or U.S. EPA. August 1993. Methods for the Determination of Inorganic Substances in
Environmental Samples, EPA/600/R-93/100. EPA Method 300.1 is US EPA. Revision 1.0, 1997, including errata cover sheet April 27, 1999. Determination of
Inorganic Ions in Drinking Water by Ion Chromatography.
\53\ Styrene divinyl benzene beads (e.g., AMCO-AEPA-1 or equivalent) and stabilized formazin (e.g., Hach StablCal\TM\ or equivalent) are acceptable
substitutes for formazin.
\54\ Method D6508-10, Test Method for Determination of Dissolved Inorganic Anions in Aqueous Matrices Using Capillary Ion Electrophoresis and Chromate
Electrolyte. 2010. ASTM.
\55\ Kelada-01, Kelada Automated Test Methods for Total Cyanide, Acid Dissociable Cyanide, and Thiocyanate, EPA 821-B-01-009, Revision 1.2, August 2001.
US EPA. Note: A 450-W UV lamp may be used in this method instead of the 550-W lamp specified if it provides performance within the quality control
(QC) acceptance criteria of the method in a given instrument. Similarly, modified flow cell configurations and flow conditions may be used in the
method, provided that the QC acceptance criteria are met.
\56\ QuikChem Method 10-204-00-1-X, Digestion and Distillation of Total Cyanide in Drinking and Wastewaters using MICRO DIST and Determination of
Cyanide by Flow Injection Analysis. Revision 2.2, March 2005. Lachat Instruments.
\57\ When using sulfide removal test procedures described in EPA Method 335.4-1, reconstitute particulate that is filtered with the sample prior to
distillation.
\58\ Unless otherwise stated, if the language of this table specifies a sample digestion and/or distillation ``followed by'' analysis with a method,
approved digestion and/or distillation are required prior to analysis.
[[Page 31]]
\59\ Samples analyzed for available cyanide using OI Analytical method OIA-1677-09 or ASTM method D6888-09 that contain particulate matter may be
filtered only after the ligand exchange reagents have been added to the samples, because the ligand exchange process converts complexes containing
available cyanide to free cyanide, which is not removed by filtration. Analysts are further cautioned to limit the time between the addition of the
ligand exchange reagents and sample filtration to no more than 30 minutes to preclude settling of materials in samples.
\60\ Analysts should be aware that pH optima and chromophore absorption maxima might differ when phenol is replaced by a substituted phenol as the color
reagent in Berthelot Reaction (``phenol-hypochlorite reaction'') colorimetric ammonium determination methods. For example when phenol is used as the
color reagent, pH optimum and wavelength of maximum absorbance are about 11.5 and 635 nm, respectively--see, Patton, C.J. and S.R. Crouch. March 1977.
Anal. Chem. 49:464-469. These reaction parameters increase to pH 12.6 and 665 nm when salicylate is used as the color reagent--see, Krom,
M.D. April 1980. The Analyst 105:305-316.
\61\ If atomic absorption or ICP instrumentation is not available, the aluminon colorimetric method detailed in the 19th Edition of Standard Methods may
be used. This method has poorer precision and bias than the methods of choice.
\62\ Easy (1-Reagent) Nitrate Method, Revision November 12, 2011. Craig Chinchilla.
\63\ Hach Method 10360, Luminescence Measurement of Dissolved Oxygen in Water and Wastewater and for Use in the Determination of BOD5 and cBOD5.
Revision 1.2, October 2011. Hach Company. This method may be used to measure dissolved oxygen when performing the methods approved in Table IB for
measurement of biochemical oxygen demand (BOD) and carbonaceous biochemical oxygen demand (CBOD).
\64\ In-Situ Method 1002-8-2009, Dissolved Oxygen (DO) Measurement by Optical Probe. 2009. In-Situ Incorporated.
\65\ Mitchell Method M5331, Determination of Turbidity by Nephelometry. Revision 1.0, July 31, 2008. Leck Mitchell.
\66\ Mitchell Method M5271, Determination of Turbidity by Nephelometry. Revision 1.0, July 31, 2008. Leck Mitchell.
\67\ Orion Method AQ4500, Determination of Turbidity by Nephelometry. Revision 5, March 12, 2009. Thermo Scientific.
\68\ EPA Method 200.5, Determination of Trace Elements in Drinking Water by Axially Viewed Inductively Coupled Plasma-Atomic Emission Spectrometry, EPA/
600/R-06/115. Revision 4.2, October 2003. US EPA.
\69\ Method 1627, Kinetic Test Method for the Prediction of Mine Drainage Quality, EPA-821-R-09-002. December 2011. US EPA.
\70\ Techniques and Methods Book 5-B1, Determination of Elements in Natural-Water, Biota, Sediment and Soil Samples Using Collision/Reaction Cell
Inductively Coupled Plasma-Mass Spectrometry, Chapter 1, Section B, Methods of the National Water Quality Laboratory, Book 5, Laboratory Analysis,
2006. USGS.
\71\ Water-Resources Investigations Report 01-4132, Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory--Determination
of Organic Plus Inorganic Mercury in Filtered and Unfiltered Natural Water with Cold Vapor-Atomic Fluorescence Spectrometry, 2001. USGS.
\72\ USGS Techniques and Methods 5-B8, Chapter 8, Section B, Methods of the National Water Quality Laboratory Book 5, Laboratory Analysis, 2011 USGS.
\73\ NECi Method N07-0003, ''Nitrate Reductase Nitrate-Nitrogen Analysis,'' Revision 9.0, March 2014, The Nitrate Elimination Co., Inc.
\74\ Timberline Instruments, LLC Method Ammonia-001, ``Determination of Inorganic Ammonia by Continuous Flow Gas Diffusion and Conductivity Cell
Analysis,'' June 2011, Timberline Instruments, LLC.
\75\ Hach Company Method 10206, ``Spectrophotometric Measurement of Nitrate in Water and Wastewater,'' Revision 2.1, January 2013, Hach Company.
\76\ Hach Company Method 10242, ``Simplified Spectrophotometric Measurement of Total Kjeldahl Nitrogen in Water and Wastewater,'' Revision 1.1, January
2013, Hach Company.
\77\ National Council for Air and Stream Improvement (NCASI) Method TNTP-W10900, ``Total (Kjeldahl) Nitrogen and Total Phosphorus in Pulp and Paper
Biologically Treated Effluent by Alkaline Persulfate Digestion,'' June 2011, National Council for Air and Stream Improvement, Inc.
\78\ The pH adjusted sample is to be adjusted to 7.6 for NPDES reporting purposes.
[[Page 32]]
Table IC--List of Approved Test Procedures for Non-Pesticide Organic Compounds
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Parameter \1\ Method EPA 2 7 Standard methods ASTM Other
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1. Acenaphthene.................... GC.................... 610........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
HPLC.................. 610........................ 6440 B-2005............... D4657-92 (98).......................
2. Acenaphthylene.................. GC.................... 610........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
HPLC.................. 610........................ 6440 B-2005............... D4657-92 (98).......................
3. Acrolein........................ GC.................... 603........................ ..........................
GC/MS................. 624.1,\4\ 1624B............ ..........................
4. Acrylonitrile................... GC.................... 603........................ ..........................
GC/MS................. 624.1,\4\ 1624B............ ..........................
5. Anthracene...................... GC.................... 610........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
HPLC.................. 610........................ 6440 B-2005............... D4657-92 (98).......................
6. Benzene......................... GC.................... 602........................ 6200 C-2011...............
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
7. Benzidine....................... Spectro-photometric... ........................... .......................... .................................... See footnote,\3\ p.1.
GC/MS................. 625.1\5\, 1625B............ 6410 B-2000...............
HPLC.................. 605........................ ..........................
8. Benzo(a)anthracene.............. GC.................... 610........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
HPLC.................. 610........................ 6440 B-2005............... D4657-92 (98).......................
9. Benzo(a)pyrene.................. GC.................... 610........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
HPLC.................. 610........................ 6440 B-2005............... D4657-92 (98).......................
10. Benzo(b)fluoranthene........... GC.................... 610........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
HPLC.................. 610........................ 6440 B-2005............... D4657-92 (98).......................
11. Benzo(g,h,i)perylene........... GC.................... 610........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
HPLC.................. 610........................ 6440 B-2005............... D4657-92 (98).......................
12. Benzo(k)fluoranthene........... GC.................... 610........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
HPLC.................. 610........................ 6440 B-2005............... D4657-92 (98).......................
13. Benzyl chloride................ GC.................... ........................... .......................... .................................... See footnote,\3\ p. 130.
GC/MS................. ........................... .......................... .................................... See footnote,\6\ p. S102.
14. Butyl benzyl phthalate......... GC.................... 606........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
15. bis(2-Chloroethoxy) methane.... GC.................... 611........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
16. bis(2-Chloroethyl) ether....... GC.................... 611........................ ..........................
[[Page 33]]
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
17. bis(2-Ethylhexyl) phthalate.... GC.................... 606........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
18. Bromodichloromethane........... GC.................... 601........................ 6200 C-2011...............
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
19. Bromoform...................... GC.................... 601........................ 6200 C-2011...............
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
20. Bromomethane................... GC.................... 601........................ 6200 C-2011...............
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
21. 4-Bromophenyl phenyl ether..... GC.................... 611........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
22. Carbon tetrachloride........... GC.................... 601........................ 6200 C-2011............... .................................... See footnote,\3\ p. 130.
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
23. 4-Chloro-3-methyl phenol....... GC.................... 604........................ 6420 B-2000...............
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
24. Chlorobenzene.................. GC.................... 601, 602................... 6200 C-2011............... .................................... See footnote,\3\ p. 130.
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
25. Chloroethane................... GC.................... 601........................ 6200 C-2011...............
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
26. 2-Chloroethylvinyl ether....... GC.................... 601........................ ..........................
GC/MS................. 624.1, 1624B............... ..........................
27. Chloroform..................... GC.................... 601........................ 6200 C-2011............... .................................... See footnote,\3\ p. 130.
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
28. Chloromethane.................. GC.................... 601........................ 6200 C-2011...............
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
29. 2-Chloronaphthalene............ GC.................... 612........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
30. 2-Chlorophenol................. GC.................... 604........................ 6420 B-2000...............
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
31. 4-Chlorophenyl phenyl ether.... GC.................... 611........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
32. Chrysene....................... GC.................... 610........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
HPLC.................. 610........................ 6440 B-2005............... D4657-92 (98).......................
33. Dibenzo(a,h)anthracene......... GC.................... 610........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
HPLC.................. 610........................ 6440 B-2005............... D4657-92 (98).......................
34. Dibromochloromethane........... GC.................... 601........................ 6200 C-2011...............
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
35. 1,2-Dichlorobenzene............ GC.................... 601, 602................... 6200 C-2011...............
GC/MS................. 624.1, 1625B............... 6200 B-2011............... .................................... See footnote,\9\ p. 27.
36. 1,3-Dichlorobenzene............ GC.................... 601, 602................... 6200 C-2011...............
GC/MS................. 624.1, 1625B............... 6200 B-2011............... .................................... See footnote,\9\ p. 27.
37. 1,4-Dichlorobenzene............ GC.................... 601, 602................... 6200 C-2011...............
[[Page 34]]
GC/MS................. 624.1, 1625B............... 6200 B-2011............... .................................... See footnote,\9\ p. 27.
38. 3,3'-Dichlorobenzidine......... GC/MS................. 625.1, 1625B............... 6410 B-2000...............
HPLC.................. 605........................ ..........................
39. Dichlorodifluoromethane........ GC.................... 601........................ ..........................
GC/MS................. ........................... 6200 C-2011...............
40. 1,1-Dichloroethane............. GC.................... 601........................ 6200 C-2011...............
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
41. 1,2-Dichloroethane............. GC.................... 601........................ 6200 C-2011...............
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
42. 1,1-Dichloroethene............. GC.................... 601........................ 6200 C-2011...............
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
43. trans-1,2-Dichloroethene....... GC.................... 601........................ 6200 C-2011...............
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
44. 2,4-Dichlorophenol............. GC.................... 604........................ 6420 B-2000...............
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
45. 1,2-Dichloropropane............ GC.................... 601........................ 6200 C-2011...............
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
46. cis-1,3-Dichloropropene........ GC.................... 601........................ 6200 C-2011...............
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
47. trans-1,3-Dichloropropene...... GC.................... 601........................ 6200 C-2011...............
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
48. Diethyl phthalate.............. GC.................... 606........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
49. 2,4-Dimethylphenol............. GC.................... 604........................ 6420 B-2000...............
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
50. Dimethyl phthalate............. GC.................... 606........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
51. Di-n-butyl phthalate........... GC.................... 606........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
52. Di-n-octyl phthalate........... GC.................... 606........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
53. 2, 4-Dinitrophenol............. GC.................... 604........................ 6420 B-2000............... .................................... See footnote,\9\ p. 27.
GC/MS................. 625.1, 1625B............... 6410 B-2000...............
54. 2,4-Dinitrotoluene............. GC.................... 609........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
55. 2,6-Dinitrotoluene............. GC.................... 609........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
56. Epichlorohydrin................ GC.................... ........................... .......................... .................................... See footnote,\3\ p. 130.
GC/MS................. ........................... .......................... .................................... See footnote,\6\ p. S102.
57. Ethylbenzene................... GC.................... 602........................ 6200 C-2011...............
[[Page 35]]
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
58. Fluoranthene................... GC.................... 610........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
HPLC.................. 610........................ 6440 B-2005............... D4657-92 (98).......................
59. Fluorene....................... GC.................... 610........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
HPLC.................. 610........................ 6440 B-2005............... D4657-92 (98).......................
60. 1,2,3,4,6,7,8-Heptachloro- GC/MS................. 1613B...................... ..........................
dibenzofuran.
61. 1,2,3,4,7,8,9-Heptachloro- GC/MS................. 1613B...................... ..........................
dibenzofuran.
62. 1,2,3,4,6,7,8- Heptachloro- GC/MS................. 1613B...................... ..........................
dibenzo-p-dioxin.
63. Hexachlorobenzene.............. GC.................... 612........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
64. Hexachlorobutadiene............ GC.................... 612........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
65. Hexachlorocyclopentadiene...... GC.................... 612........................ ..........................
GC/MS................. 625.1,\5\ 1625B............ 6410 B-2000............... .................................... See footnote,\9\ p. 27.
66. 1,2,3,4,7,8-Hexachloro- GC/MS................. 1613B...................... ..........................
dibenzofuran.
67. 1,2,3,6,7,8-Hexachloro- GC/MS................. 1613B...................... ..........................
dibenzofuran.
68. 1,2,3,7,8,9-Hexachloro- GC/MS................. 1613B...................... ..........................
dibenzofuran.
69. 2,3,4,6,7,8-Hexachloro- GC/MS................. 1613B...................... ..........................
dibenzofuran.
70. 1,2,3,4,7,8-Hexachloro-dibenzo- GC/MS................. 1613B...................... ..........................
p-dioxin.
71. 1,2,3,6,7,8-Hexachloro-dibenzo- GC/MS................. 1613B...................... ..........................
p-dioxin.
72. 1,2,3,7,8,9-Hexachloro-dibenzo- GC/MS................. 1613B...................... ..........................
p-dioxin.
73. Hexachloroethane............... GC.................... 612........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
74. Indeno(1,2,3-c,d) pyrene....... GC.................... 610........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
HPLC.................. 610........................ 6440 B-2005............... D4657-92 (98).......................
75. Isophorone..................... GC.................... 609........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
76. Methylene chloride............. GC.................... 601........................ 6200 C-2011............... .................................... See footnote,\3\ p. 130.
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
77. 2-Methyl-4,6-dinitrophenol..... GC.................... 604........................ 6420 B-2000...............
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
[[Page 36]]
78. Naphthalene.................... GC.................... 610........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
HPLC.................. 610........................ 6440 B-2005...............
79. Nitrobenzene................... GC.................... 609........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
HPLC.................. ........................... .......................... D4657-92 (98).......................
80. 2-Nitrophenol.................. GC.................... 604........................ 6420 B-2000...............
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
81. 4-Nitrophenol.................. GC.................... 604........................ 6420 B-2000...............
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
82. N-Nitrosodimethylamine......... GC.................... 607........................ ..........................
GC/MS................. 625.1,\5\ 1625B............ 6410 B-2000............... .................................... See footnote,\9\ p. 27.
83. N-Nitrosodi-n-propylamine...... GC.................... 607........................ ..........................
GC/MS................. 625.1,\5\ 1625B............ 6410 B-2000............... .................................... See footnote,\9\ p. 27.
84. N-Nitrosodiphenylamine......... GC.................... 607........................ ..........................
GC/MS................. 625.1,\5\ 1625B............ 6410 B-2000............... .................................... See footnote,\9\ p. 27.
85. Octachlorodibenzofuran......... GC/MS................. 1613B \10\................. ..........................
86. Octachlorodibenzo-p-dioxin..... GC/MS................. 1613B \10\................. ..........................
87. 2,2'-oxybis(1-chloropropane) GC.................... 611........................ ..........................
\12\ [also known as bis(2-Chloro-1-
methylethyl) ether].
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
88. PCB-1016....................... GC.................... 608.3...................... .......................... .................................... See footnote,\3\ p. 43; See
footnote.\8\
GC/MS................. 625.1...................... 6410 B-2000...............
89. PCB-1221....................... GC.................... 608.3...................... .......................... .................................... See footnote,\3\ p. 43; See
footnote.\8\
GC/MS................. 625.1...................... 6410 B-2000...............
90. PCB-1232....................... GC.................... 608.3...................... .......................... .................................... See footnote,\3\ p. 43; See
footnote.\8\
GC/MS................. 625.1...................... 6410 B-2000...............
91. PCB-1242....................... GC.................... 608.3...................... .......................... .................................... See footnote,\3\ p. 43; See
footnote.\8\
GC/MS................. 625.1...................... 6410 B-2000...............
92. PCB-1248....................... GC.................... 608.3...................... .......................... .................................... See footnote,\3\ p. 43; See
footnote.\8\
GC/MS................. 625.1...................... 6410 B-2000...............
93. PCB-1254....................... GC.................... 608.3...................... .......................... .................................... See footnote,\3\ p. 43; See
footnote.\8\
[[Page 37]]
GC/MS................. 625.1...................... 6410 B-2000...............
94. PCB-1260....................... GC.................... 608.3...................... .......................... .................................... See footnote,\3\ p. 43; See
footnote.\8\
GC/MS................. 625.1...................... 6410 B-2000...............
95. 1,2,3,7,8-Pentachloro- GC/MS................. 1613B...................... ..........................
dibenzofuran.
96. 2,3,4,7,8-Pentachloro- GC/MS................. 1613B...................... ..........................
dibenzofuran.
97. 1,2,3,7,8,-Pentachloro-dibenzo- GC/MS................. 1613B...................... ..........................
p-dioxin.
98. Pentachlorophenol.............. GC.................... 604........................ 6420 B-2000............... .................................... See footnote,\3\ p. 140.
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
99. Phenanthrene................... GC.................... 610........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
HPLC.................. 610........................ 6440 B-2005............... D4657-92 (98).......................
100. Phenol........................ GC.................... 604........................ 6420 B-2000...............
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
101. Pyrene........................ GC.................... 610........................ ..........................
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
HPLC.................. 610........................ 6440 B-2005............... D4657-92 (98).......................
102. 2,3,7,8-Tetrachloro- GC/MS................. 1613B \10\................. ..........................
dibenzofuran.
103. 2,3,7,8-Tetrachloro-dibenzo-p- GC/MS................. 613, 625.1,\5a\ 1613B...... ..........................
dioxin.
104. 1,1,2,2-Tetrachloroethane..... GC.................... 601........................ 6200 C-2011............... .................................... See footnote,\3\ p. 130.
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
105. Tetrachloroethene............. GC.................... 601........................ 6200 C-2011............... .................................... See footnote,\3\ p. 130.
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
106. Toluene....................... GC.................... 602........................ 6200 C-2011...............
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
107. 1,2,4-Trichlorobenzene........ GC.................... 612........................ .......................... .................................... See footnote,\3\ p. 130.
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
108. 1,1,1-Trichloroethane......... GC.................... 601........................ 6200 C-2011...............
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
109. 1,1,2-Trichloroethane......... GC.................... 601........................ 6200 C-2011............... .................................... See footnote,\3\ p. 130.
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
110. Trichloroethene............... GC.................... 601........................ 6200 C-2011...............
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
111. Trichlorofluoromethane........ GC.................... 601........................ 6200 C-2011...............
GC/MS................. 624.1...................... 6200 B-2011...............
112. 2,4,6-Trichlorophenol......... GC.................... 604........................ 6420 B-2000...............
GC/MS................. 625.1, 1625B............... 6410 B-2000............... .................................... See footnote,\9\ p. 27.
113. Vinyl chloride................ GC.................... 601........................ 6200 C-2011...............
GC/MS................. 624.1, 1624B............... 6200 B-2011...............
[[Page 38]]
114. Nonylphenol................... GC/MS................. ........................... .......................... D7065-11............................
115. Bisphenol A (BPA)............. GC/MS................. ........................... .......................... D7065-11............................
116. p-tert-Octylphenol (OP)....... GC/MS................. ........................... .......................... D7065-11............................
117. Nonylphenol Monoethoxylate GC/MS................. ........................... .......................... D7065-11............................
(NP1EO).
118. Nonylphenol Diethoxylate GC/MS................. ........................... .......................... D7065-11............................
(NP2EO).
119. Adsorbable Organic Halides Adsorption and 1650 \11\.................. ..........................
(AOX). Coulometric Titration.
120. Chlorinated Phenolics......... In Situ Acetylation 1653 \11\.................. .......................... ....................................
and GC/MS.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Table IC notes:
\1\ All parameters are expressed in micrograms per liter ([micro]g/L) except for Method 1613B, in which the parameters are expressed in picograms per liter (pg/L).
\2\ The full text of Methods 601-613, 1613B, 1624B, and 1625B are provided at appendix A, Test Procedures for Analysis of Organic Pollutants. The standardized test procedure to be used to
determine the method detection limit (MDL) for these test procedures is given at appendix B of this part, Definition and Procedure for the Determination of the Method Detection Limit. These
methods are available at: https://www.epa.gov/cwa-methods as individual PDF files.
\3\ Methods for Benzidine: Chlorinated Organic Compounds, Pentachlorophenol and Pesticides in Water and Wastewater. September 1978. U.S. EPA.
\4\ Method 624.1 may be used for quantitative determination of acrolein and acrylonitrile, provided that the laboratory has documentation to substantiate the ability to detect and quantify
these analytes at levels necessary to comply with any associated regulations. In addition, the use of sample introduction techniques other than simple purge-and-trap may be required. QC
acceptance criteria from Method 603 should be used when analyzing samples for acrolein and acrylonitrile in the absence of such criteria in Method 624.1.
\5\ Method 625.1 may be extended to include benzidine, hexachlorocyclopentadiene, N-nitrosodimethylamine, N-nitrosodi-n-propylamine, and N-nitrosodiphenylamine. However, when they are known to
be present, Methods 605, 607, and 612, or Method 1625B, are preferred methods for these compounds.
\5a\ Method 625.1 screening only.
\6\ Selected Analytical Methods Approved and Cited by the United States Environmental Protection Agency, Supplement to the 15th Edition of Standard Methods for the Examination of Water and
Wastewater. 1981. American Public Health Association (APHA).
\7\ Each analyst must make an initial, one-time demonstration of their ability to generate acceptable precision and accuracy with Methods 601-603, 1624B, and 1625B in accordance with
procedures each in Section 8.2 of each of these Methods. Additionally, each laboratory, on an on-going basis must spike and analyze 10% (5% for Methods 624.1 and 625.1 and 100% for methods
1624B and 1625B) of all samples to monitor and evaluate laboratory data quality in accordance with Sections 8.3 and 8.4 of these methods. When the recovery of any parameter falls outside the
quality control (QC) acceptance criteria in the pertinent method, analytical results for that parameter in the unspiked sample are suspect. The results should be reported but cannot be used
to demonstrate regulatory compliance. If the method does not contain QC acceptance criteria, control limits of three standard deviations around the mean of a minimum
of five replicate measurements must be used. These quality control requirements also apply to the Standard Methods, ASTM Methods, and other methods cited.
\8\ Organochlorine Pesticides and PCBs in Wastewater Using Empore\TM\ Disk. Revised October 28, 1994. 3M Corporation.
\9\ Method O-3116-87 is in Open File Report 93-125, Methods of Analysis by U.S. Geological Survey National Water Quality Laboratory--Determination of Inorganic and Organic Constituents in
Water and Fluvial Sediments. 1993. USGS.
\10\ Analysts may use Fluid Management Systems, Inc. Power-Prep system in place of manual cleanup provided the analyst meets the requirements of Method 1613B (as specified in Section 9 of the
method) and permitting authorities. Method 1613, Revision B, Tetra- through Octa-Chlorinated Dioxins and Furans by Isotope Dilution HRGC/HRMS. Revision B, 1994. U.S. EPA. The full text of
this method is provided in appendix A to this part and at https://www.epa.gov/cwa-methods/approved-cwa-methods-organic-compounds.
[[Page 39]]
\11\ Method 1650, Adsorbable Organic Halides by Adsorption and Coulometric Titration. Revision C, 1997 U.S. EPA. Method 1653, Chlorinated Phenolics in Wastewater by In Situ Acetylation and
GCMS. Revision A, 1997 U.S. EPA. The full text for both of these methods is provided at appendix A in part 430 of this chapter, The Pulp, Paper, and Paperboard Point Source Category.
\12\ The compound was formerly inaccurately labeled as 2,2'-oxybis(2-chloropropane) and bis(2-chloroisopropyl) ether. Some versions of Methods 611, and 1625 inaccurately list the analyte as
``bis(2-chloroisopropyl)ether,'' but use the correct CAS number of 108-60-1.
Table ID--List of Approved Test Procedures for Pesticides \1\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Parameter Method EPA 2 7 10 Standard methods ASTM Other
--------------------------------------------------------------------------------------------------------------------------------------------------------
1. Aldrin.......................... GC..................... 617, 608.3........... 6630 B-2007 & C-2007. D3086-90, D5812-96 See footnote,\3\ p.
(02). 7; See footnote,\4\
O-3104-83; See
footnote,\8\ 3M0222.
GC/MS.................. 625.1................ 6410 B-2000..........
2. Ametryn......................... GC..................... 507, 619............. ..................... ..................... See footnote,\3\ p.
83; See footnote,\9\
O-3106-93; See
footnote,\6\ p. S68.
GC/MS.................. 525.2, 625.1......... ..................... ..................... See footnote,\14\ O-
1121-91.
3. Aminocarb....................... TLC.................... ..................... ..................... ..................... See footnote,\3\ p.
94; See footnote,\6\
p. S60.
HPLC................... 632..................
4. Atraton......................... GC..................... 619.................. ..................... ..................... See footnote,\3\ p.
83; See footnote,\6\
p. S68.
GC/MS.................. 625.1................
5. Atrazine........................ GC..................... 507, 619, 608.3...... ..................... ..................... See footnote,\3\ p.
83; See footnote,\6\
p. S68; See
footnote,\9\ O-3106-
93.
HPLC/MS................ ..................... ..................... ..................... See footnote,\12\ O-
2060-01.
GC/MS.................. 525.1, 525.2, 625.1.. ..................... ..................... See footnote,\11\ O-
1126-95.
6. Azinphos methyl................. GC..................... 614, 622, 1657....... ..................... ..................... See footnote,\3\ p.
25; See footnote,\6\
p. S51.
GC/MS.................. 625.1................ ..................... ..................... See footnote,\11\ O-
1126-95.
7. Barban.......................... TLC.................... ..................... ..................... ..................... See footnote,\3\ p.
104; See
footnote,\6\ p. S64.
HPLC................... 632..................
GC/MS.................. 625.1................
8. [alpha]-BHC..................... GC..................... 617, 608.3........... 6630 B-2007 & C-2007. D3086-90, D5812- See footnote,\3\ p.
96(02). 7; See footnote,\8\
3M0222.
GC/MS.................. 625.1 \5\............ 6410 B-2000.......... ..................... See footnote,\11\ O-
1126-95.
9. [beta]-BHC...................... GC..................... 617, 608.3........... 6630 B-2007 & C-2007. D3086-90, D5812- See footnote,\8\
96(02). 3M0222.
GC/MS.................. 625.1................ 6410 B-2000..........
10. [delta]-BHC.................... GC..................... 617, 608.3........... 6630 B-2007 & C-2007. D3086-90, D5812- See footnote,\8\
96(02). 3M0222.
[[Page 40]]
GC/MS.................. 625.1................ 6410 B-2000..........
11. [gamma]-BHC (Lindane).......... GC..................... 617, 608.3........... 6630 B-2007 & C-2007. D3086-90, D5812- See footnote,\3\ p.
96(02). 7; See footnote,\4\
O-3104-83; See
footnote,\8\ 3M0222.
GC/MS.................. 625.1 \5\............ 6410 B-2000.......... ..................... See footnote,\11\ O-
1126-95.
12. Captan......................... GC..................... 617, 608.3........... 6630 B-2007.......... D3086-90, D5812- See footnote,\3\ p.
96(02). 7.
13. Carbaryl....................... TLC.................... ..................... ..................... ..................... See footnote,\3\ p.
94, See footnote,\6\
p. S60.
HPLC................... 531.1, 632...........
HPLC/MS................ 553.................. ..................... ..................... See footnote,\12\ O-
2060-01.
GC/MS.................. 625.1................ ..................... ..................... See footnote,\11\ O-
1126-95.
14. Carbophenothion................ GC..................... 617, 608.3........... 6630 B-2007.......... ..................... See footnote,\4\ page
27; See footnote,\6\
p. S73.
GC/MS.................. 625.1................
15. Chlordane...................... GC..................... 617, 608.3........... 6630 B-2007 & C-2007. D3086-90, D5812- See footnote,\3\ p.
96(02). 7; See footnote,\4\
O-3104-83; See
footnote,\8\ 3M0222.
GC/MS.................. 625.1................ 6410 B-2000..........
16. Chloropropham.................. TLC.................... ..................... ..................... ..................... See footnote,\3\ p.
104; See
footnote,\6\ p. S64.
HPLC................... 632..................
GC/MS.................. 625.1................
17. 2,4-D.......................... GC..................... 615.................. 6640 B-2006.......... ..................... See footnote,\3\ p.
115; See
footnote,\4\ O-3105-
83.
HPLC/MS................ ..................... ..................... ..................... See footnote,\12\ O-
2060-01.
18. 4,4[min]-DDD................... GC..................... 617, 608.3........... 6630 B-2007 & C-2007. D3086-90, D5812- See footnote,\3\ p.
96(02). 7; See footnote,\4\
O-3105-83; See
footnote,\8\ 3M0222.
GC/MS.................. 625.1................ 6410 B-2000..........
19. 4,4[min]-DDE................... GC..................... 617, 608.3........... 6630 B-2007 & C-2007. D3086-90, D5812- See footnote,\3\ p.
96(02). 7; See footnote,\4\
O-3104-83; See
footnote,\8\ 3M0222.
GC/MS.................. 625.1................ 6410 B-2000.......... ..................... See footnote,\11\ O-
1126-95.
20. 4,4[min]-DDT................... GC..................... 617, 608.3........... 6630 B-2007 & C-2007. D3086-90, D5812- See footnote,\3\ p.
96(02). 7; See footnote,\4\
O-3104-83; See
footnote,\8\ 3M0222.
GC/MS.................. 625.1................ 6410 B-2000..........
21. Demeton-O...................... GC..................... 614, 622............. ..................... ..................... See footnote,\3\ p.
25; See footnote,\6\
p. S51.
[[Page 41]]
GC/MS.................. 625.1................
22. Demeton-S...................... GC..................... 614, 622............. ..................... ..................... See footnote,\3\ p.
25; See footnote,\6\
p. S51.
GC/MS.................. 625.1................
23. Diazinon....................... GC..................... 507, 614, 622, 1657.. ..................... ..................... See footnote,\3\ p.
25; See footnote,\4\
O-3104-83; See
footnote,\6\ p. S51.
GC/MS.................. 525.2, 625.1......... ..................... ..................... See footnote,\11\ O-
1126-95.
24. Dicamba........................ GC..................... 615.................. ..................... ..................... See footnote,\3\ p.
115.
HPLC/MS................ ..................... ..................... ..................... See footnote,\12\ O-
2060-01.
25. Dichlofenthion................. GC..................... 622.1................ ..................... ..................... See footnote,\4\ page
27; See footnote,\6\
p. S73.
26. Dichloran...................... GC..................... 608.2, 617, 608.3.... 6630 B-2007.......... ..................... See footnote,\3\ p.
7.
27. Dicofol........................ GC..................... 617, 608.3........... ..................... ..................... See footnote,\4\ O-
3104-83.
28. Dieldrin....................... GC..................... 617, 608.3........... 6630 B-2007 & C-2007. D3086-90, D5812- See footnote,\3\ p.
96(02). 7; See footnote,\4\
O-3104-83; See
footnote,\8\ 3M0222.
GC/MS.................. 625.1................ 6410 B-2000.......... ..................... See footnote,\11\ O-
1126-95.
29. Dioxathion..................... GC..................... 614.1, 1657.......... ..................... ..................... See footnote,\4\ page
27; See footnote,\6\
p. S73.
30. Disulfoton..................... GC..................... 507, 614, 622, 1657.. ..................... ..................... See footnote,\3\ p.
25; See footnote,\6\
p. S51.
GC/MS.................. 525.2, 625.1......... ..................... ..................... See footnote,\11\ O-
1126-95.
31. Diuron......................... TLC.................... ..................... ..................... ..................... See footnote,\3\ p.
104; See
footnote,\6\ p. S64.
HPLC................... 632..................
HPLC/MS................ 553.................. ..................... ..................... See footnote,\12\ O-
2060-01.
32. Endosulfan I................... GC..................... 617, 608.3........... 6630 B-2007 & C-2007. D3086-90, D5812- See footnote,\3\ p.
96(02). 7; See footnote,\4\
O-3104-83; See
footnote,\8\
3M0222).
GC/MS.................. 625.1 \5\............ 6410 B-2000.......... ..................... See footnote,\13\ O-
2002-01.
33. Endosulfan II.................. GC..................... 617, 608.3........... 6630 B-2007 & C-2007. D3086-90, D5812- See footnote,\3\ p.
96(02). 7; See footnote,\8\
3M0222.
GC/MS.................. 625.1 \5\............ 6410 B-2000.......... ..................... See footnote,\13\ O-
2002-01.
34. Endosulfan Sulfate............. GC..................... 617, 608.3........... 6630 C-2007.......... ..................... See footnote,\8\
3M0222.
GC/MS.................. 625.1................ 6410 B-2000..........
35. Endrin......................... GC..................... 505, 508, 617, 1656, 6630 B-2007 & C-2007. D3086-90, D5812- See footnote,\3\ p.
608.3. 96(02). 7; See footnote,\4\
O-3104-83; See
footnote,\8\ 3M0222.
GC/MS.................. 525.1, 525.2, 6410 B-2000..........
625.1\5\.
36. Endrin aldehyde................ GC..................... 617, 608.3........... 6630 C-2007.......... ..................... See footnote,\8\
3M0222.
GC/MS.................. 625.1................
37. Ethion......................... GC..................... 614, 614.1, 1657..... ..................... ..................... See footnote,\4\ page
27; See footnote,\6\
p. S73.
[[Page 42]]
GC/MS.................. 625.1................ ..................... ..................... See footnote,\13\ O-
2002-01.
38. Fenuron........................ TLC.................... ..................... ..................... ..................... See footnote,\3\ p.
104; See
footnote,\6\ p. S64.
HPLC................... 632..................
HPLC/MS................ ..................... ..................... ..................... See footnote,\12\ O-
2060-01.
39. Fenuron-TCA.................... TLC.................... ..................... ..................... ..................... See footnote,\3\ p.
104; See
footnote,\6\ p. S64.
HPLC................... 632..................
40. Heptachlor..................... GC..................... 505, 508, 617, 1656, 6630 B-2007 & C-2007. D3086-90, D5812- See footnote,\3\ p.
608.3. 96(02). 7; See footnote,\4\
O-3104-83; See
footnote,\8\ 3M0222.
GC/MS.................. 525.1, 525.2, 625.1.. 6410 B-2000..........
41. Heptachlor epoxide............. GC..................... 617, 608.3........... 6630 B-2007 & C-2007. D3086-90, D5812- See footnote,\3\ p.
96(02). 7; See footnote,\4\
O-3104-83; See
footnote,\6\ p. S73;
See footnote,\8\
3M0222.
GC/MS.................. 625.1................ 6410 B-2000..........
42. Isodrin........................ GC..................... 617, 608.3........... 6630 B-2007 & C-2007. ..................... See footnote,\4\ O-
3104-83; See
footnote,\6\ p. S73.
GC/MS.................. 625.1................
43. Linuron........................ GC..................... ..................... ..................... ..................... See footnote,\3\ p.
104; See
footnote,\6\ p. S64.
HPLC................... 632..................
HPLC/MS................ 553.................. ..................... ..................... See footnote,\12\ O-
2060-01.
GC/MS.................. ..................... ..................... ..................... See footnote,\11\ O-
1126-95.
44. Malathion...................... GC..................... 614, 1657............ 6630 B-2007.......... ..................... See footnote,\3\ p.
25; See footnote,\6\
p. S51.
GC/MS.................. 625.1................ ..................... ..................... See footnote,\11\ O-
1126-95.
45. Methiocarb..................... TLC.................... ..................... ..................... ..................... See footnote,\3\ p.
94; See footnote,\6\
p. S60.
HPLC................... 632..................
HPLC/MS................ ..................... ..................... ..................... See footnote,\12\ O-
2060-01.
46. Methoxychlor................... GC..................... 505, 508, 608.2, 617, 6630 B-2007 & C-2007. D3086-90, D5812- See footnote,\3\ p.
1656, 608.3. 96(02). 7; See footnote,\4\
O-3104-83; See
footnote,\8\ 3M0222.
GC/MS.................. 525.1, 525.2, 625.1.. ..................... ..................... See footnote,\11\ O-
1126-95.
47. Mexacarbate.................... TLC.................... ..................... ..................... ..................... See footnote,\3\ p.
94; See footnote,\6\
p. S60.
HPLC................... 632..................
GC/MS.................. 625.1................
[[Page 43]]
48. Mirex.......................... GC..................... 617, 608.3........... 6630 B-2007 & C-2007. D3086-90, D5812- See footnote,\3\ p.
96(02). 7; See footnote,\4\
O-3104-83.
GC/MS.................. 625.1................
49. Monuron........................ TLC.................... ..................... ..................... ..................... See footnote,\3\ p.
104; See
footnote,\6\ p. S64.
HPLC................... 632..................
50. Monuron-TCA.................... TLC.................... ..................... ..................... ..................... See footnote,\3\ p.
104; See
footnote,\6\ p. S64.
HPLC................... 632..................
51. Neburon........................ TLC.................... ..................... ..................... ..................... See footnote,\3\ p.
104; See
footnote,\6\ p. S64.
HPLC................... 632..................
HPLC/MS................ ..................... ..................... ..................... See footnote,\12\ O-
2060-01.
52. Parathion methyl............... GC..................... 614, 622, 1657....... 6630 B-2007.......... ..................... See footnote,\4\ page
27; See footnote,\3\
p. 25.
GC/MS.................. 625.1................ ..................... ..................... See footnote,\11\ O-
1126-95.
53. Parathion ethyl................ GC..................... 614.................. 6630 B-2007.......... ..................... See footnote,\4\ page
27; See footnote,\3\
p. 25.
GC/MS.................. ..................... ..................... ..................... See footnote,\11\ O-
1126-95.
54. PCNB........................... GC..................... 608.1, 617, 608.3.... 6630 B-2007 & C-2007. D3086-90, D5812- See footnote,\3\ p.
96(02). 7.
55. Perthane....................... GC..................... 617, 608.3........... ..................... D3086-90, D5812- See footnote,\4\ O-
96(02). 3104-83.
56. Prometon....................... GC..................... 507, 619............. ..................... ..................... See footnote,\3\ p.
83; See footnote,\6\
p. S68; See
footnote,\9\ O-3106-
93.
GC/MS.................. 525.2, 625.1......... ..................... ..................... See footnote,\11\ O-
1126-95.
57. Prometryn...................... GC..................... 507, 619............. ..................... ..................... See footnote,\3\ p.
83; See footnote,\6\
p. S68; See
footnote,\9\ O-3106-
93.
GC/MS.................. 525.1, 525.2, 625.1.. ..................... ..................... See footnote,\13\ O-
2002-01.
58. Propazine...................... GC..................... 507, 619, 1656, 608.3 ..................... ..................... See footnote,\3\ p.
83; See footnote,\6\
p. S68; See
footnote,\9\ O-3106-
93.
GC/MS.................. 525.1, 525.2, 625.1..
59. Propham........................ TLC.................... ..................... ..................... ..................... See footnote,\3\ p.
104; See
footnote,\6\ p. S64.
HPLC................... 632..................
HPLC/MS................ ..................... ..................... ..................... See footnote,\12\ O-
2060-01.
60. Propoxur....................... TLC.................... ..................... ..................... ..................... See footnote,\3\ p.
94; See footnote,\6\
p. S60.
HPLC................... 632..................
61. Secbumeton..................... TLC.................... ..................... ..................... ..................... See footnote,\3\ p.
83; See footnote,\6\
p. S68.
[[Page 44]]
GC..................... 619..................
62. Siduron........................ TLC.................... ..................... ..................... ..................... See footnote,\3\ p.
104; See
footnote,\6\ p. S64.
HPLC................... 632..................
HPLC/MS................ ..................... ..................... ..................... See footnote,\12\ O-
2060-01.
63. Simazine....................... GC..................... 505, 507, 619, 1656, ..................... ..................... See footnote,\3\ p.
608.3. 83; See footnote,\6\
p. S68; See
footnote,\9\ O-3106-
93.
GC/MS.................. 525.1, 525.2, 625.1.. ..................... ..................... See footnote,\11\ O-
1126-95.
64. Strobane....................... GC..................... 617, 608.3........... 6630 B-2007 & C-2007. ..................... See footnote,\3\ p.
7.
65. Swep........................... TLC.................... ..................... ..................... ..................... See footnote,\3\ p.
104; See
footnote,\6\ p. S64.
HPLC................... 632..................
66. 2,4,5-T........................ GC..................... 615.................. 6640 B-2006.......... ..................... See footnote,\3\ p.
115; See
footnote,\4\ O-3105-
83.
67. 2,4,5-TP (Silvex).............. GC..................... 615.................. 6640 B-2006.......... ..................... See footnote,\3\ p.
115; See
footnote,\4\ O-3105-
83.
68. Terbuthylazine................. GC..................... 619, 1656, 608.3..... ..................... ..................... See footnote,\3\ p.
83; See footnote,\6\
p. S68.
GC/MS.................. ..................... ..................... ..................... See footnote,\13\ O-
2002-01.
69. Toxaphene...................... GC..................... 505, 508, 617, 1656, 6630 B-2007 & C-2007. D3086-90, D5812- See footnote,\3\ p.
608.3. 96(02). 7; See footnote; \8\
See footnote,\4\ O-
3105-83.
GC/MS.................. 525.1, 525.2, 625.1.. 6410 B-2000..........
70. Trifluralin.................... GC..................... 508, 617, 627, 1656, 6630 B-2007.......... ..................... See footnote,\3\ p.
608.3. 7; See footnote,\9\
O-3106-93.
GC/MS.................. 525.2, 625.1......... ..................... ..................... See footnote,\11\ O-
1126-95.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Table ID notes:
\1\ Pesticides are listed in this table by common name for the convenience of the reader. Additional pesticides may be found under Table IC of this
section, where entries are listed by chemical name.
\2\ The standardized test procedure to be used to determine the method detection limit (MDL) for these test procedures is given at appendix B of this
part, Definition and Procedure for the Determination of the Method Detection Limit.
\3\ Methods for Benzidine, Chlorinated Organic Compounds, Pentachlorophenol and Pesticides in Water and Wastewater. September 1978. U.S. EPA. This EPA
publication includes thin-layer chromatography (TLC) methods.
\4\ Methods for the Determination of Organic Substances in Water and Fluvial Sediments, Techniques of Water-Resources Investigations of the U.S.
Geological Survey, Book 5, Chapter A3. 1987. USGS.
\5\ The method may be extended to include [alpha]-BHC, [gamma]-BHC, endosulfan I, endosulfan II, and endrin. However, when they are known to exist,
Method 608.3 is the preferred method.
\6\ Selected Analytical Methods Approved and Cited by the United States Environmental Protection Agency, Supplement to the 15th Edition of Standard
Methods for the Examination of Water and Wastewater. 1981. American Public Health Association (APHA).
[[Page 45]]
\7\ Each analyst must make an initial, one-time, demonstration of their ability to generate acceptable precision and accuracy with Methods 608.3 and
625.1 in accordance with procedures given in Section 8.2 of each of these methods. Additionally, each laboratory, on an on-going basis, must spike and
analyze 5% of all samples analyzed with Method 608.3 or 5% of all samples analyzed with Method 625.1 to monitor and evaluate laboratory data quality
in accordance with Sections 8.3 and 8.4 of these methods. When the recovery of any parameter falls outside the warning limits, the analytical results
for that parameter in the unspiked sample are suspect. The results should be reported, but cannot be used to demonstrate regulatory compliance. These
quality control requirements also apply to the Standard Methods, ASTM Methods, and other methods cited.
\8\ Organochlorine Pesticides and PCBs in Wastewater Using Empore\TM\ Disk. Revised October 28, 1994. 3M Corporation.
\9\ Method O-3106-93 is in Open File Report 94-37, Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory--Determination of
Triazine and Other Nitrogen-Containing Compounds by Gas Chromatography With Nitrogen Phosphorus Detectors. 1994. USGS.
\10\ EPA Methods 608.1, 608.2, 614, 614.1, 615, 617, 619, 622, 622.1, 627, and 632 are found in Methods for the Determination of Nonconventional
Pesticides in Municipal and Industrial Wastewater, EPA 821-R-92-002, April 1992, U.S. EPA. EPA Methods 505, 507, 508, 525.1, 531.1 and 553 are in
Methods for the Determination of Nonconventional Pesticides in Municipal and Industrial Wastewater, Volume II, EPA 821-R-93-010B, 1993, U.S. EPA. EPA
Method 525.2 is in Determination of Organic Compounds in Drinking Water by Liquid-Solid Extraction and Capillary Column Gas Chromatography/Mass
Spectrometry, Revision 2.0, 1995, U.S. EPA. EPA methods 1656 and 1657 are in Methods for the Determination of Nonconventional Pesticides in Municipal
and Industrial Wastewater, Volume I, EPA 821-R-93-010A, 1993, U.S. EPA. Methods 608.3 and 625.1 are available at https://www.epa.gov/cwa-methods/
approved-cwa-test-methods-organic-compounds.
\11\ Method O-1126-95 is in Open-File Report 95-181, Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory--Determination
of pesticides in water by C-18 solid-phase extraction and capillary-column gas chromatography/mass spectrometry with selected-ion monitoring. 1995.
USGS.
\12\ Method O-2060-01 is in Water-Resources Investigations Report 01-4134, Methods of Analysis by the U.S. Geological Survey National Water Quality
Laboratory--Determination of Pesticides in Water by Graphitized Carbon-Based Solid-Phase Extraction and High-Performance Liquid Chromatography/Mass
Spectrometry. 2001. USGS.
\13\ Method O-2002-01 is in Water-Resources Investigations Report 01-4098, Methods of Analysis by the U.S. Geological Survey National Water Quality
Laboratory--Determination of moderate-use pesticides in water by C-18 solid-phase extraction and capillary-column gas chromatography/mass
spectrometry. 2001. USGS.
\14\ Method O-1121-91 is in Open-File Report 91-519, Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory--Determination
of organonitrogen herbicides in water by solid-phase extraction and capillary-column gas chromatography/mass spectrometry with selected-ion
monitoring. 1992. USGS.
Table IE--List of Approved Radiologic Test Test Procedures
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Reference (method number or page)
--------------------------------------------------------------------------------------------------------------------------------------
Parameter and units Method Standard Methods 18th,
EPA \1\ 19th, 20th Ed. Standard Methods Online ASTM USGS \2\
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1. Alpha-Total, pCi per liter..... Proportional or 900.0................ 7110 B.................... 7110 B-00................. D1943-90, 96.............. pp. 75 and 78 \3\
scintillation
counter.
2. Alpha-Counting error, pCi per Proportional or Appendix B........... 7110 B.................... 7110 B-00................. D1943-90, 96.............. p. 79
liter. scintillation
counter.
3. Beta-Total, pCi per liter...... Proportional counter. 900.0................ 7110 B.................... 7110 B-00................. D1890-90, 96.............. pp. 75 and 78 \3\
4. Beta-Counting error, pCi....... Proportional counter. Appendix B........... 7110 B.................... 7110 B-00................. D1890-90, 96.............. p. 79
5. (a) Radium Total pCi per liter. Proportional counter. 903.0................ 7500-Ra B................. 7500-Ra B-01.............. D2460-90, 97..............
(b) Ra, pCi per liter.............
Scintillation counter 903.1................ 7500-Ra C................. 7500-Ra C-01.............. D3454-91, 97.............. p. 81
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Prescribed Procedures for Measurement of Radioactivity in Drinking Water, EPA-600/4-80-032 (1980), U.S. Environmental Protection Agency, August 1980.
\2\ Fishman, M. J. and Brown, Eugene, ``Selected Methods of the U.S. Geological Survey of Analysis of Wastewaters,'' U.S. Geological Survey, Open-File Report 76-177 (1976).
\3\ The method found on p. 75 measures only the dissolved portion while the method on p. 78 measures only the suspended portion. Therefore, the two results must be added to obtain the
``total.''
[[Page 46]]
Table IF--List of Approved Methods for Pharmaceutical Pollutants
----------------------------------------------------------------------------------------------------------------
CAS registry
Pharmaceuticals pollutants No. Analytical method number
----------------------------------------------------------------------------------------------------------------
Acetonitrile....................... 75-05-8 1666/1671/D3371/D3695/624.1
n-Amyl acetate..................... 628-63-7 1666/D3695
n-Amyl alcohol..................... 71-41-0 1666/D3695
Benzene............................ 71-43-2 D4763/D3695/502.2/524.2/624.1
n-Butyl-acetate.................... 123-86-4 1666/D3695
tert-Butyl alcohol................. 75-65-0 1666/624.1
Chlorobenzene...................... 108-90-7 502.2/524.2/624.1
Chloroform......................... 67-66-3 502.2/524.2/551/624.1
o-Dichlorobenzene.................. 95-50-1 1625C/502.2/524.2/624.1
1,2-Dichloroethane................. 107-06-2 D3695/502.2/524.2/624.1
Diethylamine....................... 109-89-7 1666/1671
Dimethyl sulfoxide................. 67-68-5 1666/1671
Ethanol............................ 64-17-5 1666/1671/D3695/624.1
Ethyl acetate...................... 141-78-6 1666/D3695/624.1
n-Heptane.......................... 142-82-5 1666/D3695
n-Hexane........................... 110-54-3 1666/D3695
Isobutyraldehyde................... 78-84-2 1666/1667
Isopropanol........................ 67-63-0 1666/D3695
Isopropyl acetate.................. 108-21-4 1666/D3695
Isopropyl ether.................... 108-20-3 1666/D3695
Methanol........................... 67-56-1 1666/1671/D3695/624.1
Methyl Cellosolve[supreg] (2- 109-86-4 1666/1671
Methoxy ethanol).
Methylene chloride................. 75-09-2 502.2/524.2/624.1
Methyl formate..................... 107-31-3 1666
4-Methyl-2-pentanone (MIBK)........ 108-10-1 1624C/1666/D3695/D4763/524.2/624.1
Phenol............................. 108-95-2 D4763
n-Propanol......................... 71-23-8 1666/1671/D3695/624.1
2-Propanone (Acetone).............. 67-64-1 D3695/D4763/524.2/624.1
Tetrahydrofuran.................... 109-99-9 1666/524.2/624.1
Toluene............................ 108-88-3 D3695/D4763/502.2/524.2/624.1
Triethlyamine...................... 121-44-8 1666/1671
Xylenes............................ (Note 1) 1624C/1666/624.1
----------------------------------------------------------------------------------------------------------------
Table IF note:
\1\ 1624C: m-xylene 108-38-3, o,p-xylene, E-14095 (Not a CAS number; this is the number provided in the
Environmental Monitoring Methods Index [EMMI] database.); 1666: m,p-xylene 136777-61-2, o-xylene 95-47-6.
Table IG--Test Methods for Pesticide Active Ingredients
[40 CFR part 455]
------------------------------------------------------------------------
EPA analytical
EPA survey code Pesticide name CAS No. method No.(s)
\3\
------------------------------------------------------------------------
8................... Triadimefon..... 43121-43-3 507/633/525.1/
525.2/1656/
625.1.
12.................. Dichlorvos...... 62-73-7 1657/507/622/
525.1/525.2/
625.1.
16.................. 2,4-D; 2,4-D 94-75-7 1658/515.1/615/
Salts and 515.2/555.
Esters [2,4-
Dichloro-
phenoxyacetic
acid].
17.................. 2,4-DB; 2,4-DB 94-82-6 1658/515.1/615/
Salts and 515.2/555.
Esters [2,4-
Dichlorophenoxy
butyric acid].
22.................. Mevinphos....... 7786-34-7 1657/507/622/
525.1/525.2/
625.1.
25.................. Cyanazine....... 21725-46-2 629/507/608.3/
625.1.
26.................. Propachlor...... 1918-16-7 1656/508/608.1/
525.1/525.2/
608.3/625.1.
27.................. MCPA; MCPA Salts 94-74-6 1658/615/555.
and Esters.
[2-Methyl-4-
chlorophenoxyac
etic acid].
30.................. Dichlorprop; 120-36-5 1658/515.1/615/
Dichlorprop 515.2/555.
Salts and
Esters [2-(2,4-
Dichlorophenoxy
) propionic
acid].
31.................. MCPP; MCPP Salts 93-65-2 1658/615/555.
and Esters [2-
(2-Methyl-4-
chlorophenoxy)
propionic acid].
35.................. TCMTB [2- 21564-17-0 637.
(Thiocyanomethy
lthio) benzo-
thiazole].
39.................. Pronamide....... 23950-58-5 525.1/525.2/507/
633.1/625.1.
41.................. Propanil........ 709-98-8 632.1/1656/
608.3.
45.................. Metribuzin...... 21087-64-9 507/633/525.1/
525.2/1656/
608.3/625.1.
52.................. Acephate........ 30560-19-1 1656/1657/608.3.
53.................. Acifluorfen..... 50594-66-6 515.1/515.2/555.
54.................. Alachlor........ 15972-60-8 505/507/645/
525.1/525.2/
1656/608.3/
625.1.
55.................. Aldicarb........ 116-06-3 531.1.
58.................. Ametryn......... 834-12-8 507/619/525.2/
625.1.
60.................. Atrazine........ 1912-24-9 505/507/619/
525.1/525.2/
1656/ 608.3/
625.1.
62.................. Benomyl......... 17804-35-2 631.
[[Page 47]]
68.................. Bromacil; 314-40-9 507/633/525.1/
Bromacil Salts 525.2/1656/
and Esters. 608.3/625.1.
69.................. Bromoxynil...... 1689-84-5 1625/1661/625.1.
69.................. Bromoxynil 1689-99-2 1656/608.3.
Octanoate.
70.................. Butachlor....... 23184-66-9 507/645/525.1/
525.2/1656/
608.3/625.1.
73.................. Captafol........ 2425-06-1 1656/608.3/
625.1.
75.................. Carbaryl [Sevin] 63-25-2 531.1/632/553/
625.1.
76.................. Carbofuran...... 1563-66-2 531.1/632/625.1.
80.................. Chloroneb....... 2675-77-6 1656/508/608.1/
525.1/525.2/
608.3/625.1.
82.................. Chlorothalonil.. 1897-45-6 508/608.2/525.1/
525.2/1656/
608.3/625.1.
84.................. Stirofos........ 961-11-5 1657/507/622/
525.1/525.2/
625.1.
86.................. Chlorpyrifos.... 2921-88-2 1657/508/622/
625.1.
90.................. Fenvalerate..... 51630-58-1 1660.
103................. Diazinon........ 333-41-5 1657/507/614/622/
525.2/625.1.
107................. Parathion methyl 298-00-0 1657/614/622/
625.1.
110................. DCPA [Dimethyl 1861-32-1 508/608.2/525.1/
2,3,5,6- 525.2/515.1 \2\/
tetrachloro- 515.2 \2\/1656/
terephthalate]. 608.3/625.1.
112................. Dinoseb......... 88-85-7 1658/515.1/615/
515.2/555/
625.1.
113................. Dioxathion...... 78-34-2 1657/614.1.
118................. Nabonate 138-93-2 630.1.
[Disodium
cyanodithio-
imidocarbonate].
119................. Diuron.......... 330-54-1 632/553.
123................. Endothall....... 145-73-3 548/548.1.
124................. Endrin.......... 72-20-8 1656/505/508/617/
525.1/525.2/
608.3/625.1.
125................. Ethalfluralin... 55283-68-6 1656/627/608.3
See footnote 1.
126................. Ethion.......... 563-12-2 1657/614/614.1/
625.1.
127................. Ethoprop........ 13194-48-4 1657/507/622/
525.1/525.2/
625.1.
132................. Fenarimol....... 60168-88-9 507/633.1/525.1/
525.2/1656/
608.3/625.1.
133................. Fenthion........ 55-38-9 1657/622/625.1.
138................. Glyphosate [N- 1071-83-6 547.
(Phosphonomethy
l) glycine].
140................. Heptachlor...... 76-44-8 1656/505/508/617/
525.1/525.2/
608.3/625.1.
144................. Isopropalin..... 33820-53-0 1656/627/608.3.
148................. Linuron......... 330-55-2 553/632.
150................. Malathion....... 121-75-5 1657/614/625.1.
154................. Methamidophos... 10265-92-6 1657.
156................. Methomyl........ 16752-77-5 531.1/632.
158................. Methoxychlor.... 72-43-5 1656/505/508/
608.2/617/525.1/
525.2/608.3/
625.1.
172................. Nabam........... 142-59-6 630/630.1.
173................. Naled........... 300-76-5 1657/622/625.1.
175................. Norflurazon..... 27314-13-2 507/645/525.1/
525.2/1656/
608.3/625.1.
178................. Benfluralin..... 1861-40-1 1656/627/608.3
See footnote 1.
182................. Fensulfothion... 115-90-2 1657/622/625.1.
183................. Disulfoton...... 298-04-4 1657/507/614/622/
525.2/625.1.
185................. Phosmet......... 732-11-6 1657/622.1/
625.1.
186................. Azinphos Methyl. 86-50-0 1657/614/622/
625.1.
192................. Organo-tin 12379-54-3 Ind-01/200.7/
pesticides. 200.9.
197................. Bolstar......... 35400-43-2 1657/622.
203................. Parathion....... 56-38-2 1657/614/625.1.
204................. Pendimethalin... 40487-42-1 1656.
205................. Pentachloronitro 82-68-8 1656/608.1/617/
benzene. 608.3/625.1.
206................. Pentachloropheno 87-86-5 1625/515.2/555/
l. 515.1/525.1/
525.2/625.1.
208................. Permethrin...... 52645-53-1 608.2/508/525.1/
525.2/1656/1660/
608.3 \4\/625.1
\4\.
212................. Phorate......... 298-02-2 1657/622/625.1.
218................. Busan 85 128-03-0 630/630.1.
[Potassium
dimethyldithioc
arbamate].
219................. Busan 40 51026-28-9 630/630.1.
[Potassium N-
hydroxymethyl-N-
methyldithiocar
bamate].
220................. KN Methyl 137-41-7 630/630.1.
[Potassium N-
methyl-
dithiocarbamate
].
223................. Prometon........ 1610-18-0 507/619/525.2/
625.1.
224................. Prometryn....... 7287-19-6 507/619/525.1/
525.2/625.1.
226................. Propazine....... 139-40-2 507/619/525.1/
525.2/1656/
608.3/625.1.
230................. Pyrethrin I..... 121-21-1 1660.
232................. Pyrethrin II.... 121-29-9 1660.
236................. DEF [S,S,S- 78-48-8 1657.
Tributyl
phosphorotrithi
oate].
239................. Simazine........ 122-34-9 505/507/619/
525.1/525.2/
1656/608.3/
625.1.
241................. Carbam-S [Sodium 128-04-1 630/630.1.
dimethyldithio-
carbamate].
[[Page 48]]
243................. Vapam [Sodium 137-42-8 630/630.1.
methyldithiocar
bamate].
252................. Tebuthiuron..... 34014-18-1 507/525.1/525.2/
625.1.
254................. Terbacil........ 5902-51-2 507/633/525.1/
525.2/1656/
608.3/625.1.
255................. Terbufos........ 13071-79-9 1657/507/614.1/
525.1/525.2/
625.1.
256................. Terbuthylazine.. 5915-41-3 619/1656/608.3.
257................. Terbutryn....... 886-50-0 507/619/525.1/
525.2/625.1.
259................. Dazomet......... 533-74-4 630/630.1/1659.
262................. Toxaphene....... 8001-35-2 1656/505/508/617/
525.1/525.2/
608.3/625.1.
263................. Merphos 150-50-5 1657/507/525.1/
[Tributyl 525.2/622/
phosphorotrithi 625.1.
oate].
264................. Trifluralin \1\. 1582-09-8 1656/508/617/627/
525.2/608.3/
625.1.
268................. Ziram [Zinc 137-30-4 630/630.1.
dimethyldithioc
arbamate].
------------------------------------------------------------------------
Table IG notes:
\1\ Monitor and report as total Trifluralin.
\2\ Applicable to the analysis of DCPA degradates.
\3\ EPA Methods 608.1 through 645, 1645 through 1661, and Ind-01 are
available in Methods for the Determination of Nonconventional
Pesticides in Municipal and Industrial Wastewater, Volume I, EPA 821-R-
93-010A, Revision I, August 1993, U.S. EPA. EPA Methods 200.9 and 505
through 555 are available in Methods for the Determination of
Nonconventional Pesticides in Municipal and Industrial Wastewater,
Volume II, EPA 821-R-93-010B, August 1993, U.S. EPA. The full text of
Methods 608.3, 625.1, and 1625 are provided at appendix A of this
part. The full text of Method 200.7 is provided at appendix C of this
part. Methods 608.3 and 625.1 are available at https://www.epa.gov/cwa-
methods/approved-cwa-test-methods-organic-compounds.
\4\ Permethrin is not listed within methods 608.3 and 625.1; however,
cis-permethrin and trans-permethrin are listed. Permethrin can be
calculated by adding the results of cis- and trans-permethrin.
[[Page 49]]
Table IH--List of Approved Microbiological Methods for Ambient Water
--------------------------------------------------------------------------------------------------------------------------------------------------------
Parameter and units Method \1\ EPA Standard methods AOAC, ASTM, USGS Other
--------------------------------------------------------------------------------------------------------------------------------------------------------
Bacteria
--------------------------------------------------------------------------------------------------------------------------------------------------------
1. Coliform (fecal), number per Most Probable Number p. 132 \3\.................. 9221 C E-2006.
100 mL or number per gram dry (MPN), 5 tube, 3
weight. dilution, or.
Membrane filter p. 124 \3\.................. 9222 D-2006 \ 27\... B-0050-85. \4\
(MF),\2\ single
step.
2. Coliform (fecal) in presence of MPN, 5 tube, 3 p. 132 \3\.................. 9221 C E-2006.
chlorine, number per 100 mL. dilution, or.
MF,\2\ single step p. 124 \3\.................. 9222 D-2006. \ 27\
\5\.
3. Coliform (total), number per MPN, 5 tube, 3 p. 114 \3\.................. 9221 B-2006.
100 mL. dilution, or.
MF,\2\ single step p. 108 \3\.................. 9222 B-2006......... B-0025-85. \4\
or two step.
4. Coliform (total), in presence MPN, 5 tube, 3 p. 114 \3\.................. 9221 B-2006.
of chlorine, number per 100 mL. dilution, or.
MF \2\ with p. 111 \3\.................. 9222 B-2006.
enrichment.
5. E. coli, number per 100 mL..... MPN,6 8 14 multiple ............................ 9221 B.2-2006/9221 F-
tube, or. 2006 11 13.
Multiple tube/ ............................ 9223 B-2004 \12\.... 991.15 \10\......... Colilert[supreg],12
multiple well, or. 16 Colilert-
18[supreg].12 15 16
MF,2 5 6 7 8 two 1103.1 \19\................. 9222 B-2006/9222 G- D-5392-93. \9\
step, or. 2006,\18\ 9213 D-
2007.
Single step......... 1603,\20\ 1604 \21\......... .................... .................... mColiBlue-
24[supreg].\17\
6. Fecal streptococci, number per MPN, 5 tube, 3 p. 139 \3\.................. 9230 B-2007.
100 mL. dilution, or.
MF \2\, or.......... p. 136 \3\.................. 9230 C-2007......... B-0055-85 \4\.......
Plate count......... p. 143. \3\
7. Enterococci, number per 100 mL. MPN,6 8 multiple ............................ 9230 D-2007......... D6503-99 \9\........ Enterolert[supreg].1
tube/multiple well, 2 22
or.
MF 2 5 6 7 8 two 1106.1 \23\................. 9230 C-2007......... D5259-92. \9\
step, or.
Single step, or..... 1600 \24\................... 9230 C-2007.
Plate count......... p. 143. \3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Protozoa
--------------------------------------------------------------------------------------------------------------------------------------------------------
8. Cryptosporidium................ Filtration/IMS/FA... 1622, \25\ 1623. \26\
[[Page 50]]
9. Giardia........................ Filtration/IMS/FA... 1623. \26\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Table IH notes:
\1\ The method must be specified when results are reported.
\2\ A 0.45-[micro]m membrane filter (MF) or other pore size certified by the manufacturer to fully retain organisms to be cultivated and to be free of
extractables which could interfere with their growth.
\3\ Microbiological Methods for Monitoring the Environment, Water, and Wastes. EPA/600/8-78/017. 1978. U.S. EPA.
\4\ U.S. Geological Survey Techniques of Water-Resource Investigations, Book 5, Laboratory Analysis, Chapter A4, Methods for Collection and Analysis of
Aquatic Biological and Microbiological Samples. 1989. USGS.
\5\ Because the MF technique usually yields low and variable recovery from chlorinated wastewaters, the Most Probable Number method will be required to
resolve any controversies.
\6\ Tests must be conducted to provide organism enumeration (density). Select the appropriate configuration of tubes/filtrations and dilutions/volumes
to account for the quality, character, consistency, and anticipated organism density of the water sample.
\7\ When the MF method has not been used previously to test waters with high turbidity, large numbers of noncoliform bacteria, or samples that may
contain organisms stressed by chlorine, a parallel test should be conducted with a multiple-tube technique to demonstrate applicability and
comparability of results.
\8\ To assess the comparability of results obtained with individual methods, it is suggested that side-by-side tests be conducted across seasons of the
year with the water samples routinely tested in accordance with the most current Standard Methods for the Examination of Water and Wastewater or EPA
alternate test procedure (ATP) guidelines.
\9\ Annual Book of ASTM Standards--Water and Environmental Technology. Section 11.02. 2000, 1999, 1996. ASTM International.
\10\ Official Methods of Analysis of AOAC International, 16th Edition, Volume I, Chapter 17. 1995. AOAC International.
\11\ The multiple-tube fermentation test is used in 9221B.2-2006. Lactose broth may be used in lieu of lauryl tryptose broth (LTB), if at least 25
parallel tests are conducted between this broth and LTB using the water samples normally tested, and this comparison demonstrates that the false-
positive rate and false-negative rate for total coliform using lactose broth is less than 10 percent. No requirement exists to run the completed phase
on 10 percent of all total coliform-positive tubes on a seasonal basis.
\12\ These tests are collectively known as defined enzyme substrate tests, where, for example, a substrate is used to detect the enzyme [beta]-
glucuronidase produced by E. coli.
\13\ After prior enrichment in a presumptive medium for total coliform using 9221B.2-2006, all presumptive tubes or bottles showing any amount of gas,
growth or acidity within 48 h 3 h of incubation shall be submitted to 9221F-2006. Commercially available EC-MUG media or EC
media supplemented in the laboratory with 50 [micro]g/mL of MUG may be used.
\14\ Samples shall be enumerated by the multiple-tube or multiple-well procedure. Using multiple-tube procedures, employ an appropriate tube and
dilution configuration of the sample as needed and report the Most Probable Number (MPN). Samples tested with Colilert[supreg] may be enumerated with
the multiple-well procedures, Quanti-Tray[supreg] or Quanti-Tray[supreg]/2000, and the MPN calculated from the table provided by the manufacturer.
\15\ Colilert-18[supreg] is an optimized formulation of the Colilert[supreg] for the determination of total coliforms and E. coli that provides results
within 18 h of incubation at 35 [deg]C, rather than the 24 h required for the Colilert[supreg] test, and is recommended for marine water samples.
\16\ Descriptions of the Colilert[supreg], Colilert-18[supreg], and Quanti-Tray[supreg] may be obtained from IDEXX Laboratories Inc.
\17\ A description of the mColiBlue24[supreg] test may be obtained from Hach Company.
\18\ Subject total coliform positive samples determined by 9222B-2006 or other membrane filter procedure to 9222G-2006 using NA-MUG media.
\19\ Method 1103.1: Escherichia coli (E. coli) in Water by Membrane Filtration Using membrane-Thermotolerant Escherichia coli Agar (mTEC), EPA-821-R-10-
002. March 2010. U.S. EPA.
\20\ Method 1603: Escherichia coli (E. coli) in Water by Membrane Filtration Using Modified membrane-Thermotolerant Escherichia coli Agar (Modified
mTEC), EPA-821-R-14-010. September 2014. U.S. EPA.
\21\ Preparation and use of MI agar with a standard membrane filter procedure is set forth in the article, Brenner et al. 1993. New Medium for the
Simultaneous Detection of Total Coliform and Escherichia coli in Water. Appl. Environ. Microbiol. 59:3534-3544 and in Method 1604: Total Coliforms and
Escherichia coli (E. coli) in Water by Membrane Filtration by Using a Simultaneous Detection Technique (MI Medium), EPA 821-R-02-024, September 2002,
U.S. EPA.
\22\ A description of the Enterolert[supreg] test may be obtained from IDEXX Laboratories Inc.
[[Page 51]]
\23\ Method 1106.1: Enterococci in Water by Membrane Filtration Using membrane-Enterococcus-Esculin Iron Agar (mE-EIA), EPA-821-R-09-015. December 2009.
U.S. EPA.
\24\ Method 1600: Enterococci in Water by Membrane Filtration Using membrane-Enterococcus Indoxyl-[beta]-D-Glucoside Agar (mEI), EPA-821-R-14-011.
September 2014. U.S. EPA.
\25\ Method 1622 uses a filtration, concentration, immunomagnetic separation of oocysts from captured material, immunofluorescence assay to determine
concentrations, and confirmation through vital dye staining and differential interference contrast microscopy for the detection of Cryptosporidium.
Method 1622: Cryptosporidium in Water by Filtration/IMS/FA, EPA-821-R-05-001. December 2005. U.S. EPA.
\26\ Method 1623 uses a filtration, concentration, immunomagnetic separation of oocysts and cysts from captured material, immunofluorescence assay to
determine concentrations, and confirmation through vital dye staining and differential interference contrast microscopy for the simultaneous detection
of Cryptosporidium and Giardia oocysts and cysts. Method 1623: Cryptosporidium and Giardia in Water by Filtration/IMS/FA. EPA-821-R-05-002. December
2005. U.S. EPA.
\27\ On a monthly basis, at least ten blue colonies from the medium must be verified using Lauryl Tryptose Broth and EC broth, followed by count
adjustment based on these results; and representative non-blue colonies should be verified using Lauryl Tryptose Broth. Where possible, verifications
should be done from randomized sample sources.
[[Page 52]]
(b) Certain material is incorporated by reference into this part
with the approval of the Director of the Federal Register under 5 U.S.C.
552(a) and 1 CFR part 51. All approved material is available for
inspection at EPA's Water Docket, EPA West, 1301 Constitution Avenue
NW., Room 3334, Washington, DC 20004, Telephone: 202-566-2426, and is
available from the sources listed below. It is also available for
inspection at the National Archives and Records Administration (NARA).
For information on the availability of this material at NARA, call 202-
741-6030, or go to: https://www.archives.gov/federal-register/cfr/ibr-
locations.html.
(1) Environmental Monitoring and Support Laboratory, U.S.
Environmental Protection Agency, Cincinnati OH (US EPA). Available at
http://water.epa.gov/scitech/methods/cwa/index.cfm or from: National
Technical Information Service, 5285 Port Royal Road, Springfield,
Virginia 22161
(i) Microbiological Methods for Monitoring the Environment, Water,
and Wastes. 1978. EPA/600/8-78/017, Pub. No. PB-290329/A.S.
(A) Part III Analytical Methodology, Section B Total Coliform
Methods, page 108. Table IA, Note 3; Table IH, Note 3.
(B) Part III Analytical Methodology, Section B Total Coliform
Methods, 2.6.2 Two-Step Enrichment Procedure, page 111. Table IA, Note
3; Table IH, Note 3.
(C) Part III Analytical Methodology, Section B Total Coliform
Methods, 4 Most Probable Number (MPN) Method, page 114. Table IA, Note
3; Table IH, Note 3.
(D) Part III Analytical Methodology, Section C Fecal Coliform
Methods, 2 Direct Membrane Filter (MF) Method, page 124. Table IA, Note
3; Table IH, Note 3.
(E) Part III, Analytical Methodology, Section C Fecal Coliform
Methods, 5 Most Probable Number (MPN) Method, page 132. Table IA, Note
3; Table IH, Note 3.
(F) Part III Analytical Methodology, Section D Fecal Streptococci, 2
Membrane Filter (MF) Method, page 136. Table IA, Note 3; Table IH, Note
3.
(G) Part III Analytical Methodology, Section D Fecal Streptococci, 4
Most Probable Number Method, page 139. Table IA, Note 3; Table IH, Note
3.
(H) Part III Analytical Methodology, Section D Fecal Streptococci, 5
Pour Plate Method, page 143. Table IA, Note 3; Table IH, Note 3.
(ii) [Reserved]
(2) Environmental Monitoring and Support Laboratory, U.S.
Environmental Protection Agency, Cincinnati OH (US EPA). Available at
http://water.epa.gov/scitech/methods/cwa/index.cfm.
(i) Method 300.1 (including Errata Cover Sheet, April 27, 1999),
Determination of Inorganic Ions in Drinking Water by Ion Chromatography,
Revision 1.0, 1997. Table IB, Note 52.
(ii) Method 551, Determination of Chlorination Disinfection
Byproducts and Chlorinated Solvents in Drinking Water by Liquid-Liquid
Extraction and Gas Chromatography With Electron-Capture Detection. 1990.
Table IF.
(3) National Exposure Risk Laboratory-Cincinnati, U.S. Environmental
Protection Agency, Cincinnati OH (US EPA). Available from http://
water.epa.gov/scitech/methods/cwa/index.cfm or from the National
Technical Information Service (NTIS), 5285 Port Royal Road, Springfield,
VA 22161. Telephone: 800-553-6847.
(i) Methods for the Determination of Inorganic Substances in
Environmental Samples. August 1993. EPA/600/R-93/100, Pub. No. PB
94120821. Table IB, Note 52.
(A) Method 180.1, Determination of Turbidity by Nephelometry.
Revision 2.0. Table IB, Note 52.
(B) Method 300.0, Determination of Inorganic Anions by Ion
Chromatography. Revision 2.1. Table IB, Note 52.
(C) Method 335.4, Determination of Total Cyanide by Semi-Automated
Colorimetry. Revision 1.0. Table IB, Notes 52 and 57.
(D) Method 350.1, Determination of Ammonium Nitrogen by Semi-
Automated Colorimetry. Revision 2.0. Table IB, Notes 30 and 52.
(E) Method 351.2, Determination of Total Kjeldahl Nitrogen by Semi-
Automated Colorimetry. Revision 2.0. Table IB, Note 52.
[[Page 53]]
(F) Method 353.2, Determination of Nitrate-Nitrite Automated
Colorimetry. Revision 2.0. Table IB, Note 52.
(G) Method 365.1, Determination of Phosphorus by Automated
Colorimetry. Revision 2.0. Table IB, Note 52.
(H) Method 375.2, Determination of Sulfate by Automated Colorimetry.
Revision 2.0. Table IB, Note 52.
(I) Method 410.4, Determination of Chemical Oxygen Demand by Semi-
Automated Colorimetry. Revision 2.0. Table IB, Note 52.
(ii) Methods for the Determination of Metals in Environmental
Samples, Supplement I. May 1994. EPA/600/R-94/111, Pub. No. PB 95125472.
Table IB, Note 52.
(A) Method 200.7, Determination of Metals and Trace Elements in
Water and Wastes by Inductively Coupled Plasma-Atomic Emission
Spectrometry. Revision 4.4. Table IB, Note 52.
(B) Method 200.8, Determination of Trace Elements in Water and
Wastes by Inductively Coupled Plasma Mass Spectrometry. Revision 5.3.
Table IB, Note 52.
(C) Method 200.9, Determination of Trace Elements by Stabilized
Temperature Graphite Furnace Atomic Absorption Spectrometry. Revision
2.2. Table IB, Note 52.
(D) Method 218.6, Determination of Dissolved Hexavalent Chromium in
Drinking Water, Groundwater, and Industrial Wastewater Effluents by Ion
Chromatography. Revision 3.3. Table IB, Note 52.
(E) Method 245.1, Determination of Mercury in Water by Cold Vapor
Atomic Absorption Spectrometry. Revision 3.0. Table IB, Note 52.
(4) National Exposure Risk Laboratory-Cincinnati, U.S. Environmental
Protection Agency, Cincinnati OH (US EPA). Available at http://
water.epa.gov/scitech/methods/cwa/index.cfm.
(i) EPA Method 200.5, Determination of Trace Elements in Drinking
Water by Axially Viewed Inductively Coupled Plasma-Atomic Emission
Spectrometry. Revision 4.2, October 2003. EPA/600/R-06/115. Table IB,
Note 68.
(ii) EPA Method 525.2, Determination of Organic Compounds in
Drinking Water by Liquid-Solid Extraction and Capillary Column Gas
Chromatography/Mass Spectrometry. Revision 2.0, 1995. Table ID, Note 10.
(5) Office of Research and Development, Cincinnati OH. U.S.
Environmental Protection Agency, Cincinnati OH (US EPA). Available at
http://water.epa.gov/scitech/methods/cwa/index.cfm or from ORD
Publications, CERI, U.S. Environmental Protection Agency, Cincinnati OH
45268.
(i) Methods for Benzidine, Chlorinated Organic Compounds,
Pentachlorophenol, and Pesticides in Water and Wastewater. 1978. Table
IC, Note 3; Table ID, Note 3.
(ii) Methods for Chemical Analysis of Water and Wastes. March 1979.
EPA-600/4-79-020. Table IB, Note 1.
(iii) Methods for Chemical Analysis of Water and Wastes. Revised
March 1983. EPA-600/4-79-020. Table IB, Note 1.
(A) Method 120.1, Conductance, Specific Conductance, [micro]mhos at
25 [deg]C. Revision 1982. Table IB, Note 1.
(B) Method 130.1, Hardness, Total (mg/L as CaCO3),
Colorimetric, Automated EDTA. Issued 1971. Table IB, Note 1.
(C) Method 150.2, pH, Continuous Monitoring (Electrometric).
December 1982. Table IB, Note 1.
(D) Method 160.4, Residue, Volatile, Gravimetric, Ignition at 550
[deg]C. Issued 1971. Table IB, Note 1.
(E) Method 206.5, Arsenic, Sample Digestion Prior to Total Arsenic
Analysis by Silver Diethyldithiocarbamate or Hydride Procedures. Issued
1978. Table IB, Note 1.
(F) Method 231.2, Gold, Atomic Absorption, Furnace Technique. Issued
1978. Table IB, Note 1.
(G) Method 245.2, Mercury, Automated Cold Vapor Technique. Issued
1974. Table IB, Note 1.
(H) Method 252.2, Osmium, Atomic Absorption, Furnace Technique.
Issued 1978. Table IB, Note 1.
(I) Method 253.2, Palladium, Atomic Absorption, Furnace Technique.
Issued 1978. Table IB, Note 1.
(J) Method 255.2, Platinum, Atomic Absorption, Furnace Technique.
Issued 1978. Table IB, Note 1.
(K) Method 265.2, Rhodium, Atomic Absorption, Furnace Technique.
Issued 1978. Table IB, Note 1.
[[Page 54]]
(L) Method 279.2, Thallium, Atomic Absorption, Furnace Technique.
Issued 1978. Table IB, Note 1.
(M) Method 283.2, Titanium, Atomic Absorption, Furnace Technique.
Issued 1978. Table IB, Note 1.
(N) Method 289.2, Zinc, Atomic Absorption, Furnace Technique. Issued
1978. Table IB, Note 1.
(O) Method 310.2, Alkalinity, Colorimetric, Automated, Methyl
Orange. Revision 1974. Table IB, Note 1.
(P) Method 351.1, Nitrogen, Kjeldahl, Total, Colorimetric, Automated
Phenate. Revision 1978. Table IB, Note 1.
(Q) Method 352.1, Nitrogen, Nitrate, Colorimetric, Brucine. Issued
1971. Table IB, Note 1.
(R) Method 365.3, Phosphorus, All Forms, Colorimetric, Ascorbic
Acid, Two Reagent. Issued 1978. Table IB, Note 1.
(S) Method 365.4, Phosphorus, Total, Colorimetric, Automated, Block
Digestor AA II. Issued 1974. Table IB, Note 1.
(T) Method 410.3, Chemical Oxygen Demand, Titrimetric, High Level
for Saline Waters. Revision 1978. Table IB, Note 1.
(U) Method 420.1, Phenolics, Total Recoverable, Spectrophotometric,
Manual 4-AAP With Distillation. Revision 1978. Table IB, Note 1.
(iv) Prescribed Procedures for Measurement of Radioactivity in
Drinking Water. 1980. EPA-600/4-80-032. Table IE.
(A) Method 900.0, Gross Alpha and Gross Beta Radioactivity. Table
IE.
(B) Method 903.0, Alpha-Emitting iRadio Isotopes. Table IE.
(C) Method 903.1, Radium-226, Radon Emanation Technique. Table IE.
(D) Appendix B, Error and Statistical Calculations. Table IE.
(6) Office of Science and Technology, U.S. Environmental Protection
Agency, Washington DC (US EPA). Available at http://water.epa.gov/
scitech/methods/cwa/index.cfm.
(i) Method 1625C, Semivolatile Organic Compounds by Isotope Dilution
GCMS. 1989. Table IF.
(ii) [Reserved]
(7) Office of Water, U.S. Environmental Protection Agency,
Washington DC (US EPA). Available at http://water.epa.gov/scitech/
methods/cwa/index.cfm or from National Technical Information Service,
5285 Port Royal Road, Springfield, Virginia 22161.
(i) Method 1631, Mercury in Water by Oxidation, Purge and Trap, and
Cold Vapor Atomic Fluorescence Spectrometry. Revision E, August 2002.
EPA-821-R-02-019, Pub. No. PB2002-108220. Table IB, Note 43.
(ii) Kelada-01, Kelada Automated Test Methods for Total Cyanide,
Acid Dissociable Cyanide, and Thiocyanate. Revision 1.2, August 2001.
EPA 821-B-01-009, Pub. No. PB 2001-108275. Table IB, Note 55.
(iii) In the compendium Analytical Methods for the Determination of
Pollutants in Pharmaceutical Manufacturing Industry Wastewaters. July
1998. EPA 821-B-98-016, Pub. No. PB95201679. Table IF, Note 1.
(A) EPA Method 1666, Volatile Organic Compounds Specific to the
Pharmaceutical Industry by Isotope Dilution GC/MS. Table IF, Note 1.
(B) EPA Method 1667, Formaldehyde, Isobutyraldehyde, and Furfural by
Derivatization Followed by High Performance Liquid Chromatography. Table
IF.
(C) Method 1671, Volatile Organic Compounds Specific to the
Pharmaceutical Manufacturing Industry by GC/FID. Table IF.
(iv) Methods For The Determination of Nonconventional Pesticides In
Municipal and Industrial Wastewater, Volume I. Revision I, August 1993.
EPA 821-R-93-010A, Pub. No. PB 94121654. Tables ID, IG.
(A) Method 608.1, Organochlorine Pesticides. Table ID, Note 10;
Table IG, Note 3.
(B) Method 608.2, Certain Organochlorine Pesticides. Table ID, Note
10; Table IG, Note 3.
(C) Method 614, Organophosphorus Pesticides. Table ID, Note 10;
Table IG, Note 3.
(D) Method 614.1, Organophosphorus Pesticides. Table ID, Note 10;
Table IG, Note 3.
(E) Method 615, Chlorinated Herbicides. Table ID, Note 10; Table IG,
Note 3.
(F) Method 617, Organohalide Pesticides and PCBs. Table ID, Note 10;
Table IG, Note 3.
[[Page 55]]
(G) Method 619, Triazine Pesticides. Table ID, Note 10; Table IG,
Note 3.
(H) Method 622, Organophosphorus Pesticides. Table ID, Note 10;
Table IG, Note 3.
(I) Method 622.1, Thiophosphate Pesticides. Table ID, Note 10; Table
IG, Note 3.
(J) Method 627, Dinitroaniline Pesticides. Table ID, Note 10; Table
IG, Notes 1 and 3.
(K) Method 629, Cyanazine. Table IG, Note 3.
(L) Method 630, Dithiocarbamate Pesticides. Table IG, Note 3.
(M) Method 630.1, Dithiocarbamate Pesticides. Table IG, Note 3.
(N) Method 631, Benomyl and Carbendazim. Table IG, Note 3.
(O) Method 632, Carbamate and Urea Pesticides. Table ID, Note 10;
Table IG, Note 3.
(P) Method 632.1, Carbamate and Amide Pesticides. Table IG, Note 3.
(Q) Method 633, Organonitrogen Pesticides. Table IG, Note 3.
(R) Method 633.1, Neutral Nitrogen-Containing Pesticides. Table IG,
Note 3.
(S) Method 637, MBTS and TCMTB. Table IG, Note 3.
(T) Method 644, Picloram. Table IG, Note 3.
(U) Method 645, Certain Amine Pesticides and Lethane. Table IG, Note
3.
(V) Method 1656, Organohalide Pesticides. Table ID, Note 10; Table
IG, Notes 1 and 3.
(W) Method 1657, Organophosphorus Pesticides. Table ID, Note 10;
Table IG, Note 3.
(X) Method 1658, Phenoxy-Acid Herbicides. Table IG, Note 3.
(Y) Method 1659, Dazomet. Table IG, Note 3.
(Z) Method 1660, Pyrethrins and Pyrethroids. Table IG, Note 3.
(AA) Method 1661, Bromoxynil. Table IG, Note 3.
(BB) Ind-01. Methods EV-024 and EV-025, Analytical Procedures for
Determining Total Tin and Triorganotin in Wastewater. Table IG, Note 3.
(v) Methods For The Determination of Nonconventional Pesticides In
Municipal and Industrial Wastewater, Volume II. August 1993. EPA 821-R-
93-010B, Pub. No. PB 94166311. Table IG.
(A) Method 200.9, Determination of Trace Elements by Stabilized
Temperature Graphite Furnace Atomic Absorption Spectrometry. Table IG,
Note 3.
(B) Method 505, Analysis of Organohalide Pesticides and Commercial
Polychlorinated Biphenyl (PCB) Products in Water by Microextraction and
Gas Chromatography. Table ID, Note 10; Table IG, Note 3.
(C) Method 507, The Determination of Nitrogen- and Phosphorus-
Containing Pesticides in Water by Gas Chromatography with a Nitrogen-
Phosphorus Detector. Table ID, Note 10; Table IG, Note 3.
(D) Method 508, Determination of Chlorinated Pesticides in Water by
Gas Chromatography with an Electron Capture Detector. Table ID, Note 10;
Table IG, Note 3.
(E) Method 515.1, Determination of Chlorinated Acids in Water by Gas
Chromatography with an Electron Capture Detector. Table IG, Notes 2 and
3.
(F) Method 515.2, Determination of Chlorinated Acids in Water Using
Liquid-Solid Extraction and Gas Chromatography with an Electron Capture
Detector. Table IG, Notes 2 and 3.
(G) Method 525.1, Determination of Organic Compounds in Drinking
Water by Liquids-Solid Extraction and Capillary Column Gas
Chromatography/Mass Spectrometry. Table ID, Note 10; Table IG, Note 3.
(H) Method 531.1, Measurement of N-Methylcarbamoyloximes and N-
Methylcarbamates in Water by Direct Aqueous Injection HPLC with Post-
Column Derivatization. Table ID, Note 10; Table IG, Note 3.
(I) Method 547, Determination of Glyphosate in Drinking Water by
Direct-Aqueous-Injection HPLC, Post-Column Derivatization, and
Fluorescence Detection. Table IG, Note 3.
(J) Method 548, Determination of Endothall in Drinking Water by
Aqueous Derivatization, Liquid-Solid Extraction, and Gas Chromatography
with Electron-Capture Detector. Table IG, Note 3.
(K) Method 548.1, Determination of Endothall in Drinking Water by
Ion-Exchange Extraction, Acidic Methanol Methylation and Gas
Chromatography/Mass Spectrometry. Table IG, Note 3.
[[Page 56]]
(L) Method 553, Determination of Benzidines and Nitrogen-Containing
Pesticides in Water by Liquid-Liquid Extraction or Liquid-Solid
Extraction and Reverse Phase High Performance Liquid Chromatography/
Particle Beam/Mass Spectrometry Table ID, Note 10; Table IG, Note 3.
(M) Method 555, Determination of Chlorinated Acids in Water by High
Performance Liquid Chromatography With a Photodiode Array Ultraviolet
Detector. Table IG, Note 3.
(vi) In the compendium Methods for the Determination of Organic
Compounds in Drinking Water. Revised July 1991, December 1998. EPA-600/
4-88-039, Pub. No. PB92-207703. Table IF.
(A) EPA Method 502.2, Volatile Organic Compounds in Water by Purge
and Trap Capillary Column Gas Chromatography with Photoionization and
Electrolytic Conductivity Detectors in Series. Table IF.
(B) [Reserved]
(vii) In the compendium Methods for the Determination of Organic
Compounds in Drinking Water-Supplement II. August 1992. EPA-600/R-92-
129, Pub. No. PB92-207703. Table IF.
(A) EPA Method 524.2, Measurement of Purgeable Organic Compounds in
Water by Capillary Column Gas Chromatography/Mass Spectrometry. Table
IF.
(B) [Reserved]
(viii) Methods for Measuring the Acute Toxicity of Effluents and
Receiving Waters to Freshwater and Marine Organisms, Fifth Edition.
October 2002. EPA 821-R-02-012, Pub. No. PB2002-108488. Table IA, Note
26.
(ix) Short-Term Methods for Measuring the Chronic Toxicity of
Effluents and Receiving Waters to Freshwater Organisms, Fourth Edition.
October 2002. EPA 821-R-02-013, Pub. No. PB2002-108489. Table IA, Note
27.
(x) Short-Term Methods for Measuring the Chronic Toxicity of
Effluents and Receiving Waters to Marine and Estuarine Organisms, Third
Edition. October 2002. EPA 821-R-02-014, Pub. No. PB2002-108490. Table
IA, Note 28.
(8) Office of Water, U.S. Environmental Protection Agency,
Washington DC (US EPA). Available at http://water.epa.gov/scitech/
methods/cwa/index.cfm.
(i) Method 245.7, Mercury in Water by Cold Vapor Atomic Fluorescence
Spectrometry. Revision 2.0, February 2005. EPA-821-R-05-001. Table IB,
Note 17.
(ii) Method 1103.1: Escherichia coli (E. coli) in Water by Membrane
Filtration Using membrane-Thermotolerant Escherichia coli Agar (mTEC).
March 2010. EPA-621-R-10-002. Table IH, Note 19.
(iii) Method 1106.1: Enterococci in Water by Membrane Filtration
Using membrane-Enterococcus-Esculin Iron Agar (mE-EIA). December 2009.
EPA-621-R-09-015. Table IH, Note 23.
(iv) Method 1600: Enterococci in Water by Membrane Filtration Using
membrane-Enterococcus Indoxyl-[beta]-D-Glucoside Agar (mEI). September
2014. EPA-821-R-14-011. Table IA, Note 25; Table IH, Note 24.
(v) Method 1603: Escherichia coli (E. coli) in Water by Membrane
Filtration Using Modified membrane-Thermotolerant Escherichia coli Agar
(Modified mTEC). September 2014. EPA-821-R-14-010. Table IA, Note 22;
Table IH, Note 20.
(vi) Method 1604: Total Coliforms and Escherichia coli (E. coli) in
Water by Membrane Filtration Using a Simultaneous Detection Technique
(MI Medium). September 2002. EPA-821-R-02-024. Table IH, Note 21.
(vii) Method 1622: Cryptosporidium in Water by Filtration/IMS/FA.
December 2005. EPA-821-R-05-001. Table IH, Note 25.
(viii) Method 1623: Cryptosporidium and Giardia in Water by
Filtration/IMS/FA. December 2005. EPA-821-R-05-002. Table IH, Note 26.
(ix) Method 1627, Kinetic Test Method for the Prediction of Mine
Drainage Quality. December 2011. EPA-821-R-09-002. Table IB, Note 69.
(x) Method 1664, n-Hexane Extractable Material (HEM; Oil and Grease)
and Silica Gel Treated n-Hexane Extractable Material (SGT-HEM; Non-polar
Material) by Extraction and Gravimetry. Revision A, February 1999. EPA-
821-R-98-002. Table IB, Notes 38 and 42.
(xi) Method 1664, n-Hexane Extractable Material (HEM; Oil and
Grease) and Silica Gel Treated n-Hexane Extractable Material (SGT-HEM;
Non-polar Material) by Extraction and Gravimetry. Revision B, February
2010.
[[Page 57]]
EPA-821-R-10-001. Table IB, Notes 38 and 42.
(xii) Method 1669, Sampling Ambient Water for Trace Metals at EPA
Water Quality Criteria Levels. July 1996. Table IB, Note 43.
(xiii) Method 1680: Fecal Coliforms in Sewage Sludge (Biosolids) by
Multiple-Tube Fermentation using Lauryl Tryptose Broth (LTB) and EC
Medium. September 2014. EPA-821-R-14-009. Table IA, Note 15.
(xiv) Method 1681: Fecal Coliforms in Sewage Sludge (Biosolids) by
Multiple-Tube Fermentation using A-1 Medium. July 2006. EPA 821-R-06-
013. Table IA, Note 20.
(xv) Method 1682: Salmonella in Sewage Sludge (Biosolids) by
Modified Semisolid Rappaport-Vassiliadis (MSRV) Medium. September 2014.
EPA 821-R-14-012. Table IA, Note 23.
(9) American National Standards Institute, 1430 Broadway, New York
NY 10018.
(i) ANSI. American National Standard on Photographic Processing
Effluents. April 2, 1975. Table IB, Note 9.
(ii) [Reserved]
(10) American Public Health Association, 1015 15th Street NW.,
Washington, DC 20005. Standard Methods Online is available through the
Standard Methods Web site (http://www.standardmethods.org).
(i) Standard Methods for the Examination of Water and Wastewater.
14th Edition, 1975. Table IB, Notes 17 and 27.
(ii) Standard Methods for the Examination of Water and Wastewater.
15th Edition, 1980, Table IB, Note 30; Table ID.
(iii) Selected Analytical Methods Approved and Cited by the United
States Environmental Protection Agency, Supplement to the 15th Edition
of Standard Methods for the Examination of Water and Wastewater. 1981.
Table IC, Note 6; Table ID, Note 6.
(iv) Standard Methods for the Examination of Water and Wastewater.
18th Edition, 1992. Tables IA, IB, IC, ID, IE, and IH.
(v) Standard Methods for the Examination of Water and Wastewater.
19th Edition, 1995. Tables IA, IB, IC, ID, IE, and IH.
(vi) Standard Methods for the Examination of Water and Wastewater.
20th Edition, 1998. Tables IA, IB, IC, ID, IE, and IH.
(vii) Standard Methods for the Examination of Water and Wastewater.
21st Edition, 2005. Table IB, Notes 17 and 27.
(viii) 2120, Color. 2011. Table IB.
(ix) 2130, Turbidity. 2011. Table IB.
(x) 2310, Acidity. 2011. Table IB.
(xi) 2320, Alkalinity. 2011. Table IB.
(xii) 2340, Hardness. 2011. Table IB.
(xiii) 2510, Conductivity. 2011. Table IB.
(xiv) 2540, Solids. 2011. Table IB.
(xv) 2550, Temperature. 2010. Table IB.
(xvi) 3111, Metals by Flame Atomic Absorption Spectrometry. 2011.
Table IB.
(xvii) 3112, Metals by Cold-Vapor Atomic Absorption Spectrometry.
2011. Table IB.
(xviii) 3113, Metals by Electrothermal Atomic Absorption
Spectrometry. 2010. Table IB.
(xix) 3114, Arsenic and Selenium by Hydride Generation/Atomic
Absorption Spectrometry. 2011. Table IB.
(xx) 3120, Metals by Plasma Emission Spectroscopy. 2011. Table IB.
(xxi) 3125, Metals by Inductively Coupled Plasma-Mass Spectrometry.
2011. Table IB.
(xxii) 3500-Al, Aluminum. 2011. Table IB.
(xxiii) 3500-As, Arsenic. 2011. Table IB.
(xxiv) 3500-Ca, Calcium. 2011. Table IB.
(xxv) 3500-Cr, Chromium. 2011. Table IB.
(xxvi) 3500-Cu, Copper. 2011. Table IB.
(xxvii) 3500-Fe, Iron. 2011. Table IB.
(xxviii) 3500-Pb, Lead. 2011. Table IB.
(xxix) 3500-Mn, Manganese. 2011. Table IB.
(xxx) 3500-K, Potassium. 2011. Table IB.
(xxxi) 3500-Na, Sodium. 2011. Table IB.
(xxxii) 3500-V, Vanadium. 2011. Table IB.
(xxxiii) 3500-Zn, Zinc. 2011. Table IB.
(xxxiv) 4110, Determination of Anions by Ion Chromatography. 2011.
Table IB.
(xxxv) 4140, Inorganic Anions by Capillary Ion Electrophoresis.
2011. Table IB.
[[Page 58]]
(xxxvi) 4500-B, Boron. 2011. Table IB.
(xxxvii) 4500-Cl-, Chloride. 2011. Table IB.
(xxxviii) 4500-Cl, Chlorine (Residual). 2011. Table IB.
(xxxix) 4500-CN-, Cyanide. 2011. Table IB.
(xl) 4500-F-, Fluoride. 2011. Table IB.
(xli) 4500-H\+\, pH Value. 2011. Table IB.
(xlii) 4500-NH3, Nitrogen (Ammonia). 2011. Table IB.
(xliii) 4500-NO2-, Nitrogen (Nitrite). 2011.
Table IB.
(xliv) 4500-NO3-, Nitrogen (Nitrate). 2011.
Table IB.
(xlv) 4500-Norg, Nitrogen (Organic). 2011. Table IB.
(xlvi) 4500-O, Oxygen (Dissolved). 2011. Table IB.
(xlvii) 4500-P, Phosphorus. 2011. Table IB.
(xlviii) 4500-SiO2, Silica. 2011. Table IB.
(xlix) 4500-S2-, Sulfide. 2011. Table IB.
(l) 4500-SO32-, Sulfite. 2011. Table IB.
(li) 4500-SO42-, Sulfate. 2011. Table IB.
(lii) 5210, Biochemical Oxygen Demand (BOD). 2011. Table IB.
(liii) 5220, Chemical Oxygen Demand (COD). 2011. Table IB.
(liv) 5310, Total Organic Carbon (TOC). 2011. Table IB.
(lv) 5520, Oil and Grease. 2011. Table IB.
(lvi) 5530, Phenols. 2010. Table IB.
(lvii) 5540, Surfactants. 2011. Table IB.
(lviii) 6200, Volatile Organic Compounds. 2011. Table IC.
(lix) 6410, Extractable Base/Neutrals and Acids. 2000. Tables IC,
ID.
(lx) 6420, Phenols. 2000. Table IC.
(lxi) 6440, Polynuclear Aromatic Hydrocarbons. 2005. Table IC.
(lxii) 6630, Organochlorine Pesticides. 2007. Table ID.
(lxiii) 6640, Acidic Herbicide Compounds. 2006. Table ID.
(lxiv) 7110, Gross Alpha and Gross Beta Radioactivity (Total,
Suspended, and Dissolved). 2000. Table IE.
(lxv) 7500, Radium. 2001. Table IE.
(lxvi) 9213, Recreational Waters. 2007. Table IH.
(lxvii) 9221, Multiple-Tube Fermentation Technique for Members of
the Coliform Group. 2006. Table IA, Notes 12 and 14; Table IH, Notes 11
and 13.
(lxviii) 9222, Membrane Filter Technique for Members of the Coliform
Group. 2006. Table IA; Table IH, Note 18.
(lxix) 9223, Enzyme Substrate Coliform Test. 2004. Table IA; Table
IH.
(lxx) 9230, Fecal Enterococcus/Streptococcus Groups. 2007. Table IA;
Table IH.
(11) The Analyst, The Royal Society of Chemistry, RSC Publishing,
Royal Society of Chemistry, Thomas Graham House, Science Park, Milton
Road, Cambridge CB4 0WF, United Kingdom. (Also available from most
public libraries.)
(i) Spectrophotometric Determination of Ammonia: A Study of a
Modified Berthelot Reaction Using Salicylate and Dichloroisocyanurate.
Krom, M.D. 105:305-316, April 1980. Table IB, Note 60.
(ii) [Reserved]
(12) Analytical Chemistry, ACS Publications, 1155 Sixteenth St. NW.,
Washington DC 20036. (Also available from most public libraries.)
(i) Spectrophotometric and Kinetics Investigation of the Berthelot
Reaction for the Determination of Ammonia. Patton, C.J. and S.R. Crouch.
49(3):464-469, March 1977. Table IB, Note 60.
(ii) [Reserved]
(13) AOAC International, 481 North Frederick Avenue, Suite 500,
Gaithersburg, MD 20877-2417.
(i) Official Methods of Analysis of AOAC International. 16th
Edition, 4th Revision, 1998.
(A) 920.203, Manganese in Water, Persulfate Method. Table IB, Note
3.
(B) 925.54, Sulfate in Water, Gravimetric Method. Table IB, Note 3.
(C) 973.40, Specific Conductance of Water. Table IB, Note 3.
(D) 973.41, pH of Water. Table IB, Note 3.
(E) 973.43, Alkalinity of Water, Titrimetric Method. Table IB, Note
3.
(F) 973.44, Biochemical Oxygen Demand (BOD) of Water, Incubation
Method. Table IB, Note 3.
(G) 973.45, Oxygen (Dissolved) in Water, Titrimetric Methods. Table
IB, Note 3.
(H) 973.46, Chemical Oxygen Demand (COD) of Water, Titrimetric
Methods. Table IB, Note 3.
[[Page 59]]
(I) 973.47, Organic Carbon in Water, Infrared Analyzer Method. Table
IB, Note 3.
(J) 973.48, Nitrogen (Total) in Water, Kjeldahl Method. Table IB,
Note 3.
(K) 973.49, Nitrogen (Ammonia) in Water, Colorimetric Method. Table
IB, Note 3.
(L) 973.50, Nitrogen (Nitrate) in Water, Brucine Colorimetric
Method. Table IB, Note 3.
(M) 973.51, Chloride in Water, Mercuric Nitrate Method. Table IB,
Note 3.
(N) 973.52, Hardness of Water. Table IB, Note 3.
(O) 973.53, Potassium in Water, Atomic Absorption Spectrophotometric
Method. Table IB, Note 3.
(P) 973.54, Sodium in Water, Atomic Absorption Spectrophotometric
Method. Table IB, Note 3.
(Q) 973.55, Phosphorus in Water, Photometric Method. Table IB, Note
3.
(R) 973.56, Phosphorus in Water, Automated Method. Table IB, Note 3.
(S) 974.27, Cadmium, Chromium, Copper, Iron, Lead, Magnesium,
Manganese, Silver, Zinc in Water, Atomic Absorption Spectrophotometric
Method. Table IB, Note 3.
(T) 977.22, Mercury in Water, Flameless Atomic Absorption
Spectrophotometric Method. Table IB, Note 3.
(U) 991.15. Total Coliforms and Escherichia coli in Water Defined
Substrate Technology (Colilert) Method. Table IA, Note 10; Table IH,
Note 10.
(V) 993.14, Trace Elements in Waters and Wastewaters, Inductively
Coupled Plasma-Mass Spectrometric Method. Table IB, Note 3.
(W) 993.23, Dissolved Hexavalent Chromium in Drinking Water, Ground
Water, and Industrial Wastewater Effluents, Ion Chromatographic Method.
Table IB, Note 3.
(X) 993.30, Inorganic Anions in Water, Ion Chromatographic Method.
Table IB, Note 3.
(ii) [Reserved]
(14) Applied and Environmental Microbiology, American Society for
Microbiology, 1752 N Street NW., Washington DC 20036. (Also available
from most public libraries.)
(i) New Medium for the Simultaneous Detection of Total Coliforms and
Escherichia coli in Water. Brenner, K.P., C.C. Rankin, Y.R. Roybal, G.N.
Stelma, Jr., P.V. Scarpino, and A.P. Dufour. 59:3534-3544, November
1993. Table IH, Note 21.
(ii) [Reserved]
(15) ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West
Conshohocken, PA 19428-2959, or online at http://www.astm.org.
(i) Annual Book of ASTM Standards, Water, and Environmental
Technology, Section 11, Volumes 11.01 and 11.02. 1994. Tables IA, IB,
IC, ID, IE, and IH.
(ii) Annual Book of ASTM Standards, Water, and Environmental
Technology, Section 11, Volumes 11.01 and 11.02. 1996. Tables IA, IB,
IC, ID, IE, and IH.
(iii) Annual Book of ASTM Standards, Water, and Environmental
Technology, Section 11, Volumes 11.01 and 11.02. 1999. Tables IA, IB,
IC, ID, IE, and IH.
(iv) Annual Book of ASTM Standards, Water, and Environmental
Technology, Section 11, Volumes 11.01 and 11.02. 2000. Tables IA, IB,
IC, ID, IE, and IH.
(v) ASTM D511-09, Standard Test Methods for Calcium and Magnesium in
Water. May 2009. Table IB.
(vi) ASTM D512-04, Standard Test Methods for Chloride Ion in Water.
July 2004. Table IB.
(vii) ASTM D515-88, Test Methods for Phosphorus in Water, March
1989. Table IB.
(viii) ASTM D516-11, Standard Test Method for Sulfate Ion in Water,
September 2011. Table IB.
(ix) ASTM D858-12, Standard Test Methods for Manganese in Water.
September 2012. Table IB.
(x) ASTM D859-10, Standard Test Method for Silica in Water. July
2010. Table IB.
(xi) ASTM D888-09, Standard Test Methods for Dissolved Oxygen in
Water. December 2009. Table IB.
(xii) ASTM D1067-11, Standard Test Methods for Acidity or Alkalinity
of Water. April 2011. Table IB.
(xiii) ASTM D1068-10, Standard Test Methods for Iron in Water.
October 2010. Table IB.
(xiv) ASTM D1125-95 (Reapproved 1999), Standard Test Methods for
Electrical Conductivity and Resistivity of Water. December 1995. Table
IB.
[[Page 60]]
(xv) ASTM D1126-12, Standard Test Method for Hardness in Water.
March 2012. Table IB.
(xvi) ASTM D1179-10, Standard Test Methods for Fluoride Ion in
Water. July 2010. Table IB.
(xvii) ASTM D1246-10, Standard Test Method for Bromide Ion in Water.
July 2010. Table IB.
(xviii) ASTM D1252-06, Standard Test Methods for Chemical Oxygen
Demand (Dichromate Oxygen Demand) of Water. February 2006. Table IB.
(xix) ASTM D1253-08, Standard Test Method for Residual Chlorine in
Water. October 2008. Table IB.
(xx) ASTM D1293-99, Standard Test Methods for pH of Water. March
2000. Table IB.
(xxi) ASTM D1426-08, Standard Test Methods for Ammonia Nitrogen in
Water. September 2008. Table IB.
(xxii) ASTM D1687-12 (Approved September 1, 2012), Standard Test
Methods for Chromium in Water. August 2007. Table IB.
(xxiii) ASTM D1688-12, Standard Test Methods for Copper in Water.
September 2012. Table IB.
(xxiv) ASTM D1691-12, Standard Test Methods for Zinc in Water.
September 2012. Table IB.
(xxv) ASTM D1783-01 (Reapproved 2007), Standard Test Methods for
Phenolic Compounds in Water. January 2008). Table IB.
(xxvi) ASTM D1886-08, Standard Test Methods for Nickel in Water.
October 2008. Table IB.
(xxvii) ASTM D1889-00, Standard Test Method for Turbidity of Water.
October 2000. Table IB.
(xxviii) ASTM D1890-96, Standard Test Method for Beta Particle
Radioactivity of Water. April 1996. Table IE.
(xxix) ASTM D1943-96, Standard Test Method for Alpha Particle
Radioactivity of Water. April 1996. Table IE.
(xxx) ASTM D1976-12, Standard Test Method for Elements in Water by
Inductively-Coupled Argon Plasma Atomic Emission Spectroscopy. March
2012. Table IB.
(xxxi) ASTM D2036-09, Standard Test Methods for Cyanides in Water.
October 2009. Table IB.
(xxxii) ASTM D2330-02, Standard Test Method for Methylene Blue
Active Substances. August 2002. Table IB.
(xxxiii) ASTM D2460-97, Standard Test Method for Alpha-Particle-
Emitting Isotopes of Radium in Water. October 1997. Table IE.
(xxxiv) ASTM D2972-08, Standard Tests Method for Arsenic in Water.
October 2008. Table IB.
(xxxv) ASTM D3223-12, Standard Test Method for Total Mercury in
Water. September 2012. Table IB.
(xxxvi) ASTM D3371-95, Standard Test Method for Nitriles in Aqueous
Solution by Gas-Liquid Chromatography, February 1996. Table IF.
(xxxvii) ASTM D3373-12, Standard Test Method for Vanadium in Water.
September 2012. Table IB.
(xxxviii) ASTM D3454-97, Standard Test Method for Radium-226 in
Water. February 1998. Table IE.
(xxxix) ASTM D3557-12, Standard Test Method for Cadmium in Water.
September 2012. Table IB.
(xl) ASTM D3558-08, Standard Test Method for Cobalt in Water.
November 2008. Table IB.
(xli) ASTM D3559-08, Standard Test Methods for Lead in Water.
October 2008. Table IB.
(xlii) ASTM D3590-11, Standard Test Methods for Total Kjeldahl
Nitrogen in Water. April 2011. Table IB.
(xliii) ASTM D3645-08, Standard Test Methods for Beryllium in Water.
October 2008. Table IB.
(xliv) ASTM D3695-95, Standard Test Method for Volatile Alcohols in
Water by Direct Aqueous-Injection Gas Chromatography. April 1995. Table
IF.
(xlv) ASTM D3859-08, Standard Test Methods for Selenium in Water.
October 2008. Table IB.
(xlvi) ASTM D3867-04, Standard Test Method for Nitrite-Nitrate in
Water. July 2004. Table IB.
(xlvii) ASTM D4190-08, Standard Test Method for Elements in Water by
Direct-Current Plasma Atomic Emission Spectroscopy. October 2008. Table
IB.
(xlviii) ASTM D4282-02, Standard Test Method for Determination of
Free Cyanide in Water and Wastewater by Microdiffusion. August 2002.
Table IB.
(xlix) ASTM D4327-03, Standard Test Method for Anions in Water by
Chemically Suppressed Ion Chromatography. January 2003. Table IB.
(l) ASTM D4382-12, Standard Test Method for Barium in Water, Atomic
[[Page 61]]
Absorption Spectrophotometry, Graphite Furnace. September 2012. Table
IB.
(li) ASTM D4657-92 (Reapproved 1998), Standard Test Method for
Polynuclear Aromatic Hydrocarbons in Water. January 1993. Table IC.
(lii) ASTM D4658-09, Standard Test Method for Sulfide Ion in Water.
May 2009. Table IB.
(liii) ASTM D4763-88 (Reapproved 2001), Standard Practice for
Identification of Chemicals in Water by Fluorescence Spectroscopy.
September 1988. Table IF.
(liv) ASTM D4839-03, Standard Test Method for Total Carbon and
Organic Carbon in Water by Ultraviolet, or Persulfate Oxidation, or
Both, and Infrared Detection. January 2003. Table IB.
(lv) ASTM D5257-11, Standard Test Method for Dissolved Hexavalent
Chromium in Water by Ion Chromatography. April 2011. Table IB.
(lvi) ASTM D5259-92, Standard Test Method for Isolation and
Enumeration of Enterococci from Water by the Membrane Filter Procedure.
October 1992. Table IH, Note 9.
(lvii) ASTM D5392-93, Standard Test Method for Isolation and
Enumeration of Escherichia coli in Water by the Two-Step Membrane Filter
Procedure. September 1993. Table IH, Note 9.
(lviii) ASTM D5673-10, Standard Test Method for Elements in Water by
Inductively Coupled Plasma--Mass Spectrometry. September 2010. Table IB.
(lix) ASTM D5(19)907-13, Standard Test Method for Filterable Matter
(Total Dissolved Solids) and Nonfilterable Matter (Total Suspended
Solids) in Water. July 2013. Table IB.
(lx) ASTM D6503-99, Standard Test Method for Enterococci in Water
Using Enterolert. April 2000. Table IA Note 9, Table IH, Note 9.
(lxi) ASTM. D6508-10, Standard Test Method for Determination of
Dissolved Inorganic Anions in Aqueous Matrices Using Capillary Ion
Electrophoresis and Chromate Electrolyte. October 2010. Table IB, Note
54.
(lxii) ASTM. D6888-09, Standard Test Method for Available Cyanide
with Ligand Displacement and Flow Injection Analysis (FIA) Utilizing Gas
Diffusion Separation and Amperometric Detection. October 2009. Table IB,
Note 59.
(lxiii) ASTM. D6919-09, Standard Test Method for Determination of
Dissolved Alkali and Alkaline Earth Cations and Ammonium in Water and
Wastewater by Ion Chromatography. May 2009. Table IB.
(lxiv) ASTM. D7065-11, Standard Test Method for Determination of
Nonylphenol, Bisphenol A, p-tert-Octylphenol, Nonylphenol Monoethoxylate
and Nonylphenol Diethoxylate in Environmental Waters by Gas
Chromatography Mass Spectrometry. July 2011. Table IB.
(lxv) ASTM. D7237-10, Standard Test Method for Free Cyanide with
Flow Injection Analysis (FIA) Utilizing Gas Diffusion Separation and
Amperometric Detection. June 2010. Table IB.
(lxvi) ASTM. D7284-13, Standard Test Method for Total Cyanide in
Water by Micro Distillation followed by Flow Injection Analysis with Gas
Diffusion Separation and Amperometric Detection. July 2013. Table IB.
(lxvii) ASTM. D7365-09a, Standard Practice for Sampling,
Preservation, and Mitigating Interferences in Water Samples for Analysis
of Cyanide. October 2009. Table II, Notes 5 and 6.
(lxviii) ASTM. D7511-12, Standard Test Method for Total Cyanide by
Segmented Flow Injection Analysis, In-Line Ultraviolet Digestion and
Amperometric Detection. January 2012. Table IB.
(lxix) ASTM. D7573-09, Standard Test Method for Total Carbon and
Organic Carbon in Water by High Temperature Catalytic Combustion and
Infrared Detection. November 2009. Table IB.
(16) Bran & Luebbe Analyzing Technologies, Inc., Elmsford NY 10523.
(i) Industrial Method Number 378-75WA, Hydrogen Ion (pH) Automated
Electrode Method, Bran & Luebbe (Technicon) Auto Analyzer II. October
1976. Table IB, Note 21.
(ii) [Reserved]
(17) CEM Corporation, P.O. Box 200, Matthews NC 28106-0200.
(i) Closed Vessel Microwave Digestion of Wastewater Samples for
Determination of Metals. April 16, 1992. Table IB, Note 36.
(ii) [Reserved]
(18) Craig R. Chinchilla, 900 Jorie Blvd., Suite 35, Oak Brook IL
60523. Telephone: 630-645-0600.
[[Page 62]]
(i) Nitrate by Discrete Analysis Easy (1-Reagent) Nitrate Method,
(Colorimetric, Automated, 1 Reagent). Revision 1, November 12, 2011.
Table IB, Note 62.
(ii) [Reserved]
(19) Hach Company, P.O. Box 389, Loveland CO 80537.
(i) Method 8000, Chemical Oxygen Demand. Hach Handbook of Water
Analysis. 1979. Table IB, Note 14.
(ii) Method 8008, 1,10-Phenanthroline Method using FerroVer Iron
Reagent for Water. 1980. Table IB, Note 22.
(iii) Method 8009, Zincon Method for Zinc. Hach Handbook for Water
Analysis. 1979. Table IB, Note 33.
(iv) Method 8034, Periodate Oxidation Method for Manganese. Hach
Handbook for Water Analysis. 1979. Table IB, Note 23.
(v) Method 8506, Bicinchoninate Method for Copper. Hach Handbook of
Water Analysis. 1979. Table IB, Note 19.
(vi) Method 8507, Nitrogen, Nitrite--Low Range, Diazotization Method
for Water and Wastewater. 1979. Table IB, Note 25.
(vii) Method 10206, Hach Company TNTplus 835/836 Nitrate Method
10206, Spectrophotometric Measurement of Nitrate in Water and
Wastewater. Revision 2.1, January 10, 2013. Table IB, Note 75.
(viii) Method 10242, Hach Company TNTplus 880 Total Kjeldahl
Nitrogen Method 10242, Simplified Spectrophotometric Measurement of
Total Kjeldahl Nitrogen in Water and Wastewater. Revision 1.1, January
10, 2013. Table IB, Note 76.
(ix) Hach Method 10360, Luminescence Measurement of Dissolved Oxygen
in Water and Wastewater and for Use in the Determination of
BOD5 and cBOD5. Revision 1.2, October 2011. Table
IB, Note 63.
(x) m-ColiBlue24[supreg] Method, for total Coliforms and E. coli.
Revision 2, 1999. Table IA, Note 18; Table IH, Note 17.
(20) IDEXX Laboratories Inc., One Idexx Drive, Westbrook ME 04092.
(i) Colilert. 2013. Table IA, Notes 17 and 18; Table IH, Notes 14,
15 and 16.
(ii) Colilert-18. 2013. Table IA, Notes 17 and 18; Table IH, Notes
14, 15 and 16.
(iii) Enterolert. 2013. Table IA, Note 24; Table IH, Note 12.
(iv) Quanti-Tray Insert and Most Probable Number (MPN) Table. 2013.
Table IA, Note 18; Table IH, Notes 14 and 16.
(21) In-Situ Incorporated, 221 E. Lincoln Ave., Ft. Collins CO
80524. Telephone: 970-498-1500.
(i) In-Situ Inc. Method 1002-8-2009, Dissolved Oxygen Measurement by
Optical Probe. 2009. Table IB, Note 64.
(ii) In-Situ Inc. Method 1003-8-2009, Biochemical Oxygen Demand
(BOD) Measurement by Optical Probe. 2009. Table IB, Note 10.
(iii) In-Situ Inc. Method 1004-8-2009, Carbonaceous Biochemical
Oxygen Demand (CBOD) Measurement by Optical Probe. 2009. Table IB, Note
35.
(22) Journal of Chromatography, Elsevier/North-Holland, Inc.,
Journal Information Centre, 52 Vanderbilt Avenue, New York NY 10164.
(Also available from most public libraries.
(i) Direct Determination of Elemental Phosphorus by Gas-Liquid
Chromatography. Addison, R.F. and R.G. Ackman. 47(3): 421-426, 1970.
Table IB, Note 28.
(ii) [Reserved]
(23) Lachat Instruments, 6645 W. Mill Road, Milwaukee WI 53218,
Telephone: 414-358-4200.
(i) QuikChem Method 10-204-00-1-X, Digestion and Distillation of
Total Cyanide in Drinking and Wastewaters using MICRO DIST and
Determination of Cyanide by Flow Injection Analysis. Revision 2.2, March
2005. Table IB, Note 56.
(ii) [Reserved]
(24) Leck Mitchell, Ph.D., P.E., 656 Independence Valley Dr., Grand
Junction CO 81507. Telephone: 970-244-8661.
(i) Mitchell Method M5271, Determination of Turbidity by
Nephelometry. Revision 1.0, July 31, 2008. Table IB, Note 66.
(ii) Mitchell Method M5331, Determination of Turbidity by
Nephelometry. Revision 1.0, July 31, 2008. Table IB, Note 65.
(25) National Council of the Paper Industry for Air and Stream
Improvements, Inc. (NCASI), 260 Madison Avenue, New York NY 10016.
(i) NCASI Method TNTP-W10900, Total Nitrogen and Total Phophorus in
Pulp and Paper Biologically Treated
[[Page 63]]
Effluent by Alkaline Persulfate Digestion. June 2011. Table IB, Note 77.
(ii) NCASI Technical Bulletin No. 253, An Investigation of Improved
Procedures for Measurement of Mill Effluent and Receiving Water Color.
December 1971. Table IB, Note 18.
(iii) NCASI Technical Bulletin No. 803, An Update of Procedures for
the Measurement of Color in Pulp Mill Wastewaters. May 2000. Table IB,
Note 18.
(26) The Nitrate Elimination Co., Inc. (NECi), 334 Hecla St., Lake
Linden NI 49945.
(i) NECi Method N07-0003, Method for Nitrate Reductase Nitrate-
Nitrogen Analysis. Revision 9.0. March 2014. Table IB, Note 73.
(ii) [Reserved]
(27) Oceanography International Corporation, 512 West Loop, P.O. Box
2980, College Station TX 77840.
(i) OIC Chemical Oxygen Demand Method. 1978. Table IB, Note 13.
(ii) [Reserved]
(28) OI Analytical, Box 9010, College Station TX 77820-9010.
(i) Method OIA-1677-09, Available Cyanide by Ligand Exchange and
Flow Injection Analysis (FIA). Copyright 2010. Table IB, Note 59.
(ii) Method PAI-DK01, Nitrogen, Total Kjeldahl, Block Digestion,
Steam Distillation, Titrimetric Detection. Revised December 22, 1994.
Table IB, Note 39.
(iii) Method PAI-DK02, Nitrogen, Total Kjeldahl, Block Digestion,
Steam Distillation, Colorimetric Detection. Revised December 22, 1994.
Table IB, Note 40.
(iv) Method PAI-DK03, Nitrogen, Total Kjeldahl, Block Digestion,
Automated FIA Gas Diffusion. Revised December 22, 1994. Table IB, Note
41.
(29) ORION Research Corporation, 840 Memorial Drive, Cambridge,
Massachusetts 02138.
(i) ORION Research Instruction Manual, Residual Chlorine Electrode
Model 97-70. 1977. Table IB, Note 16.
(ii) [Reserved]
(30) Technicon Industrial Systems, Tarrytown NY 10591.
(i) Industrial Method Number 379-75WE Ammonia, Automated Electrode
Method, Technicon Auto Analyzer II. February 19, 1976. Table IB, Note 7.
(ii) [Reserved]
(31) Thermo Jarrell Ash Corporation, 27 Forge Parkway, Franklin MA
02038.
(i) Method AES0029. Direct Current Plasma (DCP) Optical Emission
Spectrometric Method for Trace Elemental Analysis of Water and Wastes.
1986, Revised 1991. Table IB, Note 34.
(ii) [Reserved]
(32) Thermo Scientific, 166 Cummings Center, Beverly MA 01915.
Telephone: 1-800-225-1480. www.thermoscientific.com.
(i) Thermo Scientific Orion Method AQ4500, Determination of
Turbidity by Nephelometry. Revision 5, March 12, 2009. Table IB, Note
67.
(ii) [Reserved]
(33) 3M Corporation, 3M Center Building 220-9E-10, St. Paul MN
55144-1000.
(i) Organochlorine Pesticides and PCBs in Wastewater Using Empore
\TM\ Disk'' Test Method 3M 0222. Revised October 28, 1994. Table IC,
Note 8; Table ID, Note 8.
(ii) [Reserved]
(34) Timberline Instruments, LLC, 1880 South Flatiron Ct., Unit I,
Boulder CO 80301.
(i) Timberline Amonia-001, Determination of Inorganic Ammonia by
Continuous Flow Gas Diffusion and Conductivity Cell Analysis. June 24,
2011. Table IB, Note 74.
(ii) [Reserved]
(35) U.S. Geological Survey (USGS), U.S. Department of the Interior,
Reston, Virginia. Available from USGS Books and Open-File Reports (OFR)
Section, Federal Center, Box 25425, Denver, CO 80225.
(i) Colorimetric determination of nitrate plus nitrite in water by
enzymatic reduction, automated discrete analyzer methods. U.S.
Geological Survey Techniques and Methods, Book 5--Laboratory Analysis,
Section B--Methods of the National Water Quality Laboratory, Chapter 8.
2011. Table IB, Note 72.
(ii) Methods for Determination of Inorganic Substances in Water and
Fluvial Sediments, editors, Techniques of Water-Resources Investigations
of the U.S. Geological Survey, Book 5, Chapter A1. 1979. Table IB, Note
8.
(iii) Methods for Determination of Inorganic Substances in Water and
Fluvial Sediments, Techniques of Water-Resources Investigations of the
U.S.
[[Page 64]]
Geological Survey, Book 5, Chapter A1. 1989. Table IB, Note 2.
(iv) Methods for the Determination of Organic Substances in Water
and Fluvial Sediments. Techniques of Water-Resources Investigations of
the U.S. Geological Survey, Book 5, Chapter A3. 1987. Table IB, Note 24;
Table ID, Note 4.
(v) OFR 76-177, Selected Methods of the U.S. Geological Survey of
Analysis of Wastewaters. 1976. Table IE, Note 2.
(vi) OFR 91-519, Methods of Analysis by the U.S. Geological Survey
National Water Quality Laboratory--Determination of Organonitrogen
Herbicides in Water by Solid-Phase Extraction and Capillary-Column Gas
Chromatography/Mass Spectrometry With Selected-Ion Monitoring. 1992.
Table ID, Note 14.
(vii) OFR 92-146, Methods of Analysis by the U.S. Geological Survey
National Water Quality Laboratory--Determination of Total Phosphorus by
a Kjeldahl Digestion Method and an Automated Colorimetric Finish That
Includes Dialysis. 1992. Table IB, Note 48.
(viii) OFR 93-125, Methods of Analysis by the U.S. Geological Survey
National Water Quality Laboratory--Determination of Inorganic and
Organic Constituents in Water and Fluvial Sediments. 1993. Table IB,
Note 51; Table IC, Note 9.
(ix) OFR 93-449, Methods of Analysis by the U.S. Geological Survey
National Water Quality Laboratory--Determination of Chromium in Water by
Graphite Furnace Atomic Absorption Spectrophotometry. 1993. Table IB,
Note 46.
(x) OFR 94-37, Methods of Analysis by the U.S. Geological Survey
National Water Quality Laboratory--Determination of Triazine and Other
Nitrogen-containing Compounds by Gas Chromatography With Nitrogen
Phosphorus Detectors. 1994. Table ID, Note 9.
(xi) OFR 95-181, Methods of Analysis by the U.S. Geological Survey
National Water Quality Laboratory--Determination of Pesticides in Water
by C-18 Solid-Phase Extraction and Capillary-Column Gas Chromatography/
Mass Spectrometry With Selected-Ion Monitoring. 1995. Table ID, Note 11.
(xii) OFR 97-198, Methods of Analysis by the U.S. Geological Survey
National Water Quality Laboratory--Determination of Molybdenum in Water
by Graphite Furnace Atomic Absorption Spectrophotometry. 1997. Table IB,
Note 47.
(xiii) OFR 98-165, Methods of Analysis by the U.S. Geological Survey
National Water Quality Laboratory--Determination of Elements in Whole-
Water Digests Using Inductively Coupled Plasma-Optical Emission
Spectrometry and Inductively Coupled Plasma-Mass Spectrometry. 1998.
Table IB, Note 50.
(xiv) OFR 98-639, Methods of Analysis by the U.S. Geological Survey
National Water Quality Laboratory--Determination of Arsenic and Selenium
in Water and Sediment by Graphite Furnace--Atomic Absorption
Spectrometry. 1999. Table IB, Note 49.
(xv) OFR 00-170, Methods of Analysis by the U.S. Geological Survey
National Water Quality Laboratory--Determination of Ammonium Plus
Organic Nitrogen by a Kjeldahl Digestion Method and an Automated
Photometric Finish that Includes Digest Cleanup by Gas Diffusion. 2000.
Table IB, Note 45.
(xvi) Techniques and Methods Book 5-B1, Determination of Elements in
Natural-Water, Biota, Sediment and Soil Samples Using Collision/Reaction
Cell Inductively Coupled Plasma-Mass Spectrometry. Chapter 1, Section B,
Methods of the National Water Quality Laboratory, Book 5, Laboratory
Analysis. 2006. Table IB, Note 70.
(xvii) U.S. Geological Survey Techniques of Water-Resources
Investigations, Book 5, Laboratory Analysis, Chapter A4, Methods for
Collection and Analysis of Aquatic Biological and Microbiological
Samples. 1989. Table IA, Note 4; Table IH, Note 4.
(xviii) Water-Resources Investigation Report 01-4098, Methods of
Analysis by the U.S. Geological Survey National Water Quality
Laboratory--Determination of Moderate-Use Pesticides and Selected
Degradates in Water by C-18 Solid-Phase Extraction and Gas
Chromatography/Mass Spectrometry. 2001. Table ID, Note 13.
(xix) Water-Resources Investigations Report 01-4132, Methods of
Analysis by the U.S. Geological Survey National Water Quality
Laboratory--Determination of Organic Plus Inorganic Mercury
[[Page 65]]
in Filtered and Unfiltered Natural Water With Cold Vapor-Atomic
Fluorescence Spectrometry. 2001. Table IB, Note 71.
(xx) Water-Resources Investigation Report 01-4134, Methods of
Analysis by the U.S. Geological Survey National Water Quality
Laboratory--Determination of Pesticides in Water by Graphitized Carbon-
Based Solid-Phase Extraction and High-Performance Liquid Chormatography/
Mass Spectrometry. 2001. Table ID, Note 12.
(xxi) Water Temperature--Influential Factors, Field Measurement and
Data Presentation, Techniques of Water-Resources Investigations of the
U.S. Geological Survey, Book 1, Chapter D1. 1975. Table IB, Note 32.
(36) Waters Corporation, 34 Maple Street, Milford MA 01757,
Telephone: 508-482-2131, Fax: 508-482-3625.
(i) Method D6508, Test Method for Determination of Dissolved
Inorganic Anions in Aqueous Matrices Using Capillary Ion Electrophoresis
and Chromate Electrolyte. Revision 2, December 2000. Table IB, Note 54.
(ii) [Reserved]
(c) Under certain circumstances, the Director may establish
limitations on the discharge of a parameter for which there is no test
procedure in this part or in 40 CFR parts 405 through 499. In these
instances the test procedure shall be specified by the Director.
(d) Under certain circumstances, the Administrator may approve
additional alternate test procedures for nationwide use, upon
recommendation by the Alternate Test Procedure Program Coordinator,
Washington, DC.
(e) Sample preservation procedures, container materials, and maximum
allowable holding times for parameters are cited in Tables IA, IB, IC,
ID, IE, IF, IG, and IH are prescribed in Table II. Information in the
table takes precedence over information in specific methods or
elsewhere. Any person may apply for a change from the prescribed
preservation techniques, container materials, and maximum holding times
applicable to samples taken from a specific discharge. Applications for
such limited use changes may be made by letters to the Regional
Alternative Test Procedure (ATP) Program Coordinator or the permitting
authority in the Region in which the discharge will occur. Sufficient
data should be provided to assure such changes in sample preservation,
containers or holding times do not adversely affect the integrity of the
sample. The Regional ATP Coordinator or permitting authority will review
the application and then notify the applicant and the appropriate State
agency of approval or rejection of the use of the alternate test
procedure. A decision to approve or deny any request on deviations from
the prescribed Table II requirements will be made within 90 days of
receipt of the application by the Regional Administrator. An analyst may
not modify any sample preservation and/or holding time requirements of
an approved method unless the requirements of this section are met.
Table II--Required Containers, Preservation Techniques, and Holding Times
----------------------------------------------------------------------------------------------------------------
Maximum holding time
Parameter number/name Container \1\ Preservation \2\ \3\ \4\
----------------------------------------------------------------------------------------------------------------
Table IA--Bacterial Tests
----------------------------------------------------------------------------------------------------------------
1-5. Coliform, total, fecal, and E. PA, G.................. Cool, <10 [deg]C, 8 hours.\22\ \23\
coli. 0.008% Na2S2O3 \5\.
6. Fecal streptococci................ PA, G.................. Cool, <10 [deg]C, 8 hours.\22\
0.008% Na2S2O3 \5\.
7. Enterococci....................... PA, G.................. Cool, <10 [deg]C, 8 hours.\22\
0.008% Na2S2O3 \5\.
8. Salmonella........................ PA, G.................. Cool, <10 [deg]C, 8 hours.\22\
0.008% Na2S2O3 \5\.
----------------------------------------------------------------------------------------------------------------
Table IA--Aquatic Toxicity Tests
----------------------------------------------------------------------------------------------------------------
9-12. Toxicity, acute and chronic.... P, FP, G............... Cool, <=6 [deg]C \16\.. 36 hours.
----------------------------------------------------------------------------------------------------------------
Table IB--Inorganic Tests
----------------------------------------------------------------------------------------------------------------
1. Acidity........................... P, FP, G............... Cool, <=6 [deg]C \18\.. 14 days.
2. Alkalinity........................ P, FP, G............... Cool, <=6 [deg]C \18\.. 14 days.
[[Page 66]]
4. Ammonia........................... P, FP, G............... Cool, <=6 [deg]C,\18\ 28 days.
H2SO4 to pH <2.
9. Biochemical oxygen demand......... P, FP, G............... Cool, <=6 [deg]C \18\.. 48 hours.
10. Boron............................ P, FP, or Quartz....... HNO3 to pH <2.......... 6 months.
11. Bromide.......................... P, FP, G............... None required.......... 28 days.
14. Biochemical oxygen demand, P, FP G................ Cool, <=6 [deg]C \18\.. 48 hours.
carbonaceous.
15. Chemical oxygen demand........... P, FP, G............... Cool, <=6 [deg]C,\18\ 28 days.
H2SO4 to pH <2.
16. Chloride......................... P, FP, G............... None required.......... 28 days.
17. Chlorine, total residual......... P, G................... None required.......... Analyze within 15
minutes.
21. Color............................ P, FP, G............... Cool, <=6 [deg]C \18\.. 48 hours.
23-24. Cyanide, total or available P, FP, G............... Cool, <=6 [deg]C,\18\ 14 days.
(or CATC) and free. NaOH to pH 10,5 6 reducing
agent if oxidizer
present.
25. Fluoride......................... P...................... None required.......... 28 days.
27. Hardness......................... P, FP, G............... HNO3 or H2SO4 to pH <2. 6 months.
28. Hydrogen ion (pH)................ P, FP, G............... None required.......... Analyze within 15
minutes.
31, 43. Kjeldahl and organic N....... P, FP, G............... Cool, <=6 [deg]C,\18\ 28 days.
H2SO4 to pH <2.
----------------------------------------------------------------------------------------------------------------
Table IB--Metals \7\
----------------------------------------------------------------------------------------------------------------
18. Chromium VI...................... P, FP, G............... Cool, <=6 [deg]C,\18\ 28 days.
pH = 9.3-9.7 \20\.
35. Mercury (CVAA)................... P, FP, G............... HNO3 to pH <2.......... 28 days.
35. Mercury (CVAFS).................. FP, G; and FP-lined cap 5 mL/L 12N HCl or 5 mL/ 90 days.\17\
\17\. L BrCl \17\.
3, 5-8, 12, 13, 19, 20, 22, 26, 29, P, FP, G............... HNO3 to pH <2, or at 6 months.
30, 32-34, 36, 37, 45, 47, 51, 52, least 24 hours prior
58-60, 62, 63, 70-72, 74, 75. to analysis \19\.
Metals, except boron, chromium VI,
and mercury.
38. Nitrate.......................... P, FP, G............... Cool, <=6 [deg]C \18\.. 48 hours.
39. Nitrate-nitrite.................. P, FP, G............... Cool, <=6 28 days.
[deg]C,\18\H2SO4 to pH
<2.
40. Nitrite.......................... P, FP, G............... Cool, <=6 [deg]C \18\.. 48 hours.
41. Oil and grease................... G...................... Cool to <=6 [deg]C,\18\ 28 days.
HCl or H2SO4 to pH <2.
42. Organic Carbon................... P, FP, G............... Cool to <=6 [deg]C,\18\ 28 days.
HCl, H2SO4, or H3PO4
to pH <2.
44. Orthophosphate................... P, FP, G............... Cool, to <=6 [deg]C 18 Filter within 15
24. minutes; Analyze
within 48 hours.
46. Oxygen, Dissolved Probe.......... G, Bottle and top...... None required.......... Analyze within 15
minutes.
47. Winkler.......................... G, Bottle and top...... Fix on site and store 8 hours.
in dark.
48. Phenols.......................... G...................... Cool, <=6 [deg]C,\18\ 28 days.
H2SO4 to pH <2.
49. Phosphorous (elemental).......... G...................... Cool, <=6 [deg]C \18\.. 48 hours.
50. Phosphorous, total............... P, FP, G............... Cool, <=6 [deg]C,\18\ 28 days.
H2SO4 to pH <2.
53. Residue, total................... P, FP, G............... Cool, <=6 [deg]C \18\.. 7 days.
54. Residue, Filterable.............. P, FP, G............... Cool, <=6 [deg]C \18\.. 7 days.
55. Residue, Nonfilterable (TSS)..... P, FP, G............... Cool, <=6 [deg]C \18\.. 7 days.
56. Residue, Settleable.............. P, FP, G............... Cool, <=6 [deg]C \18\.. 48 hours.
57. Residue, Volatile................ P, FP, G............... Cool, <=6 [deg]C \18\.. 7 days.
61. Silica........................... P or Quartz............ Cool, <=6 [deg]C \18\.. 28 days.
64. Specific conductance............. P, FP, G............... Cool, <=6 [deg]C \18\.. 28 days.
65. Sulfate.......................... P, FP, G............... Cool, <=6 [deg]C \18\.. 28 days.
66. Sulfide.......................... P, FP, G............... Cool, <=6 [deg]C,\18\ 7 days.
add zinc acetate plus
sodium hydroxide to pH
9.
67. Sulfite.......................... P, FP, G............... None required.......... Analyze within 15
minutes.
68. Surfactants...................... P, FP, G............... Cool, <=6 [deg]C \18\.. 48 hours.
69. Temperature...................... P, FP, G............... None required.......... Analyze within 15
minutes.
73. Turbidity........................ P, FP, G............... Cool, <=6 [deg]C \18\.. 48 hours.
----------------------------------------------------------------------------------------------------------------
[[Page 67]]
Table IC--Organic Tests \8\
----------------------------------------------------------------------------------------------------------------
13, 18-20, 22, 24, 25, 27,28, 34-37, G, FP-lined septum..... Cool, <=6 [deg]C,\18\ 14 days.
39-43, 45-47, 56, 76, 104, 105, 108- 0.008% Na2S2O3,\5\ HCl
111, 113. Purgeable Halocarbons. to pH 2.
26. 2-Chloroethylvinyl ether......... G, FP-lined septum..... Cool, <=6 [deg]C,\18\ 14 days.
0.008% Na2S2O3\5\.
6, 57, 106. Purgeable aromatic G, FP-lined septum..... Cool, <=6 [deg]C,\18\ 14 days.\9\
hydrocarbons. 0.008% Na2S2O3,\5\ HCl
to pH 2 \9\.
3, 4. Acrolein and acrylonitrile..... G, FP-lined septum..... Cool, <=6 [deg]C,\18\ 14 days.\10\
0.008% Na2S2O3, pH to
4-5 \10\.
23, 30, 44, 49, 53, 77, 80, 81, 98, G, FP-lined cap........ Cool, <=6 [deg]C,\18\ 7 days until
100, 112. Phenols \11\. 0.008% Na2S2O3. extraction, 40 days
after extraction.
7, 38. Benzidines 11 12.............. G, FP-lined cap........ Cool, <=6 [deg]C,\18\ 7 days until
0.008% Na2S2O3\5\. extraction.\13\
14, 17, 48, 50-52. Phthalate esters G, FP-lined cap........ Cool, <=6 [deg]C \18\.. 7 days until
\11\. extraction, 40 days
after extraction.
82-84. Nitrosamines 11 14............ G, FP-lined cap........ Cool, <=6 [deg]C,\18\ 7 days until
store in dark, 0.008% extraction, 40 days
Na2S2O3 \5\. after extraction.
88-94. PCBs \11\..................... G, FP-lined cap........ Cool, <=6 [deg]C \18\.. 1 year until
extraction, 1 year
after extraction.
54, 55, 75, 79. Nitroaromatics and G, FP-lined cap........ Cool, <=6 [deg]C,\18\ 7 days until
isophorone \11\. store in dark, 0.008% extraction, 40 days
Na2S2O3 \5\. after extraction.
1, 2, 5, 8-12, 32, 33, 58, 59, 74, G, FP-lined cap........ Cool, <=6 [deg]C,\18\ 7 days until
78, 99, 101. Polynuclear aromatic store in dark, 0.008% extraction, 40 days
hydrocarbons \11\. Na2S2O3 \5\. after extraction.
15, 16, 21, 31, 87. Haloethers \11\.. G, FP-lined cap........ Cool, <=6 [deg]C,\18\ 7 days until
0.008% Na2S2O3 \5\. extraction, 40 days
after extraction.
29, 35-37, 63-65, 107. Chlorinated G, FP-lined cap........ Cool, <=6 [deg]C \18\.. 7 days until
hydrocarbons \11\. extraction, 40 days
after extraction.
60-62, 66-72, 85, 86, 95-97, 102, G...................... See footnote 11........ See footnote 11.
103. CDDs/CDFs \11\.
Aqueous Samples: Field and Lab G...................... Cool, <=6 [deg]C,\18\ 1 year.
Preservation. 0.008% Na2S2O3,\5\ pH
<9.
Solids and Mixed-Phase Samples: G...................... Cool, <=6 [deg]C \18\.. 7 days.
Field Preservation.
Tissue Samples: Field G...................... Cool, <=6 [deg]C \18\.. 24 hours.
Preservation.
Solids, Mixed-Phase, and Tissue G...................... Freeze, <=-10 [deg]C... 1 year.
Samples: Lab Preservation.
114-118. Alkylated phenols........... G...................... Cool, <6 [deg]C, H2SO4 28 days until
to pH <2. extraction, 40 days
after extraction.
119. Adsorbable Organic Halides (AOX) G...................... Cool, <6 [deg]C, 0.008% Hold at least 3 days,
Na2S2O3, HNO3 to pH <2. but not more than 6
months.
120. Chlorinated Phenolics........... G, FP-lined cap........ Cool, <6 [deg]C, 0.008% 30 days until
Na2S2O3, H2SO4 to pH acetylation, 30 days
<2. after acetylation.
----------------------------------------------------------------------------------------------------------------
Table ID--Pesticides Tests
----------------------------------------------------------------------------------------------------------------
1-70. Pesticides \11\................ G, FP-lined cap........ Cool, <=6 [deg]C,\18\ 7 days until
pH 5-9 \15\. extraction, 40 days
after extraction.
----------------------------------------------------------------------------------------------------------------
Table IE--Radiological Tests
----------------------------------------------------------------------------------------------------------------
1-5. Alpha, beta, and radium......... P, FP, G............... HNO3 to pH <2.......... 6 months.
----------------------------------------------------------------------------------------------------------------
Table IH--Bacterial Tests
----------------------------------------------------------------------------------------------------------------
1-4. Coliform, total, fecal.......... PA, G.................. Cool, <10 [deg]C, 8 hours.22 23
0.008% Na2S2O3\5\.
5. E. coli........................... PA, G.................. Cool, <10 [deg]C, 0. 8 hours.\22\
008% Na2S2O3 \5\.
6. Fecal streptococci................ PA, G.................. Cool, <10 [deg]C, 8 hours.\22\
0.008% Na2S2O3 \5\.
7. Enterococci....................... PA, G.................. Cool, <10 [deg]C, 0. 8 hours.\22\
008% Na2S2O3 \5\.
----------------------------------------------------------------------------------------------------------------
Table IH--Protozoan Tests
----------------------------------------------------------------------------------------------------------------
8. Cryptosporidium................... LDPE; field filtration. 1-10 [deg]C............ 96 hours.\21\
[[Page 68]]
9. Giardia........................... LDPE; field filtration. 1-10 [deg]C............ 96 hours.\21\
----------------------------------------------------------------------------------------------------------------
\1\ ``P'' is for polyethylene; ``FP'' is fluoropolymer (polytetrafluoroethylene (PTFE); Teflon[supreg]), or
other fluoropolymer, unless stated otherwise in this Table II; ``G'' is glass; ``PA'' is any plastic that is
made of a sterilizable material (polypropylene or other autoclavable plastic); ``LDPE'' is low density
polyethylene.
\2\ Except where noted in this Table II and the method for the parameter, preserve each grab sample within 15
minutes of collection. For a composite sample collected with an automated sample (e.g., using a 24-hour
composite sample; see 40 CFR 122.21(g)(7)(i) or 40 CFR part 403, appendix E), refrigerate the sample at <=6
[deg]C during collection unless specified otherwise in this Table II or in the method(s). For a composite
sample to be split into separate aliquots for preservation and/or analysis, maintain the sample at <=6 [deg]C,
unless specified otherwise in this Table II or in the method(s), until collection, splitting, and preservation
is completed. Add the preservative to the sample container prior to sample collection when the preservative
will not compromise the integrity of a grab sample, a composite sample, or aliquot split from a composite
sample within 15 minutes of collection. If a composite measurement is required but a composite sample would
compromise sample integrity, individual grab samples must be collected at prescribed time intervals (e.g., 4
samples over the course of a day, at 6-hour intervals). Grab samples must be analyzed separately and the
concentrations averaged. Alternatively, grab samples may be collected in the field and composited in the
laboratory if the compositing procedure produces results equivalent to results produced by arithmetic
averaging of results of analysis of individual grab samples. For examples of laboratory compositing
procedures, see EPA Method 1664 Rev. A (oil and grease) and the procedures at 40 CFR 141.24(f)(14)(iv) and (v)
(volatile organics).
\3\ When any sample is to be shipped by common carrier or sent via the U.S. Postal Service, it must comply with
the Department of Transportation Hazardous Materials Regulations (49 CFR part 172). The person offering such
material for transportation is responsible for ensuring such compliance. For the preservation requirement of
Table II, the Office of Hazardous Materials, Materials Transportation Bureau, Department of Transportation has
determined that the Hazardous Materials Regulations do not apply to the following materials: Hydrochloric acid
(HCl) in water solutions at concentrations of 0.04% by weight or less (pH about 1.96 or greater; Nitric acid
(HNO3) in water solutions at concentrations of 0.15% by weight or less (pH about 1.62 or greater); Sulfuric
acid (H2SO4) in water solutions at concentrations of 0.35% by weight or less (pH about 1.15 or greater); and
Sodium hydroxide (NaOH) in water solutions at concentrations of 0.080% by weight or less (pH about 12.30 or
less).
\4\ Samples should be analyzed as soon as possible after collection. The times listed are the maximum times that
samples may be held before the start of analysis and still be considered valid. Samples may be held for longer
periods only if the permittee or monitoring laboratory have data on file to show that, for the specific types
of samples under study, the analytes are stable for the longer time, and has received a variance from the
Regional ATP Coordinator under Sec. 136.3(e). For a grab sample, the holding time begins at the time of
collection. For a composite sample collected with an automated sampler (e.g., using a 24-hour composite
sampler; see 40 CFR 122.21(g)(7)(i) or 40 CFR part 403, appendix E), the holding time begins at the time of
the end of collection of the composite sample. For a set of grab samples composited in the field or
laboratory, the holding time begins at the time of collection of the last grab sample in the set. Some samples
may not be stable for the maximum time period given in the table. A permittee or monitoring laboratory is
obligated to hold the sample for a shorter time if it knows that a shorter time is necessary to maintain
sample stability. See Sec. 136.3(e) for details. The date and time of collection of an individual grab
sample is the date and time at which the sample is collected. For a set of grab samples to be composited, and
that are all collected on the same calendar date, the date of collection is the date on which the samples are
collected. For a set of grab samples to be composited, and that are collected across two calendar dates, the
date of collection is the dates of the two days; e.g., November 14-15. For a composite sample collected
automatically on a given date, the date of collection is the date on which the sample is collected. For a
composite sample collected automatically, and that is collected across two calendar dates, the date of
collection is the dates of the two days; e.g., November 14-15. For static-renewal toxicity tests, each grab or
composite sample may also be used to prepare test solutions for renewal at 24 h, 48 h, and/or 72 h after first
use, if stored at 0-6 [deg]C, with minimum head space.
\5\ ASTM D7365-09a specifies treatment options for samples containing oxidants (e.g., chlorine) for cyanide
analyses. Also, Section 9060A of Standard Methods for the Examination of Water and Wastewater (20th and 21st
editions) addresses dechlorination procedures for microbiological analyses.
\6\ Sampling, preservation and mitigating interferences in water samples for analysis of cyanide are described
in ASTM D7365-09a. There may be interferences that are not mitigated by the analytical test methods or D7365-
09a. Any technique for removal or suppression of interference may be employed, provided the laboratory
demonstrates that it more accurately measures cyanide through quality control measures described in the
analytical test method. Any removal or suppression technique not described in D7365-09a or the analytical test
method must be documented along with supporting data.
\7\ For dissolved metals, filter grab samples within 15 minutes of collection and before adding preservatives.
For a composite sample collected with an automated sampler (e.g., using a 24-hour composite sampler; see 40
CFR 122.21(g)(7)(i) or 40 CFR part 403, appendix E), filter the sample within 15 minutes after completion of
collection and before adding preservatives. If it is known or suspected that dissolved sample integrity will
be compromised during collection of a composite sample collected automatically over time (e.g., by interchange
of a metal between dissolved and suspended forms), collect and filter grab samples to be composited (footnote
2) in place of a composite sample collected automatically.
\8\ Guidance applies to samples to be analyzed by GC, LC, or GC/MS for specific compounds.
\9\ If the sample is not adjusted to pH 2, then the sample must be analyzed within seven days of sampling.
\10\ The pH adjustment is not required if acrolein will not be measured. Samples for acrolein receiving no pH
adjustment must be analyzed within 3 days of sampling.
\11\ When the extractable analytes of concern fall within a single chemical category, the specified preservative
and maximum holding times should be observed for optimum safeguard of sample integrity (i.e., use all
necessary preservatives and hold for the shortest time listed). When the analytes of concern fall within two
or more chemical categories, the sample may be preserved by cooling to <=6 [deg]C, reducing residual chlorine
with 0.008% sodium thiosulfate, storing in the dark, and adjusting the pH to 6-9; samples preserved in this
manner may be held for seven days before extraction and for forty days after extraction. Exceptions to this
optional preservation and holding time procedure are noted in footnote 5 (regarding the requirement for
thiosulfate reduction), and footnotes 12, 13 (regarding the analysis of benzidine).
\12\ If 1,2-diphenylhydrazine is likely to be present, adjust the pH of the sample to 4.0
0.2 to prevent rearrangement to benzidine.
\13\ Extracts may be stored up to 30 days at <0 [deg]C.
\14\ For the analysis of diphenylnitrosamine, add 0.008% Na2S2O3 and adjust pH to 7-10 with NaOH within 24 hours
of sampling.
\15\ The pH adjustment may be performed upon receipt at the laboratory and may be omitted if the samples are
extracted within 72 hours of collection. For the analysis of aldrin, add 0.008% Na2S2O3.
\16\ Place sufficient ice with the samples in the shipping container to ensure that ice is still present when
the samples arrive at the laboratory. However, even if ice is present when the samples arrive, immediately
measure the temperature of the samples and confirm that the preservation temperature maximum has not been
exceeded. In the isolated cases where it can be documented that this holding temperature cannot be met, the
permittee can be given the option of on-site testing or can request a variance. The request for a variance
should include supportive data which show that the toxicity of the effluent samples is not reduced because of
the increased holding temperature. Aqueous samples must not be frozen. Hand-delivered samples used on the day
of collection do not need to be cooled to 0 to 6 [deg]C prior to test initiation.
[[Page 69]]
\17\ Samples collected for the determination of trace level mercury (<100 ng/L) using EPA Method 1631 must be
collected in tightly-capped fluoropolymer or glass bottles and preserved with BrCl or HCl solution within 48
hours of sample collection. The time to preservation may be extended to 28 days if a sample is oxidized in the
sample bottle. A sample collected for dissolved trace level mercury should be filtered in the laboratory
within 24 hours of the time of collection. However, if circumstances preclude overnight shipment, the sample
should be filtered in a designated clean area in the field in accordance with procedures given in Method 1669.
If sample integrity will not be maintained by shipment to and filtration in the laboratory, the sample must be
filtered in a designated clean area in the field within the time period necessary to maintain sample
integrity. A sample that has been collected for determination of total or dissolved trace level mercury must
be analyzed within 90 days of sample collection.
\18\ Aqueous samples must be preserved at <=6 [deg]C, and should not be frozen unless data demonstrating that
sample freezing does not adversely impact sample integrity is maintained on file and accepted as valid by the
regulatory authority. Also, for purposes of NPDES monitoring, the specification of ``<= [deg]C'' is used in
place of the ``4 [deg]C'' and ``<4 [deg]C'' sample temperature requirements listed in some methods. It is not
necessary to measure the sample temperature to three significant figures (1/100th of 1 degree); rather, three
significant figures are specified so that rounding down to 6 [deg]C may not be used to meet the <=6 [deg]C
requirement. The preservation temperature does not apply to samples that are analyzed immediately (less than
15 minutes).
\19\ An aqueous sample may be collected and shipped without acid preservation. However, acid must be added at
least 24 hours before analysis to dissolve any metals that adsorb to the container walls. If the sample must
be analyzed within 24 hours of collection, add the acid immediately (see footnote 2). Soil and sediment
samples do not need to be preserved with acid. The allowances in this footnote supersede the preservation and
holding time requirements in the approved metals methods.
\20\ To achieve the 28-day holding time, use the ammonium sulfate buffer solution specified in EPA Method 218.6.
The allowance in this footnote supersedes preservation and holding time requirements in the approved
hexavalent chromium methods, unless this supersession would compromise the measurement, in which case
requirements in the method must be followed.
\21\ Holding time is calculated from time of sample collection to elution for samples shipped to the laboratory
in bulk and calculated from the time of sample filtration to elution for samples filtered in the field.
\22\ Sample analysis should begin as soon as possible after receipt; sample incubation must be started no later
than 8 hours from time of collection.
\23\ For fecal coliform samples for sewage sludge (biosolids) only, the holding time is extended to 24 hours for
the following sample types using either EPA Method 1680 (LTB-EC) or 1681 (A-1): Class A composted, Class B
aerobically digested, and Class B anaerobically digested.
\24\ The immediate filtration requirement in orthophosphate measurement is to assess the dissolved or bio-
available form of orthophosphorus (i.e., that which passes through a 0.45-micron filter), hence the
requirement to filter the sample immediately upon collection (i.e., within 15 minutes of collection).
[38 FR 28758, Oct. 16, 1973]
Editorial Note: For Federal Register citations affecting Sec.
136.3, see the List of CFR Sections Affected, which appears in the
Finding Aids section of the printed volume and at www.fdsys.gov.
Sec. 136.4 Application for and approval of alternate test procedures
for nationwide use.
(a) A written application for review of an alternate test procedure
(alternate method) for nationwide use may be made by letter via email or
by hard copy in triplicate to the National Alternate Test Procedure
(ATP) Program Coordinator (National Coordinator), Office of Science and
Technology (4303T), Office of Water, U.S. Environmental Protection
Agency, 1200 Pennsylvania Ave. NW., Washington, DC 20460. Any
application for an ATP under this paragraph (a) shall:
(1) Provide the name and address of the responsible person or firm
making the application.
(2) Identify the pollutant(s) or parameter(s) for which nationwide
approval of an alternate test procedure is being requested.
(3) Provide a detailed description of the proposed alternate test
procedure, together with references to published or other studies
confirming the general applicability of the alternate test procedure for
the analysis of the pollutant(s) or parameter(s) in wastewater
discharges from representative and specified industrial or other
categories.
(4) Provide comparability data for the performance of the proposed
alternative test procedure compared to the performance of the reference
method.
(b) The National Coordinator may request additional information and
analyses from the applicant in order to evaluate whether the alternate
test procedure satisfies the applicable requirements of this part.
(c) Approval for nationwide use. (1) After a review of the
application and any additional analyses requested from the applicant,
the National Coordinator will notify the applicant, in writing, of
whether the National Coordinator will recommend approval or disapproval
of the alternate test procedure for nationwide use in CWA programs. If
the application is not recommended for approval, the National
Coordinator may specify what additional information might lead to a
reconsideration of the application and notify the Regional Alternate
Test Procedure Coordinators of the disapproval recommendation. Based on
the National Coordinator's recommended disapproval of a proposed
[[Page 70]]
alternate test procedure and an assessment of any current approvals for
limited uses for the unapproved method, the Regional ATP Coordinator may
decide to withdraw approval of the method for limited use in the Region.
(2) Where the National Coordinator has recommended approval of an
applicant's request for nationwide use of an alternate test procedure,
the National Coordinator will notify the applicant. The National
Coordinator will also notify the Regional ATP Coordinators that they may
consider approval of this alternate test procedure for limited use in
their Regions based on the information and data provided in the
application until the alternate test procedure is approved by
publication in a final rule in the Federal Register.
(3) EPA will propose to amend this part to include the alternate
test procedure in Sec. 136.3. EPA shall make available for review all
the factual bases for its proposal, including the method, any
performance data submitted by the applicant and any available EPA
analysis of those data.
(4) Following public comment, EPA shall publish in the Federal
Register a final decision on whether to amend this part to include the
alternate test procedure as an approved analytical method for nationwide
use.
(5) Whenever the National Coordinator has recommended approval of an
applicant's ATP request for nationwide use, any person may request an
approval of the method for limited use under Sec. 136.5 from the EPA
Region.
[77 FR 29809, May 18, 2012, as amended at 82 FR 40874, Aug. 28, 2017]
Sec. 136.5 Approval of alternate test procedures for limited use.
(a) Any person may request the Regional ATP Coordinator to approve
the use of an alternate test procedure in the Region.
(b) When the request for the use of an alternate test procedure
concerns use in a State with an NPDES permit program approved pursuant
to section 402 of the Act, the requestor shall first submit an
application for limited use to the Director of the State agency having
responsibility for issuance of NPDES permits within such State (i.e.,
permitting authority). The Director will forward the application to the
Regional ATP Coordinator with a recommendation for or against approval.
(c) Any application for approval of an alternate test procedure for
limited use may be made by letter, email or by hard copy. The
application shall include the following:
(1) Provide the name and address of the applicant and the applicable
ID number of the existing or pending permit(s) and issuing agency for
which use of the alternate test procedure is requested, and the
discharge serial number.
(2) Identify the pollutant or parameter for which approval of an
alternate test procedure is being requested.
(3) Provide justification for using testing procedures other than
those specified in Tables IA through IH of Sec. 136.3, or in the NPDES
permit.
(4) Provide a detailed description of the proposed alternate test
procedure, together with references to published studies of the
applicability of the alternate test procedure to the effluents in
question.
(5) Provide comparability data for the performance of the proposed
alternate test procedure compared to the performance of the reference
method.
(d) Approval for limited use. (1) The Regional ATP Coordinator will
review the application and notify the applicant and the appropriate
State agency of approval or rejection of the use of the alternate test
procedure. The approval may be restricted to use only with respect to a
specific discharge or facility (and its laboratory) or, at the
discretion of the Regional ATP Coordinator, to all dischargers or
facilities (and their associated laboratories) specified in the approval
for the Region. If the application is not approved, the Regional ATP
Coordinator shall specify what additional information might lead to a
reconsideration of the application.
(2) The Regional ATP Coordinator will forward a copy of every
approval and rejection notification to the National Alternate Test
Procedure Coordinator.
[77 FR 29809, May 18, 2012, as amended at 82 FR 40875, Aug. 28, 2017]
[[Page 71]]
Sec. 136.6 Method modifications and analytical requirements.
(a) Definitions of terms used in this section--(1) Analyst means the
person or laboratory using a test procedure (analytical method) in this
part.
(2) Chemistry of the method means the reagents and reactions used in
a test procedure that allow determination of the analyte(s) of interest
in an environmental sample.
(3) Determinative technique means the way in which an analyte is
identified and quantified (e.g., colorimetry, mass spectrometry).
(4) Equivalent performance means that the modified method produces
results that meet or exceed the QC acceptance criteria of the approved
method.
(5) Method-defined analyte means an analyte defined solely by the
method used to determine the analyte. Such an analyte may be a physical
parameter, a parameter that is not a specific chemical, or a parameter
that may be comprised of a number of substances. Examples of such
analytes include temperature, oil and grease, total suspended solids,
total phenolics, turbidity, chemical oxygen demand, and biochemical
oxygen demand.
(6) QC means ``quality control.''
(b) Method modifications. (1) If the underlying chemistry and
determinative technique in a modified method are essentially the same as
an approved Part 136 method, then the modified method is an equivalent
and acceptable alternative to the approved method provided the
requirements of this section are met. However, those who develop or use
a modification to an approved (Part 136) method must document that the
performance of the modified method, in the matrix to which the modified
method will be applied, is equivalent to the performance of the approved
method. If such a demonstration cannot be made and documented, then the
modified method is not an acceptable alternative to the approved method.
Supporting documentation must, if applicable, include the routine
initial demonstration of capability and ongoing QC including
determination of precision and accuracy, detection limits, and matrix
spike recoveries. Initial demonstration of capability typically includes
analysis of four replicates of a mid-level standard and a method
detection limit study. Ongoing quality control typically includes method
blanks, mid-level laboratory control samples, and matrix spikes (QC is
as specified in the method). The method is considered equivalent if the
quality control requirements in the reference method are achieved. Where
the laboratory is using a vendor-supplied method, it is the QC criteria
in the reference method, not the vendor's method, that must be met to
show equivalency. Where a sample preparation step is required (i.e.,
digestion, distillation), QC tests are to be run using standards treated
in the same way as the samples. The method user's Standard Operating
Procedure (SOP) must clearly document the modifications made to the
reference method. Examples of allowed method modifications are listed in
this section. If the method user is uncertain whether a method
modification is allowed, the Regional ATP Coordinator or Director should
be contacted for approval prior to implementing the modification. The
method user should also complete necessary performance checks to verify
that acceptable performance is achieved with the method modification
prior to analyses of compliance samples.
(2) Requirements. The modified method must meet or exceed
performance of the approved method(s) for the analyte(s) of interest, as
documented by meeting the initial and ongoing quality control
requirements in the method.
(i) Requirements for establishing equivalent performance. If the
approved method contains QC tests and QC acceptance criteria, the
modified method must use these QC tests and the modified method must
meet the QC acceptance criteria with the following conditions:
(A) The analyst may only rely on QC tests and QC acceptance criteria
in a method if it includes wastewater matrix QC tests and QC acceptance
criteria (e.g., matrix spikes) and both initial (start-up) and ongoing
QC tests and QC acceptance criteria.
(B) If the approved method does not contain QC tests and QC
acceptance criteria or if the QC tests and QC acceptance criteria in the
method do not
[[Page 72]]
meet the requirements of this section, then the analyst must employ QC
tests published in the ``equivalent'' of a Part 136 method that has such
QC, or the essential QC requirements specified at 136.7, as applicable.
If the approved method is from a compendium or VCSB and the QA/QC
requirements are published in other parts of that organization's
compendium rather than within the Part 136 method then that part of the
organization's compendium must be used for the QC tests.
(C) In addition, the analyst must perform ongoing QC tests,
including assessment of performance of the modified method on the sample
matrix (e.g., analysis of a matrix spike/matrix spike duplicate pair for
every twenty samples), and analysis of an ongoing precision and recovery
sample (e.g., laboratory fortified blank or blank spike) and a blank
with each batch of 20 or fewer samples.
(D) If the performance of the modified method in the wastewater
matrix or reagent water does not meet or exceed the QC acceptance
criteria, the method modification may not be used.
(ii) Requirements for documentation. The modified method must be
documented in a method write-up or an addendum that describes the
modification(s) to the approved method prior to the use of the method
for compliance purposes. The write-up or addendum must include a
reference number (e.g., method number), revision number, and revision
date so that it may be referenced accurately. In addition, the
organization that uses the modified method must document the results of
QC tests and keep these records, along with a copy of the method write-
up or addendum, for review by an auditor.
(3) Restrictions. An analyst may not modify an approved Clean Water
Act analytical method for a method-defined analyte. In addition, an
analyst may not modify an approved method if the modification would
result in measurement of a different form or species of an analyte.
Changes in method procedures are not allowed if such changes would alter
the defined chemistry (i.e., method principle) of the unmodified method.
For example, phenol method 420.1 or 420.4 defines phenolics as ferric
iron oxidized compounds that react with 4-aminoantipyrine (4-AAP) at pH
10 after being distilled from acid solution. Because total phenolics
represents a group of compounds that all react at different efficiencies
with 4-AAP, changing test conditions likely would change the behavior of
these different phenolic compounds. An analyst may not modify any sample
collection, preservation, or holding time requirements of an approved
method. Such modifications to sample collection, preservation, and
holding time requirements do not fall within the scope of the
flexibility allowed at Sec. 136.6. Method flexibility refers to
modifications of the analytical procedures used for identification and
measurement of the analyte only and does not apply to sample collection,
preservation, or holding time procedures, which may only be modified as
specified in Sec. 136.3(e).
(4) Allowable changes. Except as noted under paragraph (b)(3) of
this section, an analyst may modify an approved test procedure
(analytical method) provided that the underlying reactions and
principles used in the approved method remain essentially the same, and
provided that the requirements of this section are met. If equal or
better performance can be obtained with an alternative reagent, then it
is allowed. A laboratory wishing to use these modifications must
demonstrate acceptable method performance by performing and documenting
all applicable initial demonstration of capability and ongoing QC tests
and meeting all applicable QC acceptance criteria as described in Sec.
136.7. Some examples of the allowed types of changes, provided the
requirements of this section are met include:
(i) Changes between manual method, flow analyzer, and discrete
instrumentation.
(ii) Changes in chromatographic columns or temperature programs.
(iii) Changes between automated and manual sample preparation, such
as digestions, distillations, and extractions; in-line sample
preparation is an acceptable form of automated sample preparation for
CWA methods.
(iv) In general, ICP-MS is a sensitive and selective detector for
metal analysis; however isobaric interference can
[[Page 73]]
cause problems for quantitative determination, as well as identification
based on the isotope pattern. Interference reduction technologies, such
as collision cells or reaction cells, are designed to reduce the effect
of spectroscopic interferences that may bias results for the element of
interest. The use of interference reduction technologies is allowed,
provided the method performance specifications relevant to ICP-MS
measurements are met.
(v) The use of EPA Method 200.2 or the sample preparation steps from
EPA Method 1638, including the use of closed-vessel digestion, is
allowed for EPA Method 200.8, provided the method performance
specifications relevant to the ICP-MS are met.
(vi) Changes in pH adjustment reagents. Changes in compounds used to
adjust pH are acceptable as long as they do not produce interference.
For example, using a different acid to adjust pH in colorimetric
methods.
(vii) Changes in buffer reagents are acceptable provided that the
changes do not produce interferences.
(viii) Changes in the order of reagent addition are acceptable
provided that the change does not alter the chemistry and does not
produce an interference. For example, using the same reagents, but
adding them in different order, or preparing them in combined or
separate solutions (so they can be added separately), is allowed,
provided reagent stability or method performance is equivalent or
improved.
(ix) Changes in calibration range (provided that the modified range
covers any relevant regulatory limit and the method performance
specifications for calibration are met).
(x) Changes in calibration model. (A) Linear calibration models do
not adequately fit calibration data with one or two inflection points.
For example, vendor-supplied data acquisition and processing software on
some instruments may provide quadratic fitting functions to handle such
situations. If the calibration data for a particular analytical method
routinely display quadratic character, using quadratic fitting functions
may be acceptable. In such cases, the minimum number of calibrators for
second order fits should be six, and in no case should concentrations be
extrapolated for instrument responses that exceed that of the most
concentrated calibrator. Examples of methods with nonlinear calibration
functions include chloride by SM4500-Cl-E-1997, hardness by EPA Method
130.1, cyanide by ASTM D6888 or OIA1677, Kjeldahl nitrogen by PAI-DK03,
and anions by EPA Method 300.0.
(B) As an alternative to using the average response factor, the
quality of the calibration may be evaluated using the Relative Standard
Error (RSE). The acceptance criterion for the RSE is the same as the
acceptance criterion for Relative Standard Deviation (RSD), in the
method. RSE is calculated as:
[GRAPHIC] [TIFF OMITTED] TR18MY12.000
Where:
x[min]i = Calculated concentration at level i
xi = Actual concentration of the calibration level i
n = Number of calibration points
p = Number of terms in the fitting equation (average = 1, linear = 2,
quadratic = 3)
(C) Using the RSE as a metric has the added advantage of allowing
the same numerical standard to be applied to the calibration model,
regardless of the form of the model. Thus, if a method states that the
RSD should be <=20% for the traditional linear model
[[Page 74]]
through the origin, then the RSE acceptance limit can remain <=20% as
well. Similarly, if a method provides an RSD acceptance limit of <=15%,
then that same figure can be used as the acceptance limit for the RSE.
The RSE may be used as an alternative to correlation coefficients and
coefficients of determination for evaluating calibration curves for any
of the methods at part 136. If the method includes a numerical criterion
for the RSD, then the same numerical value is used for the RSE. Some
older methods do not include any criterion for the calibration curve--
for these methods, if RSE is used the value should be <=20%. Note that
the use of the RSE is included as an alternative to the use of the
correlation coefficient as a measure of the suitability of a calibration
curve. It is not necessary to evaluate both the RSE and the correlation
coefficient.
(xi) Changes in equipment such as equipment from a vendor different
from the one specified in the method.
(xii) The use of micro or midi distillation apparatus in place of
macro distillation apparatus.
(xiii) The use of prepackaged reagents.
(xiv) The use of digital titrators and methods where the underlying
chemistry used for the determination is similar to that used in the
approved method.
(xv) Use of selected ion monitoring (SIM) mode for analytes that
cannot be effectively analyzed in full-scan mode and reach the required
sensitivity. False positives are more of a concern when using SIM
analysis, so at a minimum, one quantitation and two qualifying ions must
be monitored for each analyte (unless fewer than three ions with
intensity greater than 15% of the base peak are available). The ratio of
each of the two qualifying ions to the quantitation ion must be
evaluated and should agree with the ratio observed in an authentic
standard within 20 percent. Analyst judgment must
be applied to the evaluation of ion ratios because the ratios can be
affected by co-eluting compounds present in the sample matrix. The
signal-to-noise ratio of the least sensitive ion should be at least 3:1.
Retention time in the sample should match within 0.05 minute of an
authentic standard analyzed under identical conditions. Matrix
interferences can cause minor shifts in retention time and may be
evident as shifts in the retention times of the internal standards. The
total scan time should be such that a minimum of eight scans are
obtained per chromatographic peak.
(xvi) Changes are allowed in purge-and-trap sample volumes or
operating conditions. Some examples are:
(A) Changes in purge time and purge-gas flow rate. A change in purge
time and purge-gas flow rate is allowed provided that sufficient total
purge volume is used to achieve the required minimum detectible
concentration and calibration range for all compounds. In general, a
purge rate in the range 20-200 mL/min and a total purge volume in the
range 240-880 mL are recommended.
(B) Use of nitrogen or helium as a purge gas, provided that the
required sensitivities for all compounds are met.
(C) Sample temperature during the purge state. Gentle heating of the
sample during purging (e.g., 40 [deg]C) increases purging efficiency of
hydrophilic compounds and may improve sample-to-sample repeatability
because all samples are purged under precisely the same conditions.
(D) Trap sorbent. Any trap design is acceptable, provided that the
data acquired meet all QC criteria.
(E) Changes to the desorb time. Shortening the desorb time (e.g.,
from4 minutes to 1 minute) may not affect compound recoveries, and can
shorten overall cycle time and significantly reduce the amount of water
introduced to the analytical system, thus improving the precision of
analysis, especially for water-soluble analytes. A desorb time of four
minutes is recommended, however a shorter desorb time may be used,
provided that all QC specifications in the method are met.
(F) Use of water management techniques is allowed. Water is always
collected on the trap along with the analytes and is a significant
interference for analytical systems (GC and GC/MS). Modern water
management techniques (e.g., dry purge or condensation points) can
remove moisture from
[[Page 75]]
the sample stream and improve analytical performance.
(xvii) If the characteristics of a wastewater matrix prevent
efficient recovery of organic pollutants and prevent the method from
meeting QC requirements, the analyst may attempt to resolve the issue by
adding salts to the sample, provided that such salts do not react with
or introduce the target pollutant into the sample (as evidenced by the
analysis of method blanks, laboratory control samples, and spiked
samples that also contain such salts), and that all requirements of
paragraph (b)(2) of this section are met. Samples having residual
chlorine or other halogen must be dechlorinated prior to the addition of
such salts.
(xviii) If the characteristics of a wastewater matrix result in poor
sample dispersion or reagent deposition on equipment and prevent the
analyst from meeting QC requirements, the analyst may attempt to resolve
the issue by adding a inert surfactant that does not affect the
chemistry of the method, such as Brij-35 or sodium dodecyl sulfate
(SDS), provided that such surfactant does not react with or introduce
the target pollutant into the sample (as evidenced by the analysis of
method blanks, laboratory control samples, and spiked samples that also
contain such surfactant) and that all requirements of paragraph (b)(1)
and (b)(2) of this section are met. Samples having residual chlorine or
other halogen must be dechlorinated prior to the addition of such
surfactant.
(xix) The use of gas diffusion (using pH change to convert the
analyte to gaseous form and/or heat to separate an analyte contained in
steam from the sample matrix) across a hydrophobic semi-permeable
membrane to separate the analyte of interest from the sample matrix may
be used in place of manual or automated distillation in methods for
analysis such as ammonia, total cyanide, total Kjeldahl nitrogen, and
total phenols. These procedures do not replace the digestion procedures
specified in the approved methods and must be used in conjunction with
those procedures.
(xx) Changes in equipment operating parameters such as the
monitoring wavelength of a colorimeter or the reaction time and
temperature as needed to achieve the chemical reactions defined in the
unmodified CWA method. For example, molybdenum blue phosphate methods
have two absorbance maxima, one at about 660 nm and another at about 880
nm. The former is about 2.5 times less sensitive than the latter.
Wavelength choice provides a cost-effective, dilution-free means to
increase sensitivity of molybdenum blue phosphate methods.
(xxi) Interchange of oxidants, such as the use of titanium oxide in
UV-assisted automated digestion of TOC and total phosphorus, as long as
complete oxidation can be demonstrated.
(xxii) Use of an axially viewed torch with Method 200.7.
(c) The permittee must notify their permitting authority of the
intent to use a modified method. Such notification should be of the form
``Method xxx has been modified within the flexibility allowed in 40 CFR
136.6.'' The permittee may indicate the specific paragraph of Sec.
136.6 allowing the method modification. Specific details of the
modification need not be provided, but must be documented in the
Standard Operating Procedure (SOP) and maintained by the analytical
laboratory that performs the analysis.
[77 FR 29810, May 18, 2012, as amended at 82 FR 40875, Aug. 28, 2017]
Sec. 136.7 Quality assurance and quality control.
The permittee/laboratory shall use suitable QA/QC procedures when
conducting compliance analyses with any part 136 chemical method or an
alternative method specified by the permitting authority. These QA/QC
procedures are generally included in the analytical method or may be
part of the methods compendium for approved Part 136 methods from a
consensus organization. For example, Standard Methods contains QA/QC
procedures in the Part 1000 section of the Standard Methods Compendium.
The permittee/laboratory shall follow these QA/QC procedures, as
described in the method or methods compendium. If the method lacks QA/QC
procedures, the permittee/laboratory has the following options to comply
with the QA/QC requirements:
[[Page 76]]
(a) Refer to and follow the QA/QC published in the ``equivalent''
EPA method for that parameter that has such QA/QC procedures;
(b) Refer to the appropriate QA/QC section(s) of an approved part
136 method from a consensus organization compendium;
(c)(1) Incorporate the following twelve quality control elements,
where applicable, into the laboratory's documented standard operating
procedure (SOP) for performing compliance analyses when using an
approved part 136 method when the method lacks such QA/QC procedures.
One or more of the twelve QC elements may not apply to a given method
and may be omitted if a written rationale is provided indicating why the
element(s) is/are inappropriate for a specific method.
(i) Demonstration of Capability (DOC);
(ii) Method Detection Limit (MDL);
(iii) Laboratory reagent blank (LRB), also referred to as method
blank (MB);
(iv) Laboratory fortified blank (LFB), also referred to as a spiked
blank, or laboratory control sample (LCS);
(v) Matrix spike (MS) and matrix spike duplicate (MSD), or
laboratory fortified matrix (LFM) and LFM duplicate, may be used for
suspected matrix interference problems to assess precision;
(vi) Internal standards (for GC/MS analyses), surrogate standards
(for organic analysis) or tracers (for radiochemistry);
(vii) Calibration (initial and continuing), also referred to as
initial calibration verification (ICV) and continuing calibration
verification (CCV);
(viii) Control charts (or other trend analyses of quality control
results);
(ix) Corrective action (root cause analysis);
(x) QC acceptance criteria;
(xi) Definitions of preparation and analytical batches that may
drive QC frequencies; and
(xii) Minimum frequency for conducting all QC elements.
(2) These twelve quality control elements must be clearly documented
in the written standard operating procedure for each analytical method
not containing QA/QC procedures, where applicable.
[77 FR 29813, May 18, 2012]
Sec. Appendix A to Part 136--Methods for Organic Chemical Analysis of
Municipal and Industrial Wastewater
Method 601--Purgeable Halocarbons
1. Scope and Application
1.1 This method covers the determination of 29 purgeable
halocarbons.
The following parameters may be determined by this method:
------------------------------------------------------------------------
STORET
Parameter No. CAS No.
------------------------------------------------------------------------
Bromodichloromethane........................... 32101 75-27-4
Bromoform...................................... 32104 75-25-2
Bromomethane................................... 34413 74-83-9
Carbon tetrachloride........................... 32102 56-23-5
Chlorobenzene.................................. 34301 108-90-7
Chloroethane................................... 34311 75-00-3
2-Chloroethylvinyl ether....................... 34576 100-75-8
Chloroform..................................... 32106 67-66-3
Chloromethane.................................. 34418 74-87-3
Dibromochloromethane........................... 32105 124-48-1
1,2-Dichlorobenzene............................ 34536 95-50-1
1,3-Dichlorobenzene............................ 34566 541-73-1
1,4-Dichlorobenzene............................ 34571 106-46-7
Dichlorodifluoromethane........................ 34668 75-71-8
1,1-Dichloroethane............................. 34496 75-34-3
1,2-Dichloroethane............................. 34531 107-06-2
1,1-Dichloroethane............................. 34501 75-35-4
trans-1,2-Dichloroethene....................... 34546 156-60-5
1,2-Dichloropropane............................ 34541 78-87-5
cis-1,3-Dichloropropene........................ 34704 10061-01-5
trans-1,3-Dichloropropene...................... 34699 10061-02-6
Methylene chloride............................. 34423 75-09-2
1,1,2,2-Tetrachloroethane...................... 34516 79-34-5
Tetrachloroethene.............................. 34475 127-18-4
1,1,1-Trichloroethane.......................... 34506 71-55-6
1,1,2-Trichloroethane.......................... 34511 79-00-5
Tetrachloroethene.............................. 39180 79-01-6
Trichlorofluoromethane......................... 34488 75-69-4
Vinyl chloride................................. 39715 75-01-4
------------------------------------------------------------------------
1.2 This is a purge and trap gas chromatographic (GC) method
applicable to the determination of the compounds listed above in
municipal and industrial discharges as provided under 40 CFR 136.1. When
this method is used to analyze unfamiliar samples for any or all of the
compounds above, compound identifications should be supported by at
least one additional qualitative technique. This method describes
analytical conditions for a second gas chromatographic column that can
be used to confirm measurements made with the primary column. Method 624
provides gas chromatograph/mass spectrometer (GC/MS) conditions
appropriate for the qualitative and quantitative confirmation of results
for most of the parameters listed above.
1.3 The method detection limit (MDL, defined in Section 12.1) \1\
for each parameter is
[[Page 77]]
listed in Table 1. The MDL for a specific wastewater may differ from
those listed, depending upon the nature of interferences in the sample
matrix.
1.4 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.5 This method is restricted to use by or under the supervision of
analysts experienced in the operation of a purge and trap system and a
gas chromatograph and in the interpretation of gas chromatograms. Each
analyst must demonstrate the ability to generate acceptable results with
this method using the procedure described in Section 8.2.
2. Summary of Method
2.1 An inert gas is bubbled through a 5-mL water sample contained in
a specially-designed purging chamber at ambient temperature. The
halocarbons are efficiently transferred from the aqueous phase to the
vapor phase. The vapor is swept through a sorbent trap where the
halocarbons are trapped. After purging is completed, the trap is heated
and backflushed with the inert gas to desorb the halocarbons onto a gas
chromatographic column. The gas chromatograph is temperature programmed
to separate the halocarbons which are then detected with a halide-
specific detector. \2 3\
2.2 The method provides an optional gas chromatographic column that
may be helpful in resolving the compounds of interest from interferences
that may occur.
3. Interferences
3.1 Impurities in the purge gas and organic compounds outgassing
from the plumbing ahead of the trap account for the majority of
contamination problems. The analytical system must be demonstrated to be
free from contamination under the conditions of the analysis by running
laboratory reagent blanks as described in Section 8.1.3. The use of non-
Teflon plastic tubing, non-Teflon thread sealants, or flow controllers
with rubber components in the purge and trap system should be avoided.
3.2 Samples can be contaminated by diffusion of volatile organics
(particularly fluorocarbons and methylene chloride) through the septum
seal ilto the sample during shipment and storage. A field reagent blank
prepared from reagent water and carried through the sampling and
handling protocol can serve as a check on such contamination.
3.3 Contamination by carry-over can occur whenever high level and
low level samples are sequentially analyzed. To reduce carry-over, the
purging device and sample syringe must be rinsed with reagent water
between sample analyses. Whenever an unusually concentrated sample is
encountered, it should be followed by an analysis of reagent water to
check for cross contamination. For samples containing large amounts of
water-soluble materials, suspended solids, high boiling compounds or
high organohalide levels, it may be necessary to wash out the purging
device with a detergent solution, rinse it with distilled water, and
then dry it in a 105 [deg]C oven between analyses. The trap and other
parts of the system are also subject to contamination; therefore,
frequent bakeout and purging of the entire system may be required.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified \4 6\ for
the information of the analyst.
4.2 The following parameters covered by this method have been
tentatively classified as known or suspected, human or mammalian
carcinogens: carbon tetrachloride, chloroform, 1,4-dichlorobenzene, and
vinyl chloride. Primary standards of these toxic compounds should be
prepared in a hood. A NIOSH/MESA approved toxic gas respirator should be
worn when the analyst handles high concentrations of these toxic
compounds.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete sampling.
5.1.1 Vial--25-mL capacity or larger, equipped with a screw cap with
a hole in the center (Pierce 13075 or equivalent). Detergent wash,
rinse with tap and distilled water, and dry at 105 [deg]C before use.
5.1.2 Septum--Teflon-faced silicone (Pierce 12722 or equivalent).
Detergent wash, rinse with tap and distilled water, and dry at 105
[deg]C for 1 h before use.
5.2 Purge and trap system--The purge and trap system consists of
three separate pieces of equipment: a purging device, trap, and
desorber. Several complete systems are now commercially available.
5.2.1 The purging device must be designed to accept 5-mL samples
with a water column at least 3 cm deep. The gaseous head space between
the water column and the trap must have a total volume of less than 15
mL. The
[[Page 78]]
purge gas must pass through the water column as finely divided bubbles
with a diameter of less than 3 mm at the origin. The purge gas must be
introduced no more than 5 mm from the base of the water column. The
purging device illustrated in Figure 1 meets these design criteria.
5.2.2 The trap must be at least 25 cm long and have an inside
diameter of at least 0.105 in. The trap must be packed to contain the
following minimum lengths of adsorbents: 1.0 cm of methyl silicone
coated packing (Section 6.3.3), 7.7 cm of 2,6-diphenylene oxide polymer
(Section 6.3.2), 7.7 cm of silica gel (Section 6.3.4), 7.7 cm of coconut
charcoal (Section 6.3.1). If it is not necessary to analyze for
dichlorodifluoromethane, the charcoal can be eliminated, and the polymer
section lengthened to 15 cm. The minimum specifications for the trap are
illustrated in Figure 2.
5.2.3 The desorber must be capable of rapidly heating the trap to
180 [deg]C. The polymer section of the trap should not be heated higher
than 180 [deg]C and the remaining sections should not exceed 200 [deg]C.
The desorber illustrated in Figure 2 meets these design criteria.
5.2.4 The purge and trap system may be assembled as a separate unit
or be coupled to a gas chromatograph as illustrated in Figures 3 and 4.
5.3 Gas chromatograph--An analytical system complete with a
temperature programmable gas chromatograph suitable for on-column
injection and all required accessories including syringes, analytical
columns, gases, detector, and strip-chart recorder. A data system is
recommended for measuring peak areas.
5.3.1 Column 1--8 ft long x 0.1 in. ID stainless steel or glass,
packed with 1% SP-1000 on Carbopack B (60/80 mesh) or equivalent. This
column was used to develop the method performance statements in Section
12. Guidelines for the use of alternate column packings are provided in
Section 10.1.
5.3.2 Column 2--6 ft long x 0.1 in. ID stainless steel or glass,
packed with chemically bonded n-octane on Porasil-C (100/120 mesh) or
equivalent.
5.3.3 Detector--Electrolytic conductivity or microcoulometric
detector. These types of detectors have proven effective in the analysis
of wastewaters for the parameters listed in the scope (Section 1.1). The
electrolytic conductivity detector was used to develop the method
performance statements in Section 12. Guidelines for the use of
alternate detectors are provided in Section 10.1.
5.4 Syringes--5-mL glass hypodermic with Luerlok tip (two each), if
applicable to the purging device.
5.5 Micro syringes--25-[micro]L, 0.006 in. ID needle.
5.6 Syringe valve--2-way, with Luer ends (three each).
5.7 Syringe--5-mL, gas-tight with shut-off valve.
5.8 Bottle--15-mL, screw-cap, with Teflon cap liner.
5.9 Balance--Analytical, capable of accurately weighing 0.0001 g.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.1.1 Reagent water can be generated by passing tap water through a
carbon filter bed containing about 1 lb of activated carbon (Filtrasorb-
300, Calgon Corp., or equivalent).
6.1.2 A water purification system (Millipore Super-Q or equivalent)
may be used to generate reagent water.
6.1.3 Reagent water may also be prepared by boiling water for 15
min. Subsequently, while maintaining the temperature at 90 [deg]C,
bubble a contaminant-free inert gas through the water for 1 h. While
still hot, transfer the water to a narrow mouth screw-cap bottle and
seal with a Teflon-lined septum and cap.
6.2 Sodium thiosulfate--(ACS) Granular.
6.3 Trap Materials:
6.3.1 Coconut charcoal--6/10 mesh sieved to 26 mesh, Barnabey
Cheney, CA-580-26 lot M-2649 or equivalent.
6.3.2 2,6-Diphenylene oxide polymer--Tenax, (60/80 mesh),
chromatographic grade or equivalent.
6.3.3 Methyl silicone packing--3% OV-1 on Chromosorb-W (60/80 mesh)
or equivalent.
6.3.4 Silica gel--35/60 mesh, Davison, grade-15 or equivalent.
6.4 Methanol--Pesticide quality or equivalent.
6.5 Stock standard solutions--Stock standard solutions may be
prepared from pure standard materials or purchased as certified
solutions. Prepare stock standard solutions in methanol using assayed
liquids or gases as appropriate. Because of the toxicity of some of the
organohalides, primary dilutions of these materials should be prepared
in a hood. A NIOSH/MESA approved toxic gas respirator should be used
when the analyst handles high concentrations of such materials.
6.5.1 Place about 9.8 mL of methanol into a 10-mL ground glass
stoppered volumetric flask. Allow the flask to stand, unstoppered, for
about 10 min or until all alcohol wetted surfaces have dried. Weigh the
flask to the learest 0.1 mg.
6.5.2 Add the assayed reference material:
6.5.2.1 Liquid--Using a 100 [micro]L syringe, immediately add two or
more drops of assayed reference material to the flask, then reweigh. Be
sure that the drops fall directly into the alcohol without contacting
the neck of the flask.
[[Page 79]]
6.5.2.2 Gases--To prepare standards for any of the six halocarbons
that boil below 30 [deg]C (bromomethane, chloroethane, chloromethane,
dichlorodifluoromethane, trichlorofluoromethane, vinyl chloride), fill a
5-mL valved gas-tight syringe with the reference standard to the 5.0-mL
mark. Lower the needle to 5 mm above the methanol meniscus. Slowly
introduce the reference standard above the surface of the liquid (the
heavy gas will rapidly dissolve into the methanol).
6.5.3 Reweigh, dilute to volume, stopper, then mix by inverting the
flask several times. Calculate the concentration in [micro]g/[micro]L
from the net gain in weight. When compound purity is assayed to be 96%
or greater, the weight can be used without correction to calculate the
concentration of the stock standard. Commercially prepared stock
standards can be used at any concentration if they are certified by the
malufacturer or by an independent source.
6.5.4 Transfer the stock standard solution into a Teflon-sealed
screw-cap bottle. Store, with minimal headspace, at -10 to -20 [deg]C
and protect from light.
6.5.5 Prepare fresh standards weekly for the six gases and 2-
chloroethylvinyl ether. All other standards must be replaced after one
month, or sooner if comparison with check standards indicates a problem.
6.6 Secondary dilution standards--Using stock standard solutions,
prepare secondary dilution standards in methanol that contain the
compounds of interest, either singly or mixed together. The secondary
dilution standards should be prepared at concentrations such that the
aqueous calibration standards prepared in Section 7.3.1 or 7.4.1 will
bracket the working range of the analytical system. Secondary dilution
standards should be stored with minimal headspace and should be checked
frequently for signs of degradation or evaporation, especially just
prior to preparing calibration standards from them.
6.7 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Assemble a purge and trap system that meets the specifications
in Section 5.2. Condition the trap overnight at 180 [deg]C by
backflushing with an inert gas flow of at least 20 mL/min. Condition the
trap for 10 min once daily prior to use.
7.2 Connect the purge and trap system to a gas chromatograph. The
gas chromatograph must be operated using temperature and flow rate
conditions equivalent to those given in Table 1. Calibrate the purge and
trap-gas chromatographic system using either the external standard
technique (Section 7.3) or the internal standard technique (Section
7.4).
7.3 External standard calibration procedure:
7.3.1 Prepare calibration standards at a miminum of three
concentration levels for each parameter by carefully adding 20.0
[micro]L of one or more secondary dilution standards to 100, 500, or
1000 [micro]L of reagent water. A 25-[micro]L syringe with a 0.006 in.
ID needle should be used for this operation. One of the external
standards should be at a concentration near, but above, the MDL (Table
1) and the other concentrations should correspond to the expected range
of concentrations found in real samples or should define the working
range of the detector. These aqueous standards can be stored up to 24 h,
if held in sealed vials with zero headspace as described in Section 9.2.
If not so stored, they must be discarded after 1 h.
7.3.2 Analyze each calibration standard according to Section 10, and
tabulate peak height or area responses versus the concentration in the
standard. The results can be used to prepare a calibration curve for
each compound. Alternatively, if the ratio of response to concentration
(calibration factor) is a constant over the working range (<10% relative
standard deviation, RSD), linearity through the origin can be assumed
and the average ratio or calibration factor can be used in place of a
calibration curve.
7.4 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the compounds of interest. The analyst must
further demonstrate that the measurement of the internal standard is not
affected by method or matrix interferences. Because of these
limitations, no internal standard can be suggested that is applicable to
all samples. The compounds recommended for use as surrogate spikes in
Section 8.7 have been used successfully as internal standards, because
of their generally unique retention times.
7.4.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest as described in
Section 7.3.1.
7.4.2 Prepare a spiking solution containing each of the internal
standards using the procedures described in Sections 6.5 and 6.6. It is
recommended that the secondary dilution standard be prepared at a
concentration of 15 [micro]g/mL of each internal standard compound. The
addition of 10 [micro]L of this standard to 5.0 mL of sample or
calibration standard would be equivalent to 30 [micro]g/L.
7.4.3 Analyze each calibration standard according to Section 10,
adding 10 [micro]L of internal standard spiking solution directly to the
syringe (Section 10.4). Tabulate peak height or area responses against
concentration for each compound and internal standard, and calculate
response factors (RF) for each compound using Equation 1.
[[Page 80]]
[GRAPHIC] [TIFF OMITTED] TC15NO91.094
Equation 1
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Cis = Concentration of the internal standard.
Cs = Concentration of the parameter to be measured.
If the RF value over the working range is a constant (<10% RSD), the RF
can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.5 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of a QC check sample.
7.5.1 Prepare the QC check sample as described in Section 8.2.2.
7.5.2 Analyze the QC check sample according to Section 10.
7.5.3 For each parameter, compare the response (Q) with the
corresponding calibration acceptance criteria found in Table 2. If the
responses for all parameters of interest fall within the designated
ranges, analysis of actual samples can begin. If any individual Q falls
outside the range, proceed according to Section 7.5.4.
Note: The large number of parameters in Table 2 present a
substantial probability that one or more will not meet the calibration
acceptance criteria when all parameters are analyzed.
7.5.4 Repeat the test only for those parameters that failed to meet
the calibration acceptance criteria. If the response for a parameter
does not fall within the range in this second test, a new calibration
curve, calibration factor, or RF must be prepared for that parameter
according to Section 7.3 or 7.4.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Section 10.1) to improve the separations or lower the cost of
measurements. Each time such a modification is made to the method, the
analyst is required to repeat the procedure in Section 8.2.
8.1.3 Each day, the analyst must analyze a reagent water blank to
demonstrate that interferences from the analytical system are under
control.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing each parameter of interest at a concentration of 10 [micro]g/
mL in methanol. The QC check sample concentrate must be obtained from
the U.S. Environmental Protection Agency, Environmental Monitoring and
Support Laboratory in Cincinnati, Ohio, if available. If not available
from that source, the QC check sample concentrate must be obtained from
another external source. If not available from either source above, the
QC check sample concentrate must be prepared by the laboratory using
stock standards prepared independently from those used for calibration.
8.2.2 Prepare a QC check sample to contain 20 [micro]g/L of each
parameter by adding 200 [micro]L of QC check sample concentrate to 100
mL of reagent water.
8.2.3 Analyze four 5-mL aliquots of the well-mixed QC check sample
according to Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
of interest using the four results.
[[Page 81]]
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 2. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If any individual s exceeds the precision limit or
any individual X falls outside the range for accuracy, then the system
performance is unacceptable for that parameter.
Note: The large number of parameters in Table 2 present a
substantial probability that one or more will fail at least one of the
acceptance criteria when all parameters are analyzed.
8.2.6 When one or more of the parameters tested fail at least one of
the acceptance criteria, the analyst must proceed according to Section
8.2.6.1 or 8.2.6.2.
8.2.6.1 Locate and correct the source of the problem and repeat the
test for all parameters of interest beginning with Section 8.2.3.
8.2.6.2 Beginning with Section 8.2.3, repeat the test only for those
parameters that failed to meet criteria. Repeated failure, however, will
confirm a general problem with the measurement system. If this occurs,
locate and correct the source of the problem and repeat the test for all
compounds of interest beginning with Section 8.2.3.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at 20 [micro]g/L or 1 to 5 times higher than the
background concentration determined in Section 8.3.2, whichever
concentration would be larger.
8.3.2 Analyze one 5-mL sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second 5-mL sample aliquot with 10
[micro]L of the QC check sample concentrate and analyze it to determine
the concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100(A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 2. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\7\ If spiking was performed at a concentration lower than 20 [micro]g/
L, the analyst must use either the QC acceptance criteria in Table 2, or
optional QC acceptance criteria calculated for the specific spike
concentration. To calculate optional acceptance criteria for the
recovery of a parameter: (1) Calculate accuracy (X') using the equation
in Table 3, substituting the spike concentration (T) for C; (2)
calculate overall precision (S') using the equation in Table 3,
substituting X' for X; (3) calculate the range for recovery at the spike
concentration as (100 X'/T)2.44(100 S'/T)%. \7\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory. If the entire list of parameters in Table 2 must be measured
in the sample in Section 8.3, the probability that the analysis of a QC
check standard will be required is high. In this case the QC check
standard should be routinely analyzed with the spiked sample.
8.4.1 Prepare the QC check standard by adding 10 [micro]L of QC
check sample concentrate (Section 8.2.1 or 8.3.2) to 5 mL of reagent
water. The QC check standard needs only to contain the parameters that
failed criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
2. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the
[[Page 82]]
unspiked sample is suspect and may not be reported for regulatory
compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2sp to P + 2sp.
If p = 90% and sp = 10%, for example, the accuracy interval
is expressed as 70-110%. Update the accuracy assessment for each
parameter on a regular basis (e.g. after each five to ten new accuracy
measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as gas chromatography with a dissimilar column, specific element
detector, or mass spectrometer must be used. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevant performance evaluation studies.
8.7 The analyst should monitor both the performance of the
analytical system and the effectiveness of the method in dealing with
each sample matrix by spiking each sample, standard, and reagent water
blank with surrogate halocarbons. A combination of bromochloromethane,
2-bromo-1-chloropropane, and 1,4-dichlorobutane is recommended to
encompass the range of the temperature program used in this method. From
stock standard solutions prepared as in Section 6.5, add a volume to
give 750 [micro]g of each surrogate to 45 mL of reagent water contained
in a 50-mL volumetric flask, mix and dilute to volume for a
concentration of 15 ng/[micro]L. Add 10 [micro]L of this surrogate
spiking solution directly into the 5-mL syringe with every sample and
reference standard analyzed. Prepare a fresh surrogate spiking solution
on a weekly basis. If the internal standard calibration procedure is
being used, the surrogate compounds may be added directly to the
internal standard spiking solution (Section 7.4.2).
9. Sample Collection, Preservation, and Handling
9.1 All samples must be iced or refrigerated from the time of
collection until analysis. If the sample contains free or combined
chlorine, add sodium thiosulfate preservative (10 mg/40 mL is sufficient
for up to 5 ppm Cl2) to the empty sample bottle just prior to
shipping to the sampling site. EPA Methods 330.4 and 330.5 may be used
for measurement of residual chlorine. \8\ Field test kits are available
for this purpose.
9.2 Grab samples must be collected in glass containers having a
total volume of at least 25 mL. Fill the sample bottle just to
overflowing in such a manner that no air bubbles pass through the sample
as the bottle is being filled. Seal the bottle so that no air bubbles
are entrapped in it. If preservative has been added, shake vigorously
for 1 min. Maintain the hermetic seal on the sample bottle until time of
analysis.
9.3 All samples must be analyzed within 14 days of collection. \3\
10. Procedure
10.1 Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are estimated retention times
and MDL that can be achieved under these conditions. An example of the
separations achieved by Column 1 is shown in Figure 5. Other packed
columns, chromatographic conditions, or detectors may be used if the
requirements of Section 8.2 are met.
10.2 Calibrate the system daily as described in Section 7.
10.3 Adjust the purge gas (nitrogen or helium) flow rate to 40 mL/
min. Attach the trap inlet to the purging device, and set the purge and
trap system to purge (Figure 3). Open the syringe valve located on the
purging device sample introduction needle.
10.4 Allow the sample to come to ambient temperature prior to
introducing it to the syringe. Remove the plunger from a 5-mL syringe
and attach a closed syringe valve. Open the sample bottle (or standard)
and carefully pour the sample into the syringe barrel to just short of
overflowing. Replace the syringe plunger and compress the sample. Open
the syringe valve and vent any residual air while adjusting the sample
volume to 5.0 mL. Since this process of taking an aliquot destroys the
validity of the sample for future analysis, the analyst should fill a
second syringe at this time to protect against possible loss of data.
Add 10.0 [micro]L of the surrogate spiking solution (Section 8.7) and
10.0 [micro]L of the internal standard spiking solution (Section 7.4.2),
if applicable, through the valve bore, then close the valve.
10.5 Attach the syringe-syringe valve assembly to the syringe valve
on the purging device. Open the syringe valves and inject the sample
into the purging chamber.
10.6 Close both valves and purge the sample for 11.0 0.1 min at ambient temperature.
10.7 After the 11-min purge time, attach the trap to the
chromatograph, adjust the purge and trap system to the desorb mode
(Figure 4), and begin to temperature program the gas chromatograph.
Introduce the trapped materials to the GC column by rapidly heating the
trap to 180 [deg]C while
[[Page 83]]
backflushing the trap with an inert gas between 20 and 60 mL/min for 4
min. If rapid heating of the trap cannot be achieved, the GC column must
be used as a secondary trap by cooling it to 30 [deg]C (subambient
temperature, if poor peak geometry or random retention time problems
persist) instead of the initial program temperature of 45 [deg]C
10.8 While the trap is being desorbed into the gas chromatograph,
empty the purging chamber using the sample introduction syringe. Wash
the chamber with two 5-mL flushes of reagent water.
10.9 After desorbing the sample for 4 min, recondition the trap by
returning the purge and trap system to the purge mode. Wait 15 s then
close the syringe valve on the purging device to begin gas flow through
the trap. The trap temperature should be maintained at 180 [deg]C After
approximately 7 min, turn off the trap heater and open the syringe valve
to stop the gas flow through the trap. When the trap is cool, the next
sample can be analyzed.
10.10 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
10.11 If the response for a peak exceeds the working range of the
system, prepare a dilution of the sample with reagent water from the
aliquot in the second syringe and reanalyze.
11. Calculations
11.1 Determine the concentration of individual compounds in the
sample.
11.1.1 If the external standard calibration procedure is used,
calculate the concentration of the parameter being measured from the
peak response using the calibration curve or calibration factor
determined in Section 7.3.2.
11.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.4.3 and Equation 2.
Equation 2
[GRAPHIC] [TIFF OMITTED] TC15NO91.095
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Cis = Concentration of the internal standard.
11.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
12. Method Performance
12.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentration
listed in Table 1 were obtained using reagent water. \11\. Similar
results were achieved using representative wastewaters. The MDL actually
achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
12.2 This method is recommended for use in the concentration range
from the MDL to 1000 x MDL. Direct aqueous injection techniques should
be used to measure concentration levels above 1000 x MDL.
12.3 This method was tested by 20 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
at six concentrations over the range 8.0 to 500 [micro]g/L. \9\ Single
operator precision, overall precision, and method accuracy were found to
be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 3.
References
1. 40 CFR part 136, appendix B.
2. Bellar, T.A., and Lichtenberg, J.J. ``Determining Volatile
Organics at Microgram-per-Litre-Levels by Gas Chromatography,'' Journal
of the American Water Works Association, 66, 739 (1974).
3. Bellar, T.A., and Lichtenberg, J.J. ``Semi-Automated Headspace
Analysis of Drinking Waters and Industrial Waters for Purgeable Volatile
Organic Compounds,'' Proceedings from Symposium on Measurement of
Organic Pollutants in Water and Wastewater, American Society for Testing
and Materials, STP 686, C.E. Van Hall, editor, 1978.
4. ``Carcinogens--Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
5. ``OSHA Safety and Health Standards, General Industry'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
[[Page 84]]
6. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value 1.22
derived in this report.)
8. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for
Chemical Analysis of Water and Wastes, EPA 600/4-79-020, U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268, March 1979.
9. ``EPA Method Study 24, Method 601--Purgeable Halocarbons by the
Purge and Trap Method,'' EPA 600/4-84-064, National Technical
Information Service, PB84-212448, Springfield, Virginia 22161, July
1984.
10. ``Method Validation Data for EPA Method 601,'' Memorandum from
B. Potter, U.S. Environmental Protection Agency, Environmental
Monitoring and Support Laboratory, Cincinnati, Ohio 45268, November 10,
1983.
11. Bellar, T. A., Unpublished data, U.S. Environmental Protection
Agency, Environmental Monitoring and Support Laboratory, Cincinnati,
Ohio 45268, 1981.
Table 1--Chromatographic Conditions and Method Detection Limits
----------------------------------------------------------------------------------------------------------------
Retention time (min) Method detection
Parameter ------------------------------------ limit ([micro]g/
Column 1 Column 2 L)
----------------------------------------------------------------------------------------------------------------
Chloromethane............................................. 1.50 5.28 0.08
Bromomethane.............................................. 2.17 7.05 1.18
Dichlorodifluoromethane................................... 2.62 nd 1.81
Vinyl chloride............................................ 2.67 5.28 0.18
Chloroethane.............................................. 3.33 8.68 0.52
Methylene chloride........................................ 5.25 10.1 0.25
Trichlorofluoromethane.................................... 7.18 nd nd
1,1-Dichloroethene........................................ 7.93 7.72 0.13
1,1-Dichloroethane........................................ 9.30 12.6 0.07
trans-1,2-Dichloroethene.................................. 10.1 9.38 0.10
Chloroform................................................ 10.7 12.1 0.05
1,2-Dichloroethane........................................ 11.4 15.4 0.03
1,1,1-Trichloroethane..................................... 12.6 13.1 0.03
Carbon tetrachloride...................................... 13.0 14.4 0.12
Bromodichloromethane...................................... 13.7 14.6 0.10
1,2-Dichloropropane....................................... 14.9 16.6 0.04
cis-1,3-Dichloropropene................................... 15.2 16.6 0.34
Trichloroethene........................................... 15.8 13.1 0.12
Dibromochloromethane...................................... 16.5 16.6 0.09
1,1,2-Trichloroethane..................................... 16.5 18.1 0.02
trans-1,3-Dichloropropene................................. 16.5 18.0 0.20
2-Chloroethylvinyl ether.................................. 18.0 nd 0.13
Bromoform................................................. 19.2 19.2 0.20
1,1,2,2-Tetrachloroethane................................. 21.6 nd 0.03
Tetrachloroethene......................................... 21.7 15.0 0.03
Chlorobenzene............................................. 24.2 18.8 0.25
1,3-Dichlorobenzene....................................... 34.0 22.4 0.32
1,2-Dichlorobenzene....................................... 34.9 23.5 0.15
1,4-Dichlorobenzene....................................... 35.4 22.3 0.24
----------------------------------------------------------------------------------------------------------------
Column 1 conditions: Carbopack B (60/80 mesh) coated with 1% SP-1000 packed in an 8 ft x 0.1 in. ID stainless
steel or glass column with helium carrier gas at 40 mL/min flow rate. Column temperature held at 45 [deg]C for
3 min then programmed at 8 [deg]C/min to 220 [deg]C and held for 15 min.
Column 2 conditions: Porisil-C (100/120 mesh) coated with n-octane packed in a 6 ft x 0.1 in. ID stainless steel
or glass column with helium carrier gas at 40 mL/min flow rate. Column temperature held at 50 [deg]C for 3 min
then programmed at 6 [deg]C/min to 170 [deg]C and held for 4 min.
nd = not determined.
Table 2--Calibration and QC Acceptance Criteria--Method 601 \a\
----------------------------------------------------------------------------------------------------------------
Limit for
Range for Q s Range for X Range P,
Parameter ([micro]g/L) ([micro]g/ ([micro]g/L) Ps (%)
L)
----------------------------------------------------------------------------------------------------------------
Bromodichloromethane.................................... 15.2-24.8 4.3 10.7-32.0 42-172
Bromoform............................................... 14.7-25.3 4.7 5.0-29.3 13-159
Bromomethane............................................ 11.7-28.3 7.6 3.4-24.5 D-144
Carbon tetrachloride.................................... 13.7-26.3 5.6 11.8-25.3 43-143
Chlorobenzene........................................... 14.4-25.6 5.0 10.2-27.4 38-150
Chloroethane............................................ 15.4-24.6 4.4 11.3-25.2 46-137
2-Chloroethylvinyl ether................................ 12.0-28.0 8.3 4.5-35.5 14-186
Chloroform.............................................. 15.0-25.0 4.5 12.4-24.0 49-133
Chloromethane........................................... 11.9-28.1 7.4 D-34.9 D-193
[[Page 85]]
Dibromochloromethane.................................... 13.1-26.9 6.3 7.9-35.1 24-191
1,2-Dichlorobenzene..................................... 14.0-26.0 5.5 1.7-38.9 D-208
1,3-Dichlorobenzene..................................... 9.9-30.1 9.1 6.2-32.6 7-187
1,4-Dichlorobenzene..................................... 13.9-26.1 5.5 11.5-25.5 42-143
1,1-Dichloroethane...................................... 16.8-23.2 3.2 11.2-24.6 47-132
1,2-Dichloroethane...................................... 14.3-25.7 5.2 13.0-26.5 51-147
1,1-Dichloroethene...................................... 12.6-27.4 6.6 10.2-27.3 28-167
trans-1,2-Dichloroethene................................ 12.8-27.2 6.4 11.4-27.1 38-155
1,2-Dichloropropane..................................... 14.8-25.2 5.2 10.1-29.9 44-156
cis-1,3-Dichloropropene................................. 12.8-27.2 7.3 6.2-33.8 22-178
trans-1,3-Dichloropropene............................... 12.8-27.2 7.3 6.2-33.8 22-178
Methylene chloride...................................... 15.5-24.5 4.0 7.0-27.6 25-162
1,1,2,2-Tetrachloroethane............................... 9.8-30.2 9.2 6.6-31.8 8-184
Tetrachloroethene....................................... 14.0-26.0 5.4 8.1-29.6 26-162
1,1,1-Trichloroethane................................... 14.2-25.8 4.9 10.8-24.8 41-138
1,1,2-Trichloroethane................................... 15.7-24.3 3.9 9.6-25.4 39-136
Trichloroethene......................................... 15.4-24.6 4.2 9.2-26.6 35-146
Trichlorofluoromethane.................................. 13.3-26.7 6.0 7.4-28.1 21-156
Vinyl chloride.......................................... 13.7-26.3 5.7 8.2-29.9 28-163
----------------------------------------------------------------------------------------------------------------
\a\ Criteria were calculated assuming a QC check sample concentration of 20 [micro]g/L.
Q = Concentration measured in QC check sample, in [micro]g/L (Section 7.5.3).
s = Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X = Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps = Percent recovery measured (Section 8.3.2, Section 8.4.2).
D = Detected; result must be greater than zero.
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 3.
Table 3--Method Accuracy and Precision as Functions of Concentration--Method 601
----------------------------------------------------------------------------------------------------------------
Single analyst
Parameter Accuracy, as recovery, precision, sr' Overall precision, S'
X' ([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
Bromodichloromethane................ 1.12C-1.02 0.11X + 0.04 0.20X + 1.00
Bromoform........................... 0.96C-2.05 0.12X + 0.58 0.21X + 2.41
Bromomethane........................ 0.76C-1.27 0.28X + 0.27 0.36X + 0.94
Carbon tetrachloride................ 0.98C-1.04 0.15X + 0.38 0.20X + 0.39
Chlorobenzene....................... 1.00C-1.23 0.15X-0.02 0.18X + 1.21
Choroethane......................... 0.99C-1.53 0.14X-0.13 0.17X + 0.63
2-Chloroethylvinyl ether \a\........ 1.00C 0.20X 0.35X
Chloroform.......................... 0.93C-0.39 0.13X + 0.15 0.19X-0.02
Chloromethane....................... 0.77C + 0.18 0.28X-0.31 0.52X + 1.31
Dibromochloromethane................ 0.94C + 2.72 0.11X + 1.10 0.24X + 1.68
1,2-Dichlorobenzene................. 0.93C + 1.70 0.20X + 0.97 0.13X + 6.13
1,3-Dichlorobenzene................. 0.95C + 0.43 0.14X + 2.33 0.26X + 2.34
1,4-Dichlorobenzene................. 0.93C-0.09 0.15X + 0.29 0.20X + 0.41
1,1-Dichloroethane.................. 0.95C-1.08 0.09X + 0.17 0.14X + 0.94
1,2-Dichloroethane.................. 1.04C-1.06 0.11X + 0.70 0.15X + 0.94
1,1-Dichloroethene.................. 0.98C-0.87 0.21X-0.23 0.29X-0.40
trans-1,2-Dichloroethene............ 0.97C-0.16 0.11X + 1.46 0.17X + 1.46
1,2-Dichloropropane \a\............. 1.00C 0.13X 0.23X
cis-1,3-Dichloropropene \a\......... 1.00C 0.18X 0.32X
trans-1,3-Dichloropropene \a\....... 1.00C 0.18X 0.32X
Methylene chloride.................. 0.91C-0.93 0.11X + 0.33 0.21X + 1.43
1,1,2,2-Tetrachloroethene........... 0.95C + 0.19 0.14X + 2.41 0.23X + 2.79
Tetrachloroethene................... 0.94C + 0.06 0.14X + 0.38 0.18X + 2.21
1,1,1-Trichloroethane............... 0.90C-0.16 0.15X + 0.04 0.20X + 0.37
1,1,2-Trichloroethane............... 0.86C + 0.30 0.13X-0.14 0.19X + 0.67
Trichloroethene..................... 0.87C + 0.48 0.13X-0.03 0.23X + 0.30
Trichlorofluoromethane.............. 0.89C-0.07 0.15X + 0.67 0.26X + 0.91
Vinyl chloride...................... 0.97C-0.36 0.13X + 0.65 0.27X + 0.40
----------------------------------------------------------------------------------------------------------------
X' = Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/L.
sn' = Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S\1\ = Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C = True value for the concentration, in [micro]g/L.
X = Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
\a\ Estimates based upon the performance in a single laboratory. \10\
[[Page 86]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.000
[[Page 87]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.001
[[Page 88]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.002
[[Page 89]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.003
[[Page 90]]
Method 602--Purgeable Aromatics
1. Scope and Application
1.1 This method covers the determination of various purgeable
aromatics. The following parameters may be determined by this method:
------------------------------------------------------------------------
STORET
Parameter No. CAS No.
------------------------------------------------------------------------
Benzene.......................................... 34030 71-43-2
Chlorobenzene.................................... 34301 108-90-7
1,2-Dichlorobenzene.............................. 34536 95-50-1
1,3-Dichlorobenzene.............................. 34566 541-73-1
1,4-Dichlorobenzene.............................. 34571 106-46-7
Ethylbenzene..................................... 34371 100-41-4
Toluene.......................................... 34010 108-88-3
------------------------------------------------------------------------
1.2 This is a purge and trap gas chromatographic (GC) method
applicable to the determination of the compounds listed above in
municipal and industrial discharges as provided under 40 CFR 136.1. When
this method is used to analyze unfamiliar samples for any or all of the
compounds above, compound identifications should be supported by at
least one additional qualitative technique. This method describes
analytical conditions for a second gas chromatographic column that can
be used to confirm measurements made with the primary column. Method 624
provides gas chromatograph/mass spectrometer (GC/MS) conditions
appropriate for the qualitative and quantitative confirmation of results
for all of the parameters listed above.
1.3 The method detection limit (MDL, defined in Section 12.1) \1\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
1.4 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.5 This method is restricted to use by or under the supervision of
analysts experienced in the operation of a purge and trap system and a
gas chromatograph and in the interpretation of gas chromatograms. Each
analyst must demonstrate the ability to generate acceptable results with
this method using the procedure described in Section 8.2.
2. Summary of Method
2.1 An inert gas is bubbled through a 5-mL water sample contained in
a specially-designed purging chamber at ambient temperature. The
aromatics are efficiently transferred from the aqueous phase to the
vapor phase. The vapor is swept through a sorbent trap where the
aromatics are trapped. After purging is completed, the trap is heated
and backflushed with the inert gas to desorb the aromatics onto a gas
chromatographic column. The gas chromatograph is temperature programmed
to separate the aromatics which are then detected with a photoionization
detector. \2 3\
2.2 The method provides an optional gas chromatographic column that
may be helpful in resolving the compounds of interest from interferences
that may occur.
3. Interferences
3.1 Impurities in the purge gas and organic compounds outgassing
from the plumbing ahead of the trap account for the majority of
contamination problems. The analytical system must be demonstrated to be
free from contamination under the conditions of the analysis by running
laboratory reagent blanks as described in Section 8.1.3. The use of non-
Teflon plastic tubing, non-Teflon thread sealants, or flow controllers
with rubber components in the purge and trap system should be avoided.
3.2 Samples can be contaminated by diffusion of volatile organics
through the septum seal into the sample during shipment and storage. A
field reagent blank prepared from reagent water and carried through the
sampling and handling protocol can serve as a check on such
contamination.
3.3 Contamination by carry-over can occur whenever high level and
low level samples are sequentially analyzed. To reduce carry-over, the
purging device and sample syringe must be rinsed with reagent water
between sample analyses. Whenever an unusually concentrated sample is
encountered, it should be followed by an analysis of reagent water to
check for cross contamination. For samples containing large amounts of
water-soluble materials, suspended solids, high boiling compounds or
high aromatic levels, it may be necessary to wash the purging device
with a detergent solution, rinse it with distilled water, and then dry
it in an oven at 105 [deg]C between analyses. The trap and other parts
of the system are also subject to contamination; therefore, frequent
bakeout and purging of the entire system may be required.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety
[[Page 91]]
are available and have been identified 4 6 for the
information of the analyst.
4.2 The following parameters covered by this method have been
tentatively classified as known or suspected, human or mammalian
carcinogens: benzene and 1,4-dichlorobenzene. Primary standards of these
toxic compounds should be prepared in a hood. A NIOSH/MESA approved
toxic gas respirator should be worn when the analyst handles high
concentrations of these toxic compounds.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete sampling.
5.1.1 Vial]25-mL capacity or larger, equipped with a screw cap with
a hole in the center (Pierce 13075 or equivalent). Detergent wash,
rinse with tap and distilled water, and dry at 105 [deg]C before use.
5.1.2 Septum--Teflon-faced silicone (Pierce 12722 or equivalent).
Detergent wash, rinse with tap and distilled water, and dry at 105
[deg]C for 1 h before use.
5.2 Purge and trap system--The purge and trap system consists of
three separate pieces of equipment: A purging device, trap, and
desorber. Several complete systems are now commercially available.
5.2.1 The purging device must be designed to accept 5-mL samples
with a water column at least 3 cm deep. The gaseous head space between
the water column and the trap must have a total volume of less than 15
mL. The purge gas must pass through the water column as finely divided
bubbles with a diameter of less than 3 mm at the origin. The purge gas
must be introduced no more than 5 mm from the base of the water column.
The purging device illustrated in Figure 1 meets these design criteria.
5.2.2 The trap must be at least 25 cm long and have an inside
diameter of at least 0.105 in.
5.2.2.1 The trap is packed with 1 cm of methyl silicone coated
packing (Section 6.4.2) and 23 cm of 2,6-diphenylene oxide polymer
(Section 6.4.1) as shown in Figure 2. This trap was used to develop the
method performance statements in Section 12.
5.2.2.2 Alternatively, either of the two traps described in Method
601 may be used, although water vapor will preclude the measurement of
low concentrations of benzene.
5.2.3 The desorber must be capable of rapidly heating the trap to
180 [deg]C. The polymer section of the trap should not be heated higher
than 180 [deg]C and the remaining sections should not exceed 200 [deg]C.
The desorber illustrated in Figure 2 meets these design criteria.
5.2.4 The purge and trap system may be assembled as a separate unit
or be coupled to a gas chromatograph as illustrated in Figures 3, 4, and
5.
5.3 Gas chromatograph--An analytical system complete with a
temperature programmable gas chromatograph suitable for on-column
injection and all required accessories including syringes, analytical
columns, gases, detector, and strip-chart recorder. A data system is
recommended for measuring peak areas.
5.3.1 Column 1--6 ft long x 0.082 in. ID stainless steel or glass,
packed with 5% SP-1200 and 1.75% Bentone-34 on Supelcoport (100/120
mesh) or equivalent. This column was used to develop the method
performance statements in Section 12. Guidelines for the use of
alternate column packings are provided in Section 10.1.
5.3.2 Column 2--8 ft long x 0.1 in ID stainless steel or glass,
packed with 5% 1,2,3-Tris(2-cyanoethoxy)propane on Chromosorb W-AW (60/
80 mesh) or equivalent.
5.3.3 Detector--Photoionization detector (h-Nu Systems, Inc. Model
PI-51-02 or equivalent). This type of detector has been proven effective
in the analysis of wastewaters for the parameters listed in the scope
(Section 1.1), and was used to develop the method performance statements
in Section 12. Guidelines for the use of alternate detectors are
provided in Section 10.1.
5.4 Syringes--5-mL glass hypodermic with Luerlok tip (two each), if
applicable to the purging device.
5.5 Micro syringes--25-[micro]L, 0.006 in. ID needle.
5.6 Syringe valve--2-way, with Luer ends (three each).
5.7 Bottle--15-mL, screw-cap, with Teflon cap liner.
5.8 Balance--Analytical, capable of accurately weighing 0.0001 g.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.1.1 Reagent water can be generated by passing tap water through a
carbon filter bed containing about 1 lb of activated carbon (Filtrasorb-
300, Calgon Corp., or equivalent).
6.1.2 A water purification system (Millipore Super-Q or equivalent)
may be used to generate reagent water.
6.1.3 Reagent water may also be prepared by boiling water for 15
min. Subsequently, while maintaining the temperature at 90 [deg]C,
bubble a contaminant-free inert gas through the water for 1 h. While
still hot, transfer the water to a narrow mouth screw-cap bottle and
seal with a Teflon-lined septum and cap.
6.2 Sodium thiosulfate--(ACS) Granular.
6.3 Hydrochloric acid (1 + 1)--Add 50 mL of concentrated HCl (ACS)
to 50 mL of reagent water.
6.4 Trap Materials:
[[Page 92]]
6.4.1 2,6-Diphenylene oxide polymer--Tenax, (60/80 mesh),
chromatographic grade or equivalent.
6.4.2 Methyl silicone packing--3% OV-1 on Chromosorb-W (60/80 mesh)
or equivalent.
6.5 Methanol--Pesticide quality or equivalent.
6.6 Stock standard solutions--Stock standard solutions may be
prepared from pure standard materials or purchased as certified
solutions. Prepare stock standard solutions in methanol using assayed
liquids. Because of the toxicity of benzene and 1,4-dichlorobenzene,
primary dilutions of these materials should be prepared in a hood. A
NIOSH/MESA approved toxic gas respirator should be used when the analyst
handles high concentrations of such materials.
6.6.1 Place about 9.8 mL of methanol into a 10-mL ground glass
stoppered volumetric flask. Allow the flask to stand, unstoppered, for
about 10 min or until all alcohol wetted surfaces have dried. Weigh the
flask to the nearest 0.1 mg.
6.6.2 Using a 100-[micro]L syringe, immediately add two or more
drops of assayed reference material to the flask, then reweigh. Be sure
that the drops fall directly into the alcohol without contacting the
neck of the flask.
6.6.3 Reweigh, dilute to volume, stopper, then mix by inverting the
flask several times. Calculate the concentration in [micro]g/[micro]L
from the net gain in weight. When compound purity is assayed to be 96%
or greater, the weight can be used without correction to calculate the
concentration of the stock standard. Commercially prepared stock
standards can be used at any concentration if they are certified by the
manufacturer or by an independent source.
6.6.4 Transfer the stock standard solution into a Teflon-sealed
screw-cap bottle. Store at 4 [deg]C and protect from light.
6.6.5 All standards must be replaced after one month, or sooner if
comparison with check standards indicates a problem.
6.7 Secondary dilution standards--Using stock standard solutions,
prepare secondary dilution standards in methanol that contain the
compounds of interest, either singly or mixed together. The secondary
dilution standards should be prepared at concentrations such that the
aqueous calibration standards prepared in Section 7.3.1 or 7.4.1 will
bracket the working range of the analytical system. Secondary solution
standards must be stored with zero headspace and should be checked
frequently for signs of degradation or evaporation, especially just
prior to preparing calibration standards from them.
6.8 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Assemble a purge and trap system that meets the specifications
in Section 5.2. Condition the trap overnight at 180 [deg]C by
backflushing with an inert gas flow of at least 20 mL/min. Condition the
trap for 10 min once daily prior to use.
7.2 Connect the purge and trap system to a gas chromatograph. The
gas chromatograph must be operated using temperature and flow rate
conditions equivalent to those given in Table 1. Calibrate the purge and
trap-gas chromatographic system using either the external standard
technique (Section 7.3) or the internal standard technique (Section
7.4).
7.3 External standard calibration procedure:
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter by carefully adding 20.0
[micro]L of one or more secondary dilution standards to 100, 500, or
1000 mL of reagent water. A 25-[micro]L syringe with a 0.006 in. ID
needle should be used for this operation. One of the external standards
should be at a concentration near, but above, the MDL (Table 1) and the
other concentrations should correspond to the expected range of
concentrations found in real samples or should define the working range
of the detector. These aqueous standards must be prepared fresh daily.
7.3.2 Analyze each calibration standard according to Section 10, and
tabulate peak height or area responses versus the concentration in the
standard. The results can be used to prepare a calibration curve for
each compound. Alternatively, if the ratio of response to concentration
(calibration factor) is a constant over the working range (<10% relative
standard deviation, RSD), linearity through the origin can be assumed
and the average ratio or calibration factor can be used in place of a
calibration curve.
7.4 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the compounds of interest. The analyst must
further demonstrate that the measurement of the internal standard is not
affected by method or matrix interferences. Because of these
limitations, no internal standard can be suggested that is applicable to
all samples. The compound, [alpha],[alpha],[alpha],-trifluorotoluene,
recommended as a surrogate spiking compound in Section 8.7 has been used
successfully as an internal standard.
7.4.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest as described in
Section 7.3.1.
7.4.2 Prepare a spiking solution containing each of the internal
standards using the procedures described in Sections 6.6 and 6.7. It is
recommended that the secondary dilution standard be prepared at a
concentration of 15 [micro]g/mL of each internal standard compound. The
addition of 10 [micro]l of this
[[Page 93]]
standard to 5.0 mL of sample or calibration standard would be equivalent
to 30 [micro]g/L.
7.4.3 Analyze each calibration standard according to Section 10,
adding 10 [micro]L of internal standard spiking solution directly to the
syringe (Section 10.4). Tabulate peak height or area responses against
concentration for each compound and internal standard, and calculate
response factors (RF) for each compound using Equation 1.
RF = (As)(Cis (Ais)(Cs)
Equation 1
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Cis = Concentration of the internal standard
Cs = Concentration of the parameter to be measured.
If the RF value over the working range is a constant (<10% RSD), the RF
can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.5 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of a QC check sample.
7.5.1 Prepare the QC check sample as described in Section 8.2.2.
7.5.2 Analyze the QC check sample according to Section 10.
7.5.3 For each parameter, compare the response (Q) with the
corresponding calibration acceptance criteria found in Table 2. If the
responses for all parameters of interest fall within the designated
ranges, analysis of actual samples can begin. If any individual Q falls
outside the range, a new calibration curve, calibration factor, or RF
must be prepared for that parameter according to Section 7.3 or 7.4.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Section 10.1) to improve the separations or lower the cost of
measurements. Each time such a modification is made to the method, the
analyst is required to repeat the procedure in Section 8.2.
8.1.3 Each day, the analyst must analyze a reagent water blank to
demonstrate that interferences from the analytical system are under
control.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing each parameter of interest at a concentration of 10 [micro]g/
mL in methanol. The QC check sample concentrate must be obtained from
the U.S. Environmental Protection Agency, Environmental Monitoring and
Support Laboratory in Cincinnati, Ohio, if available. If not available
from that source, the QC check sample concentrate must be obtained from
another external source. If not available from either source above, the
QC check sample concentrate must be prepared by the laboratory using
stock standards prepared independently from those used for calibration.
8.2.2 Prepare a QC check sample to contain 20 [micro]g/L of each
parameter by adding 200 [micro]L of QC check sample concentrate to 100
mL of reagant water.
8.2.3 Analyze four 5-mL aliquots of the well-mixed QC check sample
according to Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
of interest using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively,
[[Page 94]]
found in Table 2. If s and X for all parameters of interest meet the
acceptance criteria, the system performance is acceptable and analysis
of actual samples can begin. If any individual s exceeds the precision
limit or any individual X falls outside the range for accuracy, the
system performance is unacceptable for that parameter.
Note: The large number of parameters in Table 2 present a
substantial probability that one or more will fail at least one of the
acceptance criteria when all parameters are analyzed.
8.2.6 When one or more of the parameters tested fail at least one of
the acceptance criteria, the analyst must proceed according to Section
8.2.6.1 or 8.2.6.2.
8.2.6.1 Locate and correct the source of the problem and repeat the
test for all parameters of interest beginning with Section 8.2.3.
8.2.6.2 Beginning with Section 8.2.3, repeat the test only for those
parameters that failed to meet criteria. Repeated failure, however, will
confirm a general problem with the measurement system. If this occurs,
locate and correct the source of the problem and repeat the test for all
compounds of interest beginning with Section 8.2.3.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at 20 [micro]g/L or 1 to 5 times higher than the
background concentration determined in Section 8.3.2, whichever
concentration would be larger.
8.3.2 Analyze one 5-mL sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second 5-mL sample aliquot with 10
[micro]L of the QC check sample concentrate and analyze it to determine
the concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100(A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 2. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\7\ If spiking was performed at a concentration lower than 20 [micro]g/
L, the analyst must use either the QC acceptance criteria in Table 2, or
optional QC acceptance criteria calculated for the specific spike
concentration. To calculate optional acceptance criteria for the
recovery of a parameter: (1) Calculate accuracy (X') using the equation
in Table 3, substituting the spike concentration (T) for C; (2)
calculate overall precision (S') using the equation in Table 3,
substituting X' for X; (3) calculate the range for recovery at the spike
concentration as (100 X'/T) 2.44(100 S'/T)%. \7\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory.
8.4.1 Prepare the QC check standard by adding 10 [micro]L of QC
check sample concentrate (Section 8.2.1 or 8.3.2) to 5 mL of reagent
water. The QC check standard needs only to contain the parameters that
failed criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
2. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P)
[[Page 95]]
and the standard deviation of the percent recovery (sp).
Express the accuracy assessment as a percent recovery interval from P-
2sp to P + 2sp. If P = 90% and sp =
10%, for example, the accuracy interval is expressed as 70-110%. Update
the accuracy assessment for each parameter on a regular basis (e.g.
after each five to ten new accuracy measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as gas chromatography with a dissimilar column, specific element
detector, or mass spectrometer must be used. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevant performance evaluation studies.
8.7 The analyst should monitor both the performance of the
analytical system and the effectiveness of the method in dealing with
each sample matrix by spiking each sample, standard, and reagent water
blank with surrogate compounds (e.g. [alpha], [alpha], [alpha],-
trifluorotoluene) that encompass the range of the temperature program
used in this method. From stock standard solutions prepared as in
Section 6.6, add a volume to give 750 [micro]g of each surrogate to 45
mL of reagent water contained in a 50-mL volumetric flask, mix and
dilute to volume for a concentration of 15 mg/[micro]L. Add 10 [micro]L
of this surrogate spiking solution directly into the 5-mL syringe with
every sample and reference standard analyzed. Prepare a fresh surrogate
spiking solution on a weekly basis. If the internal standard calibration
procedure is being used, the surrogate compounds may be added directly
to the internal standard spiking solution (Section 7.4.2).
9. Sample Collection, Preservation, and Handling
9.1 The samples must be iced or refrigerated from the time of
collection until analysis. If the sample contains free or combined
chlorine, add sodium thiosulfate preservative (10 mg/40 mL is sufficient
for up to 5 ppm Cl2) to the empty sample bottle just prior to
shipping to the sampling site. EPA Method 330.4 or 330.5 may be used for
measurement of residual chlorine. \8\ Field test kits are available for
this purpose.
9.2 Collect about 500 mL of sample in a clean container. Adjust the
pH of the sample to about 2 by adding 1 + 1 HCl while stirring. Fill the
sample bottle in such a manner that no air bubbles pass through the
sample as the bottle is being filled. Seal the bottle so that no air
bubbles are entrapped in it. Maintain the hermetic seal on the sample
bottle until time of analysis.
9.3 All samples must be analyzed within 14 days of collection. \3\
10. Procedure
10.1 Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are estimated retention times
and MDL that can be achieved under these conditions. An example of the
separations achieved by Column 1 is shown in Figure 6. Other packed
columns, chromatographic conditions, or detectors may be used if the
requirements of Section 8.2 are met.
10.2 Calibrate the system daily as described in Section 7.
10.3 Adjust the purge gas (nitrogen or helium) flow rate to 40 mL/
min. Attach the trap inlet to the purging device, and set the purge and
trap system to purge (Figure 3). Open the syringe valve located on the
purging device sample introduction needle.
10.4 Allow the sample to come to ambient temperature prior to
introducing it to the syringe. Remove the plunger from a 5-mL syringe
and attach a closed syringe valve. Open the sample bottle (or standard)
and carefully pour the sample into the syringe barrel to just short of
overflowing. Replace the syringe plunger and compress the sample. Open
the syringe valve and vent any residual air while adjusting the sample
volume to 5.0 mL. Since this process of taking an aliquot destroys the
validity of the sample for future analysis, the analyst should fill a
second syringe at this time to protect against possible loss of data.
Add 10.0 [micro]L of the surrogate spiking solution (Section 8.7) and
10.0 [micro]L of the internal standard spiking solution (Section 7.4.2),
if applicable, through the valve bore, then close the valve.
10.5 Attach the syringe-syringe valve assembly to the syringe valve
on the purging device. Open the syringe valves and inject the sample
into the purging chamber.
10.6 Close both valves and purge the sample for 12.0 0.1 min at ambient temperature.
10.7 After the 12-min purge time, disconnect the purging device from
the trap. Dry the trap by maintaining a flow of 40 mL/min of dry purge
gas through it for 6 min (Figure 4). If the purging device has no
provision for bypassing the purger for this step, a dry purger should be
inserted into the device to minimize moisture in the gas. Attach the
trap to the chromatograph, adjust the purge and trap system to the
desorb mode (Figure 5), and begin to temperature program the gas
chromatograph. Introduce the trapped materials to the GC column by
rapidly heating the trap to 180 [deg]C while backflushing the trap with
an inert gas between 20 and 60 mL/min for 4 min. If rapid heating of the
trap cannot be achieved, the GC column must be used as
[[Page 96]]
a secondary trap by cooling it to 30 [deg]C (subambient temperature, if
poor peak geometry and random retention time problems persist) instead
of the initial program temperature of 50 [deg]C.
10.8 While the trap is being desorbed into the gas chromatograph
column, empty the purging chamber using the sample introduction syringe.
Wash the chamber with two 5-mL flushes of reagent water.
10.9 After desorbing the sample for 4 min, recondition the trap by
returning the purge and trap system to the purge mode. Wait 15 s, then
close the syringe valve on the purging device to begin gas flow through
the trap. The trap temperature should be maintained at 180 [deg]C. After
approximately 7 min, turn off the trap heater and open the syringe valve
to stop the gas flow through the trap. When the trap is cool, the next
sample can be analyzed.
10.10 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
10.11 If the response for a peak exceeds the working range of the
system, prepare a dilution of the sample with reagent water from the
aliquot in the second syringe and reanalyze.
11. Calculations
11.1 Determine the concentration of individual compounds in the
sample.
11.1.1 If the external standard calibration procedure is used,
calculate the concentration of the parameter being measured from the
peak response using the calibration curve or calibration factor
determined in Section 7.3.2.
11.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.4.3 and Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.096
Equation 2
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Cis = Concentration of the internal standard.
11.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
12. Method Performance
12.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentrations
listed in Table 1 were obtained using reagent water. \9\ Similar results
were achieved using representative wastewaters. The MDL actually
achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
12.2 This method has been demonstrated to be applicable for the
concentration range from the MDL to 100 x MDL. \9\ Direct aqueous
injection techniques should be used to measure concentration levels
above 1000 x MDL.
12.3 This method was tested by 20 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
at six concentrations over the range 2.1 to 550 [micro]g/L. \9\ Single
operator precision, overall precision, and method accuracy were found to
be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 3.
References
1. 40 CFR part 136, appendix B.
2. Lichtenberg, J.J. ``Determining Volatile Organics at Microgram-
per-Litre-Levels by Gas Chromatography,'' Journal American Water Works
Association, 66, 739 (1974).
3. Bellar, T.A., and Lichtenberg, J.J. ``Semi-Automated Headspace
Analysis of Drinking Waters and Industrial Waters for Purgeable Volatile
Organic Compounds,'' Proceedings of Symposium on Measurement of Organic
Pollutants in Water and Wastewater. American Society for Testing and
Materials, STP 686, C.E. Van Hall, editor, 1978.
4. ``Carcinogens--Working with Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health.
Publication No. 77-206, August 1977.
5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
6. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Safety, 3rd Edition, 1979.
7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3. is two times the value 1.22
derived in this report.)
[[Page 97]]
8.``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S.
Environmental Protection Agency, Office of Research and Development,
Environmental Monitoring and Support Laboratory, Cincinnati, Ohio 45268.
March 1979.
9. ``EPA Method Study 25, Method 602, Purgeable Aromatics,'' EPA
600/4-84-042, National Technical Information Service, PB84-196682,
Springfield, Virginia 22161, May 1984.
Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
Retention time (min) Method
---------------------- detection
Parameter limit
Column 1 Column 2 ([micro]g/
L)
------------------------------------------------------------------------
Benzene............................... 3.33 2.75 0.2
Toluene............................... 5.75 4.25 0.2
Ethylbenzene.......................... 8.25 6.25 0.2
Chlorobenzene......................... 9.17 8.02 0.2
1,4-Dichlorobenzene................... 16.8 16.2 0.3
1,3-Dichlorobenzene................... 18.2 15.0 0.4
1,2-Dichlorobenzene................... 25.9 19.4 0.4
------------------------------------------------------------------------
Column 1 conditions: Supelcoport (100/120 mesh) coated with 5% SP-1200/
1.75% Bentone-34 packed in a 6 ft x 0.085 in. ID stainless steel
column with helium carrier gas at 36 mL/min flow rate. Column
temperature held at 50 [deg]C for 2 min then programmed at 6 [deg]C/
min to 90 [deg]C for a final hold.
Column 2 conditions: Chromosorb W-AW (60/80 mesh) coated with 5% 1,2,3-
Tris(2-cyanoethyoxy)propane packed in a 6 ft x 0.085 in. ID stainless
steel column with helium carrier gas at 30 mL/min flow rate. Column
temperature held at 40 [deg]C for 2 min then programmed at 2 [deg]C/
min to 100 [deg]C for a final hold.
Table 2--Calibration and QC Acceptance Criteria--Method 602 \a\
----------------------------------------------------------------------------------------------------------------
Limit for
Range for Q s Range for X Range for
Parameter ([micro]g/ ([micro]g/ ([micro]g/ P, Ps(%)
L) L) L)
----------------------------------------------------------------------------------------------------------------
Benzene........................................................ 15.4-24.6 4.1 10.0-27.9 39-150
Chlorobenzene.................................................. 16.1-23.9 3.5 12.7-25.4 55-135
1,2-Dichlorobenzene............................................ 13.6-26.4 5.8 10.6-27.6 37-154
1,3-Dichlorobenzene............................................ 14.5-25.5 5.0 12.8-25.5 50-141
1,4-Dichlorobenzene............................................ 13.9-26.1 5.5 11.6-25.5 42-143
Ethylbenzene................................................... 12.6-27.4 6.7 10.0-28.2 32-160
Toluene........................................................ 15.5-24.5 4.0 11.2-27.7 46-148
----------------------------------------------------------------------------------------------------------------
Q = Concentration measured in QC check sample, in [micro]g/L (Section 7.5.3).
s = Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X = Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
Ps, P = Percent recovery measured (Section 8.3.2, Section 8.4.2).
\a\ Criteria were calculated assuming a QC check sample concentration of 20 [micro]g/L.
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 3.
Table 3--Method Accuracy and Precision as Functions of Concentration--Method 602
----------------------------------------------------------------------------------------------------------------
Accuracy, as Single analyst Overall
Parameter recovery, X' precision, s' precision, S'
([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
Benzene......................................................... 0.92C + 0.57 0.09X + 0.59 0.21X + 0.56
Chlorobenzene................................................... 0.95C + 0.02 0.09X + 0.23 0.17X + 0.10
1,2-Dichlorobenzene............................................. 0.93C + 0.52 0.17X-0.04 0.22X + 0.53
1,3-Dichlorobenzene............................................. 0.96C-0.05 0.15X-0.10 0.19X + 0.09
1,4-Dichlorobenzene............................................. 0.93C-0.09 0.15X + 0.28 0.20X + 0.41
Ethylbenzene.................................................... 0.94C + 0.31 0.17X + 0.46 0.26X + 0.23
Toluene......................................................... 0.94C + 0.65 0.09X + 0.48 0.18X + 0.71
----------------------------------------------------------------------------------------------------------------
X' = Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/L.
S' = Expected single analyst standard deviation of measurements at an average concentration found of X, in X
[micro]g/L.
S' = Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C = True value for the Concentration, in [micro]g/L.
X = Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
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Method 603--Acrolein and Acrylonitrile
1. Scope and Application
1.1 This method covers the determination of acrolein and
acrylonitrile. The following parameters may be determined by this
method:
------------------------------------------------------------------------
STORET
Parameter No. CAS No.
------------------------------------------------------------------------
Acrolein......................................... 34210 107-02-8
Acrylonitrile.................................... 34215 107-13-1
------------------------------------------------------------------------
1.2 This is a purge and trap gas chromatographic (GC) method
applicable to the determination of the compounds listed above in
municipal and industrial discharges as provided under 40 CFR 136.1. When
this method is used to analyze unfamiliar samples for either or both of
the compounds above, compound identifications should be supported by at
least one additional qualitative technique. This method describes
analytical conditions for a second gas chromatographic column that can
be used to confirm measurements made with the primary column. Method 624
provides gas chromatograph/mass spectrometer (GC/MS) conditions
appropriate for the qualitative and quantitative confirmation of results
for the parameters listed above, if used with the purge and trap
conditions described in this method.
1.3 The method detection limit (MDL, defined in Section 12.1) \1\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
1.4 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.5 This method is restricted to use by or under the supervision of
analysts experienced in the operation of a purge and trap system and a
gas chromatograph and in the interpretation of gas chromatograms. Each
analyst must demonstrate the ability to generate acceptable results with
this method using the procedure described in Section 8.2.
2. Summary of Method
2.1 An inert gas is bubbled through a 5-mL water sample contained in
a heated purging chamber. Acrolein and acrylonitrile are transferred
from the aqueous phase to the vapor phase. The vapor is swept through a
sorbent trap where the analytes are trapped. After the purge is
completed, the trap is heated and backflushed with the inert gas to
desorb the compound onto a gas chromatographic column. The gas
chromatograph is temperature programmed to separate the analytes which
are then detected with a flame ionization detector. \2 3\
2.2 The method provides an optional gas chromatographic column that
may be helpful in resolving the compounds of interest from the
interferences that may occur.
3. Interferences
3.1 Impurities in the purge gas and organic compound outgassing from
the plumbing of the trap account for the majority of contamination
problems. The analytical system must be demonstrated to be free from
contamination under the conditions of the analysis by running laboratory
reagent blanks as described in Section 8.1.3. The use of non-Teflon
plastic tubing, non-Teflon thread sealants, or flow controllers with
rubber components in the purge and trap system should be avoided.
3.2 Samples can be contaminated by diffusion of volatile organics
through the septum seal into the sample during shipment and storage. A
field reagent blank prepared from reagent water and carried through the
sampling and handling protocol can serve as a check on such
contamination.
3.3 Contamination by carry-over can occur whenever high level and
low level samples are sequentially analyzed. To reduce carry-over, the
purging device and sample syringe must be rinsed between samples with
reagent water. Whenever an unusually concentrated sample is encountered,
it should be followed by an analysis of reagent water to check for cross
contamination. For samples containing large amounts of water-soluble
materials, suspended solids, high boiling compounds or high analyte
levels, it may be necessary to wash the purging device with a detergent
solution, rinse it with distilled water, and then dry it in an oven at
105 [deg]C between analyses. The trap and other parts of the system are
also subject to contamination, therefore, frequent bakeout and purging
of the entire system may be required.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this view point,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified
4 6 for the information of the analyst.
[[Page 103]]
5. Apparatus and Materials
5.1 Sampling equipment, for discrete sampling.
5.1.1 Vial--25-mL capacity or larger, equipped with a screw cap with
a hole in the center (Pierce 13075 or equivalent). Detergent wash,
rinse with tap and distilled water, and dry at 105 [deg]C before use.
5.1.2 Septum--Teflon-faced silicone (Pierce 12722 or equivalent).
Detergent wash, rinse with tap and distilled water and dry at 105 [deg]C
for 1 h before use.
5.2 Purge and trap system--The purge and trap system consists of
three separate pieces of equipment: a purging device, trap, and
desorber. Several complete systems are now commercially available.
5.2.1 The purging device must be designed to accept 5-mL, samples
with a water column at least 3 cm deep. The gaseous head space between
the water column and the trap must have a total volume of less than 15
mL. The purge gas must pass through the water column as finely divided
bubbles with a diameter of less than 3 mm at the origin. The purge gas
must be introduced no more than 5 mm from the base of the water column.
The purging device must be capable of being heated to 85 [deg]C within
3.0 min after transfer of the sample to the purging device and being
held at 85 2 [deg]C during the purge cycle. The
entire water column in the purging device must be heated. Design of this
modification to the standard purging device is optional, however, use of
a water bath is suggested.
5.2.1.1 Heating mantle--To be used to heat water bath.
5.2.1.2 Temperature controller--Equipped with thermocouple/sensor to
accurately control water bath temperature to 2
[deg]C. The purging device illustrated in Figure 1 meets these design
criteria.
5.2.2 The trap must be at least 25 cm long and have an inside
diameter of at least 0.105 in. The trap must be packed to contain 1.0 cm
of methyl silicone coated packing (Section 6.5.2) and 23 cm of 2,6-
diphenylene oxide polymer (Section 6.5.1). The minimum specifications
for the trap are illustrated in Figure 2.
5.2.3 The desorber must be capable of rapidly heating the trap to
180 [deg]C, The desorber illustrated in Figure 2 meets these design
criteria.
5.2.4 The purge and trap system may be assembled as a separate unit
as illustrated in Figure 3 or be coupled to a gas chromatograph.
5.3 pH paper--Narrow pH range, about 3.5 to 5.5 (Fisher Scientific
Short Range Alkacid No. 2, 14-837-2 or equivalent).
5.4 Gas chromatograph--An analytical system complete with a
temperature programmable gas chromatograph suitable for on-column
injection and all required accessories including syringes, analytical
columns, gases, detector, and strip-chart recorder. A data system is
recommended for measuring peak areas.
5.4.1 Column 1--10 ft long x 2 mm ID glass or stainless steel,
packed with Porapak-QS (80/100 mesh) or equivalent. This column was used
to develop the method performance statements in Section 12. Guidelines
for the use of alternate column packings are provided in Section 10.1.
5.4.2 Column 2--6 ft long x 0.1 in. ID glass or stainless steel,
packed with Chromosorb 101 (60/80 mesh) or equivalent.
5.4.3 Detector--Flame ionization detector. This type of detector has
proven effective in the analysis of wastewaters for the parameters
listed in the scope (Section 1.1), and was used to develop the method
performance statements in Section 12. Guidelines for the use of
alternate detectors are provided in Section 10.1.
5.5 Syringes--5-mL, glass hypodermic with Luerlok tip (two each).
5.6 Micro syringes--25-[micro]L, 0.006 in. ID needle.
5.7 Syringe valve--2-way, with Luer ends (three each).
5.8 Bottle--15-mL, screw-cap, with Teflon cap liner.
5.9 Balance--Analytical, capable of accurately weighing 0.0001 g.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.1.1 Reagent water can be generated by passing tap water through a
carbon filter bed containing about 1 lb of activated carbon (Filtrasorb-
300, Calgon Corp., or equivalent).
6.1.2 A water purification system (Millipore Super-Q or equivalent)
may be used to generate reagent water.
6.1.3 Regent water may also be prepared by boiling water for 15 min.
Subsequently, while maintaining the temperature at 90 [deg]C, bubble a
contaminant-free inert gas through the water for 1 h. While still hot,
transfer the water to a narrow mouth screw-cap bottle and seal with a
Teflon-lined septum and cap.
6.2 Sodium thiosulfate--(ACS) Granular.
6.3 Sodium hydroxide solution (10 N)--Dissolve 40 g of NaOH (ACS) in
reagent water and dilute to 100 mL.
6.4 Hydrochloric acid (1 + 1)--Slowly, add 50 mL of concentrated HCl
(ACS) to 50 mL of reagent water.
6.5 Trap Materials:
6.5.1 2,6-Diphenylene oxide polymer--Tenax (60/80 mesh),
chromatographic grade or equivalent.
6.5.2 Methyl silicone packing--3% OV-1 on Chromosorb-W (60/80 mesh)
or equivalent.
[[Page 104]]
6.6 Stock standard solutions--Stock standard solutions may be
prepared from pure standard materials or purchased as certified
solutions. Prepare stock standard solutions in reagent water using
assayed liquids. Since acrolein and acrylonitrile are lachrymators,
primary dilutions of these compounds should be prepared in a hood. A
NIOSH/MESA approved toxic gas respirator should be used when the analyst
handles high concentrations of such materials.
6.6.1 Place about 9.8 mL of reagent water into a 10-mL ground glass
stoppered volumetric flask. For acrolein standards the reagent water
must be adjusted to pH 4 to 5. Weight the flask to the nearest 0.1 mg.
6.6.2 Using a 100-[micro]L syringe, immediately add two or more
drops of assayed reference material to the flask, then reweigh. Be sure
that the drops fall directly into the water without contacting the neck
of the flask.
6.6.3 Reweigh, dilute to volume, stopper, then mix by inverting the
flask several times. Calculate the concentration in [micro]g/[micro]L
from the net gain in weight. When compound purity is assayed to be 96%
or greater, the weight can be used without correction to calculate the
concentration of the stock staldard. Optionally, stock standard
solutions may be prepared using the pure standard material by
volumetrically measuring the appropriate amounts and determining the
weight of the material using the density of the material. Commercially
prepared stock standards may be used at any concentration if they are
certified by the manufactaurer or by an independent source.
6.6.4 Transfer the stock standard solution into a Teflon-sealed
screw-cap bottle. Store at 4 [deg]C and protect from light.
6.6.5 Prepare fresh standards daily.
6.7 Secondary dilution standards--Using stock standard solutions,
prepare secondary dilution standards in reagent water that contain the
compounds of interest, either singly or mixed together. The secondary
dilution standards should be prepared at concentrations such that the
aqueous calibration standards prepared in Section 7.3.1 or 7.4.1 will
bracket the working range of the analytical system. Secondary dilution
standards should be prepared daily and stored at 4 [deg]C.
6.8 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Assemble a purge and trap system that meets the specifications
in Section 5.2. Condition the trap overnight at 180 [deg]C by
backflushing with an inert gas flow of at least 20 mL/min. Condition the
trap for 10 min once daily prior to use.
7.2 Connect the purge and trap system to a gas chromatograph. The
gas chromatograph must be operated using temperature and flow rate
conditions equivalent to those given in Table 1. Calibrate the purge and
trap-gas chromatographic system using either the external standard
technique (Section 7.3) or the internal standard technique (Section
7.4).
7.3 External standard calibration procedure:
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter by carefully adding 20.0
[micro]L of one or more secondary dilution standards to 100, 500, or
1000 mL of reagent water. A 25-[micro]L syringe with a 0.006 in. ID
needle should be used for this operation. One of the external standards
should be at a concentration near, but above, the MDL and the other
concentrations should correspond to the expected range of concentrations
found in real samples or should define the working range of the
detector. These standards must be prepared fresh daily.
7.3.2 Analyze each calibration standard according to Section 10, and
tabulate peak height or area responses versus the concentration of the
standard. The results can be used to prepare a calibration curve for
each compound. Alternatively, if the ratio of response to concentration
(calibration factor) is a constant over the working range (<10% relative
standard deviation, RSD), linearity through the origin can be assumed
and the average ratio or calibration factor can be used in place of a
calibration curve.
7.4 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the compounds of interest. The analyst must
further demonstrate that the measurement of the internal standard is not
affected by method or matrix interferences. Because of these
limitations, no internal standard can be suggested that is applicable to
all samples.
7.4.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest as described in
Section 7.3.1.
7.4.2 Prepare a spiking solution containing each of the internal
standards using the procedures described in Sections 6.6 and 6.7. It is
recommended that the secondary dilution standard be prepared at a
concentration of 15 [micro]g/mL of each internal standard compound. The
addition of 10 [micro]L of this standard to 5.0 mL of sample or
calibration standard would be equivalent to 30 [micro]g/L.
7.4.3 Analyze each calibration standard according to Section 10,
adding 10 [micro]L of internal standard spiking solution directly to the
syringe (Section 10.4). Tabulate peak height or area responses against
concentration for each compound and internal standard, and calculate
response factors (RF) for each compound using Equation 1.
RF = (As)(Cis (Ais)(Cs)
Equation 1
[[Page 105]]
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Cis = Concentration of the internal standard.
Cs = Concentration of the parameter to be measured.
If the RF value over the working range is a constant (<10% RSD), the RF
can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.5 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of a QC check sample.
7.5.1 Prepare the QC check sample as described in Section 8.2.2.
7.5.2 Analyze the QC check sample according to Section 10.
7.5.3 For each parameter, compare the response (Q) with the
corresponding calibration acceptance criteria found in Table 2. If the
responses for all parameters of interest fall within the designated
ranges, analysis of actual samples can begin. If any individual Q falls
outside the range, a new calibration curve, calibration factor, or RF
must be prepared for that parameter according to Section 7.3 or 7.4.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Section 10.1) to improve the separations or lower the cost of
measurements. Each time such a modification is made to the method, the
analyst is required to repeat the procedure in Section 8.2.
8.1.3 Each day, the analyst must analyze a reagent water blank to
demonstrate that interferences from the analytical system are under
control.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing each parameter of interest at a concentration of 25 [micro]g/
mL in reagent water. The QC check sample concentrate must be obtained
from the U.S. Environmental Protection Agency, Environmental Monitoring
and Support Laboratory in Cincinnati, Ohio, if available. If not
available from that source, the QC check sample concentrate must be
obtained from another external source. If not available from either
source above, the QC check sample concentrate must be prepared by the
laboratory using stock standards prepared independently from those used
for calibration.
8.2.2 Prepare a QC check sample to contain 50 [micro]g/L of each
parameter by adding 200 [micro]L of QC check sample concentrate to 100
mL of reagent water.
8.2.3 Analyze four 5-mL aliquots of the well-mixed QC check sample
according to Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 3. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If either s exceeds the precision limit or X falls
outside the range for accuracy, the system performance is unacceptable
for that parameter. Locate and correct the source of the problem and
repeat the test for each compound of interest.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to
[[Page 106]]
ten samples per month, at least one spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at 50 [micro]g/L or 1 to 5 times higher than the
background concentration determined in Section 8.3.2, whichever
concentration would be larger.
8.3.2 Analyze one 5-mL sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second 5-mL sample aliquot with 10
[micro]L of the QC check sample concentrate and analyze it to determine
the concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100(A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 3. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\7\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory.
8.4.1 Prepare the QC check standard by adding 10 [micro]L of QC
check sample concentrate (Section 8.2.1 or 8.3.2) to 5 mL of reagent
water. The QC check standard needs only to contain the parameters that
failed criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
3. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2sp to P + 2sp.
If P = 90% and sp = 10%, for example, the accuracy interval
is expressed as 70-110%. Update the accuracy assessment for each
parameter on a regular basis (e.g. after each five to ten new accuracy
measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as gas chromatography with a dissimilar column or mass spectrometer
must be used. Whenever possible, the laboratory should analyze standard
reference materials and participate in relevant performance evaluation
studies.
9. Sample Collection, Preservation, and Handling
9.1 All samples must be iced or refrigerated from the time of
collection until analysis. If the sample contains free or combined
chlorine, add sodium thiosulfate preservative (10 mg/40 mL is sufficient
for up to 5 ppm Cl2) to the empty sample bottle just prior to
shipping to the sampling site. EPA Methods 330.4 and 330.5 may be used
for measurement of residual chlorine. \8\ Field test kits are available
for this purpose.
9.2 If acrolein is to be analyzed, collect about 500 mL of sample in
a clean glass container. Adjust the pH of the sample to 4 to 5 using
acid or base, measuring with narrow range pH paper. Samples for acrolein
analysis receiving no pH adjustment must be analyzed within 3 days of
sampling.
[[Page 107]]
9.3 Grab samples must be collected in glass containers having a
total volume of at least 25 mL. Fill the sample bottle just to
overflowing in such a manner that no air bubbles pass through the sample
as the bottle is being filled. Seal the bottle so that no air bubbles
are entrapped in it. If preservative has been added, shake vigorously
for 1 min. Maintain the hermetic seal on the sample bottle until time of
analysis.
9.4 All samples must be analyzed within 14 days of collection. \3\
10. Procedure
10.1 Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are estimated retention times
and MDL that can be achieved under these conditions. An example of the
separations achieved by Column 1 is shown in Figure 5. Other packed
columns, chromatographic conditions, or detectors may be used if the
requirements of Section 8.2 are met.
10.2 Calibrate the system daily as described in Section 7.
10.3 Adjust the purge gas (nitrogen or helium) flow rate to 20 mL-
min. Attach the trap inlet to the purging device, and set the purge and
trap system to purge (Figure 3). Open the syringe valve located on the
purging device sample introduction needle.
10.4 Remove the plunger from a 5-mL syringe and attach a closed
syringe valve. Open the sample bottle (or standard) and carefully pour
the sample into the syringe barrel to just short of overflowing. Replace
the syringe plunger and compress the sample. Open the syringe valve and
vent any residual air while adjusting the sample volume to 5.0 mL. Since
this process of taking an aliquot destroys the validity of the sample
for future analysis, the analyst should fill a second syringe at this
time to protect against possible loss of data. Add 10.0 [micro]L of the
internal standard spiking solution (Section 7.4.2), if applicable,
through the valve bore then close the valve.
10.5 Attach the syringe-syringe valve assembly to the syringe valve
on the purging device. Open the syringe valves and inject the sample
into the purging chamber.
10.6 Close both valves and purge the sample for 15.0 0.1 min while heating at 85 2
[deg]C.
10.7 After the 15-min purge time, attach the trap to the
chromatograph, adjust the purge and trap system to the desorb mode
(Figure 4), and begin to temperature program the gas chromatograph.
Introduce the trapped materials to the GC column by rapidly heating the
trap to 180 [deg]C while backflushing the trap with an inert gas between
20 and 60 mL/min for 1.5 min.
10.8 While the trap is being desorbed into the gas chromatograph,
empty the purging chamber using the sample introduction syringe. Wash
the chamber with two 5-mL flushes of reagent water.
10.9 After desorbing the sample for 1.5 min, recondition the trap by
returning the purge and trap system to the purge mode. Wait 15 s then
close the syringe valve on the purging device to begin gas flow through
the trap. The trap temperature should be maintained at 210 [deg]C. After
approximately 7 min, turn off the trap heater and open the syringe valve
to stop the gas flow through the trap. When the trap is cool, the next
sample can be analyzed.
10.10 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
11. Calculations
11.1 Determine the concentration of individual compounds in the
sample.
11.1.1 If the external standard calibration procedure is used,
calculate the concentration of the parameter being measured from the
peak response using the calibration curve or calibration factor
determined in Section 7.3.2.
11.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.4.3 and Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.097
Equation 2
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Cis = Concentration of the internal standard.
11.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
12. Method Performance
12.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentrations
listed in Table 1 were obtained using reagent water. \9\
[[Page 108]]
The MDL actually achieved in a given analysis will vary depending on
instrument sensitivity and matrix effects.
12.2 This method is recommended for the concentration range from the
MDL to 1,000 x MDL. Direct aqueous injection techniques should be used
to measure concentration levels above 1,000 x MDL.
12.3 In a single laboratory (Battelle-Columbus), the average
recoveries and standard deviations presented in Table 2 were obtained.
\9\ Seven replicate samples were analyzed at each spike level.
References
1. 40 CFR part 136, appendix B.
2. Bellar, T.A., and Lichtenberg, J.J. ``Determining Volatile
Organics at Microgram-per-Litre-Levels by Gas Chromatography,'' Journal
American Water Works Association, 66, 739 (1974).
3. ``Evaluate Test Procedures for Acrolein and Acrylonitrile,''
Special letter report for EPA Project 4719-A, U.S. Environmental
Protection Agency, Environmental Monitoring and Support Laboratory,
Cincinnati, Ohio 45268, 27 June 1979.
4. ``Carcinogens--Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
6. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983).
8. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268, March 1979.
9. ``Evaluation of Method 603 (Modified),'' EPA-600/4-84-ABC,
National Technical Information Service, PB84-, Springfield, Virginia
22161, Nov. 1984.
Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
Retention time (min) Method
------------------------ detection
Parameter limit
Column 1 Column 2 ([micro]g/
L)
------------------------------------------------------------------------
Acrolein............................ 10.6 8.2 0.7
Acrylonitrile....................... 12.7 9.8 0.5
------------------------------------------------------------------------
Column 1 conditions: Porapak-QS (80/100 mesh) packed in a 10 ft x 2 mm
ID glass or stainless steel column with helium carrier gas at 30 mL/
min flow rate. Column temperature held isothermal at 110 [deg]C for
1.5 min (during desorption), then heated as rapidly as possible to 150
[deg]C and held for 20 min; column bakeout at 190 [deg]C for 10 min.
\9\
Column 2 conditions: Chromosorb 101 (60/80 mesh) packed in a 6 ft. x 0.1
in. ID glass or stainless steel column with helium carrier gas at 40
mL/min flow rate. Column temperature held isothermal at 80 [deg]C for
4 min, then programmed at 50 [deg]C/min to 120 [deg]C and held for 12
min.
Table 2--Single Laboratory Accuracy and Precision--Method 603
----------------------------------------------------------------------------------------------------------------
Spike Average Standard
Sample conc. recovery deviation Average
Parameter matrix ([micro]g/ ([micro]g/ ([micro]g/ percent
L) L) L) recovery
----------------------------------------------------------------------------------------------------------------
Acrolein............................................... RW 5.0 5.2 0.2 104
RW 50.0 51.4 0.7 103
POTW 5.0 4.0 0.2 80
POTW 50.0 44.4 0.8 89
IW 5.0 0.1 0.1 2
IW 100.0 9.3 1.1 9
Acrylonitrile.......................................... RW 5.0 4.2 0.2 84
RW 50.0 51.4 1.5 103
POTW 20.0 20.1 0.8 100
POTW 100.0 101.3 1.5 101
IW 10.0 9.1 0.8 91
IW 100.0 104.0 3.2 104
----------------------------------------------------------------------------------------------------------------
RW = Reagent water.
POTW = Prechlorination secondary effluent from a municipal sewage treatment plant.
IW = Industrial wastewater containing an unidentified acrolein reactant.
Table 3--Calibration and QC Acceptance Criteria--Method 603 \a\
----------------------------------------------------------------------------------------------------------------
Limit for
Range for Q S Range for X Range for
Parameter ([micro]g/ ([micro]g/ ([micro]g/ P, Ps (%)
L) L) L)
----------------------------------------------------------------------------------------------------------------
Acrolein..................................................... 45.9-54.1 4.6 42.9-60.1 88-118
[[Page 109]]
Acrylonitrile................................................ 41.2-58.8 9.9 33.1-69.9 71-135
----------------------------------------------------------------------------------------------------------------
\a\ = Criteria were calculated assuming a QC check sample concentration of 50 [micro]g/L. \9\
Q = Concentration measured in QC check sample, in [micro]g/L (Section 7.5.3).
s = Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X = Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps = Percent recovery measured (Section 8.3.2, Section 8.4.2).
[GRAPHIC] [TIFF OMITTED] TC02JY92.008
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[GRAPHIC] [TIFF OMITTED] TC02JY92.009
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Method 604--Phenols
1. Scope and Application
1.1 This method covers the determination of phenol and certain
substituted phenols. The following parameters may be determined by this
method:
------------------------------------------------------------------------
STORET
Parameter No. CAS No.
------------------------------------------------------------------------
4-Chloro-3-methylphenol.......................... 34452 59-50-7
2--Chlorophenol.................................. 34586 95-57-8
2,4-Dichlorophenol............................... 34601 120-83-2
2,4-Dimethylphenol............................... 34606 105-67-9
2,4-Dinitrophenol................................ 34616 51-28-5
2-Methyl-4,6-dinitrophenol....................... 34657 534-52-1
2-Nitrophenol.................................... 34591 88-75-5
4-Nitrophenol.................................... 34646 100-02-7
Pentachlorophenol................................ 39032 87-86-5
Phenol........................................... 34694 108-95-2
2,4,6-Trichlorophenol............................ 34621 88-06-2
------------------------------------------------------------------------
1.2 This is a flame ionization detector gas chromatographic (FIDGC)
method applicable to the determination of the compounds listed above in
municipal and industrial discharges as provided under 40 CFR 136.1. When
this method is used to analyze unfamiliar samples for any or all of the
compounds above, compound identifications should be supported by at
least one additional qualitative technique. This method describes
analytical conditions for derivatization, cleanup, and electron capture
detector gas chromatography (ECDGC) that can be used to confirm
measurements made by FIDGC. Method 625 provides gas chromatograph/mass
spectrometer (GC/MS) conditions appropriate for the qualitative and
quantitative confirmation of results for all of the parameters listed
above, using the extract produced by this method.
1.3 The method detection limit (MDL, defined in Section 14.1) \1\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix. The MDL listed in Table 1 for each
parameter was achieved with a flame ionization detector (FID). The MDLs
that were achieved when the derivatization cleanup and electron capture
detector (ECD) were employed are presented in Table 2.
[[Page 113]]
1.4 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.5 This method is restricted to use by or under the supervision of
analysts experienced in the use of a gas chromatograph and in the
interpretation of gas chromatograms. Each analyst must demonstrate the
ability to generate acceptable results with this method using the
procedure described in Section 8.2.
2. Summary of Method
2.1 A measured volume of sample, approximately 1-L, is acidified and
extracted with methylene chloride using a separatory funnel. The
methylene chloride extract is dried and exchanged to 2-propanol during
concentration to a volume of 10 mL or less. The extract is separated by
gas chromatography and the phenols are then measured with an FID. \2\
2.2 A preliminary sample wash under basic conditions can be employed
for samples having high general organic and organic base interferences.
2.3 The method also provides for a derivatization and column
chromatography cleanup procedure to aid in the elimination of
interferences. 2 3 The derivatives are analyzed by ECDGC.
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardware that lead to
discrete artifacts and/or elevated baselines in gas chromatograms. All
of these materials must be routinely demonstrated to be free from
interferences under the conditions of the analysis by running laboratory
reagent blanks as described in Section 8.1.3.
3.1.1 Glassware must be scrupulously cleaned. \4\ Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed by detergent washing with
hot water, and rinses with tap water and distilled water. The glassware
should then be drained dry, and heated in a muffle furnace at 400 [deg]C
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not
be eliminated by this treatment. Solvent rinses with acetone and
pesticide quality hexane may be substituted for the muffle furnace
heating. Thorough rinsing with such solvents usually eliminates PCB
interference. Volumetric ware should not be heated in a muffle furnace.
After drying and cooling, glassware should be sealed and stored in a
clean environment to prevent any accumulation of dust or other
contaminants. Store inverted or capped with aluminum foil.
3.1.2 The use of high purity reagents and solvents helps to minimize
interference problems. Purification of solvents by distillation in all-
glass systems may be required.
3.2 Matrix interferences may be caused by contaminants that are
coextracted from the sample. The extent of matrix interferences will
vary considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled. The
derivatization cleanup procedure in Section 12 can be used to overcome
many of these interferences, but unique samples may require additional
cleanup approaches to achieve the MDL listed in Tables 1 and 2.
3.3 The basic sample wash (Section 10.2) may cause significantly
reduced recovery of phenol and 2,4-dimethylphenol. The analyst must
recognize that results obtained under these conditions are minimum
concentrations.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
mothod has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified
5 7 for the information of analyst.
4.2 Special care should be taken in handling pentafluorobenzyl
bromide, which is a lachrymator, and 18-crown-6-ether, which is highly
toxic.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--1-L or 1-qt, amber glass, fitted with a
screw cap lined with Teflon. Foil may be substituted for Teflon if the
sample is not corrosive. If amber bottles are not available, protect
samples from light. The bottle and cap liner must be washed, rinsed with
acetone or methylene chloride, and dried before use to minimize
contamination.
5.1.2 Automatic sampler (optional)--The sampler must incorporate
glass sample containers for the collection of a minimum of 250 mL of
sample. Sample containers must be kept refrigerated at 4 [deg]C and
protected from light during compositing. If the sampler uses a
peristaltic pump, a minimum length of compressible silicone rubber
tubing may be
[[Page 114]]
used. Before use, however, the compressible tubing should be thoroughly
rinsed with methanol, followed by repeated rinsings with distilled water
to minimize the potential for contamination of the sample. An
integrating flow meter is required to collect flow proportional
composites.
5.2 Glassware (All specifications are suggested. Catalog numbers are
included for illustration only.):
5.2.1 Separatory funnel--2-L, with Teflon stopcock.
5.2.2 Drying column--Chromatographic column, 400 mm long x 19 mm ID,
with coarse frit filter disc.
5.2.3 Chromatographic column--100 mm long x 10 mm ID, with Teflon
stopcock.
5.2.4 Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes K-
570050-1025 or equivalent). Calibration must be checked at the volumes
employed in the test. Ground glass stopper is used to prevent
evaporation of extracts.
5.2.5 Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
5.2.6 Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
5.2.7 Snyder column, Kuderna-Danish--Two-ball micro (Kontes K-
569001-0219 or equivalent).
5.2.8 Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
5.2.9 Reaction flask--15 to 25-mL round bottom flask, with standard
tapered joint, fitted with a water-cooled condenser and U-shaped drying
tube containing granular calcium chloride.
5.3 Boiling chips--Approximately 10/40 mesh. Heat to 400 [deg]C for
30 min or Soxhlet extract with methylene chloride.
5.4 Water bath--Heated, with concentric ring cover, capable of
temperature control (2 [deg]C). The bath should be
used in a hood.
5.5 Balance--Analytical, capable of accurately weighting 0.0001 g.
5.6 Gas chromatograph--An analytical system complete with a
temperature programmable gas chromatograph suitable for on-column
injection and all required accessories including syringes, analytical
columns, gases, detector, and strip-chart recorder. A data system is
recommended for measuring peak areas.
5.6.1 Column for underivatized phenols--1.8 m long x 2 mm ID glass,
packed with 1% SP-1240DA on Supelcoport (80/100 mesh) or equivalent.
This column was used to develop the method performance statements in
Section 14. Guidelines for the use of alternate column packings are
provided in Section 11.1.
5.6.2 Column for derivatized phenols--1.8 m long x 2 mm ID glass,
packed with 5% OV-17 on Chromosorb W-AW-DMCS (80/100 mesh) or
equivalent. This column has proven effective in the analysis of
wastewaters for derivatization products of the parameters listed in the
scope (Section 1.1), and was used to develop the method performance
statements in Section 14. Guidelines for the use of alternate column
packings are provided in Section 11.1.
5.6.3 Detectors--Flame ionization and electron capture detectors.
The FID is used when determining the parent phenols. The ECD is used
when determining the derivatized phenols. Guidelines for the use of
alternatve detectors are provided in Section 11.1.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.2 Sodium hydroxide solution (10 N)--Dissolve 40 g of NaOH (ACS) in
reagent water and dilute to 100 mL.
6.3 Sodium hydroxide solution (1 N)--Dissolve 4 g of NaOH (ACS) in
reagent water and dilute to 100 mL.
6.4 Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at
400 [deg]C for 4 h in a shallow tray.
6.5 Sodium thiosulfate--(ACS) Granular.
6.6 Sulfuric acid (1 + 1)--Slowly, add 50 mL of
H2SO4 (ACS, sp. gr. 1.84) to 50 mL of reagent
water.
6.7 Sulfuric acid (1 N)--Slowly, add 58 mL of
H2SO4 (ACS, sp. gr. 1.84) to reagent water and
dilute to 1 L.
6.8 Potassium carbonate--(ACS) Powdered.
6.9 Pentafluorobenzyl bromide ([alpha]-Bromopentafluorotoluene)--97%
minimum purity.
Note: This chemical is a lachrymator. (See Section 4.2.)
6.10 18-crown-6-ether (1,4,7,10,13,16-Hexaoxacyclooctadecane)--98%
minimum purity.
Note: This chemical is highly toxic.
6.11 Derivatization reagent--Add 1 mL of pentafluorobenzyl bromide
and 1 g of 18-crown-6-ether to a 50-mL volumetric flask and dilute to
volume with 2-propanol. Prepare fresh weekly. This operation should be
carried out in a hood. Store at 4 [deg]C and protect from light.
6.12 Acetone, hexane, methanol, methylene chloride, 2-propanol,
toluene--Pesticide quality or equivalent.
6.13 Silica gel--100/200 mesh, Davison, grade-923 or equivalent.
Activate at 130 [deg]C overnight and store in a desiccator.
6.14 Stock standard solutions (1.00 [micro]g/[micro]L)--Stock
standard solutions may be prepared from pure standard materials or
purchased as certified solutions.
6.14.1 Prepare stock standard solutions by accurately weighing about
0.0100 g of pure material. Dissolve the material in 2-propanol
[[Page 115]]
and dilute to volume in a 10-mL volumetric flask. Larger volumes can be
used at the convenience of the analyst. When compound purity is assayed
to be 96% or greater, the weight can be used without correction to
calculate the concentration of the stock standard. Commercially prepared
stock standards can be used at any concentration if they are certified
by the manufacturer or by an independent source.
6.14.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles. Store at 4 [deg]C and protect from light. Stock
standard solutions should be checked frequently for signs of degradation
or evaporation, especially just prior to preparing calibration standards
from them.
6.14.3 Stock standard solutions must be replaced after six months,
or sooner if comparison with check standards indicates a problem.
6.15 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 To calibrate the FIDGC for the anaylsis of underivatized
phenols, establish gas chromatographic operating conditions equivalent
to those given in Table 1. The gas chromatographic system can be
calibrated using the external standard technique (Section 7.2) or the
internal standard technique (Section 7.3).
7.2 External standard calibration procedure for FIDGC:
7.2.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask and diluting to volume
with 2-propanol. One of the external standards should be at a
concentration near, but above, the MDL (Table 1) and the other
concentrations should correspond to the expected range of concentrations
found in real samples or should define the working range of the
detector.
7.2.2 Using injections of 2 to 5 [micro]l, analyze each calibration
standard according to Section 11 and tabulate peak height or area
responses against the mass injected. The results can be used to prepare
a calibration curve for each compound. Alternatively, if the ratio of
response to amount injected (calibration factor) is a constant over the
working range (<10% relative standard deviation, RSD), linearity through
the origin can be assumed and the average ratio or calibration factor
can be used in place of a calibration curve.
7.3 Internal standard calibration procedure for FIDGC--To use this
approach, the analyst must select one or more internal standards that
are similar in analytical behavior to the compounds of interest. The
analyst must further demonstrate that the measurement of the internal
standard is not affected by method or matrix interferences. Because of
these limitations, no internal standard can be suggested that is
applicable to all samples.
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask. To each calibration
standard, add a known constant amount of one or more internal standards,
and dilute to volume with 2-propanol. One of the standards should be at
a concentration near, but above, the MDL and the other concentrations
should correspond to the expected range of concentrations found in real
samples or should define the working range of the detector.
7.3.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 11 and tabulate peak height or area
responses against concentration for each compound and internal standard.
Calculate response factors (RF) for each compound using Equation 1.
RF = (As)(Cis (Ais)(Cs)
Equation 1
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Cis = Concentration of the internal standard ([micro]g/L).
Cs = Concentration of the parameter to be measured ([micro]g/
L).
If the RF value over the working range is a constant (<10% RSD), the
RF can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.4 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of one or more
calibration standards. If the response for any parameter varies from the
predicted response by more than 15%, a new
calibration curve must be prepared for that compound.
7.5 To calibrate the ECDGC for the analysis of phenol derivatives,
establish gas chromatographic operating conditions equivalent to those
given in Table 2.
7.5.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask and diluting to volume
with 2-propanol. One of the external standards should be at a
concentration near, but above, the MDL (Table 2) and the other
concentrations should correspond to the expected range of concentrations
found in real samples or should define the working range of the
detector.
[[Page 116]]
7.5.2 Each time samples are to be derivatized, simultaneously treat
a 1-mL aliquot of each calibration standard as described in Section 12.
7.5.3 After derivatization, analyze 2 to 5 [micro]L of each column
eluate collected according to the method beginning in Section 12.8 and
tabulate peak height or area responses against the calculated equivalent
mass of underivatized phenol injected. The results can be used to
prepare a calibration curve for each compound.
7.6 Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the reagents.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Sections 10.6 and 11.1) to improve the separations or lower the cost of
measurements. Each time such a modification is made to the method, the
analyst is required to repeat the procedure in Section 8.2.
8.1.3 Before processing any samples the analyst must analyze a
reagent water blank to demonstrate that interferences from the
analytical system and glassware are under control. Each time a set of
samples is extracted or reagents are changed a reagent water blank must
be processed as a safeguard against laboratory contamination.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing each parameter of interest at a concentration of 100
[micro]g/mL in 2-propanol. The QC check sample concentrate must be
obtained from the U.S. Environmental Protection Agency, Environmental
Monitoring and Support Laboratory in Cincinnati, Ohio, if available. If
not available from that source, the QC check sample concentrate must be
obtained from another external source. If not available from either
source above, the QC check sample concentrate must be prepared by the
laboratory using stock standards prepared independently from those used
for calibration.
8.2.2 Using a pipet, prepare QC check samples at a concentration of
100 [micro]g/L by adding 1.00 mL of QC check sample concentrate to each
of four 1-L aliquots of reagent water.
8.2.3 Analyze the well-mixed QC check samples according to the
method beginning in Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 3. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If any individual s exceeds the precision limit or
any individual X falls outside the range for accuracy, the system
performance is unacceptable for that parameter.
Note: The large number of parameters in Talbe 3 present a
substantial probability that one or more will fail at least one of the
acceptance criteria when all parameters are analyzed.
8.2.6 When one or more of the parameters tested fail at least one of
the acceptance criteria, the analyst must proceed according to Section
8.2.6.1 or 8.2.6.2.
8.2.6.1 Locate and correct the source of the problem and repeat the
test for all parameters of interest beginning with Section 8.2.2.
8.2.6.2 Beginning with Section 8.2.2, repeat the test only for those
parameters that failed to meet criteria. Repeated failure, however, will
confirm a general problem
[[Page 117]]
with the measurement system. If this occurs, locate and correct the
source of the problem and repeat the test for all compounds of interest
beginning with Section 8.2.2.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at 100 [micro]g/L or 1 to 5 times higher than the
background concentration determined in Section 8.3.2, whichever
concentration would be larger.
8.3.1.3 If it is impractical to determine background levels before
spiking (e.g., maximum holding times will be exceeded), the spike
concentration should be (1) the regulatory concentration limit, if any,
or, if none, (2) the larger of either 5 times higher than the expected
background concentration or 100 [micro]g/L.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second sample aliquot with 1.0 mL
of the QC check sample concentrate and analyze it to determine the
concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100(A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 3. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\8\ If spiking was performed at a concentration lower than 100 [micro]g/
L, the analyst must use either the QC acceptance criteria in Table 3, or
optional QC acceptance criteria calculated for the specific spike
concentration. To calculate optional acceptance criteria for the
recovery of a parameter: (1) Calculate accuracy (X') using the equation
in Table 4, substituting the spike concentration (T) for C; (2)
calculate overall precision (S') using the equation in Table 4,
substituting X' for X; (3) calculate the range for recovery at the spike
concentration as (100 X'/T)2.44(100 S'/T)%. \8\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory.
8.4.1 Prepare the QC check standard by adding 1.0 mL of QC check
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The
QC check standard needs only to contain the parameters that failed
criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
3. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2sp to P + 2sp.
If P = 90% and sp = 10%, for example, the accuracy interval
is expressed as 70-110%. Update the accuracy assessment for each
parameter on a regular basis (e.g. after each five to ten new accuracy
measurements).
8.6. It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When
[[Page 118]]
doubt exists over the identification of a peak on the chromatogram,
confirmatory techniques such as gas chromatography with a dissimilar
column, specific element detector, or mass spectrometer must be used.
Whenever possible, the laboratory should analyze standard reference
materials and participate in relevant performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices \9\ should be followed, except that the bottle must
not be prerinsed with sample before collection. Composite samples should
be collected in refrigerated glass containers in accordance with the
requirements of the program. Automatic sampling equipment must be as
free as possible of Tygon tubing and other potential sources of
contamination.
9.2 All samples must be iced or refrigerated at 4 [deg]C from the
time of collection until extraction. Fill the sample bottles and, if
residual chlorine is present, add 80 mg of sodium thiosulfate per liter
of sample and mix well. EPA Methods 330.4 and 330.5 may be used for
measurement of residual chlorine. \10\ Field test kits are available for
this purpose.
9.3 All samples must be extracted within 7 days of collection and
completely analyzed within 40 days of extraction. \2\
10. Sample Extraction
10.1 Mark the water meniscus on the side of sample bottle for later
determination of sample volume. Pour the entire sample into a 2-L
separatory funnel.
10.2 For samples high in organic content, the analyst may solvent
wash the sample at basic pH as prescribed in Sections 10.2.1 and 10.2.2
to remove potential method interferences. Prolonged or exhaustive
contact with solvent during the wash may result in low recovery of some
of the phenols, notably phenol and 2,4-dimethylphenol. For relatively
clean samples, the wash should be omitted and the extraction, beginning
with Section 10.3, should be followed.
10.2.1 Adjust the pH of the sample to 12.0 or greater with sodium
hydroxide solution.
10.2.2 Add 60 mL of methylene chloride to the sample by shaking the
funnel for 1 min with periodic venting to release excess pressure.
Discard the solvent layer. The wash can be repeated up to two additional
times if significant color is being removed.
10.3 Adjust the sample to a pH of 1 to 2 with sulfuric acid.
10.4 Add 60 mL of methylene chloride to the sample bottle, seal, and
shake 30 s to rinse the inner surface. Transfer the solvent to the
separatory funnel and extract the sample by shaking the funnel for 2
min. with periodic venting to release excess pressure. Allow the organic
layer to separate from the water phase for a minimum of 10 min. If the
emulsion interface between layers is more than one-third the volume of
the solvent layer, the analyst must employ mechanical techniques to
complete the phase separation. The optimum technique depends upon the
sample, but may include stirring, filtration of the emulsion through
glass wool, centrifugation, or other physical methods. Collect the
methylene chloride extract in a 250-mL Erlenmeyer flask.
10.5 Add a second 60-mL volume of methylene chloride to the sample
bottle and repeat the extraction procedure a second time, combining the
extracts in the Erlenmeyer flask. Perform a third extraction in the same
manner.
10.6 Assemble a Kuderna-Danish (K-D) concentrator by attaching a 10-
mL concentrator tube to a 500-mL evaporative flask. Other concentration
devices or techniques may be used in place of the K-D concentrator if
the requirements of Section 8.2 are met.
10.7 Pour the combined extract through a solvent-rinsed drying
column containing about 10 cm of anhydrous sodium sulfate, and collect
the extract in the K-D concentrator. Rinse the Erlenmeyer flask and
column with 20 to 30 mL of methylene chloride to complete the
quantitative transfer.
10.8 Add one or two clean boiling chips to the evaporative flask and
attach a three-ball Snyder column. Prewet the Snyder column by adding
about 1 mL of methylene chloride to the top. Place the K-D apparatus on
a hot water bath (60 to 65 [deg]C) so that the concentrator tube is
partially immersed in the hot water, and the entire lower rounded
surface of the flask is bathed with hot vapor. Adjust the vertical
position of the apparatus and the water temperature as required to
complete the concentration in 15 to 20 min. At the proper rate of
distillation the balls of the column will actively chatter but the
chambers will not flood with condensed solvent. When the apparent volume
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain
and cool for at least 10 min.
10.9 Increase the temperature of the hot water bath to 95 to 100
[deg]C. Remove the Synder column and rinse the flask and its lower joint
into the concentrator tube with 1 to 2 mL of 2-propanol. A 5-mL syringe
is recommended for this operation. Attach a two-ball micro-Snyder column
to the concentrator tube and prewet the column by adding about 0.5 mL of
2-propanol to the top. Place the micro-K-D apparatus on the water bath
so that the concentrator tube is partially immersed in the hot water.
Adjust the vertical position of the apparatus and the water temperature
as required to complete concentration in 5 to 10 min. At the proper rate
of distillation the balls of the column will actively chatter but the
chambers will
[[Page 119]]
not flood. When the apparent volume of liquid reaches 2.5 mL, remove the
K-D apparatus and allow it to drain and cool for at least 10 min. Add an
additional 2 mL of 2-propanol through the top of the micro-Snyder column
and resume concentrating as before. When the apparent volume of liquid
reaches 0.5 mL, remove the K-D apparatus and allow it to drain and cool
for at least 10 min.
10.10 Remove the micro-Snyder column and rinse its lower joint into
the concentrator tube with a minimum amount of 2-propanol. Adjust the
extract volume to 1.0 mL. Stopper the concentrator tube and store
refrigerated at 4 [deg]C if further processing will not be performed
immediately. If the extract will be stored longer than two days, it
should be transferred to a Teflon-sealed screw-cap vial. If the sample
extract requires no further cleanup, proceed with FIDGC analysis
(Section 11). If the sample requires further cleanup, proceed to Section
12.
10.11 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to a 1000-mL graduated
cylinder. Record the sample volume to the nearest 5 mL.
11. Flame Ionization Detector Gas Chromatography
11.1 Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are retention times and MDL
that can be achieved under these conditions. An example of the
separations achieved by this column is shown in Figure 1. Other packed
or capillary (open-tubular) columns, chromatographic conditions, or
detectors may be used if the requirements of Section 8.2 are met.
11.2 Calibrate the system daily as described in Section 7.
11.3 If the internal standard calibration procedure is used, the
internal standard must be added to the sample extract and mixed
thoroughly immediately before injection into the gas chromatograph.
11.4 Inject 2 to 5 [micro]L of the sample extract or standard into
the gas chromatograph using the solvent-flush technique. \11\ Smaller
(1.0 [micro]L) volumes may be injected if automatic devices are
employed. Record the volume injected to the nearest 0.05 [micro]L, and
the resulting peak size in area or peak height units.
11.5 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
may be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
11.6 If the response for a peak exceeds the working range of the
system, dilute the extract and reanalyze.
11.7 If the measurement of the peak response is prevented by the
presence of interferences, an alternative gas chromatographic procedure
is required. Section 12 describes a derivatization and column
chromatographic procedure which has been tested and found to be a
practical means of analyzing phenols in complex extracts.
12. Derivatization and Electron Capture Detector Gas Chromatography
12.1 Pipet a 1.0-mL aliquot of the 2-propanol solution of standard
or sample extract into a glass reaction vial. Add 1.0 mL of derivatizing
reagent (Section 6.11). This amount of reagent is sufficient to
derivatize a solution whose total phenolic content does not exceed 0.3
mg/mL.
12.2 Add about 3 mg of potassium carbonate to the solution and shake
gently.
12.3 Cap the mixture and heat it for 4 h at 80 [deg]C in a hot water
bath.
12.4 Remove the solution from the hot water bath and allow it to
cool.
12.5 Add 10 mL of hexane to the reaction flask and shake vigorously
for 1 min. Add 3.0 mL of distilled, deionized water to the reaction
flask and shake for 2 min. Decant a portion of the organic layer into a
concentrator tube and cap with a glass stopper.
12.6 Place 4.0 g of silica gel into a chromatographic column. Tap
the column to settle the silica gel and add about 2 g of anhydrous
sodium sulfate to the top.
12.7 Preelute the column with 6 mL of hexane. Discard the eluate and
just prior to exposure of the sodium sulfate layer to the air, pipet
onto the column 2.0 mL of the hexane solution (Section 12.5) that
contains the derivatized sample or standard. Elute the column with 10.0
mL of hexane and discard the eluate. Elute the column, in order, with:
10.0 mL of 15% toluene in hexane (Fraction 1); 10.0 mL of 40% toluene in
hexane (Fraction 2); 10.0 mL of 75% toluene in hexane (Fraction 3); and
10.0 mL of 15% 2-propanol in toluene (Fraction 4). All elution mixtures
are prepared on a volume: volume basis. Elution patterns for the
phenolic derivatives are shown in Table 2. Fractions may be combined as
desired, depending upon the specific phenols of interest or level of
interferences.
12.8 Analyze the fractions by ECDGC. Table 2 summarizes the
recommended operating conditions for the gas chromatograph. Included in
this table are retention times and MDL that can be achieved under these
conditions. An example of the separations achieved by this column is
shown in Figure 2.
[[Page 120]]
12.9 Calibrate the system daily with a minimum of three aliquots of
calibration standards, containing each of the phenols of interest that
are derivatized according to Section 7.5.
12.10 Inject 2 to 5 [micro]L of the column fractions into the gas
chromatograph using the solvent-flush technique. Smaller (1.0 [micro]L)
volumes can be injected if automatic devices are employed. Record the
volume injected to the nearest 0.05 [micro]L, and the resulting peak
size in area or peak height units. If the peak response exceeds the
linear range of the system, dilute the extract and reanalyze.
13. Calculations
13.1 Determine the concentration of individual compounds in the
sample analyzed by FIDGC (without derivatization) as indicated below.
13.1.1 If the external standard calibration procedure is used,
calculate the amount of material injected from the peak response using
the calibration curve or calibration factor determined in Section 7.2.2.
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.098
Equation 2
where:
A = Amount of material injected (ng).
Vi = Volume of extract injected ([micro]L).
Vt = Volume of total extract ([micro]L).
Vs = Volume of water extracted (mL).
13.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.099
Equation 3
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Is = Amount of internal standard added to each extract
([micro]g).
Vo = Volume of water extracted (L).
13.2 Determine the concentration of individual compounds in the
sample analyzed by derivatization and ECDGC according to Equation 4.
[GRAPHIC] [TIFF OMITTED] TC15NO91.100
Equation 4
where:
A = Mass of underivatized phenol represented by area of peak in sample
chromatogram, determined from calibration curve in Section
7.5.3 (ng).
Vi = Volume of eluate injected ([micro]L).
Vt = Total volume of column eluate or combined fractions from
which Vi was taken ([micro]L).
Vs = Volume of water extracted in Section 10.10 (mL).
B = Total volume of hexane added in Section 12.5 (mL).
C = Volume of hexane sample solution added to cleanup column in Section
12.7 (mL).
D = Total volume of 2-propanol extract prior to derivatization (mL).
E = Volume of 2-propanol extract carried through derivatization in
Section 12.1 (mL).
13.3 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
14. Method Performance
14.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentrations
listed in Tables 1 and 2 were obtained using reagent water. \12\ Similar
results were achieved using representative wastewaters. The MDL actually
achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
14.2 This method was tested by 20 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
as six concentrations over the range 12 to 450 [micro]g/L. \13\ Single
operator precision, overall precision, and method accuracy were found to
be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships for a flame ionization detector are
presented in Table 4.
References
1. 40 CFR part 136, appendix B.
2. ``Determination of Phenols in Industrial and Municipal
Wastewaters,'' EPA 600/4-84-ABC, National Technical Information Service,
PBXYZ, Springfield, Virginia 22161, November 1984.
3. Kawahara, F. K. ``Microdetermination of Derivatives of Phenols
and Mercaptans by Means of Electron Capture Gas Chromatography,''
Analytical Chemistry, 40, 1009 (1968).
4. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard
Practices for Preparation of Sample Containers and for Preservation of
Organic Constituents,'' American
[[Page 121]]
Society for Testing and Materials, Philadelphia.
5. ``Carcinogens--Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
6. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
7. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
8. Provost, L. P., and Elder, R. S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value 1.22
derived in this report.)
9. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard
Practices for Sampling Water,'' American Society for Testing and
Materials, Philadelphia.
10. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methmds for
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268, March 1979.
11. Burke, J. A. ``Gas Chromatography for Pesticide Residue
Analysis; Some Practical Aspects,'' Journal of the Association of
Official Analytical Chemists, 48, 1037 (1965).
12. ``Development of Detection Limits, EPA Method 604, Phenols,''
Special letter report for EPA Contract 68-03-2625, U.S. Environmental
Protection Agency, Environmental Monitoring and Support Laboratory,
Cincinnati, Ohio 45268.
13. ``EPA Method Study 14 Method 604-Phenols,'' EPA 600/4-84-044,
National Technical Information Service, PB84-196211, Springfield,
Virginia 22161, May 1984.
Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
Method
Retention detection
Parameter time (min) limit
([micro]g/L)
------------------------------------------------------------------------
2-Chlorophenol................................ 1.70 0.31
2-Nitrophenol................................. 2.00 0.45
Phenol........................................ 3.01 0.14
2,4-Dimethylphenol............................ 4.03 0.32
2,4-Dichlorophenol............................ 4.30 0.39
2,4,6-Trichlorophenol......................... 6.05 0.64
4-Chloro-3-methylphenol....................... 7.50 0.36
2,4-Dinitrophenol............................. 10.00 13.0
2-Methyl-4,6-dinitrophenol.................... 10.24 16.0
Pentachlorophenol............................. 12.42 7.4
4-Nitrophenol................................. 24.25 2.8
------------------------------------------------------------------------
Column conditions: Supelcoport (80/100 mesh) coated with 1% SP-1240DA
packed in a 1.8 m long x 2 mm ID glass column with nitrogen carrier
gas at 30 mL/min flow rate. Column temperature was 80 [deg]C at
injection, programmed immediately at 8 [deg]C/min to 150 [deg]C final
temperature. MDL were determined with an FID.
Table 2--Silica Gel Fractionation and Electron Capture Gas Chromatography of PFBB Derivatives
----------------------------------------------------------------------------------------------------------------
Percent recovery by Method
fraction \a\ Retention detection
Parent compound ---------------------------- time limit
(min) ([micro]g/
1 2 3 4 L)
----------------------------------------------------------------------------------------------------------------
2-Chlorophenol............................................... ..... 90 1 ..... 3.3 0.58
2-Nitrophenol................................................ ..... ..... 9 90 9.1 0.77
Phenol....................................................... ..... 90 10 ..... 1.8 2.2
2,4-Dimethylphenol........................................... ..... 95 7 ..... 2.9 0.63
2,4-Dichlorophenol........................................... ..... 95 1 ..... 5.8 0.68
2,4,6-Trichlorophenol........................................ 50 50 ..... ..... 7.0 0.58
4-Chloro-3-methylphenol...................................... ..... 84 14 ..... 4.8 1.8
Pentachlorophenol............................................ 75 20 ..... ..... 28.8 0.59
4-Nitrophenol................................................ ..... ..... 1 90 14.0 0.70
----------------------------------------------------------------------------------------------------------------
Column conditions: Chromosorb W-AW-DMCS (80/100 mesh) coated with 5% OV-17 packed in a 1.8 m long x 2.0 mm ID
glass column with 5% methane/95% argon carrier gas at 30 mL/min flow rate. Column temperature held isothermal
at 200 [deg]C. MDL were determined with an ECD.
\a\ Eluant composition:
Fraction 1--15% toluene in hexane.
Fraction 2--40% toluene in hexane.
Fraction 3--75% toluene in hexane.
Fraction 4--15% 2-propanol in toluene.
[[Page 122]]
Table 3--QC Acceptance Criteria--Method 604
----------------------------------------------------------------------------------------------------------------
Limit for
Test conc. s Range for X Range for
Parameter ([micro]g/ ([micro]g/ ([micro]g/ P, Ps
L) L) L) (percent)
----------------------------------------------------------------------------------------------------------------
4-Chloro-3-methylphenol....................................... 100 16.6 56.7-113.4 49-122
2-Chlorophenol................................................ 100 27.0 54.1-110.2 38-126
2,4-Dichlorophenol............................................ 100 25.1 59.7-103.3 44-119
2,4-Dimethylphenol............................................ 100 33.3 50.4-100.0 24-118
4,6-Dinitro-2-methylphenol.................................... 100 25.0 42.4-123.6 30-136
2,4-Dinitrophenol............................................. 100 36.0 31.7-125.1 12-145
2-Nitrophenol................................................. 100 22.5 56.6-103.8 43-117
4-Nitrophenol................................................. 100 19.0 22.7-100.0 13-110
Pentachlorophenol............................................. 100 32.4 56.7-113.5 36-134
Phenol........................................................ 100 14.1 32.4-100.0 23-108
2,4,6-Trichlorophenol......................................... 100 16.6 60.8-110.4 53-119
----------------------------------------------------------------------------------------------------------------
s--Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X--Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps--Percent recovery measured (Section 8.3.2, Section 8.4.2).
Note: These criteria are based directly upon the method performance data in Table 4. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 4.
Table 4--Method Accuracy and Precision as Functions of Concentration--Method 604
----------------------------------------------------------------------------------------------------------------
Accuracy, as Single Analyst Overall
Parameter recovery, X' precision, sr' precision, S'
([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
4-Chloro-3-methylphenol................................ 0.87C-1.97 0.11X090.21 0.16X + 1.41
2-Chlorophenol......................................... 0.83C-0.84 0.18X + 0.20 0.21X + 0.75
2,4-Dichlorophenol..................................... 0.81C + 0.48 0.17X090.02 0.18X + 0.62
2,4-Dimethylphenol..................................... 0.62C-1.64 0.30X090.89 0.25X + 0.48
4,6-Dinitro-2-methylphenol............................. 0.84C-1.01 0.15X + 1.25 0.19X + 5.85
2,4-Dinitrophenol...................................... 0.80C-1.58 0.27X091.15 0.29X + 4.51
2-Nitrophenol.......................................... 0.81C-0.76 0.15X + 0.44 0.14X + 3.84
4-Nitrophenol.......................................... 0.46C + 0.18 0.17X + 2.43 0.19X + 4.79
Pentachlorophenol...................................... 0.83C + 2.07 0.22X090.58 0.23X + 0.57
Phenol................................................. 0.43C + 0.11 0.20X090.88 0.17X + 0.77
2,4,6-Trichlorophenol.................................. 0.86C-0.40 0.10X + 0.53 0.13X + 2.40
----------------------------------------------------------------------------------------------------------------
X' = Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/L.
sr' = Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S' = Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C = True value for the concentration, in [micro]g/L.
X = Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
[[Page 123]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.012
[[Page 124]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.013
Method 605--Benzidines
1. Scope and Application
1.1 This method covers the determination of certain benzidines. The
following parameters can be determined by this method:
------------------------------------------------------------------------
Parameter Storet No CAS No.
------------------------------------------------------------------------
Benzidine..................................... 39120 92-87-5
3,3'-Dichlorobenzidine........................ 34631 91-94-1
------------------------------------------------------------------------
1.2 This is a high performance liquid chromatography (HPLC) method
applicable to the determination of the compounds listed above in
municipal and industrial discharges as provided under 40 CFR 136.1. When
this method is used to analyze unfamiliar samples for the compounds
above, identifications should be supported by at least one additional
qualitative technique. This method describes electrochemical conditions
at a second potential which can be used to confirm measurements made
with this method. Method 625 provides gas chromatograph/mass
spectrometer (GC/MS) conditions appropriate for the qualitative and
quantitative confirmation of results for the parameters listed above,
using the extract produced by this method.
1.3 The method detection limit (MDL, defined in Section 14.1) \1\
for each parameter is
[[Page 125]]
listed in Table 1. The MDL for a specific wastewater may differ from
those listed, depending upon the nature of the interferences in the
sample matrix.
1.4 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.5 This method is restricted to use by or under the supervision of
analysts experienced in the use of HPLC instrumentation and in the
interpretation of liquid chromatograms. Each analyst must demonstrate
the ability to generate acceptable results with this method using the
procedure described in Section 8.2.
2. Summary of Method
2.1 A measured volume of sample, approximately 1-L, is extracted
with chloroform using liquid-liquid extractions in a separatory funnel.
The chloroform extract is extracted with acid. The acid extract is then
neutralized and extracted with chloroform. The final chloroform extract
is exchanged to methanol while being concentrated using a rotary
evaporator. The extract is mixed with buffer and separated by HPLC. The
benzidine compounds are measured with an electrochemical detector. \2\
2.2 The acid back-extraction acts as a general purpose cleanup to
aid in the elimination of interferences.
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardware that lead to
discrete artifacts and/or elevated baselines in chromatograms. All of
these materials must be routinely demonstrated to be free from
interferences under the conditions of the analysis by running laboratory
reagent blanks as described in Section 8.1.3.
3.1.1 Glassware must be scrupulously cleaned. \3\ Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed by detergent washing with
hot water, and rinses with tap water and distilled water. The glassware
should then be drained dry, and heated in a muffle furnace at 400 [deg]C
for 15 to 30 min. Some thermally stable materials may not be eliminated
by this treatment. Solvent rinses with acetone and pesticide quality
hexane may be substituted for the muffle furnace heating. Volumetric
ware should not be heated in a muffle furnace. After drying and cooling,
glassware should be sealed and stored in a clean environment to prevent
any accumulation of dust or other contaminants. Store inverted or capped
with aluminum foil.
3.1.2 The use of high purity reagents and solvents helps to minimize
interference problems. Purification of solvents by distillation in all-
glass systems may be required.
3.2 Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary
considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled. The
cleanup procedures that are inherent in the extraction step are used to
overcome many of these interferences, but unique samples may require
additional cleanup approaches to achieve the MDL listed in Table 1.
3.3 Some dye plant effluents contain large amounts of components
with retention times closed to benzidine. In these cases, it has been
found useful to reduce the electrode potential in order to eliminate
interferences and still detect benzidine. (See Section 12.7.)
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health harzard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified \4 6\ for
the information of the analyst.
4.2 The following parameters covered by this method have been
tentatively classified as known or suspected, human or mammalian
carcinogens: benzidine and 3,3'-dichlorobenzidine. Primary standards of
these toxic compounds should be prepared in a hood. A NIOSH/MESA
approved toxic gas respirator should be worn when the analyst handles
high concentrations of these toxic compounds.
4.3 Exposure to chloroform should be minimized by performing all
extractions and extract concentrations in a hood or other well-
ventiliated area.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--1-L or 1-qt, amber glass, fitted with a
screw cap lined with Teflon. Foil may be substituted for Teflon if the
sample is not corrosive. If amber bottles are not available, protect
samples from light. The bottle and cap liner must be washed, rinsed with
acetone or methylene
[[Page 126]]
chloride, and dried before use to minimize contamination.
5.1.2 Automatic sampler (optional)--The sampler must incorporate
glass sample containers for the collection of a minimum of 250 mL of
sample. Sample containers must be kept refrigerated at 4 [deg]C and
protected from light during compositing. If the sampler uses a
peristaltic pump, a minimum length of compressible silicone rubber
tubing may be used. Before use, however, the compressible tubing should
be thoroughly rinsed with methanol, followed by repeated rinsings with
distilled water to minimize the potential for contamination of the
sample. An integrating flow meter is required to collect flow
proportional composites.
5.2 Glassware (All specifications are suggested):
5.2.1 Separatory funnels--2000, 1000, and 250-mL, with Teflon
stopcock.
5.2.2 Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
5.2.3 Rotary evaporator.
5.2.4 Flasks--Round bottom, 100-mL, with 24/40 joints.
5.2.5 Centrifuge tubes--Conical, graduated, with Teflon-lined screw
caps.
5.2.6 Pipettes--Pasteur, with bulbs.
5.3 Balance--Analytical, capable of accurately weighing 0.0001 g.
5.4 High performance liquid chromatograph (HPLC)--An analytical
system complete with column supplies, high pressure syringes, detector,
and compatible recorder. A data system is recommended for measuring peak
areas and retention times.
5.4.1 Solvent delivery system--With pulse damper, Altex 110A or
equivalent.
5.4.2 Injection valve (optional)--Waters U6K or equivalent.
5.4.3 Electrochemical detector--Bioanalytical Systems LC-2A with
glassy carbon electrode, or equivalent. This detector has proven
effective in the analysis of wastewaters for the parameters listed in
the scope (Section 1.1), and was used to develop the method performance
statements in Section 14. Guidelines for the use of alternate detectors
are provided in Section 12.1.
5.4.4 Electrode polishing kit--Princeton Applied Research Model 9320
or equivalent.
5.4.5 Column--Lichrosorb RP-2, 5 micron particle diameter, in a 25
cm x 4.6 mm ID stainless steel column. This column was used to develop
the method performance statements in Section 14. Guidelines for the use
of alternate column packings are provided in Section 12.1.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.2 Sodium hydroxide solution (5 N)--Dissolve 20 g of NaOH (ACS) in
reagent water and dilute to 100 mL.
6.3 Sodium hydroxide solution (1 M)--Dissolve 40 g of NaOH (ACS) in
reagent water and dilute to 1 L.
6.4 Sodium thiosulfate--(ACS) Granular.
6.5 Sodium tribasic phosphate (0.4 M)--Dissolve 160 g of trisodium
phosphate decahydrate (ACS) in reagent water and dilute to 1 L.
6.6 Sulfuric acid (1 + 1)--Slowly, add 50 mL of
H2SO4 (ACS, sp. gr. 1.84) to 50 mL of reagent
water.
6.7 Sulfuric acid (1 M)--Slowly, add 58 mL of
H2SO4 (ACS, sp. gr. 1.84) to reagent water and
dilute to 1 L.
6.8 Acetate buffer (0.1 M, pH 4.7)--Dissolve 5.8 mL of glacial
acetic acid (ACS) and 13.6 g of sodium acetate trihydrate (ACS) in
reagent water which has been purified by filtration through a RO-4
Millipore System or equivalent and dilute to 1 L.
6.9 Acetonitrile, chloroform (preserved with 1% ethanol), methanol--
Pesticide quality or equivalent.
6.10 Mobile phase--Place equal volumes of filtered acetonitrile
(Millipore type FH filter or equivalent) and filtered acetate buffer
(Millipore type GS filter or equivalent) in a narrow-mouth, glass
container and mix thoroughly. Prepare fresh weekly. Degas daily by
sonicating under vacuum, by heating and stirring, or by purging with
helium.
6.11 Stock standard solutions (1.00 [micro]g/[micro]L)--Stock
standard solutions may be prepared from pure standard materials or
purchased as certified solutions.
6.11.1 Prepare stock standard solutions by accurately weighing about
0.0100 g of pure material. Dissolve the material in methanol and dilute
to volume in a 10-mL volumetric flask. Larger volumes can be used at the
convenience of the analyst. When compound purity is assayed to be 96% or
greater, the weight can be used without correction to calculate the
concentration of the stock standard. Commercially prepared stock
standards can be used at any concentration if they are certified by the
manufacturer or by an independent source.
6.11.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles. Store at 4 [deg]C and protect from light. Stock
standard solutions should be checked frequently for signs of degradation
or evaporation, especially just prior to preparing calibration standards
from them.
6.11.3 Stock standard solutions must be replaced after six months,
or sooner if comparison with check standards indicates a problem.
6.12 Quality control check sample concentrate--See Section 8.2.1.
[[Page 127]]
7. Calibration
7.1 Establish chromatographic operating conditions equivalent to
those given in Table 1. The HPLC system can be calibrated using the
external standard technique (Section 7.2) or the internal standard
technique (Section 7.3).
7.2 External standard calibration procedure:
7.2.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask and diluting to volume
with mobile phase. One of the external standards should be at a
concentration near, but above, the MDL (Table 1) and the other
concentrations should correspond to the expected range of concentrations
found in real samples or should define the working range of the
detector.
7.2.2 Using syringe injections of 5 to 25 [micro]L or a constant
volume injection loop, analyze each calibration standard according to
Section 12 and tabulate peak height or area responses against the mass
injected. The results can be used to prepare a calibration curve for
each compound. Alternatively, if the ratio of response to amount
injected (calibration factor) is a constant over the working range (<10%
relative standard deviation, RSD), linearity through the origin can be
assumed and the average ratio or calibration factor can be used in place
of a calibration curve.
7.3 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the compounds of interest. The analyst must
further demonstrate that the measurement of the internal standard is not
affected by method or matrix interferences. Because of these
limitations, no internal standard can be suggested that is applicable to
all samples.
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask. To each calibration
standard, add a known constant amount of one or more internal standards,
and dilute to volume with mobile phase. One of the standards should be
at a concentration near, but above, the MDL and the other concentrations
should correspond to the expected range of concentrations found in real
samples or should define the working range of the detector.
7.3.2 Using syringe injections of 5 to 25 [micro]L or a constant
volume injection loop, analyze each calibration standard according to
Section 12 and tabulate peak height or area responses against
concentration for each compound and internal standard. Calculate
response factors (RF) for each compound using Equation 1.
RF = (As)(Cis (Ais)(Cs)
Equation 1
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Cis = Concentration of the internal standard ([micro]g/L).
Cs = Concentration of the parameter to be measured ([micro]g/
L).
If the RF value over the working range is a constant (<10% RSD), the
RF can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.4 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of one or more
calibration standards. If the response for any parameter varies from the
predicted response by more than 15%, a new
calibration curve must be prepared for that compound. If serious loss of
response occurs, polish the electrode and recalibrate.
7.5 Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the reagents.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Sections 10.9, 11.1, and 12.1) to improve the separations or lower the
cost of measurements. Each time such a modification is made to the
method, the analyst is required to repeat the procedure in Section 8.2.
[[Page 128]]
8.1.3 Before processing any samples, the analyst must analyze a
reagent water blank to demonstrate that interferences from the
analytical system and glassware are under control. Each time a set of
samples is extracted or reagents are changed, a reagent water blank must
be processed as a safeguard against laboratory contamination.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing benzidine and/or 3,3'-dichlorobenzidine at a concentration of
50 [micro]g/mL each in methanol. The QC check sample concentrate must be
obtained from the U.S. Environmental Protection Agency, Environmental
Monitoring and Support Laboratory in Cincinnati, Ohio, if available. If
not available from that source, the QC check sample concentrate must be
obtained from another external source. If not available from either
source above, the QC check sample concentrate must be prepared by the
laboratory using stock standards prepared independently from those used
for calibration.
8.2.2 Using a pipet, prepare QC check samples at a concentration of
50 [micro]g/L by adding 1.00 mL of QC check sample concentrate to each
of four 1-L-L aliquots of reagent water.
8.2.3 Analyze the well-mixed QC check samples according to the
method beginning in Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 2. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If any individual s exceeds the precision limit or
any individual X falls outside the range for accuracy, the system
performance is unacceptable for that parameter. Locate and correct the
source of the problem and repeat the test for all parameters of interest
beginning with Section 8.2.2.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at 50 [micro]g/L or 1 to 5 times higher than the
background concentration determined in Section 8.3.2, whichever
concentration would be larger.
8.3.1.3 If it is impractical to determine background levels before
spiking (e.g., maximum holding times will be exceeded), the spike
concentration should be (1) the regulatory concentration limit, if any;
or, if none (2) the larger of either 5 times higher than the expected
background concentration or 50 [micro]g/L.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second sample aliquot with 1.0 mL
of the QC check sample concentrate and analyze it to determine the
concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100(A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 2. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\7\ If spiking was performed at a concentration lower than 50 [micro]g/
L, the analyst must use either the QC acceptance criteria in Table 2, or
optional QC acceptance criteria calculated for the specific spike
concentration. To calculate optional acceptance criteria for the
recovery of a parameter: (1) Calculate accuracy (X') using the equation
in Table 3, substituting
[[Page 129]]
the spike concentration (T) for C; (2) calculate overall precision (S')
using the equation in Table 3, substituting X' for X; (3) calculate the
range for recovery at the spike concentration as (100 X'/T)2.44(100 S'/T)%. \7\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory.
8.4.1 Prepare the QC check standard by adding 1.0 mL of QC check
sample concentrate (Sections 8.2.1 or 8.3.2) to 1 L of reagent water.
The QC check standard needs only to contain the parameters that failed
criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
2. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2sp to P + 2sp.
If P = 90% and sp = 10%, for example, the accuracy interval
is expressed as 70-110%. Update the accuracy assessment for each
parameter on a regular basis (e.g. after each five to ten new accuracy
measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as HPLC with a dissimilar column, gas chromatography, or mass
spectrometer must be used. Whenever possible, the laboratory should
analyze standard reference materials and participate in relevant
performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices \8\ should be followed, except that the bottle must
not be prerinsed with sample before collection. Composite samples should
be collected in refrigerated glass containers in accordance with the
requirements of the program. Automatic sampling equipment must be as
free as possible of Tygon tubing and other potential sources of
contamination.
9.2 All samples must be iced or refrigerated at 4 [deg]C and stored
in the dark from the time of collection until extraction. Both benzidine
and 3,3'-dichlorobenzidine are easily oxidized. Fill the sample bottles
and, if residual chlorine is present, add 80 mg of sodium thiosulfate
per liter of sample and mix well. EPA Methods 330.4 and 330.5 may be
used for measurement of residual chlorine. \9\ Field test kits are
available for this purpose. After mixing, adjust the pH of the sample to
a range of 2 to 7 with sulfuric acid.
9.3 If 1,2-diphenylhydrazine is likely to be present, adjust the pH
of the sample to 4.0 0.2 to prevent rearrangement
to benzidine.
9.4 All samples must be extracted within 7 days of collection.
Extracts may be held up to 7 days before analysis, if stored under an
inert (oxidant free) atmosphere. \2\ The extract should be protected
from light.
10. Sample Extraction
10.1 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Pour the entire sample into a 2-L
separatory funnel. Check the pH of the sample with wide-range pH paper
and adjust to within the range of 6.5 to 7.5 with sodium hydroxide
solution or sulfuric acid.
10.2 Add 100 mL of chloroform to the sample bottle, seal, and shake
30 s to rinse the inner surface. (Caution: Handle chloroform in a well
ventilated area.) Transfer the solvent to the separatory funnel and
extract the sample by shaking the funnel for 2 min with periodic venting
to release excess pressure. Allow the organic layer to separate from the
water phase for a minimum of 10 min. If the emulsion interface between
layers is more than one-third the volume of the solvent layer, the
analyst must employ mechanical techniques to complete the phase
[[Page 130]]
separation. The optimum technique depends upon the sample, but may
include stirring, filtration of the emulsion through glass wool,
centrifugation, or other physical methods. Collect the chloroform
extract in a 250-mL separatory funnel.
10.3 Add a 50-mL volume of chloroform to the sample bottle and
repeat the extraction procedure a second time, combining the extracts in
the separatory funnel. Perform a third extraction in the same manner.
10.4 Separate and discard any aqueous layer remaining in the 250-mL
separatory funnel after combining the organic extracts. Add 25 mL of 1 M
sulfuric acid and extract the sample by shaking the funnel for 2 min.
Transfer the aqueous layer to a 250-mL beaker. Extract with two
additional 25-mL portions of 1 M sulfuric acid and combine the acid
extracts in the beaker.
10.5 Place a stirbar in the 250-mL beaker and stir the acid extract
while carefully adding 5 mL of 0.4 M sodium tribasic phosphate. While
monitoring with a pH meter, neutralize the extract to a pH between 6 and
7 by dropwise addition of 5 N sodium hydroxide solution while stirring
the solution vigorously. Approximately 25 to 30 mL of 5 N sodium
hydroxide solution will be required and it should be added over at least
a 2-min period. Do not allow the sample pH to exceed 8.
10.6 Transfer the neutralized extract into a 250-mL separatory
funnel. Add 30 mL of chloroform and shake the funnel for 2 min. Allow
the phases to separate, and transfer the organic layer to a second 250-
mL separatory funnel.
10.7 Extract the aqueous layer with two additional 20-mL aliquots of
chloroform as before. Combine the extracts in the 250-mL separatory
funnel.
10.8 Add 20 mL of reagent water to the combined organic layers and
shake for 30 s.
10.9 Transfer the organic extract into a 100-mL round bottom flask.
Add 20 mL of methanol and concentrate to 5 mL with a rotary evaporator
at reduced pressure and 35 [deg]C. An aspirator is recommended for use
as the source of vacuum. Chill the receiver with ice. This operation
requires approximately 10 min. Other concentration techniques may be
used if the requirements of Section 8.2 are met.
10.10 Using a 9-in. Pasteur pipette, transfer the extract to a 15-
mL, conical, screw-cap centrifuge tube. Rinse the flask, including the
entire side wall, with 2-mL portions of methanol and combine with the
original extract.
10.11 Carefully concentrate the extract to 0.5 mL using a gentle
stream of nitrogen while heating in a 30 [deg]C water bath. Dilute to 2
mL with methanol, reconcentrate to 1 mL, and dilute to 5 mL with acetate
buffer. Mix the extract thoroughly. Cap the centrifuge tube and store
refrigerated and protected from light if further processing will not be
performed immediately. If the extract will be stored longer than two
days, it should be transferred to a Teflon-sealed screw-cap vial. If the
sample extract requires no further cleanup, proceed with HPLC analysis
(Section 12). If the sample requires further cleanup, proceed to Section
11.
10.12 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to a 1,000-mL graduated
cylinder. Record the sample volume to the nearest 5 mL.
11. Cleanup and Separation
11.1 Cleanup procedures may not be necessary for a relatively clean
sample matrix. If particular circumstances demand the use of a cleanup
procedure, the analyst first must demonstrate that the requirements of
Section 8.2 can be met using the method as revised to incorporate the
cleanup procedure.
12. High Performance Liquid Chromatography
12.1 Table 1 summarizes the recommended operating conditions for the
HPLC. Included in this table are retention times, capacity factors, and
MDL that can be achieved under these conditions. An example of the
separations achieved by this HPLC column is shown in Figure 1. Other
HPLC columns, chromatographic conditions, or detectors may be used if
the requirements of Section 8.2 are met. When the HPLC is idle, it is
advisable to maintain a 0.1 mL/min flow through the column to prolong
column life.
12.2 Calibrate the system daily as described in Section 7.
12.3 If the internal standard calibration procedure is being used,
the internal standard must be added to the sample extract and mixed
thoroughly immediately before injection into the instrument.
12.4 Inject 5 to 25 [micro]L of the sample extract or standard into
the HPLC. If constant volume injection loops are not used, record the
volume injected to the nearest 0.05 [micro]L, and the resulting peak
size in area or peak height units.
12.5 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
12.6 If the response for a peak exceeds the working range of the
system, dilute the extract with mobile phase and reanalyze.
[[Page 131]]
12.7 If the measurement of the peak response for benzidine is
prevented by the presence of interferences, reduce the electrode
potential to + 0.6 V and reanalyze. If the benzidine peak is still
obscured by interferences, further cleanup is required.
13. Calculations
13.1 Determine the concentration of individual compounds in the
sample.
13.1.1 If the external standard calibration procedure is used,
calculate the amount of material injected from the peak response using
the calibration curve or calibration factor determined in Section 7.2.2.
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.101
Equation 2
where:
A = Amount of material injected (ng).
Vi = Volume of extract injected ([micro]L).
Vt = Volume of total extract ([micro]L).
Vs = Volume of water extracted (mL).
13.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.102
Equation 3
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Is = Amount of internal standard added to each extract
([micro]g).
Vo = Volume of water extracted (L).
13.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
14. Method Performance
14.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentrations
listed in Table 1 were obtained using reagent water. \10\ Similar
results were achieved using representative wastewaters. The MDL actually
achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
14.2 This method has been tested for linearity of spike recovery
from reagent water and has been demonstrated to be applicable over the
concentration range from 7 x MDL to 3000 x MDL. \10\
14.3 This method was tested by 17 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
at six concentrations over the range 1.0 to 70 [micro]g/L. \11\ Single
operator precision, overall precision, and method accuracy were found to
be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 3.
References
1. 40 CFR part 136, appendix B.
2. ``Determination of Benzidines in Industrial and Muncipal
Wastewaters,'' EPA 600/4-82-022, National Technical Information Service,
PB82-196320, Springfield, Virginia 22161, April 1982.
3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard
Practices for Preparation of Sample Containers and for Preservation of
Organic Constituents,'' American Society for Testing and Materials,
Philadelphia.
4. ``Carcinogens--Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
6. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value 1.22
derived in this report.)
8. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard
Practices for Sampling Water,'' American Society for Testing and
Materials, Philadelphia.
9. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5
(Spectrophotometric, DPD) for Chlorine Total Residual,'' Methods for
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268, March 1979.
10. ``EPA Method Study 15, Method 605 (Benzidines),'' EPA 600/4-84-
062, National Technical Information Service, PB84-211176, Springfield,
Virginia 22161, June 1984.
11. ``EPA Method Validation Study 15, Method 605 (Benzidines),''
Report for EPA Contract 68-03-2624 (In preparation).
[[Page 132]]
Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
Method
Column detection
Parameter Retention capacity limit
time (min) factor (k') ([micro]g/
L)
------------------------------------------------------------------------
Benzidine........................ 6.1 1.44 0.08
3,3'-Dichlorobenzidine........... 12.1 3.84 0.13
------------------------------------------------------------------------
HPLC Column conditions: Lichrosorb RP-2, 5 micron particle size, in a 25
cm x 4.6 mm ID stainless steel column. Mobile Phase: 0.8 mL/min of 50%
acetonitrile/50% 0.1M pH 4.7 acetate buffer. The MDL were determined
using an electrochemical detector operated at + 0.8 V.
Table 2--QC Acceptance Criteria--Method 605
----------------------------------------------------------------------------------------------------------------
Limit for Range for
Test conc. s X Range for
Parameter ([micro]g/ ([micro]g/ ([micro]g/ P, Ps
L) L) L) (percent)
----------------------------------------------------------------------------------------------------------------
Benzidine........................................................ 50 18.7 9.1-61.0 D-140
3.3'-Dichlorobenzidine........................................... 50 23.6 18.7-50.0 5-128
----------------------------------------------------------------------------------------------------------------
s = Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X = Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps = Percent recovery measured (Section 8.3.2, Section 8.4.2).
D = Detected; result must be greater than zero.
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 3.
Table 3--Method Accuracy and Precision as Functions of Concentration--Method 605
----------------------------------------------------------------------------------------------------------------
Accuracy, as Single analyst Overall
Parameter recovery, precision, sr' precision, S'
X'([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
Benzidine....................................................... 0.70C + 0.06 0.28X + 0.19 0.40X + 0.18
3,3'-Dichlorobenzidine.......................................... 0.66C + 0.23 0.39X-0.05 0.38X + 0.02
----------------------------------------------------------------------------------------------------------------
X' = Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/L.
sr' = Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S' = Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C = True value for the concentration, in [micro]g/L.
X = Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
[[Page 133]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.014
[[Page 134]]
Method 606--Phthalate Ester
1. Scope and Application
1.1 This method covers the determination of certain phthalate
esters. The following parameters can be determined by this method:
------------------------------------------------------------------------
STORET
Parameter No. CAS No.
------------------------------------------------------------------------
Bis(2-ethylhexyl) phthalate........................ 39100 117-81-7
Butyl benzyl phthalate............................. 34292 85-68-7
Di-n-butyl phthalate............................... 39110 84-74-2
Diethyl phthalate.................................. 34336 84-66-2
Dimethyl phthalate................................. 34341 131-11-3
Di-n-octyl phthalate............................... 34596 117-84-0
------------------------------------------------------------------------
1.2 This is a gas chromatographic (GC) method applicable to the
determination of the compounds listed above in municipal and industrial
discharges as provided under 40 CFR 136.1. When this method is used to
analyze unfamiliar samples for any or all of the compounds above,
compound identifications should be supported by at least one additional
qualitative technique. This method describes analytical conditions for a
second gas chromatographic column that can be used to confirm
measurements made with the primary column. Method 625 provides gas
chromatograph/mass spectrometer (GC/MS) conditions appropriate for the
qualitative and quantitative confirmation of results for all of the
parameters listed above, using the extract produced by this method.
1.3 The method detection limit (MDL, defined in Section 14.1) \1\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
1.4 The sample extraction and concentration steps in this method are
essentially the same as in Methods 608, 609, 611, and 612. Thus, a
single sample may be extracted to measure the parameters included in the
scope of each of these methods. When cleanup is required, the
concentration levels must be high enough to permit selecting aliquots,
as necessary, to apply appropriate cleanup procedures. The analyst is
allowed the latitude, under Section 12, to select chromatographic
conditions appropriate for the simultaneous measurement of combinations
of these parameters.
1.5 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.6 This method is restricted to use by or under the supervision of
analysts experienced in the use of a gas chromatograph and in the
interpretation of gas chromatograms. Each analyst must demonstrate the
ability to generate acceptable results with this method using the
procedure described in Section 8.2.
2. Summary of Method
2.1 A measured volume of sample, approximately 1-L, is extracted
with methylene chloride using a separatory funnel. The methylene
chloride extract is dried and exchanged to hexane during concentration
to a volume of 10 mL or less. The extract is separated by gas
chromatography and the phthalate esters are then measured with an
electron capture detector. \2\
2.2 Analysis for phthalates is especially complicated by their
ubiquitous occurrence in the environment. The method provides Florisil
and alumina column cleanup procedures to aid in the elimination of
interferences that may be encountered.
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardware that lead to
discrete artifacts and/or elevated baselines in gas chromatograms. All
of these materials must be routinely demonstrated to be free from
interferences under the conditions of the analysis by running laboratory
reagent blanks as described in Section 8.1.3.
3.1.1 Glassware must be scrupulously cleaned. \3\ Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed by detergent washing with
hot water, and rinses with tap water and distilled water. The glassware
should then be drained dry, and heated in a muffle furnace at 400 [deg]C
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not
be eliminated by this treatment. Solvent rinses with acetone and
pesticide quality hexane may be substituted for the muffle furnace
heating. Thorough rinsing with such solvents usually eliminates PCB
interference. Volumetric ware should not be heated in a muffle furnace.
After drying and cooling, glassware should be sealed and stored in a
clean environment to prevent any accumulation of dust or other
contaminants. Store inverted or capped with aluminum foil.
3.1.2 The use of high purity reagents and solvents helps to minimize
interference problems. Purification of solvents by distillation in all-
glass systems may be required.
3.2 Phthalate esters are contaminants in many products commonly
found in the laboratory. It is particularly important to avoid the use
of plastics because phthalates are commonly used as plasticizers and are
easily extracted from plastic materials. Serious phthalate contamination
can result at any time, if consistent quality control is not practiced.
Great care must be experienced to prevent such contamination. Exhaustive
cleanup of reagents and glassware may be required to eliminate
background phthalate contamination. \4 5\
[[Page 135]]
3.3 Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary
considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled. The
cleanup procedures in Section 11 can be used to overcome many of these
interferences, but unique samples may require additional cleanup
approaches to achieve the MDL listed in Table 1.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified \6 8\ for
the information of the analyst.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--1-L or 1-qt, amber glass, fitted with a
screw cap lined with Teflon. Foil may be substituted for Teflon if the
sample is not corrosive. If amber bottles are not available, protect
samples from light. The bottle and cap liner must be washed, rinsed with
acetone or methylene chloride, and dried before use to minimize
contamination.
5.1.2 Automatic sampler (optional)--The sampler must incorporate
glass sample containers for the collection of a minimum of 250 mL of
sample. Sample containers must be kept refrigerated at 4 [deg]C and
protected from light during compositing. If the sampler uses a
peristaltic pump, a minimum length of compressible silicone rubber
tubing may be used. Before use, however, the compressible tubing should
be thoroughly rinsed with methanol, followed by repeated rinsings with
distilled water to minimize the potential for contamination of the
sample. An integrating flow meter is required to collect flow
proportional composites.
5.2 Glassware (All specifications are suggested. Catalog numbers are
included for illustration only).
5.2.1 Separatory funnel--2-L, with Teflon stopcock.
5.2.2 Drying column--Chromatographic column, approximately 400 mm
long x 19 mm ID, with coarse frit filter disc.
5.2.3 Chromatographic column--300 mm long x 10 mm ID, with Teflon
stopcock and coarse frit filter disc at bottom (Kontes K-420540-0213 or
equivalent).
5.2.4 Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes K-
570050-1025 or equivalent). Calibration must be checked at the volumes
employed in the test. Ground glass stopper is used to prevent
evaporation of extracts.
5.2.5 Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
5.2.6 Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
5.2.7 Snyder column, Kuderna-Danish--Two-ball micro (Kontes K-
569001-0219 or equivalent).
5.2.8 Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
5.3 Boiling chips--Approximately 10/40 mesh. Heat to 400 [deg]C for
30 min or Soxhlet extract with methylene chloride.
5.4 Water bath--Heated, with concentric ring cover, capable of
temperature control (2 [deg]C). The bath should be
used in a hood.
5.5 Balance--Analytical, capable of accurately weighing 0.0001 g.
5.6 Gas chromatograph--An analytical system complete with gas
chromatograph suitable for on-column injection and all required
accessories including syringes, analytical columns, gases, detector, and
strip-chart recorder. A data system is recommended for measuring peak
areas.
5.6.1 Column 1--1.8 m long x 4 mm ID glass, packed with 1.5% SP-
2250/1.95% SP-2401 Supelcoport (100/120 mesh) or equivalent. This column
was used to develop the method performance statemelts in Section 14.
Guidelines for the use of alternate column packings are provided in
Section 12.1.
5.6.2 Column 2--1.8 m long x 4 mm ID glass, packed with 3% OV-1 on
Supelcoport (100/120 mesh) or equivalent.
5.6.3 Detector--Electron capture detector. This detector has proven
effective in the analysis of wastewaters for the parameters listed in
the scope (Section 1.1), and was used to develop the method performance
statements in Section 14. Guidelines for the use of alternate detectors
are provided in Section 12.1.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.2 Acetone, hexane, isooctane, methylene chloride, methanol--
Pesticide quality or equivalent.
6.3 Ethyl ether--nanograde, redistilled in glass if necessary.
6.3.1 Ethyl ether must be shown to be free of peroxides before it is
used as indicated by
[[Page 136]]
EM Laboratories Quant test strips. (Available from Scientific Products
Co., Cat. No. P1126-8, and other suppliers.)
6.3.2 Procedures recommended for removal of peroxides are provided
with the test strips. After cleanup, 20 mL of ethyl alcohol preservative
must be added to each liter of ether.
6.4 Sodium sulfate--(ACS) Granular, anhydrous. Several levels of
purification may be required in order to reduce background phthalate
levels to an acceptable level: 1) Heat 4 h at 400 [deg]C in a shallow
tray, 2) Heat 16 h at 450 to 500 [deg]C in a shallow tray, 3) Soxhlet
extract with methylene chloride for 48 h.
6.5 Florisil--PR grade (60/100 mesh). Purchase activated at 1250
[deg]F and store in the dark in glass containers with ground glass
stoppers or foil-lined screw caps. To prepare for use, place 100 g of
Florisil into a 500-mL beaker and heat for approximately 16 h at 40
[deg]C. After heating transfer to a 500-mL reagent bottle. Tightly seal
and cool to room temperature. When cool add 3 mL of reagent water. Mix
thoroughly by shaking or rolling for 10 min and let it stand for at
least 2 h. Keep the bottle sealed tightly.
6.6 Alumina--Neutral activity Super I, W200 series (ICN Life
Sciences Group, No. 404583). To prepare for use, place 100 g of alumina
into a 500-mL beaker and heat for approximately 16 h at 400 [deg]C.
After heating transfer to a 500-mL reagent bottle. Tightly seal and cool
to room temperature. When cool add 3 mL of reagent water. Mix thoroughly
by shaking or rolling for 10 min and let it stand for at least 2 h. Keep
the bottle sealed tightly.
6.7 Stock standard solutions (1.00 [micro]g/[micro]L)--Stock
standard solutions can be prepared from pure standard materials or
purchased as certified solutions.
6.7.1 Prepare stock standard solutions by accurately weighing about
0.0100 g of pure material. Dissolve the material in isooctane and dilute
to volume in a 10-mL volumetric flask. Larger volumes can be used at the
convenience of the analyst. When compound purity is assayed to be 96% or
greater, the weight can be used without correction to calculate the
concentration of the stock standard. Commercially prepared stock
standards can be used at any concentration if they are certified by the
manufacturer or by an independent source.
6.7.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles. Store at 4 [deg]C and protect from light. Stock
standard solutions should be checked frequently for signs of degradation
or evaporation, especially just prior to preparing calibration standards
from them.
6.7.3 Stock standard solutions must be replaced after six months, or
sooner if comparison with check standards indicates a problem.
6.8 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Establish gas chromatograph operating conditions equivalent to
those given in Table 1. The gas chromatographic system can be calibrated
using the external standard technique (Section 7.2) or the internal
standard technique (Section 7.3).
7.2 External standard calibration procedure:
7.2.1 Prepared calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask and diluting to volume
with isooctane. One of the external standards should be at a
concentration near, but above, the MDL (Table 1) and the other
concentrations should correspond to the expected range of concentrations
found in real samples or should define the working range of the
detector.
7.2.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against the mass injected. The results can be used to prepare
a calibration curve for each compound. Alternatively, if the ratio of
response to amount injected (calibration factor) is a constant over the
working range (<10% relative standard deviation, RSD), linearity through
the origin can be assumed and the average ratio or calibration factor
can be used in place of a calibration curve.
7.3 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the compounds of interest. The analyst must
further demonstrate that the measurement of the internal standard is not
affected by method or matrix interferences. Because of these
limitations, no internal standard can be suggested that is applicable to
all samples.
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flash. To each calibration
standard, add a known constant amount of one or more internal standards,
and dilute to volume with isooctane. One of the standards should be at a
concentration near, but above, the MDL and the other concentrations
should correspond to the expected range of concentrations found in real
samples or should define the working range of the detector.
[[Page 137]]
7.3.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against concentration for each compound and internal standard.
Calculate response factors (RF) for each compound using Equation 1.
RF = (As)(Cis (Ais)(Cs)
Equation 1
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Cis = Concentration of the internal standard ([micro]g/L).
Cs = Concentration of the parameter to be measured ([micro]g/
L).
If the RF value over the working range is a constant (<10% RSD), the
RF can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.4 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of one or more
calibration standards. If the response for any parameter varies from the
predicted response by more than 15%, a new
calibration curve must be prepared for that compound.
7.5 Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the reagents.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Sections 10.4, 11.1, and 12.1) to improve the separations or lower the
cost of measurements. Each time such a modification is made to the
method, the analyst is required to repeat the procedure in Section 8.2.
8.1.3 Before processing any samples, the analyst must analyze a
reagent water blank to demonstrate that interferences from the
analytical system and glassware are under control. Each time a set of
samples is extracted or reagents are changed, a reagent water blank must
be processed as a safeguard against laboratory contamination.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality contrml (QC) check sample concentrate is required
containing each parameter of interest at the following concentrations in
acetone: butyl benzyl phthalate, 10 [micro]g/mL; bis(2-ethylhexyl)
phthalate, 50 [micro]g/mL; di-n-octyl phthalate, 50 [micro]g/mL; any
other phthlate, 25 [micro]g/mL. The QC check sample concentrate must be
obtained from the U.S. Environmental Protection Agancy, Environmental
Monitoring and Support Laboratory in Cincinnati, Ohio, if available. If
not available from that source, the QC check sample concentrate must be
obtained from another external source. If not available from either
source above, the QC check sample concentrate must be prepared by the
laboratory using stock standards prepared independently from those used
for calibration.
8.2.2 Using a pipet, prepare QC check samples at the test
concentrations shown in Table 2 by adding 1.00 mL of QC check sample
concentrate to each of four 1-L aliquots of reagent water.
8.2.3 Analyze the well-mixed QC check samples according to the
method beginning in Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively,
[[Page 138]]
found in Table 2. If s and X for all parameters of interest meet the
acceptance criteria, the system performance is acceptable and analysis
of actual samples can begin. If any individual s exceeds the precision
limit or any individual X falls outside the range for accuracy, the
system performance is unacceptable for that parameter. Locate and
correct the source of the problem and repeat the test for all parameters
of interest beginning with Section 8.2.2.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at the test concentration in Section 8.2.2 or 1 to 5
times higher than the background concentration determined in Section
8.3.2, whichever concentration would be larger.
8.3.1.3 If it is impractical to determine background levels before
spiking (e.g., maximum holding times will be exceeded), the spike
concentration should be (1) the regulatory concentration limit, if any;
or, if none (2) the larger of either 5 times higher than the expected
background concentration or the test concentration in Section 8.2.2.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second sample aliquot with 1.0 mL
of the QC check sample concentrate and analyze it to determine the
concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100(A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 2. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\9\ If spiking was performed at a concentration lower than the test
concentration in Section 8.2.2, the analyst must use either the QC
acceptance criteria in Table 2, or optional QC acceptance criteria
calculated for the specific spike concentration. To calculate optional
acceptance criteria for the recovery of a parameter: (1) Calculate
accuracy (X') using the equation in Table 3, substituting the spike
concentration (T) for C; (2) calculate overall precision (S') using the
equation in Table 3, substituting X' for X; (3) calculate the range for
recovery at the spike concentration as (100 X'/T)2.44(100 S'/T)%. \9\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory.
8.4.1 Prepare the QC check standard by adding 1.0 mL of QC check
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The
QC check standard needs only to contain the parameters that failed
criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
2. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2sp to P + 2sp.
If P = 90% and sp = 10%, for example, the accuracy interval
is expressed as 70-110%. Update the accuracy assessment for each
parameter on a regular basis (e.g. after each five to ten new accuracy
measurements).
[[Page 139]]
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as gas chromatography with a dissimilar column, specific element
detector, or mass spectrometer must be used. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevant performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices \10\ should be followed, except that the bottle must
not be prerinsed with sample before collection. Composite samples should
be collected in refrigerated glass containers in accordance with the
requirements of the program. Automatic sampling equipment must be as
free as possible of Tygon tubing and other potential sources of
contamination.
9.2 All samples must be iced or refrigerated at 4 [deg]C from the
time of collection until extraction.
9.3 All samples must be extracted within 7 days of collection and
completely analyzed within 40 days of extraction. \2\
10. Sample Extraction
10.1 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Pour the entire sample into a 2-L
separatory funnel.
10.2 Add 60 mL of methylene chloride to the sample bottle, seal, and
shake 30 s to rinse the inner surface. Transfer the solvent to the
separatory funnel and extract the sample by shaking the funnel for 2
min. with periodic venting to release excess pressure. Allow the organic
layer to separate from the water phase for a minimum of 10 min. If the
emulsion interface between layers is more than one-third the volume of
the solvent layer, the analyst must employ mechanical techniques to
complete the phrase separation. The optimum technique depends upon the
sample, but may include stirring, filtration of the emulsion through
glass wool, centrifugation, or other physical methods. Collect the
methylene chloride extract in a 250-mL Erlenmeyer flask.
10.3 Add a second 60-mL volume of methylene chloride to the sample
bottle and repeat the extraction procedure a second time, combining the
extracts in the Erlenmeyer flask. Perform a third extraction in the same
manner.
10.4 Assemble a Kuderna-Danish (K-D) concentrator by attaching a 10-
mL concentrator tube to a 500-mL evaporative flask. Other concentrator
devices or techniques may be used in place of the K-D concentrator if
the requirements of Section 8.2 are met.
10.5 Pour the combined extract through a solvent-rinsed drying
column containing about 10 cm of anhydrous sodium sulfate, and collect
the extract in the K-D concentrator. Rinse the Erlenmeyer flask and
column with 20 to 30 mL of methylene chloride to complete the
quantitative transfer.
10.6 Add one or two clean boiling chips to the evaporative flask and
attach a three-ball Snyder column. Prewet the Snyder column by adding
about 1 mL of methylene chloride to the top. Place the K-D apparatus on
a hot water bath (60 to 65 [deg]C) so that the concentrator tube is
partially immersed in the hot water, and the entire lower rounded
surface of the flask is bathed with hot vapor. Adjust the vertical
position of the apparatus and the water temperature as required to
complete the concentration in 15 to 20 min. At the proper rate of
distillation the balls of the column will actively chatter but the
chambers will not flood with condensed solvent. When the apparent volume
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain
and cool for at least 10 min.
10.7 Increase the temperature of the hot water bath to about 80
[deg]C. Momentarily remove the Snyder column, add 50 mL of hexane and a
new boiling chip, and reattach the Snyder column. Concentrate the
extract as in Section 10.6, except use hexane to prewet the column. The
elapsed time of concentration should be 5 to 10 min.
10.8 Remove the Snyder column and rinse the flask and its lower
joint into the concentrator tube with 1 to 2 mL of hexane. A 5-mL
syringe is recommended for this operation. Adjust the extract volume to
10 mL. Stopper the concentrator tube and store refrigerated if further
processing will not be performed immediately. If the extract will be
stored longer than two days, it should be transferred to a Teflon-sealed
screw-cap vial. If the sample extract requires no further cleanup,
proceed with gas chromatographic analysis (Section 12). If the sample
requires further cleanup, proceed to Section 11.
10.9 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to a 1000-mL graduated
cylinder. Record the sample volume to the nearest 5 mL.
11. Cleanup and Separation
11. Cleanup procedures may not be necessary for a relatively clean
sample matrix. If particular circumstances demand the use of a cleanup
procedure, the analyst may use either procedure below or any other
appropriate procedure. However, the analyst first must demonstrate that
the requirements of
[[Page 140]]
Section 8.2 can be met using the method as revised to incorporate the
cleanup procedure.
11.2 If the entire extract is to be cleaned up by one of the
following procedures, it must be concentrated to 2.0 mL. To the
concentrator tube in Section 10.8, add a clean boiling chip and attach a
two-ball micro-Snyder column. Prewet the column by adding about 0.5 mL
of hexane to the top. Place the micro-K-D apparatus on a hot water bath
(80 [deg]C) so that the concentrator tube is partially immersed in the
hot water. Adjust the vertical position of the apparatus and the water
temperature as required to complete the concentration in 5 to 10 min. At
the proper rate of distillation the balls of the column will actively
chatter but the chambers will not flood. When the apparent volume of
liquid reaches about 0.5 mL, remove the K-D apparatus and allow it to
drain and cool for at least 10 min. Remove the micro-Snyder column and
rinse its lower joint into the concentrator tube with 0.2 mL of hexane.
Adjust the final volume to 2.0 mL and proceed with one of the following
cleanup procedures.
11.3 Florisil column cleanup for phthalate esters:
11.3.1 Place 10 g of Florisil into a chromatographic column. Tap the
column to settle the Florisil and add 1 cm of anhydrous sodium sulfate
to the top.
11.3.2 Preelute the column with 40 mL of hexane. The rate for all
elutions should be about 2 mL/min. Discard the eluate and just prior to
exposure of the sodium sulfate layer to the air, quantitatively transfer
the 2-mL sample extract onto the column using an additional 2 mL of
hexane to complete the transfer. Just prior to exposure of the sodium
sulfate layer to the air, add 40 mL of hexane and continue the elution
of the column. Discard this hexane eluate.
11.3.3 Next, elute the column with 100 mL of 20% ethyl ether in
hexane (V/V) into a 500-mL K-D flask equipped with a 10-mL concentrator
tube. Concentrate the collected fraction as in Section 10.6. No solvent
exchange is necessary. Adjust the volume of the cleaned up extract to 10
mL in the concentrator tube and analyze by gas chromatography (Section
12).
11.4 Alumina column cleanup for phthalate esters:
11.4.1 Place 10 g of alumina into a chromatographic column. Tap the
column to settle the alumina and add 1 cm of anhydrous sodium sulfate to
the top.
11.4.2 Preelute the column with 40 mL of hexane. The rate for all
elutions should be about 2 mL/min. Discard the eluate and just prior to
exposure of the sodium sulfate layer to the air, quantitatively transfer
the 2-mL sample extract onto the column using an additional 2 mL of
hexane to complete the transfer. Just prior to exposure of the sodium
sulfate layer to the air, add 35 mL of hexane and continue the elution
of the column. Discard this hexane eluate.
11.4.3 Next, elute the column with 140 mL of 20% ethyl ether in
hexane (V/V) into a 500-mL K-D flask equipped with a 10-mL concentrator
type. Concentrate the collected fraction as in Section 10.6. No solvent
exchange is necessary. Adjust the volume of the cleaned up extract to 10
mL in the concentrator tube and analyze by gas chromatography (Section
12).
12. Gas Chromatography
12.1 Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are retention times and MDL
that can be achieved under these conditions. Examples of the separations
achieved by Column 1 are shown in Figures 1 and 2. Other packed or
capillary (open-tubular) columns, chromatographic conditions, or
detectors may be used if the requirements of Section 8.2 are met.
12.2 Calibrate the system daily as described in Section 7.
12.3 If the internal standard calibration procedure is being used,
the internal staldard must be added to the sample extract and mixed
thoroughly immediately before injection into the gas chromatograph.
12.4 Inject 2 to 5 [micro]L of the sample extract or standard into
the gas-chromatograph using the solvent-flush technique. \11\ Smaller
(1.0 [micro]L) volumes may be injected if automatic devices are
employed. Record the volume injected to the nearest 0.05 [micro]L, and
the resulting peak size in area or peak height units.
12.5 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
12.6 If the response for a peak exceeds the working range of the
system, dilute the extract and reanalyze.
12.7 If the measurement of the peak response is prevented by the
presence of interferences, further cleanup is required.
13. Calculations
13.1 Determine the concentration of individual compounds in the
sample.
13.1.1 If the external standard calibration procedure is used,
calculate the amount of material injected from the peak response using
the calibration curve or calibration
[[Page 141]]
factor determined in Section 7.2.2. The concentration in the sample can
be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.103
Equation 2
where:
A = Amount of material injected (ng).
Vi = Volume of extract injected ([micro]L).
Vt = Volume of total extract ([micro]L).
Vs = Volume of water extracted (mL).
13.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.104
Equation 3
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Is = Amount of internal standard added to each extract
([micro]g).
Vo = Volume of water extracted (L).
13.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
14. Method Performance
14.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentrations
listed in Table 1 were obtained using reagent water. \12\ Similar
results were achieved using representative wastewaters. The MDL actually
achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
14.2 This method has been tested for linearity of spike recovery
from reagent water and has been demonstrated to be applicable over the
concentration range from 5 x MDL to 1000 x MDL with the following
exceptions: dimethyl and diethyl phthalate recoveries at 1000 x MDL were
low (70%); bis-2-ethylhexyl and di-n-octyl phthalate recoveries at 5 x
MDL were low (60%). \12\
14.3 This method was tested by 16 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
at six concentrations over the range 0.7 to 106 [micro]g/L. \13\ Single
operator precision, overall precision, and method accuracy were found to
be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 3.
References
1. 40 CFR part 136, appendix B.
2. ``Determination of Phthalates in Industrial and Muncipal
Wastewaters,'' EPA 600/4-81-063, National Technical Information Service,
PB81-232167, Springfield, Virginia 22161, July 1981.
3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard
Practices for Preparation of Sample Containers and for Preservation of
Organic Constituents,'' American Society for Testing and Materials,
Philadelphia.
4. Giam, C.S., Chan, H.S., and Nef, G.S. ``Sensitive Method for
Determination of Phthalate Ester Plasticizers in Open-Ocean Biota
Samples,'' Analytical Chemistry, 47, 2225 (1975).
5. Giam, C.S., and Chan, H.S. ``Control of Blanks in the Analysis of
Phthalates in Air and Ocean Biota Samples,'' U.S. National Bureau of
Standards, Special Publication 442, pp. 701-708, 1976.
6. ``Carcinogens--Working with Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
7. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
8. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
9. Provost L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value 1.22
derived in this report.)
10. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard
Practices for Sampling Water,'' American Society for Testing and
Materials, Philadelphia.
11. Burke, J.A. ``Gas Chromatography for Pesticide Residue Analysis;
Some Practical Aspects,'' Journal of the Association of Official
Analytical Chemists, 48, 1037 (1965).
12. ``Method Detection Limit and Analytical Curve Studies, EPA
Methods 606, 607, and 608,'' Special letter report for EPA Contract 68-
03-2606, U.S. Environmental Protection Agency, Environmental Monitoring
and Support Laboratory, Cincinnati, Ohio 45268, June 1980.
13. ``EPA Method Study 16 Method 606 (Phthalate Esters),'' EPA 600/
4-84-056, National Technical Information Service, PB84-211275,
Springfield, Virginia 22161, June 1984.
[[Page 142]]
Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
Retention time (min) Method
---------------------------- detection
Parameter limit
Column 1 Column 2 ([micro]g/L)
------------------------------------------------------------------------
Dimethyl phthalate............ 2.03 0.95 0.29
Diethyl phthalate............. 2.82 1.27 0.49
Di-n-butyl phthalate.......... 8.65 3.50 0.36
Butyl benzyl phthalate........ \a\ 6.94 \a\ 5.11 0.34
Bis(2-ethylhexyl) phthalate... \a\ 8.92 \a\ 10.5 2.0
Di-n-octyl phthalate.......... \a\ 16.2 \a\ 18.0 3.0
------------------------------------------------------------------------
Column 1 conditions: Supelcoport (100/120 mesh) coated with 1.5% SP-2250/
1.95% SP-2401 packed in a 1.8 m long x 4 mm ID glass column with 5%
methane/95% argon carrier gas at 60 mL/min flow rate. Column
temperature held isothermal at 180 [deg]C, except where otherwise
indicated.
Column 2 conditions: Supelcoport (100/120 mesh) coated with 3% OV-1
packed in a 1.8 m long x 4 mm ID glass column with 5% methane/95%
argon carrier gas at 60 mL/min flow rate. Column temperature held
isothermal at 200 [deg]C, except where otherwise indicated.
\a\ 220 [deg]C column temperature.
Table 2--QC Acceptance Criteria--Method 606
----------------------------------------------------------------------------------------------------------------
Limit for Range for
Test conc. s X Range for
Parameter ([micro]g/ ([micro]g/ ([micro]g/ P, Ps
L) L) L) (percent)
----------------------------------------------------------------------------------------------------------------
Bis(2-ethylhexyl) phthalate...................................... 50 38.4 1.2-55.9 D-158
Butyl benzyl phthalate........................................... 10 4.2 5.7-11.0 30-136
Di-n-butyl phthalate............................................. 25 8.9 10.3-29.6 23-136
Diethyl phthalate................................................ 25 9.0 1.9-33.4 D-149
Dimethyl phathalate.............................................. 25 9.5 1.3-35.5 D-156
Di-n-octyl phthalate............................................. 50 13.4 D-50.0 D-114
----------------------------------------------------------------------------------------------------------------
s = Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X = Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps = Percent recovery measured (Section 8.3.2, Section 8.4.2).
D = Detected; result must be greater than zero.
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 3.
Table 3--Method Accuracy and Precision as Functions of Concentration--Method 606
----------------------------------------------------------------------------------------------------------------
Accuracy, as Single analyst Overall
Parameter recovery, X' precision, sr' precision, S'
([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
Bis(2-ethylhexyl) phthalate..................................... 0.53C + 2.02 0.80X-2.54 0.73X-0.17
Butyl benzyl phthalate.......................................... 0.82C + 0.13 0.26X + 0.04 0.25X + 0.07
Di-n-butyl phthalate............................................ 0.79C + 0.17 0.23X + 0.20 0.29X + 0.06
Diethyl phthalate............................................... 0.70C + 0.13 0.27X + 0.05 0.45X + 0.11
Dimethyl phthalate.............................................. 0.73C + 0.17 0.26X + 0.14 0.44X + 0.31
Di-n-octyl phthalate............................................ 0.35C-0.71 0.38X + 0.71 0.62X + 0.34
----------------------------------------------------------------------------------------------------------------
X' = Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/L.
sr' = Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S' = Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C = True value for the concentration, in [micro]g/L.
X = Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
[[Page 143]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.015
[[Page 144]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.016
[[Page 145]]
Method 607--Nitrosamines
1. Scope and Application
1.1 This method covers the determination of certain nitrosamines.
The following parameters can be determined by this method:
------------------------------------------------------------------------
Parameter Storet No. CAS No.
------------------------------------------------------------------------
N-Nitrosodimethylamine........................ 34438 62-75-9
N-Nitrosodiphenylamine........................ 34433 86-30-6
N-Nitrosodi-n-propylamine..................... 34428 621-64-7
------------------------------------------------------------------------
1.2 This is a gas chromatographic (GC) method applicable to the
determination of the parameters listed above in municipal and industrial
discharges as provided under 40 CFR 136.1. When this method is used to
analyze unfamiliar samples for any or all of the compmunds above,
compound identifications should be supported by at least one additional
qualitative technique. This method describes analytical conditimns for a
second gas chromatographic column that can be used to confirm
measurements made with the primary column. Method 625 provides gas
chromatograph/mass spectrometer (GC/MS) conditions appropriate for the
qualitative and quantitative confirmation of results for N-nitrosodi-n-
propylamine. In order to confirm the presence of N-nitrosodiphenylamine,
the cleanup procedure specified in Section 11.3 or 11.4 must be used. In
order to confirm the presence of N-nitrosodimethylamine by GC/MS, Column
1 of this method must be substituted for the column recommended in
Method 625. Confirmation of these parameters using GC-high resolution
mass spectrometry or a Thermal Energy Analyzer is also recommended. \1
2\
1.3 The method detection limit (MDL, defined in Section 14.1) \3\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
1.4 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.5 This method is restricted to use by or under the supervision of
analysts experienced in the use of a gas chromatograph and in the
interpretation of gas chromatograms. Each analyst must demonstrate the
ability to generate acceptable results with this method using the
procedure described in Section 8.2.
2. Summary of Method
2.1 A measured volume of sample, approximately 1-L, is extracted
with methylene chloride using a separatory funnel. The methylene
chloride extract is washed with dilute hydrochloric acid to remove free
amines, dried, and concentrated to a volume of 10 mL or less. After the
extract has been exchanged to methanol, it is separated by gas
chromatography and the parameters are then measured with a nitrogen-
phosphorus detector. \4\
2.2 The method provides Florisil and alumina column cleanup
procedures to separate diphenylamine from the nitrosamines and to aid in
the elimination of interferences that may be encountered.
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardware that lead to
discrete artifacts and/or elevated baselines in gas chromatograms. All
of these materials must be routinely demonstrated to be free from
interferences under the conditions of the analysis by running laboratory
reagent blanks as described in Section 8.1.3.
3.1.1 Glassware must be scrupulously cleaned. \5\ Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed by detergent washing with
hot water, and rinses with tap water and distilled water. The glassware
should then be drained dry, and heated in a muffle furnace at 400 [deg]C
for 15 to 30 min. Solvent rinses with acetone and pesticide quality
hexane may be substituted for the muffle furnace heating. Volumetric
ware should not be heated in a muffle furnace. After drying and cooling,
glassware should be sealed and stored in a clean environment to prevent
any accumulation of dust or other contaminants. Store inverted or capped
with aluminum foil.
3.1.2 The use of high purity reagents and solvents helps to minimize
interference problems. Purification of solvents by distillation in all-
glass systems may be required.
3.2 Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary
considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled. The
cleanup procedures in Section 11 can be used to overcome many of these
interferences, but unique samples may require additional cleanup
approaches to achieve the MDL listed in Table 1.
3.3 N-Nitrosodiphenylamine is reported \6-9\ to undergo
transnitrosation reactions. Care must be exercised in the heating or
concentrating of solutions containing this compound in the presence of
reactive amines.
3.4 The sensitive and selective Thermal Energy Analyzer and the
reductive Hall detector may be used in place of the nitrogen-phosphorus
detector when interferences are encountered. The Thermal Energy Analyzer
offers the highest selectivity of the non-MS detectors.
[[Page 146]]
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified \10-12\ for
the information of the analyst.
4.2 These nitrosamines are known carcinogens, \13-17\ therefore,
utmost care must be exercised in the handling of these materials.
Nitrosamine reference standards and standard solutions should be handled
and prepared in a ventilated glove box within a properly ventilated
room.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--1-L or 1-qt, amber glass, fitted with a
screw cap lined with Teflon. Foil may be substituted for Teflon if the
sample is not corrosive. If amber bottles are not available, protect
samples from light. The bottle and cap liner must be washed, rinsed with
acetone or methylene chloride, and dried before use to minimize
contamination.
5.1.2 Automatic sampler (optional)--The sampler must incorporate
glass sample containers for the collection of a minimum of 250 mL of
sample. Sample containers must be kept refrigerated at 4 [deg]C and
protected from light during compositing. If the sampler uses a
peristaltic pump, a minimum length of compressible silicone rubber
tubing may be used. Before use, however, the compressible tubing should
be thoroughly rinsed with methanol, followed by repeated rinsings with
distilled water to minimize the potential for contamination of the
sample. An integrating flowmeter is required to collect flow
proportional composites.
5.2 Glassware (All specifications are suggested. Catalog numbers are
included for illustration only.):
5.2.1 Separatory funnels--2-L and 250-mL, with Teflon stopcock.
5.2.2 Drying column--Chromatographic column, approximately 400 mm
long x 19 mm ID, with coarse frit filter disc.
5.2.3 Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes K-
570050-1025 or equivalent). Calibration must be checked at the volumes
employed in the test. Ground glass stopper is used to prevent
evaporation of extracts.
5.2.4 Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
5.2.5 Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
5.2.6 Snyder column, Kuderna-Danish--Two-ball micro (Kontes K-
569001-0219 or equivalent).
5.2.7 Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
5.2.8 Chromatographic column--Approximately 400 mm long x 22 mm ID,
with Teflon stopcock and coarse frit filter disc at bottom (Kontes K-
420540-0234 or equivalent), for use in Florisil column cleanup
procedure.
5.2.9 Chromatographic column--Approximately 300 mm long x 10 mm ID,
with Teflon stopcock and coarse frit filter disc at bottom (Kontes K-
420540-0213 or equivalent), for use in alumina column cleanup procedure.
5.3 Boiling chips--Approximately 10/40 mesh. Heat to 400 [deg]C for
30 min or Soxhlet extract with methylene chloride.
5.4 Water bath--Heated, with concentric ring cover, capable of
temperature control (2 [deg]C). The bath should be
used in a hood.
5.5 Balance--Analytical, capable of accurately weighing 0.0001 g.
5.6 Gas chromatograph--An analytical system complete with gas
chromatograph suitable for on-column injection and all required
accessories including syringes, analytical columns, gases, detector, and
strip-chart recorder. A data system is recommended for measuring peak
areas.
5.6.1 Column 1--1.8 m long x 4 mm ID glass, packed with 10% Carbowax
20 M/2% KOH on Chromosorb W-AW (80/100 mesh) or equivalent. This column
was used to develop the method performance statements in Section 14.
Guidelines for the use of alternate column packings are provided in
Section 12.2.
5.6.2 Column 2--1.8 m long x 4 mm ID glass, packed with 10% SP-2250
on Supel-coport (100/120 mesh) or equivalent.
5.6.3 Detector--Nitrogen-phosphorus, reductive Hall, or Thermal
Energy Analyzer detector. \1 2\ These detectors have proven effective in
the analysis of wastewaters for the parameters listed in the scope
(Section 1.1). A nitrogen-phosphorus detector was used to develop the
method performance statements in Section 14. Guidelines for the use of
alternate detectors are provided in Section 12.2.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.2 Sodium hydroxide solution (10 N)--Dissolve 40 g of NaOH (ACS) in
reagent water and dilute to 100 ml.
[[Page 147]]
6.3 Sodium thiosulfate--(ACS) Granular.
6.4 Sulfuric acid (1 + 1)--Slowly, add 50 mL of
H2SO4 (ACS, sp. gr. 1.84) to 50 mL of reagent
water.
6.5 Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at
400 [deg]C for 4 h in a shallow tray.
6.6 Hydrochloric acid (1 + 9)--Add one volume of concentrated HCl
(ACS) to nine volumes of reagent water.
6.7 Acetone, methanol, methylene chloride, pentane--Pesticide
quality or equivalent.
6.8 Ethyl ether--Nanograde, redistilled in glass if necessary.
6.8.1 Ethyl ether must be shown to be free of peroxides before it is
used as indicated by EM Laboratories Quant test strips. (Available from
Scientific Products Co., Cat No. P1126-8, and other suppliers.)
6.8.2 Procedures recommended for removal of peroxides are provided
with the test strips. After cleanup, 20 mL of ethyl alcohol preservative
must be added to each liter of ether.
6.9 Florisil--PR grade (60/100 mesh). Purchase activated at 1250
[deg]F and store in the dark in glass containers with ground glass
stoppers or foil-lined screw caps. Before use, activate each batch at
least 16 h at 130 [deg]C in a foil-covered glass container and allow to
cool.
6.10 Alumina--Basic activity Super I, W200 series (ICN Life Sciences
Group, No. 404571, or equivalent). To prepare for use, place 100 g of
alumina into a 500-mL reagent bottle and add 2 mL of reagent water. Mix
the alumina preparation thoroughly by shaking or rolling for 10 min and
let it stand for at least 2 h. The preparation should be homogeneous
before use. Keep the bottle sealed tightly to ensure proper activity.
6.11 Stock standard solutions (1.00 [micro]g/[micro]L)--Stock
standard solutions can be prepared from pure standard materials or
purchased as certified solutions.
6.11.1 Prepare stock standard solutions by accurately weighing about
0.0100 g of pure material. Dissolve the material in methanol and dilute
to volume in a 10-mL volumetric flask. Larger volumes can be used at the
convenience of the analyst. When compound purity is assayed to be 96% or
greater, the weight can be used without correction to calculate the
concentration of the stock standard. Commercially prepared stock
standards can be used at any concentration if they are certified by the
manufacturer or by an independent source.
6.11.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles. Store at 4 [deg]C and protect from light. Stock
standard solutions should be checked frequently for signs of degradation
or evaporation, especially just prior to preparing calibration standards
from them.
6.11.3 Stock standard solutions must be replaced after six months,
or sooner if comparison with check standards indicates a problem.
6.12 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Establish gas chromatographic operating conditions equivalent to
those given in Table 1. The gas chromatographic system can be calibrated
using the external standard technique (Section 7.2) or the internal
standard technique (Section 7.3).
7.2 External standard calibration procedure:
7.2.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask and diluting to volume
with methanol. One of the external standards should be at a
concentration near, but above, the MDL (Table 1) and the other
concentrations should correspond to the expected range of concentrations
found in real samples or should define the working range of the
detector.
7.2.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against the mass injected. The results can be used to prepare
a calibration curve for each compound. Alternatively, if the ratio of
response to amount injected (calibration factor) is a constant over the
working range (<10% relative standard deviation, RSD), linearity through
the origin can be assumed and the average ratio or calibration factor
can be used in place of a calibration curve.
7.3 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the compounds of interest. The analyst must
further demonstrate that the measurement of the internal standard is not
affected by method or matrix interferences. Because of these
limitations, no internal standard can be suggested that is applicable to
all samples.
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask. To each calibration
standard, add a known constant amount of one or more internal standards,
and dilute to volume with methanol. One of the standards should be at a
concentration near, but above, the MDL and the other concentrations
should correspond to the expected range of concentrations found in real
samples or should define the working range of the detector.
[[Page 148]]
7.3.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against concentration for each compound and internal standard.
Calculate response factors (RF) for each compound using Equation 1.
RF = (As)(Cis (Ais)(Cs)
Equation 1
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Cis = Concentration of the internal standard ([micro]g/L).
Cs = Concentration of the parameter to be measured ([micro]g/
L).
If the RF value over the working range is a constant (<10% RSD), the
RF can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.4 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of one or more
calibration standards. If the response for any parameter varies from the
predicted response by more than 15%, a new
calibration curve must be prepared for that compound.
7.5 Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the reagents.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Sections 10.4, 11.1, and 12.2) to improve the separations or lower the
cost of measurements. Each time such a modification is made to the
method, the analyst is required to repeat the procedure in Section 8.2.
8.1.3 Before processing any samples, the analyst must analyze a
reagent water blank to demonstrate that interferences from the
analytical system and glassware are under control. Each time a set of
samples is extracted or reagents are changed, a reagent water blank must
be processed as a safeguard against laboratory contamination.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing each parameter of interest at a concentration of 20 [micro]g/
mL in methanol. The QC check sample concentrate must be obtained from
the U.S. Environmental Protection Agency, Environmental Monitoring and
Support Laboratory in Cincinnati, Ohio, if available. If not available
from that source, the QC check sample concentrate must be obtained from
another external source. If not available from either source above, the
QC check sample concentrate must be prepared by the laboratory using
stock standards prepared independently from those used for calibration.
8.2.2 Using a pipet, prepare QC check samples at a concentration of
20 [micro]g/L by adding 1.00 mL of QC check sample concentrate to each
of four 1-L aliquots of reagent water.
8.2.3 Analyze the well-mixed QC check samples according to the
method beginning in Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 2. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If
[[Page 149]]
any individual s exceeds the precision limit or any individual X falls
outside the range for accuracy, the system performance is unacceptable
for that parameter. Locate and correct the source of the problem and
repeat the test for all parameters of interest beginning with Section
8.2.2.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at 20 [micro]g/L or 1 to 5 times higher than the
background concentration determined in Section 8.3.2, whichever
concentration would be larger.
8.3.1.3 If it is impractical to determine background levels before
spiking (e.g., maximum holding times will be exceeded), the spike
concentration should be (1) the regulatory concentration limit, if any;
or, if none (2) the larger of either 5 times higher than the expected
background concentration or 20 [micro]g/L.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second sample aliquot with 1.0 mL
of the QC check sample concentrate and analyze it to determine the
concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100(A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 2. These acceptance
criteria were caluclated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\18\ If spiking was performed at a concentration lower than 20 [micro]g/
L, the analyst must use either the QC acceptance criteria in Table 2, or
optional QC acceptance criteria caluclated for the specific spike
concentration. To calculate optional acceptance criteria for the
recovery of a parameter: (1) Calculate accuracy (X') using the equation
in Table 3, substituting the spike concentration (T) for C; (2)
calculate overall precision (S') using the equation in Table 3,
substituting X' for X; (3) calculate the range for recovery at the spike
concentration as (100 X'/T) 2.44(100 S'/T)%. \18\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory.
8.4.1 Prepare the QC check standard by adding 1.0 mL of QC check
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The
QC check standard needs only to contain the parameters that failed
criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
2. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2sp to P + 2sp.
If P = 90% and sp = 10%, for example, the accuracy interval
is expressed as 70-110%. Update the accuracy assessment for each
parameter on a regular basis (e.g. after each five to ten new accuracy
measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of
[[Page 150]]
the samples. Field duplicates may be analyzed to assess the precision of
the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as gas chromatography with a dissimilar column, specific element
detector, or mass spectrometer must be used. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevant performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices \19\ should be followed, except that the bottle must
not be prerinsed with sample before collection. Composite samples should
be collected in refrigerated glass containers in accordance with the
requirements of the program. Automatic sampling equipment must be as
free as possible of Tygon tubing and other potential sources of
contamination.
9.2 All samples must be iced or refrigerated at 4 [deg]C from the
time of collection until extraction. Fill the sample bottles and, if
residual chlorine is present, add 80 mg of sodium thiosulfate per liter
of sample and mix well. EPA Methods 330.4 and 330.5 may be used for
measurement of residual chlorine. \20\ Field test kits are available for
this purpose. If N-nitrosodiphenylamine is to be determined, adjust the
sample pH to 7 to 10 with sodium hydroxide solution or sulfuric acid.
9.3 All samples must be extracted within 7 days of collection and
completely analyzed within 40 days of extraction. \4\
9.4 Nitrosamines are known to be light sensitive. \7\ Samples should
be stored in amber or foil-wrapped bottles in order to minimize
photolytic decomposition.
10. Sample Extraction
10.1 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Pour the entire sample into a 2-L
separatory funnel. Check the pH of the sample with wide-range pH paper
and adjust to within the range of 5 to 9 with sodium hydroxide solution
or sulfuric acid.
10.2 Add 60 mL of methylene chloride to the sample bottle, seal, and
shake 30 s to rinse the inner surface. Transfer the solvent to the
separatory funnel and extract the sample by shaking the funnel for 2 min
with periodic venting to release excess pressure. Allow the organic
layer to separate from the water phase for a minimum of 10 min. If the
emulsion interface between layers is more than one-third the volume of
the solvent layer, the analyst must employ mechanical techniques to
complete the phase separation. The optimum technique depends upon the
sample, but may include stirring, filtration of the emulsion through
glass wool, centrifugation, or other physical methods. Collect the
methylene chloride extract in a 250-mL Erlenmeyer flask.
10.3 Add a second 60-mL volume of methylene chloride to the sample
bottle and repeat the extraction procedure a second time, combining the
extracts in the Erlenmeyer flask. Perform a third extraction in the same
manner.
10.4 Assemble a Kuderna-Danish (K-D) concentrator by attaching a 10-
mL concentrator tube to a 500-mL evaporative flask. Other concentration
devices or techniques may be used in place of the K-D concentrator if
the requirements of Section 8.2 are met.
10.5 Add 10 mL of hydrochloric acid to the combined extracts and
shake for 2 min. Allow the layers to separate. Pour the combined extract
through a solvent-rinsed drying column containing about 10 cm of
anhydrous sodium sulfate, and collect the extract in the K-D
concentrator. Rinse the Erlenmeyer flask and column with 20 to 30 mL of
methylene chloride to complete the quantitative transfer.
10.6 Add one or two clean boiling chips to the evaporative flask and
attach a three-ball Snyder column. Prewet the Snyder column by adding
about 1 mL of methylene chloride to the top. Place the K-D apparatus on
a hot water bath (60 to 65 [deg]C) so that the concentrator tube is
partially immersed in the hot water, and the entire lower rounded
surface of the flask is bathed with hot vapor. Adjust the vertical
position of the apparatus and the water temperature as required to
complete the concentration in 15 to 20 min. At the proper rate of
distillation the balls of the column will actively chatter but the
chambers will not flood with condensed solvent. When the apparent volume
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain
and cool for at least 10 min.
10.7 Remove the Snyder column and rinse the flask and its lower
joint into the concentrator tube with 1 to 2 mL of methylene chloride. A
5-mL syringe is recommended for this operation. Stopper the concentrator
tube and store refrigerated if further processing will not be performed
immediately. If the extract will be stored longer than two days, it
should be transferred to a Teflon-sealed screw-cap vial. If N-
nitrosodiphenylamine is to be measured by gas chromatography, the
analyst must first use a cleanup column to eliminate diphenylamine
interference (Section 11). If N-nitrosodiphenylamine is of no interest,
the analyst may proceed directly with gas chromatographic analysis
(Section 12).
10.8 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to a 1000-
mL graduated cylinder. Record the sample volume to the nearest 5 mL.
[[Page 151]]
11. Cleanup and Separation
11.1 Cleanup procedures may not be necessary for a relatively clean
sample matrix. If particular circumstances demand the use of a cleanup
procedure, the analyst may use either procedure below or any other
appropriate procedure. However, the analyst first must demonstrate that
the requirements of Section 8.2 can be met using the method as revised
to incorporate the cleanup procedure. Diphenylamine, if present in the
original sample extract, must be separated from the nitrosamines if N-
nitrosodiphenylamine is to be determined by this method.
11.2 If the entire extract is to be cleaned up by one of the
following procedures, it must be concentrated to 2.0 mL. To the
concentrator tube in Section 10.7, add a clean boiling chip and attach a
two-ball micro-Snyder column. Prewet the column by adding about 0.5 mL
of methylene chloride to the top. Place the micr-K-D apparatus on a hot
water bath (60 to 65 [deg]C) so that the concentrator tube is partially
immersed in the hot water. Adjust the vertical position of the apparatus
and the water temperature as required to complete the concentration in 5
to 10 min. At the proper rate of distillation the balls of the column
will actively chatter but the chambers will not flood. When the apparent
volume of liquid reaches about 0.5 mL, remove the K-D apparatus and
allow it to drain and cool for at least 10 min. Remove the micro-Snyder
column and rinse its lower joint into the concentrator tube with 0.2 mL
of methylene chloride. Adjust the final volume to 2.0 mL and proceed
with one of the following cleanup procedures.
11.3 Florisil column cleanup for nitrosamines:
11.3.1 Place 22 g of activated Florisil into a 22-mm ID
chromatographic column. Tap the column to settle the Florisil and add
about 5 mm of anhydrous sodium sulfate to the top.
11.3.2 Preelute the column with 40 mL of ethyl ether/pentane (15 +
85)(V/V). Discard the eluate and just prior to exposure of the sodium
sulfate layer to the air, quantitatively transfer the 2-mL sample
extract onto the column using an additional 2 mL of pentane to complete
the transfer.
11.3.3 Elute the column with 90 mL of ethyl ether/pentane (15 +
85)(V/V) and discard the eluate. This fraction will contain the
diphenylamine, if it is present in the extract.
11.3.4 Next, elute the column with 100 mL of acetone/ethyl ether (5
+ 95)(V/V) into a 500-mL K-D flask equipped with a 10-mL concentrator
tube. This fraction will contain all of the nitrosamines listed in the
scope of the method.
11.3.5 Add 15 mL of methanol to the collected fraction and
concentrate as in Section 10.6, except use pentane to prewet the column
and set the water bath at 70 to 75 [deg]C. When the apparatus is cool,
remove the Snyder column and rinse the flask and its lower joint into
the concentrator tube with 1 to 2 mL of pentane. Analyze by gas
chromatography (Section 12).
11.4 Alumina column cleanup for nitrosamines:
11.4.1 Place 12 g of the alumina preparation (Section 6.10) into a
10-mm ID chromatographic column. Tap the column to settle the alumina
and add 1 to 2 cm of anhydrous sodium sulfate to the top.
11.4.2 Preelute the column with 10 mL of ethyl ether/pentane (3 +
7)(V/V). Discard the eluate (about 2 mL) and just prior to exposure of
the sodium sulfate layer to the air, quantitatively transfer the 2 mL
sample extract onto the column using an additional 2 mL of pentane to
complete the transfer.
11.4.3 Just prior to exposure of the sodium sulfate layer to the
air, add 70 mL of ethyl ether/pentane (3 + 7)(V/V). Discard the first 10
mL of eluate. Collect the remainder of the eluate in a 500-mL K-D flask
equipped with a 10 mL concentrator tube. This fraction contains N-
nitrosodiphenylamine and probably a small amount of N-nitrosodi-n-
propylamine.
11.4.4 Next, elute the column with 60 mL of ethyl ether/pentane (1 +
1)(V/V), collecting the eluate in a second K-D flask equipped with a 10-
mL concentrator tube. Add 15 mL of methanol to the K-D flask. This
fraction will contain N-nitrosodimethylamine, most of the N-nitrosodi-n-
propylamine and any diphenylamine that is present.
11.4.5 Concentrate both fractions as in Section 10.6, except use
pentane to prewet the column. When the apparatus is cool, remove the
Snyder column and rinse the flask and its lower joint into the
concentrator tube with 1 to 2 mL of pentane. Analyze the fractions by
gas chromatography (Section 12).
12. Gas Chromatography
12.1 N-nitrosodiphenylamine completely reacts to form diphenylamine
at the normal operating temperatures of a GC injection port (200 to 250
[deg]C). Thus, N-nitrosodiphenylamine is chromatographed and detected as
diphenylamine. Accurate determination depends on removal of
diphenylamine that may be present in the original extract prior to GC
analysis (See Section 11).
12.2 Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are retention times and MDL
that can be achieved under these conditions. Examples of the separations
achieved by Column 1 are shown in Figures 1 and 2. Other packed or
capillary (open-tubular) columns, chromatographic conditions, or
detectors may be used if the requirements of Section 8.2 are met.
12.3 Calibrate the system daily as described in Section 7.
[[Page 152]]
12.4 If the extract has not been subjected to one of the cleanup
procedures in Section 11, it is necessary to exchange the solvent from
methylene chloride to methanol before the thermionic detector can be
used. To a 1 to 10-mL volume of methylene chloride extract in a
concentrator tube, add 2 mL of methanol and a clean boiling chip. Attach
a two-ball micro-Snyder column to the concentrator tube. Prewet the
column by adding about 0.5 mL of methylene chloride to the top. Place
the micro-K-D apparatus on a boiling (100 [deg]C) water bath so that the
concentrator tube is partially immersed in the hot water. Adjust the
vertical position of the apparatus and the water temperature as required
to complete the concentration in 5 to 10 min. At the proper rate of
distillation the balls of the column will actively chatter but the
chambers will not flood. When the apparent volume of liquid reaches
about 0.5 mL, remove the K-D apparatus and allow it to drain and cool
for at least 10 min. Remove the micro-Snyder column and rinse its lower
joint into the concentrator tube with 0.2 mL of methanol. Adjust the
final volume to 2.0 mL.
12.5 If the internal standard calibration procedure is being used,
the internal standard must be added to the sample extract and mixed
thoroughly immediately before injection into the gas chromatograph.
12.6 Inject 2 to 5 [micro]L of the sample extract or standard into
the gas chromatograph using the solvent-flush technique. \21\ Smaller
(1.0 [micro]L) volumes may be injected if automatic devices are
employed. Record the volume injected to the nearest 0.05 [micro]L, and
the resulting peak size in area or peak height units.
12.7 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
12.8 If the response for a peak exceeds the working range of the
system, dilute the extract and reanalyze.
12.9 If the measurement of the peak response is prevented by the
presence of interferences, further cleanup is required.
13. Calculations
13.1 Determine the concentration of individual compounds in the
sample.
13.1.1 If the external standard calibration procedure is used,
calculate the amount of material injected from the peak response using
the calibration curve or calibration factor determined in Section 7.2.2.
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.105
Equation 2
where:
A = Amount of material injected (ng).
Vi = Volume of extract injected ([micro]L).
Vt = Volume of total extract ([micro]L).
Vs = Volume of water extracted (mL).
13.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.106
Equation 3
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Is = Amount of internal standard added to each extract
([micro]g).
Vo = Volume of water extracted (L).
13.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
14. Method Performance
14.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \3\ The MDL concentrations
listed in Table 1 were obtained using reagent water. \22\ Similar
results were achieved using representative wastewaters. The MDL actually
achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
14.2 This method has been tested for linearity of spike recovery
from reagent water and has been demonstrated to be applicable over the
concentration range from 4 x MDL to 1000 x MDL. \22\
14.3 This method was tested by 17 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
at six concentrations over the range 0.8 to 55 [micro]g/L. \23\ Single
operator precision, overall precision, and method accuracy were found to
be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 3.
[[Page 153]]
References
1. Fine, D.H., Lieb, D., and Rufeh, R. ``Principle of Operation of
the Thermal Energy Analyzer for the Trace Analysis of Volatile and Non-
volatile N-nitroso Compounds,'' Journal of Chromatography, 107, 351
(1975).
2. Fine, D.H., Hoffman, F., Rounbehler, D.P., and Belcher, N.M.
``Analysis of N-nitroso Compounds by Combined High Performance Liquid
Chromatography and Thermal Energy Analysis,'' Walker, E.A., Bogovski, P.
and Griciute, L., Editors, N-nitroso Compounds--Analysis and Formation,
Lyon, International Agency for Research on Cancer (IARC Scientific
Publications No. 14), pp. 43-50 (1976).
3. 40 CFR part 136, appendix B.
4. ``Determination of Nitrosamines in Industrial and Municipal
Wastewaters,'' EPA 600/4-82-016, National Technical Information Service,
PB82-199621, Springfield, Virginia 22161, April 1982.
5. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard
Practices for Preparation of Sample Containers and for Preservation of
Organic Constituents,'' American Society for Testing and Materials,
Philadelphia.
6. Buglass, A.J., Challis, B.C., and Osborn, M.R. ``Transnitrosation
and Decomposition of Nitrosamines,'' Bogovski, P. and Walker, E.A.,
Editors, N-nitroso Compounds in the Environment, Lyon, International
Agency for Research on Cancer (IARC Scientific Publication No. 9), pp.
94-100 (1974).
7. Burgess, E.M., and Lavanish, J.M. ``Photochemical Decomposition
of N-nitrosamines,'' Tetrahedon Letters, 1221 (1964)
8. Druckrey, H., Preussmann, R., Ivankovic, S., and Schmahl, D.
``Organotrope Carcinogene Wirkungen bei 65 Verschiedenen N-
NitrosoVerbindungen an BD-Ratten,'' Z. Krebsforsch., 69, 103 (1967).
9. Fiddler, W. ``The Occurrence and Determination of N-nitroso
Compounds,'' Toxicol. Appl. Pharmacol., 31, 352 (1975).
10. ``Carcinogens--Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
11. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
Part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
12. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
13. Lijinsky, W. ``How Nitrosamines Cause Cancer,'' New Scientist,
73, 216 (1977).
14. Mirvish, S.S. ``N-Nitroso compounds: Their Chemical and in vivo
Formation and Possible Importance as Environmental Carcinogens,'' J.
Toxicol. Environ. Health, 3, 1267 (1977).
15. ``Reconnaissance of Environmental Levels of Nitrosamines in the
Central United States,'' EPA-330/1-77-001, National Enforcement
Investigations Center, U.S. Environmental Protection Agency (1977).
16. ``Atmospheric Nitrosamine Assessment Report,'' Office of Air
Quality Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, North Carolina (1976).
17. ``Scientific and Technical Assessment Report on Nitrosamines,''
EPA-660/6-7-001, Office of Research and Development, U.S. Environmental
Protection Agency (1976).
18. Provost, L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value of 1.22
derived in this report.)
19. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard
Practices for Sampling Water,'' American Society for Testing and
Materials, Philadelphia.
20. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268, March 1979.
21. Burke, J. A. ``Gas Chromatography for Pesticide Residue
Analysis; Some Practical Aspects,'' Journal of the Association of
Official Analytical Chemists, 48, 1037 (1965).
22. ``Method Detection Limit and Analytical Curve Studies EPA
Methods 606, 607, and 608,'' Special letter report for EPA Contract 68-
03-2606, U.S. Environmental Protection Agency, Environmental Monitoring
and Support Laboratory, Cincinnati, Ohio 45268, June 1980.
23. ``EPA Method Study 17 Method 607--Nitrosamines,'' EPA 600/4-84-
051, National Technical Information Service, PB84-207646, Springfield,
Virginia 22161, June 1984.
Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
Retention time (min) Method
-------------------------- detection
Parameter limit
Column 1 Column 2 ([micro]g/
L)
------------------------------------------------------------------------
N-Nitrosodimethylamine........... 4.1 0.88 0.15
N-Nitrosodi-n-propylamine........ 12.1 4.2 .46
[[Page 154]]
N-Nitrosodiphenylamine \a\....... \b\ 12.8 \c\ 6.4 .81
------------------------------------------------------------------------
Column 1 conditions: Chromosorb W-AW (80/100 mesh) coated with 10%
Carbowax 20 M/2% KOH packed in a 1.8 m long x 4mm ID glass column with
helium carrier gas at 40 mL/min flow rate. Column temperature held
isothermal at 110 [deg]C, except where otherwise indicated.
Column 2 conditions: Supelcoport (100/120 mesh) coated with 10% SP-2250
packed in a 1.8 m long x 4 mm ID glass column with helium carrier gas
at 40 mL/min flow rate. Column temperature held isothermal at 120
[deg]C, except where otherwise indicated.
\a\ Measured as diphenylamine.
\b\ 220 [deg]C column temperature.
\c\ 210 [deg]C column temperature.
Table 2--QC Acceptance Criteria--Method 607
----------------------------------------------------------------------------------------------------------------
Test conc. Limit for s Range for X Range for
Parameter ([micro]g/ ([micro]g/ ([micro]g/ P, Ps
L) L) L) (percent)
----------------------------------------------------------------------------------------------------------------
N-Nitrosodimethylamine...................................... 20 3.4 4.6-20.0 13-109
N-Nitrosodiphenyl........................................... 20 6.1 2.1-24.5 D-139
N-Nitrosodi-n-propylamine................................... 20 5.7 11.5-26.8 45-146
----------------------------------------------------------------------------------------------------------------
s = Standard deviation for four recovery measurements, in [micro]g/L (Section 8.2.4).
X = Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps = Percent recovery measured (Section 8.3.2, Section 8.4.2).
D = Detected; result must be greater than zero.
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 3.
Table 3--Method Accuracy and Precision as Functions of Concentration--Method 607
----------------------------------------------------------------------------------------------------------------
Accuracy, as Single analyst Overall
Parameter recovery, X' precision, sr' precision, S'
([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
N-Nitrosodimethylamine.......................................... 0.37C + 0.06 0.25X-0.04 0.25X + 0.11
N-Nitrosodiphenylamine.......................................... 0.64C + 0.52 0.36X-1.53 0.46X-0.47
N-Nitrosodi-n-propylamine....................................... 0.96C-0.07 0.15X + 0.13 0.21X + 0.15
----------------------------------------------------------------------------------------------------------------
X' = Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/L.
sr' = Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S' = Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C = True value for the concentration, in [micro]g/L.
X = Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
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[GRAPHIC] [TIFF OMITTED] TC02JY92.017
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[GRAPHIC] [TIFF OMITTED] TC02JY92.018
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Method 608.3--Organochlorine Pesticides And PCBs By GC/HSD
1. Scope and Application
1.1 This method is for determination of organochlorine pesticides
and polychlorinated biphenyls (PCBs) in industrial discharges and other
environmental samples by gas chromatography (GC) combined with a
halogen-specific detector (HSD; e.g., electron capture, electrolytic
conductivity), as provided under 40 CFR 136.1. This revision is based on
a previous protocol (Reference 1), on the revision promulgated October
26, 1984, on an inter-laboratory method validation study (Reference 2),
and on EPA Method 1656 (Reference 16). The analytes that may be
qualitatively and quantitatively determined using this method and their
CAS Registry numbers are listed in Table 1.
1.2 This method may be extended to determine the analytes listed in
Table 2. However, extraction or gas chromatography challenges for some
of these analytes may make quantitative determination difficult.
1.3 When this method is used to analyze unfamiliar samples for an
analyte listed in Table 1 or Table 2, analyte identification must be
supported by at least one additional qualitative technique. This method
gives analytical conditions for a second GC column that can be used to
confirm and quantify measurements. Additionally, Method 625.1 provides
gas chromatograph/mass spectrometer (GC/MS) conditions appropriate for
the qualitative confirmation of results for the analytes listed in
Tables 1 and 2 using the extract produced by this method, and Method
1699 (Reference 18) provides high resolution GC/MS conditions for
qualitative confirmation of results using the original sample. When such
methods are used to confirm the identifications of the target analytes,
the quantitative results should be derived from the procedure with the
calibration range and sensitivity that are most appropriate for the
intended application.
1.4 The large number of analytes in Tables 1 and 2 makes testing
difficult if all analytes are determined simultaneously. Therefore, it
is necessary to determine and perform quality control (QC) tests for the
``analytes of interest'' only. The analytes of interest are those
required to be determined by a regulatory/control authority or in a
permit, or by a client. If a list of analytes is not specified, the
analytes in Table 1 must be determined, at a minimum, and QC testing
must be performed for these analytes. The analytes in Table 1 and some
of the analytes in Table 2 have been identified as Toxic Pollutants (40
CFR 401.15), expanded to a list of Priority Pollutants (40 CFR part 423,
appendix A).
1.5 In this revision to Method 608, Chlordane has been listed as the
alpha- and gamma- isomers in Table 1. Reporting may be by the individual
isomers, or as the sum of the concentrations of these isomers, as
requested or required by a regulatory/control authority or in a permit.
Technical Chlordane is listed in Table 2 and may be used in cases where
historical reporting has only been the Technical Chlordane. Toxaphene
and the PCBs have been moved from Table 1 to Table 2 (Additional
Analytes) to distinguish these analytes from the analytes required in
quality control tests (Table 1). QC acceptance criteria for Toxaphene
and the PCBs have been retained in Table 4 and may continue to be
applied if desired, or if these analytes are requested or required by a
regulatory/control authority or in a permit. Method 1668C (Reference 17)
may be useful for determination of PCBs as individual chlorinated
biphenyl congeners, and Method 1699 (Reference 18) may be useful for
determination of the pesticides listed in this method. However, at the
time of writing of this revision, Methods 1668C and 1699 had not been
approved for use at 40 CFR part 136.
1.6 Method detection limits (MDLs; Reference 3) for the analytes in
Tables 1 and some of the analytes in Table 2 are listed in those tables.
These MDLs were determined in reagent water (Reference 3). Advances in
analytical technology, particularly the use of capillary (open-tubular)
columns, allowed laboratories to routinely achieve MDLs for the analytes
in this method that are 2-10 times lower than those in the version
promulgated in 1984. The MDL for an analyte in a specific wastewater may
differ from those listed, depending upon the nature of interferences in
the sample matrix.
1.6.1 EPA has promulgated this method at 40 CFR part 136 for use in
wastewater compliance monitoring under the National Pollutant Discharge
Elimination System (NPDES). The data reporting practices described in
section 15.6 are focused on such monitoring needs and may not be
relevant to other uses of the method.
1.6.2 This method includes ``reporting limits'' based on EPA's
``minimum level'' (ML) concept (see the glossary in section 23). Tables
1 and 2 contain MDL values and ML values for many of the analytes.
1.7 The separatory funnel and continuous liquid-liquid sample
extraction and concentration steps in this method are essentially the
same as those steps in Methods 606, 609, 611, and 612. Thus, a single
sample may be extracted to measure the analytes included in the scope of
each of these methods. Samples may also be extracted using a disk-based
solid-phase extraction (SPE) procedure developed by the 3M Corporation
and approved by EPA as an Alternate Test Procedure (ATP) for wastewater
analyses in 1995 (Reference 20).
1.8 This method is performance-based. It may be modified to improve
performance (e.g., to overcome interferences or improve
[[Page 158]]
the accuracy of results) provided all performance requirements are met.
1.8.1 Examples of allowed method modifications are described at 40
CFR 136.6. Other examples of allowed modifications specific to this
method are described in section 8.1.2.
1.8.2 Any modification beyond those expressly permitted at 40 CFR
136.6 or in section 8.1.2 of this method shall be considered a major
modification subject to application and approval of an alternate test
procedure under 40 CFR 136.4 and 136.5.
1.8.3 For regulatory compliance, any modification must be
demonstrated to produce results equivalent or superior to results
produced by this method when applied to relevant wastewaters (section
8.1.2).
1.9 This method is restricted to use by or under the supervision of
analysts experienced in the use of GC/HSD. The laboratory must
demonstrate the ability to generate acceptable results with this method
using the procedure in section 8.2.
1.10 Terms and units of measure used in this method are given in the
glossary at the end of the method.
2. Summary of Method
2.1 A measured volume of sample, the amount required to meet an MDL
or reporting limit (nominally 1-L), is extracted with methylene chloride
using a separatory funnel, a continuous liquid/liquid extractor, or
disk-based solid-phase extraction equipment. The extract is dried and
concentrated for cleanup, if required. After cleanup, or if cleanup is
not required, the extract is exchanged into an appropriate solvent and
concentrated to the volume necessary to meet the required compliance or
detection limit, and analyzed by GC/HSD.
2.2 Qualitative identification of an analyte in the extract is
performed using the retention times on dissimilar GC columns.
Quantitative analysis is performed using the peak areas or peak heights
for the analyte on the dissimilar columns with either the external or
internal standard technique.
2.3 Florisil[supreg], alumina, a C18 solid-phase cleanup, and an
elemental sulfur cleanup procedure are provided to aid in elimination of
interferences that may be encountered. Other cleanup procedures may be
used if demonstrated to be effective for the analytes in a wastewater
matrix.
3. Contamination and Interferences
3.1 Solvents, reagents, glassware, and other sample processing lab
ware may yield artifacts, elevated baselines, or matrix interferences
causing misinterpretation of chromatograms. All materials used in the
analysis must be demonstrated free from contamination and interferences
by running blanks initially and with each extraction batch (samples
started through the extraction process in a given 24-hour period, to a
maximum of 20 samples--see Glossary for detailed definition), as
described in section 8.5. Specific selection of reagents and
purification of solvents by distillation in all-glass systems may be
required. Where possible, labware is cleaned by extraction or solvent
rinse, or baking in a kiln or oven.
3.2 Glassware must be scrupulously cleaned (Reference 4). Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed by detergent washing with
hot water, and rinses with tap water and reagent water. The glassware
should then be drained dry, and heated at 400 [deg]C for 15-30 minutes.
Some thermally stable materials, such as PCBs, may require higher
temperatures and longer baking times for removal. Solvent rinses with
pesticide quality acetone, hexane, or other solvents may be substituted
for heating. Do not heat volumetric labware above 90 [deg]C. After
drying and cooling, store inverted or capped with solvent-rinsed or
baked aluminum foil in a clean environment to prevent accumulation of
dust or other contaminants.
3.3 Interferences by phthalate esters can pose a major problem in
pesticide analysis when using the electron capture detector. The
phthalate esters generally appear in the chromatogram as large late
eluting peaks, especially in the 15 and 50% fractions from
Florisil[supreg]. Common flexible plastics contain varying amounts of
phthalates that may be extracted or leached from such materials during
laboratory operations. Cross contamination of clean glassware routinely
occurs when plastics are handled during extraction steps, especially
when solvent-wetted surfaces are handled. Interferences from phthalates
can best be minimized by avoiding use of non-fluoropolymer plastics in
the laboratory. Exhaustive cleanup of reagents and glassware may be
required to eliminate background phthalate contamination (References 5
and 6). Interferences from phthalate esters can be avoided by using a
microcoulometric or electrolytic conductivity detector.
3.4 Matrix interferences may be caused by contaminants co-extracted
from the sample. The extent of matrix interferences will vary
considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled.
Interferences extracted from samples high in total organic carbon (TOC)
may result in elevated baselines, or by enhancing or suppressing a
signal at or near the retention time of an analyte of interest. Analyses
of the matrix spike and matrix spike duplicate (Section 8.3) may be
useful in identifying matrix interferences, and the cleanup procedures
in Section 11 may aid in eliminating these interferences. EPA has
provided guidance that may aid in overcoming matrix
[[Page 159]]
interferences (Reference 7); however, unique samples may require
additional cleanup approaches to achieve the MDLs listed in Tables 1 and
2.
4. Safety
4.1 Hazards associated with each reagent used in this method have
not been precisely defined; however, each chemical compound should be
treated as a potential health hazard. From this viewpoint, exposure to
these chemicals must be reduced to the lowest possible level by whatever
means available. The laboratory is responsible for maintaining a current
awareness file of OSHA regulations regarding the safe handling of the
chemicals specified in this method. A reference file of safety data
sheets (SDSs, OSHA, 29 CFR 1910.12009(g)) should also be made available
to all personnel involved in sample handling and chemical analysis.
Additional references to laboratory safety are available and have been
identified (References 8 and 9) for the information of the analyst.
4.2 The following analytes covered by this method have been
tentatively classified as known or suspected human or mammalian
carcinogens: 4,4[min]-DDT, 4,4[min]-DDD, the BHCs, and the PCBs. Primary
standards of these toxic analytes should be prepared in a chemical fume
hood, and a NIOSH/MESA approved toxic gas respirator should be worn when
high concentrations are handled.
4.3 This method allows the use of hydrogen as a carrier gas in place
of helium (section 5.8.2). The laboratory should take the necessary
precautions in dealing with hydrogen, and should limit hydrogen flow at
the source to prevent buildup of an explosive mixture of hydrogen in
air.
5. Apparatus and Materials
Note: Brand names and suppliers are for illustration purposes only.
No endorsement is implied. Equivalent performance may be achieved using
equipment and materials other than those specified here. Demonstrating
that the equipment and supplies used in the laboratory achieve the
required performance is the responsibility of the laboratory. Suppliers
for equipment and materials in this method may be found through an on-
line search. Please do not contact EPA for supplier information.
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--Amber glass bottle large enough to contain
the necessary sample volume (nominally 1 L), fitted with a
fluoropolymer-lined screw cap. Foil may be substituted for fluoropolymer
if the sample is not corrosive. If amber bottles are not available,
protect samples from light. Unless pre-cleaned, the bottle and cap liner
must be washed, rinsed with acetone or methylene chloride, and dried
before use to minimize contamination.
5.1.2 Automatic sampler (optional)--The sampler must use a glass or
fluoropolymer container and tubing for sample collection. If the sampler
uses a peristaltic pump, a minimum length of compressible silicone
rubber tubing may be used. Before use, rinse the compressible tubing
thoroughly with methanol, followed by repeated rinsing with reagent
water to minimize the potential for sample contamination. An integrating
flow meter is required to collect flow proportional composites. The
sample container must be kept refrigerated at <=6 [deg]C and protected
from light during compositing.
5.2. Lab ware.
5.2.1 Extraction.
5.2.1.1 pH measurement.
5.2.1.1.1 pH meter, with combination glass electrode.
5.2.1.1.2 pH paper, wide range (Hydrion Papers, or equivalent).
5.2.1.2 Separatory funnel--Size appropriate to hold the sample and
extraction solvent volumes, equipped with fluoropolymer stopcock.
5.2.1.3 Continuous liquid-liquid extractor--Equipped with
fluoropolymer or glass connecting joints and stopcocks requiring no
lubrication. (Hershberg-Wolf Extractor, Ace Glass Company, Vineland, NJ,
or equivalent.)
5.2.1.3.1 Round-bottom flask, 500-mL, with heating mantle.
5.2.1.3.2 Condenser, Graham, to fit extractor.
5.2.1.4 Solid-phase extractor--90-mm filter apparatus (Figure 2) or
multi-position manifold.
Note: The approved ATP for solid-phase extraction is limited to
disk-based extraction media and associated peripheral equipment.
5.2.1.4.1 Vacuum system--Capable of achieving 0.1 bar (25 inch) Hg
(house vacuum, vacuum pump, or water aspirator), equipped with shutoff
valve and vacuum gauge.
5.2.1.4.2 Vacuum trap--Made from 500-mL sidearm flask fitted with
single-hole rubber stopper and glass tubing.
5.2.2 Filtration.
5.2.2.1 Glass powder funnel, 125- to 250-mL.
5.2.2.2 Filter paper for above, Whatman 41, or equivalent.
5.2.2.3 Prefiltering aids--90-mm 1-[micro]m glass fiber filter or
Empore[supreg] Filter Aid 400.
5.2.3 Drying column.
5.2.3.1 Chromatographic column--Approximately 400 mm long x 15 mm
ID, with fluoropolymer stopcock and coarse frit filter disc (Kontes or
equivalent).
5.2.3.2 Glass wool--Pyrex, extracted with methylene chloride or
baked at 450 [deg]C for 1 hour minimum.
[[Page 160]]
5.2.4 Column for Florisil[supreg] or alumina cleanup--Approximately
300 mm long x 10 mm ID, with fluoropolymer stopcock. (This column is not
required if cartridges containing Florisil[supreg] are used.)
5.2.5 Concentration/evaporation.
Note: Use of a solvent recovery system with the K-D or other solvent
evaporation apparatus is strongly recommended.
5.2.5.1 Kuderna-Danish concentrator.
5.2.5.1.1 Concentrator tube, Kuderna-Danish--10-mL, graduated
(Kontes or equivalent). Calibration must be checked at the volumes
employed for extract volume measurement. A ground-glass stopper is used
to prevent evaporation of extracts.
5.2.5.1.2 Evaporative flask, Kuderna-Danish--500-mL (Kontes or
equivalent). Attach to concentrator tube with connectors.
5.2.5.1.3 Snyder column, Kuderna/Danish--Three-ball macro (Kontes or
equivalent).
5.2.5.1.4 Snyder column--Two-ball micro (Kontes or equivalent).
5.2.5.1.5 Water bath--Heated, with concentric ring cover, capable of
temperature control (2 [deg]C), installed in a
hood using appropriate engineering controls to limit exposure to solvent
vapors.
5.2.5.2 Nitrogen evaporation device--Equipped with heated bath that
can be maintained at an appropriate temperature for the solvent and
analytes. (N-Evap, Organomation Associates, Inc., or equivalent).
5.2.5.3 Rotary evaporator--Buchi/Brinkman-American Scientific or
equivalent, equipped with a variable temperature water bath, vacuum
source with shutoff valve at the evaporator, and vacuum gauge.
5.2.5.3.1 A recirculating water pump and chiller are recommended, as
use of tap water for cooling the evaporator wastes large volumes of
water and can lead to inconsistent performance as water temperatures and
pressures vary.
5.2.5.3.2 Round-bottom flask--100-mL and 500-mL or larger, with
ground-glass fitting compatible with the rotary evaporator
Note: This equipment is used to prepare copper foil or copper powder
for removing sulfur from sample extracts (see Section 6.7.4).
5.2.5.4 Automated concentrator--Equipped with glassware sufficient
to concentrate 3-400 mL extract to a final volume of 1-10 mL under
controlled conditions of temperature and nitrogen flow (Turbovap, or
equivalent). Follow manufacturer's directions and requirements.
5.2.5.5 Boiling chips--Glass, silicon carbide, or equivalent,
approximately 10/40 mesh. Heat at 400 [deg]C for 30 minutes, or solvent
rinse or Soxhlet extract with methylene chloride.
5.2.6 Solid-phase extraction disks--90-mm extraction disks
containing 2 g of 8-[micro]m octadecyl (C18) bonded silica uniformly
enmeshed in a matrix of inert PTFE fibrils (3M Empore[supreg] or
equivalent). The disks should not contain any organic compounds, either
from the PTFE or the bonded silica, which will leach into the methylene
chloride eluant. One liter of reagent water should pass through the
disks in 2-5 minutes, using a vacuum of at least 25 inches of mercury.
Note: Extraction disks from other manufacturers may be used in this
procedure, provided that they use the same solid-phase materials (i.e.,
octadecyl bonded silica). Disks of other diameters also may be used, but
may adversely affect the flow rate of the sample through the disk.
5.3 Vials.
5.3.1 Extract storage--10- to 15-mL, amber glass, with
fluoropolymer-lined screw cap.
5.3.2 GC autosampler--1- to 5-mL, amber glass, with fluoropolymer-
lined screw- or crimp-cap, to fit GC autosampler.
5.4 Balances.
5.4.1 Analytical--Capable of accurately weighing 0.1 mg.
5.4.2 Top loading--Capable of weighing 10 mg.
5.5 Sample cleanup.
5.5.1 Oven--For baking and storage of adsorbents, capable of
maintaining a constant temperature (5 [deg]C) in
the range of 105-250 [deg]C.
5.5.2 Muffle furnace--Capable of cleaning glassware or baking sodium
sulfate in the range of 400-450 [deg]C.
5.5.3 Vacuum system and cartridges for solid-phase cleanup (see
Section 11.2).
5.5.3.1 Vacuum system--Capable of achieving 0.1 bar (25 in.) Hg
(house vacuum, vacuum pump, or water aspirator), equipped with shutoff
valve and vacuum gauge.
5.5.3.2 VacElute Manifold (Analytichem International, or
equivalent).
5.5.3.3 Vacuum trap--Made from 500-mL sidearm flask fitted with
single-hole rubber stopper and glass tubing.
5.5.3.4 Rack for holding 50-mL volumetric flasks in the manifold.
5.5.3.5 Cartridge--Mega Bond Elute, Non-polar, C18 Octadecyl, 10 g/
60 mL (Analytichem International or equivalent), used for solid-phase
cleanup of sample extracts (see Section 11.2).
5.5.4 Sulfur removal tube--40- to 50-mL bottle, test tube, or
Erlenmeyer flask with fluoropolymer-lined screw cap.
5.6 Centrifuge apparatus.
5.6.1 Centrifuge--Capable of rotating 500-mL centrifuge bottles or
15-mL centrifuge tubes at 5,000 rpm minimum.
5.6.2 Centrifuge bottle--500-mL, with screw cap, to fit centrifuge.
5.6.3 Centrifuge tube--15-mL, with screw cap, to fit centrifuge.
5.7 Miscellaneous lab ware--Graduated cylinders, pipettes, beakers,
volumetric flasks, vials, syringes, and other lab ware
[[Page 161]]
necessary to support the operations in this method.
5.8 Gas chromatograph--Dual-column with simultaneous split/
splitless, temperature programmable split/splitless (PTV), or on-column
injection; temperature program with isothermal holds, and all required
accessories including syringes, analytical columns, gases, and
detectors. An autosampler is highly recommended because it injects
volumes more reproducibly than manual injection techniques.
Alternatively, two separate single-column gas chromatographic systems
may be employed.
5.8.1 Example columns and operating conditions.
5.8.1.1 DB-608 (or equivalent), 30-m long x 0.53-mm ID fused-silica
capillary, 0.83-[micro]m film thickness.
5.8.1.2 DB-1701 (or equivalent), 30-m long x 0.53-mm ID fused-silica
capillary, 1.0-[micro]m film thickness.
5.8.1.3 Suggested operating conditions used to meet the retention
times shown in Table 3 are:
(a) Carrier gas flow rate: Approximately 7 mL/min,
(b) Initial temperature: 150 [deg]C for 0.5 minute,
(c) Temperature program: 150-270 [deg]C at 5 [deg]C/min, and
(d) Final temperature: 270 [deg]C, until trans-Permethrin elutes.
Note: Other columns, internal diameters, film thicknesses, and
operating conditions may be used, provided that the performance
requirements in this method are met. However, the column pair chosen
must have dissimilar phases/chemical properties in order to separate the
compounds of interest in different retention time order. Columns that
only differ in the length, ID, or film thickness, but use the same
stationary phase do not qualify as ``dissimilar.''
5.8.2 Carrier gas--Helium or hydrogen. Data in the tables in this
method were obtained using helium carrier gas. If hydrogen is used,
analytical conditions may need to be adjusted for optimum performance,
and calibration and all QC tests must be performed with hydrogen carrier
gas. See Section 4.3 for precautions regarding the use of hydrogen as a
carrier gas.
5.8.3 Detector--Halogen-specific detector (electron capture detector
[ECD], electrolytic conductivity detector [ELCD], or equivalent). The
ECD has proven effective in the analysis of wastewaters for the analytes
listed in Tables 1 and 2, and was used to develop the method performance
data in Section 17 and Tables 4 and 5.
5.8.4 Data system--A computer system must be interfaced to the GC
that allows continuous acquisition and storage of data from the
detectors throughout the chromatographic program. The computer must have
software that allows searching GC data for specific analytes, and for
plotting responses versus time. Software must also be available that
allows integrating peak areas or peak heights in selected retention time
windows and calculating concentrations of the analytes.
6. Reagents and Standards
6.1 pH adjustment.
6.1.1 Sodium hydroxide solutions.
6.1.1.1 Concentrated (10 M)--Dissolve 40 g of NaOH (ACS) in reagent
water and dilute to 100 mL.
6.1.1.2 Dilute (1 M)--Dissolve 40 g NaOH in 1 L of reagent water.
6.1.2 Sulfuric acid (1+1)--Slowly add 50 mL of
H2SO4 (ACS, sp. gr. 1.84) to 50 mL of reagent
water.
6.1.3 Hydrochloric acid--Reagent grade, 6 N.
6.2 Sodium thiosulfate--(ACS) granular.
6.3 Sodium sulfate--Sodium sulfate, reagent grade, granular
anhydrous (Baker or equivalent), rinsed with methylene chloride, baked
in a shallow tray at 450 [deg]C for 1 hour minimum, cooled in a
desiccator, and stored in a pre-cleaned glass bottle with screw cap
which prevents moisture from entering. If, after heating, the sodium
sulfate develops a noticeable grayish cast (due to the presence of
carbon in the crystal matrix), that batch of reagent is not suitable for
use and should be discarded. Extraction with methylene chloride (as
opposed to simple rinsing) and baking at a lower temperature may produce
sodium sulfate suitable for use.
6.4 Reagent water--Reagent water is defined as water in which the
analytes of interest and interfering compounds are not observed at the
MDLs of the analytes in this method.
6.5 Solvents--Methylene chloride, acetone, methanol, hexane,
acetonitrile, and isooctane, high purity pesticide quality, or
equivalent, demonstrated to be free of the analytes and interferences
(section 3). Purification of solvents by distillation in all-glass
systems may be required.
Note: The standards and final sample extracts must be prepared in
the same final solvent.
6.6 Ethyl ether--Nanograde, redistilled in glass if necessary. Ethyl
ether must be shown to be free of peroxides before use, as indicated by
EM Laboratories Quant test strips (available from Scientific Products
Co. and other suppliers). Procedures recommended for removal of
peroxides are provided with the test strips. After removal of peroxides,
add 20 mL of ethyl alcohol preservative to each liter of ether.
6.7 Materials for sample cleanup.
6.7.1 Florisil[supreg]--PR grade (60/100 mesh), activated at 650-700
[deg]C, stored in the dark in a glass container with fluoropolymer-lined
[[Page 162]]
screw cap. Activate each batch immediately prior to use for 16 hours
minimum at 130 [deg]C in a foil-covered glass container and allow to
cool. Alternatively, 500 mg cartridges (J.T. Baker, or equivalent) may
be used.
6.7.1.1 Cartridge certification--Each cartridge lot must be
certified to ensure recovery of the analytes of interest and removal of
2,4,6-trichlorophenol. To make the test mixture, add the trichlorophenol
solution (section 6.7.1.3) to the same standard used to prepare the
Quality Control Check Sample (section 6.8.3). Transfer the mixture to
the column and dry the column. Pre-elute with three 10-mL portions of
elution solvent, drying the column between elutions. Elute the cartridge
with 10 mL each of methanol and water, as in section 11.2.3.3.
6.7.1.2 Concentrate the eluant to per section 10.3.3, exchange to
isooctane or hexane per section 10.3.3, and inject 1.0 [micro]L of the
concentrated eluant into the GC using the procedure in section 12. The
recovery of all analytes (including the unresolved GC peaks) shall be
within the ranges for calibration verification (section 13.6 and Table
4), the recovery of trichlorophenol shall be less than 5%, and no peaks
interfering with the target analytes shall be detected. Otherwise the
Florisil cartridge is not performing properly and the cartridge lot
shall be rejected.
6.7.1.3 Florisil cartridge calibration solution--2,4,6-
Trichlorophenol, 0.1 [micro]g/mL in acetone.
6.7.2 SPE elution solvent--Methylene chloride:acetonitrile:hexane
(50:3:47).
6.7.3 Alumina, neutral, Brockman Activity I, 80-200 mesh (Fisher
Scientific certified, or equivalent). Heat in a glass bottle for 16
hours at 400 to 450 [deg]C. Seal and cool to room temperature. Add 7%
(w/w) reagent water and mix for 10 to 12 hours. Keep bottle tightly
sealed.
6.7.4 Sulfur removal.
6.7.4.1 Copper foil or powder--Fisher, Alfa Aesar, or equivalent.
Cut copper foil into approximately 1-cm squares. Copper must be
activated before it may be used, as described below.
6.7.4.1.1 Place the quantity of copper needed for sulfur removal
(section 11.5.1.3) in a ground-glass-stoppered Erlenmeyer flask or
bottle. Cover the foil or powder with methanol.
6.7.4.1.2 Add HCl dropwise (0.5-1.0 mL) while swirling, until the
copper brightens.
6.7.4.1.3 Pour off the methanol/HCl and rinse 3 times with reagent
water to remove all traces of acid, then 3 times with acetone, then 3
times with hexane.
6.7.4.1.4 For copper foil, cover with hexane after the final rinse.
Store in a stoppered flask under nitrogen until used. For the powder,
dry on a rotary evaporator. Store in a stoppered flask under nitrogen
until used. Inspect the copper foil or powder before each use. It must
have a bright, non-oxidized appearance to be effective. Copper foil or
powder that has oxidized may be reactivated using the procedure
described above.
6.7.4.2 Tetrabutylammonium sulfite (TBA sulfite)--Prepare as
described below.
6.7.4.2.1 Tetrabutylammonium hydrogen sulfate,
[CH3(CH2)3]4NHSO4.
6.7.4.2.2 Sodium sulfite, Na2SO3.
6.7.4.2.3 Dissolve approximately 3 g tetrabutylammonium hydrogen
sulfate in 100 mL of reagent water in an amber bottle with
fluoropolymer-lined screw cap. Extract with three 20-mL portions of
hexane and discard the hexane extracts.
6.7.4.2.4 Add 25 g sodium sulfite to produce a saturated solution.
Store at room temperature. Replace after 1 month.
6.7.5 Sodium chloride--Reagent grade, prepare at 5% (w/v) solution
in reagent water.
6.8 Stock standard solutions--Stock standard solutions may be
prepared from pure materials, or purchased as certified solutions.
Traceability must be to the National Institute of Standards and
Technology (NIST) or other national or international standard, when
available. Stock solution concentrations alternative to those below may
be used. Because of the toxicity of some of the compounds, primary
dilutions should be prepared in a hood, and a NIOSH/MESA approved toxic
gas respirator should be worn when high concentrations of neat materials
are handled. The following procedure may be used to prepare standards
from neat materials.
6.8.1 Accurately weigh about 0.0100 g of pure material in a 10-mL
volumetric flask. Dilute to volume in pesticide quality hexane,
isooctane, or other suitable solvent. Larger volumes may be used at the
convenience of the laboratory. When compound purity is assayed to be 96%
or greater, the weight may be used without correction to calculate the
concentration of the stock standard. Commercially prepared stock
standards may be used at any concentration if they are certified by the
manufacturer or by an independent source.
6.8.1.1 Unless stated otherwise in this method, store non-aqueous
standards in fluoropolymer-lined screw-cap, or heat-sealed, glass
containers, in the dark at -20 to -10 [deg]C. Store aqueous standards;
e.g., the aqueous LCS (section 8.4), in the dark at <=6 [deg]C, but do
not freeze.
6.8.1.2 Standards prepared by the laboratory may be stored for up to
one year, except when comparison with QC check standards indicates that
a standard has degraded or become more concentrated due to evaporation,
or unless the laboratory has data on file to prove stability for a
longer period. Commercially prepared standards may be stored until the
expiration date provided by the vendor, except when comparison with QC
check standards indicates that a standard
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has degraded or become more concentrated due to evaporation, or unless
the laboratory has data from the vendor on file to prove stability for a
longer period.
6.8.2 Calibration solutions--It is necessary to prepare calibration
solutions for the analytes of interest (section 1.4) only using an
appropriate solvent (isooctane or hexane may be used). Whatever solvent
is used, both the calibration standards and the final sample extracts
must use the same solvent. Other analytes may be included as desired.
6.8.2.1 Prepare calibration standards for the single-component
analytes of interest and surrogates at a minimum of three concentration
levels (five are suggested) by adding appropriate volumes of one or more
stock standards to volumetric flasks. One of the calibration standards
should be at a concentration at or below the ML specified in Table 1, or
2, or as specified by a regulatory/control authority or in a permit. The
ML value may be rounded to a whole number that is more convenient for
preparing the standard, but must not exceed the ML value listed in
Tables 1 or 2 for those analytes which list ML values. Alternatively,
the laboratory may establish an ML for each analyte based on the
concentration of the lowest calibration standard in a series of
standards produced by the laboratory or obtained from a commercial
vendor, again, provided that the ML does not exceed the ML in Table 1
and 2, and provided that the resulting calibration meets the acceptance
criteria in section 7.5.2 based on the RSD, RSE, or R\2\.
(a) The other concentrations should correspond to the expected range
of concentrations found in real samples or should define the working
range of the GC system. A minimum of six concentration levels is
required for a second order, non-linear (e.g., quadratic; ax\2\ + bx + c
= 0) calibration (section 7.5.2 or 7.6.2). Calibrations higher than
second order are not allowed. A separate standard near the MDL may be
analyzed as a check on sensitivity, but should not be included in the
linearity assessment. The solvent for the standards must match the final
solvent for the sample extracts (e.g., isooctane or hexane).
Note: The option for non-linear calibration may be necessary to
address specific instrumental techniques. However, it is not EPA's
intent to allow non-linear calibration to be used to compensate for
detector saturation or to avoid proper instrument maintenance.
(b) Given the number of analytes included in this method, it is
highly likely that some will coelute on one or both of the GC columns
used for the analysis. Divide the analytes into two or more groups and
prepare separate calibration standards for each group, at multiple
concentrations (e.g., a five-point calibration will require ten
solutions to cover two groups of analytes). Table 7 provides information
on dividing the target analytes into separate calibration mixtures that
should minimize or eliminate co-elutions. This table is provided solely
as guidance, based on the GC columns suggested in this method. If an
analyte listed in Table 7 is not an analyte of interest in a given
laboratory setting, then it need not be included in a calibration
mixture.
Note: Many commercially available standards are divided into
separate mixtures to address this issue.
(c) If co-elutions occur in analysis of a sample, a co-elution on
one column is acceptable so long as effective separation of the co-
eluting compounds can be achieved on the second column.
6.8.2.2 Multi-component analytes (e.g., PCBs as Aroclors, and
Toxaphene).
6.8.2.2.1 A standard containing a mixture of Aroclor 1016 and
Aroclor 1260 will include many of the peaks represented in the other
Aroclor mixtures. As a result, a multi-point initial calibration
employing a mixture of Aroclors 1016 and 1260 at three to five
concentrations should be sufficient to demonstrate the linearity of the
detector response without the necessity of performing multi-point
initial calibrations for each of the seven Aroclors. In addition, such a
mixture can be used as a standard to demonstrate that a sample does not
contain peaks that represent any one of the Aroclors. This standard can
also be used to determine the concentrations of either Aroclor 1016 or
Aroclor 1260, should they be present in a sample. Therefore, prepare a
minimum of three calibration standards containing equal concentrations
of both Aroclor 1016 and Aroclor 1260 by dilution of the stock standard
with isooctane or hexane. The concentrations should correspond to the
expected range of concentrations found in real samples and should
bracket the linear range of the detector.
6.8.2.2.2 Single standards of each of the other five Aroclors are
required to aid the analyst in pattern recognition. Assuming that the
Aroclor 1016/1260 standards described in Section 6.8.2.2.1 have been
used to demonstrate the linearity of the detector, these single
standards of the remaining five Aroclors also may be used to determine
the calibration factor for each Aroclor. Prepare a standard for each of
the other Aroclors. The concentrations should generally correspond to
the mid-point of the linear range of the detector, but lower
concentrations may be employed at the discretion of the analyst based on
project requirements.
6.8.2.2.3 For Toxaphene, prepare a minimum of three calibration
standards containing Toxaphene by dilution of the stock
[[Page 164]]
standard with isooctane or hexane. The concentrations should correspond
to the expected range of concentrations found in real samples and should
bracket the linear range of the detector.
6.8.3 Quality Control (QC) Check Sample Concentrate--Prepare one or
more mid-level standard mixtures (concentrates) in acetone (or other
water miscible solvent). The concentrate is used as the spiking solution
with which to prepare the Demonstration of Capabilities (DOC) samples,
the Laboratory Control Sample (LCS), and Matrix Spike (MS) and Matrix
Spike Duplicate (MSD) samples described in section 8. If prepared by the
laboratory (as opposed the purchasing it from a commercial supplier),
the concentrate must be prepared independently from the standards used
for calibration, but may be prepared from the same source as the second-
source standard used for calibration verification (section 7.7).
Regardless of the source, the concentrate must be in a water-miscible
solvent, as noted above. The concentrate is used to prepare the DOC and
LCS (sections 8.2.1 and 8.4) and MS/MSD samples (section 8.3). Depending
on the analytes of interest for a given sample (see Section 1.4),
multiple solutions and multiple LCS or MS/MSD samples may be required to
account for co-eluting analytes. However, a co-elution on one column is
acceptable so long as effective separation of the co-eluting compounds
can be achieved on the second column. In addition, the concentrations of
the MS/MSD samples should reflect any relevant compliance limits for the
analytes of interest, as described in section 8.3.1. If a custom spiking
solution is required for a specific discharge (section 8.3.1), prepare
it separately from the DOC and LCS solution.
Note: Some commercially available standards are divided into
separate mixtures to address the co-elution issue.
6.8.4 Calibration Verification Standards--In order to verify the
results of the initial calibration standards, prepare one or more mid-
level standard mixtures in isooctane or hexane, using standards obtained
from a second source (different manufacturer or different certified lot
from the calibration standards). These standards will be analyzed to
verify the accuracy of the calibration (sections 7.7 and 13.6.2). As
with the QC sample concentrate in section 6.8.3, multiple solutions may
be required to address co-elutions among all of the analytes.
6.8.5 Internal standard solution--If the internal standard
calibration technique is to be used, prepare pentachloronitrobenzene
(PCNB) at a concentration of 10 [micro]g/mL in ethyl acetate.
Alternative and multiple internal standards; e.g., tetrachloro-m-xylene,
4,4[min]-dibromobiphenyl, and/or decachlorobiphenyl may be used provided
that the laboratory performs all QC tests and meets all QC acceptance
criteria with the alternative or additional internal standard(s) as an
integral part of this method.
6.8.6 Surrogate solution--Prepare a solution containing one or more
surrogates at a concentration of 2 [micro]g/mL in acetone. Potential
surrogates include: dibutyl chlorendate (DBC), tetrachloro-m-xylene
(TCMX), 4,4[min]-dibromobiphenyl, or decachlorobiphenyl. Alternative
surrogates and concentrations may be used, provided the laboratory
performs all QC tests and meets all QC acceptance criteria with the
alternative surrogate(s) as an integral part of this method. If the
internal standard calibration technique is used, do not use the internal
standard as a surrogate.
6.8.7 DDT and endrin decomposition (breakdown) solution--Prepare a
solution containing endrin at a concentration of 50 ng/mL and 4,4'-DDT
at a concentration of 100 ng/mL, in isooctane or hexane. A 1-[micro]L
injection of this standard will contain 50 picograms (pg) of endrin and
100 pg of DDT. The concentration of the solution may be adjusted by the
laboratory to accommodate other injection volumes such that the same
masses of the two analytes are introduced into the instrument.
7. Calibration
7.1 Establish gas chromatographic operating conditions equivalent to
those in Section 5.8.1 and Footnote 2 to Table 3. Alternative
temperature program and flow rate conditions may be used. The system may
be calibrated using the external standard technique (section 7.5) or the
internal standard technique (section 7.6). It is necessary to calibrate
the system for the analytes of interest (section 1.4) only.
7.2 Separately inject the mid-level calibration standard for each
calibration mixture. Store the retention time on each GC column.
7.3 Injection of calibration solutions--Inject a constant volume in
the range of 0.5 to 2.0 [micro]L of each calibration solution into the
GC column/detector pairs. An alternative volume (see Section 12.3) may
be used provided all requirements in this method are met. Beginning with
the lowest level mixture and proceeding to the highest level mixture may
limit the risk of carryover from one standard to the next, but other
sequences may be used. An instrument blank should be analyzed after the
highest standard to demonstrate that there is no carry-over within the
system for this calibration range.
7.4 For each analyte, compute, record, and store, as a function of
the concentration injected, the retention time and peak area on each
column/detector system. If multi-component analytes are to be analyzed,
store the retention time and peak area for the three to five exclusive
(unique large) peaks
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for each PCB or technical chlordane. Use four to six peaks for
toxaphene.
7.5 External standard calibration.
7.5.1 From the calibration data (Section 7.4), calculate the
calibration factor (CF) for each analyte at each concentration according
to the following equation:
[GRAPHIC] [TIFF OMITTED] TR28AU17.000
Where:
Cs = Concentration of the analyte in the standard (ng/mL)
As = Peak height or area
For multi-component analytes, choose a series of characteristic
peaks for each analyte (3 to 5 for each Aroclor, 4 to 6 for toxaphene)
and calculate individual calibration factors for each peak.
Alternatively, for toxaphene, sum the areas of all of the peaks in the
standard chromatogram and use the summed area to determine the
calibration factor. (If this alternative is used, the same approach must
be used to quantitate the analyte in the samples.)
7.5.2 Calculate the mean (average) and relative standard deviation
(RSD) of the calibration factors. If the RSD is less than 20%, linearity
through the origin can be assumed and the average CF can be used for
calculations. Alternatively, the results can be used to fit a linear or
quadratic regression of response, As, vs. concentration
Cs. If used, the regression must be weighted inversely
proportional to concentration. The coefficient of determination (R\2\)
of the weighted regression must be greater than 0.920. Alternatively,
the relative standard error (Reference 10) may be used as an acceptance
criterion. As with the RSD, the RSE must be less than 20%. If an RSE
less than 20% cannot be achieved for a quadratic regression, system
performance is unacceptable and the system must be adjusted and re-
calibrated.
Note: Regression calculations are not included in this method
because the calculations are cumbersome and because many GC/ECD data
systems allow selection of weighted regression for calibration and
calculation of analyte concentrations.
7.6 Internal standard calibration.
7.6.1 From the calibration data (Section 7.4), calculate the
response factor (RF) for each analyte at each concentration according to
the following equation:
[GRAPHIC] [TIFF OMITTED] TR28AU17.001
Where:
As = Response for the analyte to be measured.
Ais = Response for the internal standard.
Cis = Concentration of the internal standard (ng/mL)
Cs = Concentration of the analyte to be measured (ng/mL).
7.6.2 Calculate the mean (average) and relative standard deviation
(RSD) of the response factors. If the RSD is less than 15%, linearity
through the origin can be assumed and the average RF can be used for
calculations. Alternatively, the results can be used to prepare a
calibration curve of response ratios, As/Ais, vs.
concentration ratios, Cs/Cis, for the analyte. A
minimum of six concentration levels is required for a non-linear (e.g.,
quadratic) regression. If used, the regression must be weighted
inversely proportional to concentration, and the coefficient of
determination of the weighted regression must be greater than 0.920.
Alternatively, the relative standard error (Reference 10) may be used as
an acceptance criterion. As with the RSD, the RSE must be less than 15%.
If an RSE less than 15% cannot be achieved for a quadratic regression,
system performance is unacceptable and the system must be adjusted and
re-calibrated.
7.7 The working calibration curve, CF, or RF must be verified
immediately after calibration and at the beginning and end of each 24-
hour shift by the analysis of a mid-level calibration standard. The
calibration verification standard(s) must be obtained from a second
manufacturer or a manufacturer's batch prepared independently from the
batch used for calibration (Section 6.8.4). Requirements for calibration
verification are given in Section 13.6 and Table 4. Alternatively,
calibration verification may be performed after a set number of
injections
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(e.g., every 20 injections), to include injection of extracts of field
samples, QC samples, instrument blanks, etc. (i.e., it is based on the
number of injections performed, not sample extracts). The time for the
injections may not exceed 24 hours.
Note: The 24-hour shift begins after analysis of the combined QC
standard (calibration verification) and ends 24 hours later. The ending
calibration verification standard is run immediately after the last
sample run during the 24-hour shift, so the beginning and ending
calibration verifications are outside of the 24-hour shift. If
calibration verification is based on the number of injections instead of
time, then the ending verification standard for one group of injections
may be used as the beginning verification for the next group of
injections.
7.8 Florisil[supreg] calibration--The column cleanup procedure in
Section 11.3 utilizes Florisil column chromatography. Florisil[supreg]
from different batches or sources may vary in adsorptive capacity. To
standardize the amount of Florisil[supreg] which is used, use of the
lauric acid value (Reference 11) is suggested. The referenced procedure
determines the adsorption from a hexane solution of lauric acid (mg) per
g of Florisil[supreg]. The amount of Florisil[supreg] to be used for
each column is calculated by dividing 110 by this ratio and multiplying
by 20 g. If cartridges containing Florisil[supreg] are used, then this
step is not necessary.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality assurance program. The minimum requirements of this
program consist of an initial demonstration of laboratory capability and
ongoing analysis of spiked samples and blanks to evaluate and document
data quality. The laboratory must maintain records to document the
quality of data generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet performance requirements of this method. A quality control check
standard (LCS, section 8.4) must be prepared and analyzed with each
batch of samples to confirm that the measurements were performed in an
in-control mode of operation. A laboratory may develop its own
performance criteria (as QC acceptance criteria), provided such criteria
are as or more restrictive than the criteria in this method.
8.1.1 The laboratory must make an initial demonstration of the
capability (IDC) to generate acceptable precision and recovery with this
method. This demonstration is detailed in Section 8.2. On a continuing
basis, the laboratory must repeat demonstration of capability (DOC) at
least annually.
8.1.2 In recognition of advances that are occurring in analytical
technology, and to overcome matrix interferences, the laboratory is
permitted certain options (section 1.8 and 40 CFR 136.6(b) [Reference
12]) to improve separations or lower the costs of measurements. These
options may include alternative extraction (e.g., other solid-phase
extraction materials and formats), concentration, and cleanup
procedures, and changes in GC columns (Reference 12). Alternative
determinative techniques, such as the substitution of spectroscopic or
immunoassay techniques, and changes that degrade method performance, are
not allowed. If an analytical technique other than the techniques
specified in this method is used, that technique must have a specificity
equal to or greater than the specificity of the techniques in this
method for the analytes of interest. The laboratory is also encouraged
to participate in performance evaluation studies (see section 8.8).
8.1.2.1 Each time a modification listed above is made to this
method, the laboratory is required to repeat the procedure in section
8.2. If the detection limit of the method will be affected by the
change, the laboratory is required to demonstrate that the MDLs (40 CFR
part 136, appendix B) are lower than one-third the regulatory compliance
limit or as low as the MDLs in this method, whichever are greater. If
calibration will be affected by the change, the instrument must be
recalibrated per section 7. Once the modification is demonstrated to
produce results equivalent or superior to results produced by this
method as written, that modification may be used routinely thereafter,
so long as the other requirements in this method are met (e.g., matrix
spike/matrix spike duplicate recovery and relative percent difference).
8.1.2.1.1 If an allowed method modification, is to be applied to a
specific discharge, the laboratory must prepare and analyze matrix
spike/matrix spike duplicate (MS/MSD) samples (section 8.3) and LCS
samples (section 8.4). The laboratory must include surrogates (Section
8.7) in each of the samples. The MS/MSD and LCS samples must be
fortified with the analytes of interest (section 1.4). If the
modification is for nationwide use, MS/MSD samples must be prepared from
a minimum of nine different discharges (See section 8.1.2.1.2), and all
QC acceptance criteria in this method must be met. This evaluation only
needs to be performed once other than for the routine QC required by
this method (for example it could be performed by the vendor of an
alternative material) but any laboratory using that specific material
must have the results of the study available. This includes a full data
package with the raw data that will allow an independent reviewer to
verify each determination and calculation performed by the laboratory
(see section 8.1.2.2.5, items (a)-(q)).
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8.1.2.1.2 Sample matrices on which MS/MSD tests must be performed
for nationwide use of an allowed modification:
(a) Effluent from a publicly owned treatment works (POTW).
(b) ASTM D5905 Standard Specification for Substitute Wastewater.
(c) Sewage sludge, if sewage sludge will be in the permit.
(d) ASTM D1141 Standard Specification for Substitute Ocean Water, if
ocean water will be in the permit.
(e) Untreated and treated wastewaters up to a total of nine matrix
types (see https://www.epa.gov/eg/industrial-effluent-guidelines for a
list of industrial categories with existing effluent guidelines).
(i) At least one of the above wastewater matrix types must have at
least one of the following characteristics:
(A) Total suspended solids greater than 40 mg/L.
(B) Total dissolved solids greater than 100 mg/L.
(C) Oil and grease greater than 20 mg/L.
(D) NaCl greater than 120 mg/L.
(E) CaCO3 greater than 140 mg/L.
(ii) The interim acceptance criteria for MS, MSD recoveries that do
not have recovery limits in Table 4 or developed in section 8.3.3, and
for surrogates that do not have recovery limits developed in section
8.6, must be no wider than 60-140%, and the relative percent difference
(RPD) of the concentrations in the MS and MSD that do not have RPD
limits in Table 4 or developed in section 8.3.3, must be less than 30%.
Alternatively, the laboratory may use the laboratory's in-house limits
if they are tighter.
(f) A proficiency testing (PT) sample from a recognized provider, in
addition to tests of the nine matrices (section 8.1.2.1.1).
8.1.2.2 The laboratory must maintain records of modifications made
to this method. These records include the following, at a minimum:
8.1.2.2.1 The names, titles, and business street addresses,
telephone numbers, and email addresses, of the analyst(s) that performed
the analyses and modification, and of the quality control officer that
witnessed and will verify the analyses and modifications.
8.1.2.2.2 A list of analytes, by name and CAS Registry number.
8.1.2.2.3 A narrative stating reason(s) for the modifications.
8.1.2.2.4 Results from all quality control (QC) tests comparing the
modified method to this method, including:
(a) Calibration (section 7).
(b) Calibration verification (section 13.6).
(c) Initial demonstration of capability (section 8.2).
(d) Analysis of blanks (section 8.5).
(e) Matrix spike/matrix spike duplicate analysis (section 8.3).
(f) Laboratory control sample analysis (section 8.4).
8.1.2.2.5 Data that will allow an independent reviewer to validate
each determination by tracing the instrument output (peak height, area,
or other signal) to the final result. These data are to include:
(a) Sample numbers and other identifiers.
(b) Extraction dates.
(c) Analysis dates and times.
(d) Analysis sequence/run chronology.
(e) Sample weight or volume (section 10).
(f) Extract volume prior to each cleanup step (sections 10 and 11).
(g) Extract volume after each cleanup step (section 11).
(h) Final extract volume prior to injection (sections 10 and 12).
(i) Injection volume (sections 12.3 and 13.2).
(j) Sample or extract dilution (section 15.4).
(k) Instrument and operating conditions.
(l) Column (dimensions, material, etc.).
(m) Operating conditions (temperatures, flow rates, etc.).
(n) Detector (type, operating conditions, etc.).
(o) Chromatograms and other recordings of raw data.
(p) Quantitation reports, data system outputs, and other data to
link the raw data to the results reported.
(q) A written Standard Operating Procedure (SOP).
8.1.2.2.6 Each individual laboratory wishing to use a given
modification must perform the start-up tests in section 8.1.2 (e.g.,
DOC, MDL), with the modification as an integral part of this method
prior to applying the modification to specific discharges. Results of
the DOC must meet the QC acceptance criteria in Table 5 for the analytes
of interest (section 1.4), and the MDLs must be equal to or lower than
the MDLs in Tables 1 and 2 for the analytes of interest.
8.1.3 Before analyzing samples, the laboratory must analyze a blank
to demonstrate that interferences from the analytical system, lab ware,
and reagents, are under control. Each time a batch of samples is
extracted or reagents are changed, a blank must be extracted and
analyzed as a safeguard against laboratory contamination. Requirements
for the blank are given in section 8.5.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze
samples to monitor and evaluate method and laboratory performance on the
sample matrix. The procedure for spiking and analysis is given in
section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
analysis of a quality control check sample (laboratory control sample,
LCS; on-going precision and
[[Page 168]]
recovery sample, OPR) that the measurement system is in control. This
procedure is described in Section 8.4.
8.1.6 The laboratory should maintain performance records to document
the quality of data that is generated. This procedure is given in
section 8.7.
8.1.7 The large number of analytes tested in performance tests in
this method present a substantial probability that one or more will fail
acceptance criteria when all analytes are tested simultaneously, and a
re-test (reanalysis) is allowed if this situation should occur. If,
however, continued re-testing results in further repeated failures, the
laboratory should document the failures and either avoid reporting
results for the analytes that failed or report the problem and failures
with the data. A QC failure does not relieve a discharger or permittee
of reporting timely results.
8.2 Demonstration of capability (DOC)--To establish the ability to
generate acceptable recovery and precision, the laboratory must perform
the DOC in sections 8.2.1 through 8.2.6 for the analytes of interest
initially and in an on-going manner at least annually. The laboratory
must also establish MDLs for the analytes of interest using the MDL
procedure at 40 CFR part 136, appendix B. The laboratory's MDLs must be
equal to or lower than those listed in Tables 1 or 2, or lower than one-
third the regulatory compliance limit, whichever is greater. For MDLs
not listed in Tables 1 or 2, the laboratory must determine the MDLs
using the MDL procedure at 40 CFR part 136, appendix B under the same
conditions used to determine the MDLs for the analytes listed in Tables
1 and 2. When analyzing the PCBs as Aroclors, it is only necessary to
establish an MDL for one of the multi-component analytes (e.g., PCB
1254), or the mixture of Aroclors 1016 and 1260 may be used to establish
MDLs for all of the Aroclors. Similarly, MDLs for other multi-component
analytes (e.g., Chlordanes) may be determined using only one of the
major components. All procedures used in the analysis, including cleanup
procedures, must be included in the DOC.
8.2.1 For the DOC, a QC check sample concentrate containing each
analyte of interest (section 1.4) is prepared in a water-miscible
solvent using the solution in section 6.8.3.
Note: QC check sample concentrates are no longer available from EPA.
8.2.2 Using a pipet or syringe, prepare four QC check samples by
adding an appropriate volume of the concentrate and of the surrogate(s)
to each of four 1-L aliquots of reagent water. Swirl or stir to mix.
8.2.3 Extract and analyze the well-mixed QC check samples according
to the method beginning in section 10.
8.2.4 Calculate the average percent recovery (X) and the standard
deviation (s) of the percent recovery for each analyte using the four
results.
8.2.5 For each analyte, compare s and X with the corresponding
acceptance criteria for precision and recovery in Table 4. For analytes
in Table 2 that are not listed in Table 4, QC acceptance criteria must
be developed by the laboratory. EPA has provided guidance for
development of QC acceptance criteria (References 12 and 13). If s and X
for all analytes of interest meet the acceptance criteria, system
performance is acceptable and analysis of blanks and samples can begin.
If any individual s exceeds the precision limit or any individual X
falls outside the range for recovery, system performance is unacceptable
for that analyte.
Note: The large number of analytes in Tables 1 and 2 present a
substantial probability that one or more will fail at least one of the
acceptance criteria when many or all analytes are determined
simultaneously.
8.2.6 When one or more of the analytes tested fail at least one of
the acceptance criteria, repeat the test for only the analytes that
failed. If results for these analytes pass, system performance is
acceptable and analysis of samples and blanks may proceed. If one or
more of the analytes again fail, system performance is unacceptable for
the analytes that failed the acceptance criteria. Correct the problem
and repeat the test (section 8.2). See section 8.1.7 for disposition of
repeated failures.
Note: To maintain the validity of the test and re-test, system
maintenance and/or adjustment is not permitted between this pair of
tests.
8.3 Matrix spike and matrix spike duplicate (MS/MSD)--The purpose of
the MS/MSD requirement is to provide data that demonstrate the
effectiveness of the method as applied to the samples in question by a
given laboratory, and both the data user (discharger, permittee,
regulated entity, regulatory/control authority, customer, other) and the
laboratory share responsibility for provision of such data. The data
user should identify the sample and the analytes of interest (section
1.4) to be spiked and provide sufficient sample volume to perform MS/MSD
analyses. The laboratory must, on an ongoing basis, spike at least 5% of
the samples in duplicate from each discharge being monitored to assess
accuracy (recovery and precision). If direction cannot be obtained from
the data user, the laboratory must spike at least one sample in
duplicate per extraction batch of up to 20 samples with the analytes in
Table 1. Spiked sample results should be reported only to the data user
whose sample was spiked, or as requested or required by a regulatory/
control authority, or in a permit.
8.3.1. If, as in compliance monitoring, the concentration of a
specific analyte will be
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checked against a regulatory concentration limit, the concentration of
the spike should be at that limit; otherwise, the concentration of the
spike should be one to five times higher than the background
concentration determined in section 8.3.2, at or near the midpoint of
the calibration range, or at the concentration in the LCS (section 8.4)
whichever concentration would be larger. When no information is
available, the mid-point of the calibration may be used.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of the each analyte of interest. If necessary to meet
the requirement in section 8.3.1, prepare a new check sample concentrate
(section 8.2.1) appropriate for the background concentration. Spike and
analyze two additional sample aliquots of the same volume as the
original sample, and determine the concentrations after spiking
(A1 and A2) of each analyte. Calculate the percent
recoveries (P1 and P2) as:
[GRAPHIC] [TIFF OMITTED] TR28AU17.002
where T is the known true value of the spike.
Also calculate the relative percent difference (RPD) between the
concentrations (A1 and A2):
[GRAPHIC] [TIFF OMITTED] TR28AU17.003
8.3.3 Compare the percent recoveries (P1 and
P2) and the RPD for each analyte in the MS/MSD aliquots with
the corresponding QC acceptance criteria for recovery (P) and RPD in
Table 4.
(a) If any individual P falls outside the designated range for
recovery in either aliquot, or the RPD limit is exceeded, the result for
the analyte in the unspiked sample is suspect and may not be reported or
used for permitting or regulatory compliance. See section 8.1.7 for
disposition of failures.
(b) For analytes in Table 2 not listed in Table 4, QC acceptance
criteria must be developed by the laboratory. EPA has provided guidance
for development of QC acceptance criteria (References 12 and 13).
8.3.4 After analysis of a minimum of 20 MS/MSD samples for each
target analyte and surrogate, and if the laboratory chooses to develop
and apply optional in-house QC limits, the laboratory should calculate
and apply the optional in-house QC limits for recovery and RPD of future
MS/MSD samples (Section 8.3). The optional in-house QC limits for
recovery are calculated as the mean observed recovery 3 standard deviations, and the upper QC limit for RPD is
calculated as the mean RPD plus 3 standard deviations of the RPDs. The
in-house QC limits must be updated at least every two years and re-
established after any major change in the analytical instrumentation or
process. At least 80% of the analytes tested in the MS/MSD must have in-
house QC acceptance criteria that are tighter than those in Table 4 and
the remaining analytes (those not included in the 80%) must meet the
acceptance criteria in Table 4. If an in-house QC limit for the RPD is
greater than the limit in Table 4, then the limit in Table 4 must be
used. Similarly, if an in-house lower limit for recovery is below the
lower limit in Table 4, then the lower limit in Table 4 must be used,
and if an in-house upper limit for recovery is above the upper limit in
Table 4, then the upper limit in Table 4 must be used. The laboratory
must evaluate surrogate recovery data in each sample against its in-
house surrogate recovery limits. The laboratory may use 60 -140% as
interim acceptance criteria for surrogate recoveries until in-house
limits are developed. Alternatively, surrogate recovery limits may be
developed from laboratory control charts. In-house QC acceptance
criteria must be updated at least every two years.
8.4 Laboratory control sample (LCS)--A QC check sample (laboratory
control sample, LCS; on-going precision and recovery sample, OPR)
containing each single-component analyte of interest (section 1.4) must
be extracted, concentrated, and analyzed with each extraction batch of
up to 20 samples (section 3.1) to demonstrate acceptable recovery of the
analytes of interest from a
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clean sample matrix. If multi-peak analytes are required, extract and
prepare at least one as an LCS for each batch. Alternatively, the
laboratory may set up a program where multi-peak LCS is rotated with a
single-peak LCS.
8.4.1 Prepare the LCS by adding QC check sample concentrate
(sections 6.8.3 and 8.2.1) to reagent water. Include all analytes of
interest (section 1.4) in the LCS. The volume of reagent water must be
the same as the nominal volume used for the sample, the DOC (Section
8.2), the blank (section 8.5), and the MS/MSD (section 8.3). Also add a
volume of the surrogate solution (section 6.8.6).
8.4.2 Analyze the LCS prior to analysis of samples in the extraction
batch (Section 3.1). Determine the concentration (A) of each analyte.
Calculate the percent recovery as:
[GRAPHIC] [TIFF OMITTED] TR28AU17.004
where T is the true value of the concentration in the LCS.
8.4.3 For each analyte, compare the percent recovery (P) with its
corresponding QC acceptance criterion in Table 4. For analytes of
interest in Table 2 not listed in Table 4, use the QC acceptance
criteria developed for the MS/MSD (section 8.3.3.2), or limits based on
laboratory control charts. If the recoveries for all analytes of
interest fall within the designated ranges, analysis of blanks and field
samples may proceed. If any individual recovery falls outside the range,
proceed according to section 8.4.4.
Note: The large number of analytes in Tables 1 and 2 present a
substantial probability that one or more will fail the acceptance
criteria when all analytes are tested simultaneously. Because a re-test
is allowed in event of failure (sections 8.1.7 and 8.4.4), it may be
prudent to extract and analyze two LCSs together and evaluate results of
the second analysis against the QC acceptance criteria only if an
analyte fails the first test.
8.4.4 Repeat the test only for those analytes that failed to meet
the acceptance criteria (P). If these analytes now pass, system
performance is acceptable and analysis of blanks and samples may
proceed. Repeated failure, however, will confirm a general problem with
the measurement system. If this occurs, repeat the test using a fresh
LCS (section 8.2.1) or an LCS prepared with a fresh QC check sample
concentrate (section 8.2.1), or perform and document system repair.
Subsequent to analysis of the LCS prepared with a fresh sample
concentrate, or to system repair, repeat the LCS test (Section 8.4). If
failure of the LCS indicates a systemic problem with samples in the
batch, re-extract and re-analyze the samples in the batch. See Section
8.1.7 for disposition of repeated failures.
8.4.5 After analysis of 20 LCS samples, and if the laboratory
chooses to develop and apply optional in-house QC limits, the laboratory
should calculate and apply the optional in-house QC limits for recovery
of future LCS samples (section 8.4). Limits for recovery in the LCS
should be calculated as the mean recovery 3
standard deviations. A minimum of 80% of the analytes tested for in the
LCS must have QC acceptance criteria tighter than those in Table 4, and
the remaining analytes (those not included in the 80%) must meet the
acceptance criteria in Table 4. If an in-house lower limit for recovery
is lower than the lower limit in Table 4, the lower limit in Table 4
must be used, and if an in-house upper limit for recovery is higher than
the upper limit in Table 4, the upper limit in Table 4 must be used.
Many of the analytes and surrogates do not contain acceptance criteria.
The laboratory should use 60-140% as interim acceptance criteria for
recoveries of spiked analytes and surrogates that do not have recovery
limits specified in Table 4, and at least 80% of the surrogates must
meet the 60-140% interim criteria until in-house LCS and surrogate
limits are developed. Alternatively, acceptance criteria for analytes
that do not have recovery limits in Table 4 may be based on laboratory
control charts. In-house QC acceptance criteria must be updated at least
every two years.
8.5 Blank--Extract and analyze a blank with each extraction batch
(section 3.1) to demonstrate that the reagents and equipment used for
preparation and analysis are free from contamination.
8.5.1 Prepare the blank from reagent water and spike it with the
surrogates. The volume of reagent water must be the same as the volume
used for samples, the DOC (section 8.2), the LCS (section 8.4), and the
MS/MSD (section 8.3). Extract, concentrate, and analyze the blank using
the same procedures and reagents used for the samples, LCS, and MS/MSD
in the batch. Analyze the blank immediately after analysis of the LCS
(section 8.4) and prior to analysis of the MS/MSD and samples to
demonstrate freedom from contamination.
8.5.2 If any analyte of interest is found in the blank at a
concentration greater than the MDL for the analyte, at a concentration
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greater than one-third the regulatory compliance limit, or at a
concentration greater than one-tenth the concentration in a sample in
the batch (section 3.1), whichever is greatest, analysis of samples must
be halted and samples in the batch must be re-extracted and the extracts
reanalyzed. Samples in a batch must be associated with an uncontaminated
blank before the results for those samples may be reported or used for
permitting or regulatory compliance purposes. If re-testing of blanks
results in repeated failures, the laboratory should document the
failures and report the problem and failures with the data.
8.6 Surrogate recovery--The laboratory must spike all samples with
the surrogate standard spiking solution (section 6.8.6) per section
10.2.2 or 10.4.2, analyze the samples, and calculate the percent
recovery of each surrogate. QC acceptance criteria for surrogates must
be developed by the laboratory (section 8.4). If any recovery fails its
criterion, attempt to find and correct the cause of the failure, and if
sufficient volume is available, re-extract another aliquot of the
affected sample; otherwise, see section 8.1.7 for disposition of
repeated failures.
8.7 As part of the QC program for the laboratory, it is suggested
but not required that method accuracy for wastewater samples be assessed
and records maintained. After analysis of five or more spiked wastewater
samples as in Section 8.3, calculate the average percent recovery (X)
and the standard deviation of the percent recovery (sp). Express the
accuracy assessment as a percent interval from X-2sp to X+2sp. For
example, if X = 90% and sp = 10%, the accuracy interval is expressed as
70-110%. Update the accuracy assessment for each analyte on a regular
basis to ensure process control (e.g., after each 5-10 new accuracy
measurements). If desired, statements of accuracy for laboratory
performance, independent of performance on samples, may be developed
using LCSs.
8.8 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as gas chromatography with another dissimilar column, specific
element detector, or mass spectrometer must be used. Whenever possible,
the laboratory should analyze standard reference materials and
participate in relevant performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Collect samples as grab samples in glass bottles, or in
refrigerated bottles using automatic sampling equipment. Collect 1-L of
ambient waters, effluents, and other aqueous samples. If high
concentrations of the analytes of interest are expected (e.g., for
untreated effluents or in-process waters), collect a smaller volume
(e.g., 250 mL), but not less than 100 mL, in addition to the 1-L sample.
Follow conventional sampling practices, except do not pre-rinse the
bottle with sample before collection. Automatic sampling equipment must
be as free as possible of polyvinyl chloride or other tubing or other
potential sources of contamination. If needed, collect additional
sample(s) for the MS/MSD (section 8.3).
9.2 Ice or refrigerate the sample at <=6 [deg]C from the time of
collection until extraction, but do not freeze. If aldrin is to be
determined and residual chlorine is present, add 80 mg/L of sodium
thiosulfate but do not add excess. Any method suitable for field use may
be employed to test for residual chlorine (Reference 14). If sodium
thiosulfate interferes in the determination of the analytes, an
alternative preservative (e.g., ascorbic acid or sodium sulfite) may be
used.
9.3 Extract all samples within seven days of collection and
completely analyze within 40 days of extraction (Reference 1). If the
sample will not be extracted within 72 hours of collection, adjust the
sample pH to a range of 5.0-9.0 with sodium hydroxide solution or
sulfuric acid. Record the volume of acid or base used.
10. Sample Extraction
10.1 This section contains procedures for separatory funnel liquid-
liquid extraction (SFLLE, section 10.2), continuous liquid-liquid
extraction (CLLE, section 10.4), and disk-based solid-phase extraction
(SPE, section 10.5). SFLLE is faster, but may not be as effective as
CLLE for extracting polar analytes. SFLLE is labor intensive and may
result in formation of emulsions that are difficult to break. CLLE is
less labor intensive, avoids emulsion formation, but requires more time
(18-24 hours), more hood space, and may require more solvent. SPE can be
faster, unless the particulate load in an aqueous sample is so high that
it slows the filtration process. If an alternative extraction scheme to
those detailed in this method is used, all QC tests must be performed
and all QC acceptance criteria must be met with that extraction scheme
as an integral part of this method.
10.2 Separatory funnel liquid-liquid extraction (SFLLE).
10.2.1 The SFLLE procedure below assumes a sample volume of 1 L.
When a different sample volume is extracted, adjust the volume of
methylene chloride accordingly.
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10.2.2 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Pour the entire sample into the
separatory funnel. Pipet the surrogate standard spiking solution
(section 6.8.6) into the separatory funnel. If the sample will be used
for the LCS or MS or MSD, pipet the appropriate QC check sample
concentrate (section 8.3 or 8.4) into the separatory funnel. Mix well.
If the sample arrives in a larger sample bottle, 1 L may be measured in
a graduated cylinder, then added to the separatory funnel.
Note: Instances in which the sample is collected in an oversized
bottle should be reported by the laboratory to the data user. Of
particular concern is that fact that this practice precludes rinsing the
empty bottle with solvent as described below, which could leave
hydrophobic pesticides on the wall of the bottle, and underestimate the
actual sample concentrations.
10.2.3 Add 60 mL of methylene chloride to the sample bottle, seal,
and shake for 30 seconds to rinse the inner surface. Transfer the
solvent to the separatory funnel and extract the sample by shaking the
funnel for two minutes with periodic venting to release excess pressure.
Allow the organic layer to separate from the water phase for a minimum
of 10 minutes. If an emulsion forms and the emulsion interface between
the layers is more than one-third the volume of the solvent layer,
employ mechanical techniques to complete the phase separation. The
optimum technique depends upon the sample, but may include stirring,
filtration of the emulsion through glass wool, use of phase-separation
paper, centrifugation, salting, freezing, or other physical methods.
Collect the methylene chloride extract in a flask. If the emulsion
cannot be broken (recovery of less than 80% of the methylene chloride,
corrected for the water solubility of methylene chloride), transfer the
sample, solvent, and emulsion into the extraction chamber of a
continuous extractor and proceed as described in section 10.4.
10.2.4 Add a second 60-mL volume of methylene chloride to the sample
bottle and repeat the extraction procedure a second time, combining the
extracts in the flask. Perform a third extraction in the same manner.
Proceed to macro-concentration (section 10.3.1).
10.2.5 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to an appropriately sized
graduated cylinder. Record the sample volume to the nearest 5 mL. Sample
volumes may also be determined by weighing the container before and
after extraction or filling to the mark with water.
10.3 Concentration.
10.3.1 Macro concentration.
10.3.1.1 Assemble a Kuderna-Danish (K-D) concentrator by attaching a
10-mL concentrator tube to a 500-mL evaporative flask. Other
concentration devices or techniques may be used in place of the K-D
concentrator so long as the requirements of section 8.2 are met.
10.3.1.2 Pour the extract through a solvent-rinsed drying column
containing about 10 cm of anhydrous sodium sulfate, and collect the
extract in the K-D concentrator. Rinse the flask and column with 20-30
mL of methylene chloride to complete the quantitative transfer.
10.3.1.3 If no cleanup is to be performed on the sample, add 500
[micro]L (0.5 mL) of isooctane to the extract to act as a keeper during
concentration.
10.3.1.4 Add one or two clean boiling chips and attach a three-ball
Snyder column to the K-D evaporative flask. Pre-wet the Snyder column by
adding about 1 mL of methylene chloride to the top. Place the K-D
apparatus on a hot water bath (60-65 [deg]C) so that the concentrator
tube is partially immersed in the hot water, and the entire lower
rounded surface of the flask is bathed with hot vapor. Adjust the
vertical position of the apparatus and the water temperature as required
to complete the concentration in 15-20 minutes. At the proper rate of
evaporation the balls of the column will actively chatter but the
chambers will not flood with condensed solvent. When the apparent volume
of liquid reaches 1 mL or other determined amount, remove the K-D
apparatus from the water bath and allow it to drain and cool for at
least 10 minutes.
10.3.1.5 If the extract is to be cleaned up by sulfur removal or
acid back extraction, remove the Snyder column and rinse the flask and
its lower joint into the concentrator tube with 1 to 2 mL of methylene
chloride. A 5-mL syringe is recommended for this operation. Adjust the
final volume to 10 mL in methylene chloride and proceed to sulfur
removal (section 11.5) or acid back extraction (section 11.6). If the
extract is to cleaned up using one of the other cleanup procedures or is
to be injected into the GC, proceed to Kuderna-Danish micro-
concentration (section 10.3.2) or nitrogen evaporation and solvent
exchange (section 10.3.3).
10.3.2 Kuderna-Danish micro concentration--Add another one or two
clean boiling chips to the concentrator tube and attach a two-ball
micro-Snyder column. Pre-wet the Snyder column by adding about 0.5 mL of
methylene chloride to the top. Place the K-D apparatus on a hot water
bath (60-65 [deg]C) so that the concentrator tube is partially immersed
in hot water. Adjust the vertical position of the apparatus and the
water temperature as required to complete the concentration in 5-10
minutes. At the proper rate of distillation the balls of the column will
actively chatter but the chambers will not flood with condensed solvent.
When the
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apparent volume of liquid reaches approximately 1 mL or other required
amount, remove the K-D apparatus from the water bath and allow it to
drain and cool for at least 10 minutes. Remove the Snyder column and
rinse the flask and its lower joint into the concentrator tube with
approximately 0.2 mL of methylene chloride, and proceed to section
10.3.3 for nitrogen evaporation and solvent exchange.
10.3.3 Nitrogen evaporation and solvent exchange--Extracts to be
subjected to solid-phase cleanup (SPE) are exchanged into 1.0 mL of the
SPE elution solvent (section 6.7.2.2). Extracts to be subjected to
Florisil[supreg] or alumina cleanups are exchanged into hexane. Extracts
that have been cleaned up and are ready for analysis are exchanged into
isooctane or hexane, to match the solvent used for the calibration
standards.
10.3.3.1 Transfer the vial containing the sample extract to the
nitrogen evaporation (blowdown) device (section 5.2.5.2). Lower the vial
into a 50-55 [deg]C water bath and begin concentrating. During the
solvent evaporation process, do not allow the extract to become dry.
Adjust the flow of nitrogen so that the surface of the solvent is just
visibly disturbed. A large vortex in the solvent may cause analyte loss.
10.3.3.2 Solvent exchange.
10.3.3.2.1 When the volume of the liquid is approximately 500
[micro]L, add 2 to 3 mL of the desired solvent (SPE elution solvent for
SPE cleanup, hexane for Florisil or alumina, or isooctane for final
injection into the GC) and continue concentrating to approximately 500
[micro]L. Repeat the addition of solvent and concentrate once more.
10.3.3.3.2 Adjust the volume of an extract to be cleaned up by SPE,
Florisil[supreg], or alumina to 1.0 mL. Proceed to extract cleanup
(section 11).
10.3.3.3 Extracts that have been cleaned up and are ready for
analysis--Adjust the final extract volume to be consistent with the
volume extracted and the sensitivity desired. The goal is for a full-
volume sample (e.g., 1-L) to have a final extract volume of 10 mL, but
other volumes may be used.
10.3.4 Transfer the concentrated extract to a vial with
fluoropolymer-lined cap. Seal the vial and label with the sample number.
Store in the dark at room temperature until ready for GC analysis. If GC
analysis will not be performed on the same day, store the vial in the
dark at <=6 [deg]C. Analyze the extract by GC per the procedure in
section 12.
10.4 Continuous liquid/liquid extraction (CLLE).
10.4.1 Use CLLE when experience with a sample from a given source
indicates an emulsion problem, or when an emulsion is encountered using
SFLLE. CLLE may be used for all samples, if desired.
10.4.2 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Transfer the sample to the
continuous extractor and, using a pipet, add surrogate standard spiking
solution. If the sample will be used for the LCS, MS, or MSD, pipet the
appropriate check sample concentrate (section 8.2.1 or 8.3.2) into the
separatory funnel. Mix well. Add 60 mL of methylene chloride to the
sample bottle, seal, and shake for 30 seconds to rinse the inner
surface. Transfer the solvent to the extractor.
10.4.3 Repeat the sample bottle rinse with two additional 50-100 mL
portions of methylene chloride and add the rinses to the extractor.
10.4.4 Add a suitable volume of methylene chloride to the distilling
flask (generally 200-500 mL) and sufficient reagent water to ensure
proper operation of the extractor, and extract the sample for 18-24
hours. A shorter or longer extraction time may be used if all QC
acceptance criteria are met. Test and, if necessary, adjust the pH of
the water to a range of 5.0-9.0 during the second or third hour of the
extraction. After extraction, allow the apparatus to cool, then detach
the distilling flask. Dry, concentrate, solvent exchange, and transfer
the extract to a vial with fluoropolymer-lined cap, per Section 10.3.
10.4.5 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to an appropriately sized
graduated cylinder. Record the sample volume to the nearest 5 mL. Sample
volumes may also be determined by weighing the container before and
after extraction or filling to the mark with water.
10.5 Solid-phase extraction of aqueous samples. The steps in this
section address the extraction of aqueous field samples using disk-based
solid-phase extraction (SPE) media, based on an ATP approved by EPA in
1995 (Reference 20). This application of SPE is distinct from that used
in this method for the cleanup of sample extracts in section 11.2.
Analysts must be careful not to confuse the equipment, supplies, or the
procedural steps from these two different uses of SPE.
Note: Changes to the extraction conditions described below may be
made by the laboratory under the allowance for method flexibility
described in section 8.1, provided that the performance requirements in
section 8.2 are met. However, changes in SPE materials, formats, and
solvents must meet the requirements in section 8.1.2 and its
subsections.
10.5.1 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. If the sample contains
particulates, let stand to settle out the particulates before
extraction.
10.5.2 Extract the sample as follows:
10.5.2.1 Place a 90-mm standard filter apparatus on a vacuum
filtration flask or manifold and attach to a vacuum source. The vacuum
gauge must read at least 25 in. of
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mercury when all valves are closed. Position a 90-mm C18 extraction disk
onto the filter screen. Wet the entire disk with methanol. To aid in
filtering samples with particulates, a 1-[micro]m glass fiber filter or
Empore[supreg] Filter Aid 400 can be placed on the top of the disk and
wetted with methanol. Install the reservoir and clamp. Resume vacuum to
dry the disk. Interrupt the vacuum. Wash the disk and reservoir with 20
mL of methylene chloride. Resume the vacuum briefly to pull methylene
chloride through the disk. Interrupt the vacuum and allow the disk to
soak for about a minute. Resume vacuum and completely dry the disk.
10.5.2.2 Condition the disk with 20 mL of methanol. Apply vacuum
until nearly all the solvent has passed through the disk, interrupting
it while solvent remains on the disk. Allow the disk to soak for about a
minute. Resume vacuum to pull most of the methanol through, but
interrupting it to leave a layer of methanol on the surface of the disk.
Do not allow disk to dry. For uniform flow and good recovery, it is
critical the disk not be allowed to dry from now until the end of the
extraction. Discard waste solvent. Rinse the disk with 20 mL of
deionized water. Resume vacuum to pull most of the water through, but
interrupt it to leave a layer of water on the surface of the disk. Do
not allow the disk to dry. If disk does dry, recondition with methanol
as above.
10.5.2.3 Add the water sample to the reservoir and immediately apply
the vacuum. If particulates have settled in the sample, gently decant
the clear layer into the apparatus until most of the sample has been
processed. Then pour the remainder including the particulates into the
reservoir. Empty the sample bottle completely. When the filtration is
complete, dry the disk for three minutes. Turn off the vacuum.
10.5.3 Discard sample filtrate. Insert tube to collect the eluant.
The tube should fit around the drip tip of the base. Reassemble the
apparatus. Add 5.0 mL of acetone to the center of the disk, allowing it
to spread evenly over the disk. Turn the vacuum on and quickly off when
the filter surface nears dryness but still remains wet. Allow to soak
for 15 seconds. Add 20 mL of methylene chloride to the sample bottle,
seal and shake to rinse the inside of the bottle. Transfer the methylene
chloride from the bottle to the filter. Resume the vacuum slowly so as
to avoid splashing.
Interrupt the vacuum when the filter surface nears dryness but still
remains wet. Allow disk to soak in solvent for 20 seconds. Rinse the
reservoir glass and disk with 10 mL of methylene chloride. Resume vacuum
slowly. Interrupt vacuum when disk is covered with solvent. Allow to
soak for 20 seconds. Resume vacuum to dry the disk. Remove the sample
tube.
10.5.4 Dry, concentrate, solvent exchange, and transfer the extract
to a vial with fluoropolymer-lined cap, per section 10.3.
10.5.5 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to an appropriately sized
graduated cylinder. Record the sample volume to the nearest 5 mL. Sample
volumes may also be determined by weighing the container before and
after extraction or filling to the mark with water.
11. Extract Cleanup
11.1 Cleanup may not be necessary for relatively clean samples
(e.g., treated effluents, groundwater, drinking water). If particular
circumstances require the use of a cleanup procedure, the laboratory may
use any or all of the procedures below or any other appropriate
procedure (e.g., gel permeation chromatography). However, the laboratory
must first repeat the tests in sections 8.2, 8.3, and 8.4 to demonstrate
that the requirements of those sections can be met using the cleanup
procedure(s) as an integral part of this method. This is particularly
important when the target analytes for the analysis include any of the
single component pesticides in Table 2, because some cleanups have not
been optimized for all of those analytes.
11.1.1 The solid-phase cartridge (section 11.2) removes polar
organic compounds such as phenols.
11.1.2 The Florisil[supreg] column (section 11.3) allows for
selected fractionation of the organochlorine analytes and will also
eliminate polar interferences.
11.1.3 Alumina column cleanup (section 11.4) also removes polar
materials.
11.1.4 Elemental sulfur, which interferes with the electron capture
gas chromatography of some of the pesticides, may be removed using
activated copper, or TBA sulfite. Sulfur removal (section 11.5) is
required when sulfur is known or suspected to be present. Some
chlorinated pesticides which also contain sulfur may be removed by this
cleanup.
11.1.5 Acid back extraction (section 11.6) may be useful for cleanup
of PCBs and other compounds not adversely affected by sulfuric acid.
11.2 Solid-phase extraction (SPE) as a cleanup. In order to use the
C18 SPE cartridge in section 5.5.3.5 as a cleanup procedure, the sample
extract must be exchanged from methylene chloride to methylene
chloride:acetonitrile:hexane (50:3:47). Follow the solvent exchange
steps in section 10.3.3.2 prior to attempting solid-phase cleanup.
Note: This application of SPE is distinct from that used in this
method for the extraction of aqueous samples in section 10.5. Analysts
must be careful not to confuse the equipment, supplies, or procedural
steps from these two different uses of SPE.
[[Page 175]]
11.2.1 Setup.
11.2.1.1 Attach the VacElute Manifold (section 5.5.3.2) to a water
aspirator or vacuum pump with the trap and gauge installed between the
manifold and vacuum source.
11.2.1.2 Place the SPE cartridges in the manifold, turn on the
vacuum source, and adjust the vacuum to 5 to 10 psi.
11.2.2 Cartridge washing--Pre-elute each cartridge prior to use
sequentially with 10-mL portions each of hexane, methanol, and water
using vacuum for 30 seconds after each eluting solvent. Follow this pre-
elution with 1 mL methylene chloride and three 10-mL portions of the
elution solvent (section 6.7.2.2) using vacuum for 5 minutes after each
eluting solvent. Tap the cartridge lightly while under vacuum to dry
between solvent rinses. The three portions of elution solvent may be
collected and used as a cartridge blank, if desired. Finally, elute the
cartridge with 10 mL each of methanol and water, using the vacuum for 30
seconds after each eluant.
11.2.3 Extract cleanup.
11.2.3.1 After cartridge washing (section 11.2.2), release the
vacuum and place the rack containing the 50-mL volumetric flasks
(section 5.5.3.4) in the vacuum manifold. Re-establish the vacuum at 5
to 10 psi.
11.2.3.2 Using a pipette or a 1-mL syringe, transfer 1.0 mL of
extract to the SPE cartridge. Apply vacuum for five minutes to dry the
cartridge. Tap gently to aid in drying.
11.2.3.3 Elute each cartridge into its volumetric flask sequentially
with three 10-mL portions of the methylene chloride:acetonitrile:hexane
(50:3:47) elution solvent (section 6.7.2.2), using vacuum for five
minutes after each portion. Collect the eluants in the 50-mL volumetric
flasks.
11.2.3.4 Release the vacuum and remove the 50-mL volumetric flasks.
11.2.3.5 Concentrate the eluted extracts per Section 10.3.
11.3 Florisil[supreg]. In order to use Florisil cleanup, the sample
extract must be exchanged from methylene chloride to hexane. Follow the
solvent exchange steps in section 10.3.3.2 prior to attempting
Florisil[supreg] cleanup.
Note: Alternative formats for this cleanup may be used by the
laboratory, including cartridges containing Florisil[supreg]. If an
alternative format is used, consult the manufacturer's instructions and
develop a formal documented procedure to replace the steps in section
11.3 of this method and demonstrate that the alternative meets the
relevant quality control requirements of this method.
11.3.1 If the chromatographic column does not contain a frit at the
bottom, place a small plug of pre-cleaned glass wool in the column
(section 5.2.4) to retain the Florisil[supreg]. Place the mass of
Florisil[supreg] (nominally 20 g) predetermined by calibration (section
7.8 and Table 6) in a chromatographic column. Tap the column to settle
the Florisil[supreg] and add 1 to 2 cm of granular anhydrous sodium
sulfate to the top.
11.3.2 Add 60 mL of hexane to wet and rinse the sodium sulfate and
Florisil[supreg]. Just prior to exposure of the sodium sulfate layer to
the air, stop the elution of the hexane by closing the stopcock on the
chromatographic column. Discard the eluant.
11.3.3 Transfer the concentrated extract (section 10.3.3) onto the
column. Complete the transfer with two 1-mL hexane rinses, drawing the
extract and rinses down to the level of the sodium sulfate.
11.3.4 Place a clean 500-mL K-D flask and concentrator tube under
the column. Elute Fraction 1 with 200 mL of 6% (v/v) ethyl ether in
hexane at a rate of approximately 5 mL/min. Remove the K-D flask and set
it aside for later concentration. Elute Fraction 2 with 200 mL of 15%
(v/v) ethyl ether in hexane into a second K-D flask. Elute Fraction 3
with 200 mL of 50% (v/v) ethyl ether in hexane into a third K-D flask.
The elution patterns for the pesticides and PCBs are shown in Table 6.
11.3.5 Concentrate the fractions as in Section 10.3, except use
hexane to prewet the column and set the water bath at about 85 [deg]C.
When the apparatus is cool, remove the Snyder column and rinse the flask
and its lower joint into the concentrator tube with hexane. Adjust the
volume of Fraction 1 to approximately 10 mL for sulfur removal (Section
11.5), if required; otherwise, adjust the volume of the fractions to 10
mL, 1.0 mL, or other volume needed for the sensitivity desired. Analyze
the concentrated extract by gas chromatography (Section 12).
11.4 Alumina. The sample extract must be exchanged from methylene
chloride to hexane. Follow the solvent exchange steps in section
10.3.3.2 prior to attempting alumina cleanup.
11.4.1 If the chromatographic column does not contain a frit at the
bottom, place a small plug of pre-cleaned glass wool in the
chromatographic column (section 5.2.4) to retain the alumina. Add 10 g
of alumina (section 6.7.3) on top of the plug. Tap the column to settle
the alumina. Place 1-2 g of anhydrous sodium sulfate on top of the
alumina.
11.4.2 Close the stopcock and fill the column to just above the
sodium sulfate with hexane. Add 25 mL of hexane. Open the stopcock and
adjust the flow rate of hexane to approximately 2 mL/min. Do not allow
the column to go dry throughout the elutions.
11.4.3 When the level of the hexane is at the top of the column,
quantitatively transfer the extract to the column. When the level of the
extract is at the top of the column, slowly add 25 mL of hexane and
elute the column to the level of the sodium sulfate. Discard the hexane.
11.4.4 Place a K-D flask (section 5.2.5.1.2) under the column and
elute the pesticides
[[Page 176]]
with approximately 150 mL of hexane:ethyl ether (80:20 v/v). It may be
necessary to adjust the volume of elution solvent for slightly different
alumina activities.
11.4.5 Concentrate the extract per section 10.3.
11.5 Sulfur removal--Elemental sulfur will usually elute in Fraction
1 of the Florisil[supreg] column cleanup. If Florisil[supreg] cleanup is
not used, or to remove sulfur from any of the Florisil[supreg]
fractions, use one of the sulfur removal procedures below. These
procedures may be applied to extracts in hexane, ethyl ether, or
methylene chloride.
Note: Separate procedures using copper or TBA sulfite are provided
in this section for sulfur removal. They may be used separately or in
combination, if desired.
11.5.1 Removal with copper (Reference 15).
Note: Some of the analytes in Table 2 are not amenable to sulfur
removal with copper (e.g., atrazine and diazinon). Therefore, before
using copper to remove sulfur from an extract that will be analyzed for
any of the non-PCB analytes in Table 2, the laboratory must demonstrate
that the analytes can be extracted from an aqueous sample matrix that
contains sulfur and recovered from an extract treated with copper.
Acceptable performance can be demonstrated through the preparation and
analysis of a matrix spike sample that meets the QC requirements for
recovery.
11.5.1.1 Quantitatively transfer the extract to a 40- to 50-mL flask
or bottle. If there is evidence of water in the K-D or round-bottom
flask after the transfer, rinse the flask with small portions of
hexane:acetone (40:60) and add to the flask or bottle. Mark and set
aside the concentration flask for future use.
11.5.1.2 Add 10-20 g of granular anhydrous sodium sulfate to the
flask. Swirl to dry the extract.
11.5.1.3 Add activated copper (section 6.7.4.1.4) and allow to stand
for 30-60 minutes, swirling occasionally. If the copper does not remain
bright, add more and swirl occasionally for another 30-60 minutes.
11.5.1.4 After drying and sulfur removal, quantitatively transfer
the extract to a nitrogen-evaporation vial or tube and proceed to
section 10.3.3 for nitrogen evaporation and solvent exchange, taking
care to leave the sodium sulfate and copper foil in the flask.
11.5.2 Removal with TBA sulfite.
11.5.2.1 Using small volumes of hexane, quantitatively transfer the
extract to a 40- to 50-mL centrifuge tube with fluoropolymer-lined screw
cap.
11.5.2.2 Add 1-2 mL of TBA sulfite reagent (section 6.7.4.2.4), 2-3
mL of 2-propanol, and approximately 0.7 g of sodium sulfite (section
6.7.4.2.2) crystals to the tube. Cap and shake for 1-2 minutes. If the
sample is colorless or if the initial color is unchanged, and if clear
crystals (precipitated sodium sulfite) are observed, sufficient sodium
sulfite is present. If the precipitated sodium sulfite disappears, add
more crystalline sodium sulfite in approximately 0.5-g portions until a
solid residue remains after repeated shaking.
11.5.2.3 Add 5-10 mL of reagent water and shake for 1-2 minutes.
Centrifuge to settle the solids.
11.5.2.4 Quantitatively transfer the hexane (top) layer through a
small funnel containing a few grams of granular anhydrous sodium sulfate
to a nitrogen-evaporation vial or tube and proceed to section 10.3.3 for
micro-concentration and solvent exchange.
11.6 Acid back extraction (section 6.1.2).
11.6.1 Quantitatively transfer the extract (section 10.3.1.5) to a
250-mL separatory funnel.
11.6.2 Partition the extract against 50 mL of sulfuric acid solution
(section 6.1.2). Discard the aqueous layer. Repeat the acid washing
until no color is visible in the aqueous layer, to a maximum of four
washings.
11.6.3 Partition the extract against 50 mL of sodium chloride
solution (section 6.7.5). Discard the aqueous layer.
11.6.4 Proceed to section 10.3.3 for micro-concentration and solvent
exchange.
12. Gas Chromatography
12.1 Establish the same operating conditions used in section 7.1 for
instrument calibration.
12.2 If the internal standard calibration procedure is used, add the
internal standard solution (section 6.9.3) to the extract as close as
possible to the time of injection to minimize the possibility of loss by
evaporation, adsorption, or reaction. For example, add 1 [micro]L of 10
[micro]g/mL internal standard solution into the extract, assuming no
dilutions. Mix thoroughly.
12.3 Simultaneously inject an appropriate volume of the sample
extract or standard solution onto both columns, using split, splitless,
solvent purge, large-volume, or on-column injection. Alternatively, if
using a single-column GC configuration, inject an appropriate volume of
the sample extract or standard solution onto each GC column
independently. If the sample is injected manually, the solvent-flush
technique should be used. The injection volume depends upon the
technique used and the sensitivity needed to meet MDLs or reporting
limits for regulatory compliance. Injection volumes must be the same for
all extracts. Record the volume injected to the nearest 0.05 [micro]L.
12.4 Set the data system or GC control to start the temperature
program upon sample injection, and begin data collection after the
solvent peak elutes. Set the data system to stop data collection after
the last analyte is expected to elute and to return the column to the
initial temperature.
[[Page 177]]
12.5 Perform all qualitative and quantitative measurements as
described in Sections 14 and 15. When standards and extracts are not
being used for analyses, store them refrigerated at <6 [deg]C, protected
from light, in screw-cap vials equipped with un-pierced fluoropolymer-
lined septa.
13. System and Laboratory Performance
13.1 At the beginning of each shift during which standards or
extracts are analyzed, GC system performance and calibration must be
verified for all analytes and surrogates on both column/detector
systems. Adjustment and/or recalibration (per section 7) are performed
until all performance criteria are met. Only after all performance
criteria are met may samples, blanks and other QC samples, and standards
be analyzed.
13.2 Inject an aliquot of the calibration verification standard
(section 6.8.4) on both columns. Inject an aliquot of each of the multi-
component standards.
13.3 Retention times--The absolute retention times of the peak
maxima shall be within 2 seconds of the retention
times in the calibration verification (section 7.8).
13.4 GC resolution--Resolution is acceptable if the valley height
between two peaks (as measured from the baseline) is less than 40% of
the shorter of the two peaks.
13.4.1 DB-608 column--DDT and endrin aldehyde
13.4.2 DB-1701 column--alpha and gamma chlordane
Note: If using other GC columns or stationary phases, these
resolution criteria apply to these four target analytes and any other
closely eluting analytes on those other GC columns.
13.5 Decomposition of DDT and endrin--If DDT, endrin, or their
breakdown products are to be determined, this test must be performed
prior to calibration verification (section 13.6). DDT decomposes to DDE
and DDD. Endrin decomposes to endrin aldehyde and endrin ketone.
13.5.1 Inject 1 [micro]L of the DDT and endrin decomposition
solution (section 6.8.7). As noted in section 6.8.7, other injection
volumes may be used as long as the concentrations of DDT and endrin in
the solution are adjusted to introduce the masses of the two analytes
into the instrument that are listed in section 6.8.7.
13.5.2 Measure the areas of the peaks for DDT, DDE, DDD, endrin,
endrin aldehyde, and endrin ketone in the chromatogram and calculate the
percent breakdown as shown in the equations below:
[GRAPHIC] [TIFF OMITTED] TR28AU17.005
13.5.3 Both the % breakdown of DDT and of endrin must be less than
20%, otherwise the system is not performing acceptably for DDT and
endrin. In this case, repair the GC column system that failed and repeat
the performance tests (sections 13.2 to 13.6) until the specification is
met.
Note: DDT and endrin decomposition are usually caused by
accumulations of particulates in the injector and in the front end of
the column. Cleaning and silanizing the injection port liner, and
breaking off a short section of the front end of the column will usually
eliminate the decomposition problem. Either of these corrective actions
may affect retention times, GC resolution, and calibration linearity.
13.6 Calibration verification.
13.6.1 Compute the percent recovery of each analyte and of the
coeluting analytes, based on the initial calibration data (section 7.5
or 7.6).
13.6.2 For each analyte or for coeluting analytes, compare the
concentration with the limits for calibration verification in Table 4.
For coeluting analytes, use the coeluting analyte with the least
restrictive specification (the widest range). For analytes in Table 2
not listed in Table 4, QC acceptance criteria must be developed by the
laboratory. EPA has provided guidance for development of QC acceptance
criteria (References 13 and 14). If the recoveries for all analytes meet
the acceptance criteria, system performance is acceptable and analysis
of blanks and samples may continue. If, however, any recovery falls
outside the calibration verification range, system performance is
unacceptable for that analyte. If this occurs, repair the system and
repeat the test (section 13.6), or prepare a fresh calibration
[[Page 178]]
standard and repeat the test, or recalibrate (section 7). See Section
8.1.7 for information on repeated test failures.
13.7 Laboratory control sample.
13.7.1 Analyze the extract of the LCS (section 6.8.3) extracted with
each sample batch (Section 8.4). See Section 8.4 for criteria acceptance
of the LCS.
13.7.2 It is suggested, but not required, that the laboratory update
statements of data quality. Add results that pass the specifications in
section 13.7.3 to initial (section 8.7) and previous ongoing data.
Update QC charts to form a graphic representation of continued
laboratory performance. Develop a statement of laboratory data quality
for each analyte by calculating the average percent recovery (R) and the
standard deviation of percent recovery, sr. Express the accuracy as a
recovery interval from R - 2sr to R + 2sr. For example, if R = 95% and
sr = 5%, the accuracy is 85 to 105%.
13.8 Internal standard response--If internal standard calibration is
used, verify that detector sensitivity has not changed by comparing the
response (area or height) of each internal standard in the sample,
blank, LCS, MS, and MSD to the response in calibration verification
(section 6.8.3). The peak area or height of the internal standard should
be within 50% to 200% (\1/2\ to 2x) of its respective peak area or
height in the verification standard. If the area or height is not within
this range, compute the concentration of the analytes using the external
standard method (section 7.5). If the analytes are affected, re-prepare
and reanalyze the sample, blank, LCS, MS, or MSD, and repeat the
pertinent test.
14. Qualitative Identification
14.1 Identification is accomplished by comparison of data from
analysis of a sample, blank, or other QC sample with data from
calibration verification (section 7.7.1 or 13.5), and with data stored
in the retention-time and calibration libraries (section 7.7). The
retention time window is determined as described in section 14.2.
Identification is confirmed when retention time agrees on both GC
columns, as described below. Alternatively, GC/MS identification may be
used to provide another means of identification.
14.2 Establishing retention time windows.
14.2.1 Using the data from the multi-point initial calibration
(section 7.4), determine the retention time in decimal minutes (not
minutes:seconds) of each peak representing a single-component target
analyte on each column/detector system. For the multi-component
analytes, use the retention times of the five largest peaks in the
chromatograms on each column/detector system.
14.2.2 Calculate the standard deviation of the retention times for
each single-component analyte on each column/detector system and for the
three to five exclusive (unique large) peaks for each multi-component
analyte.
14.2.3 Define the width of the retention time window as three times
that standard deviation. Establish the center of the retention time
window for each analyte by using the absolute retention time for each
analyte from the calibration verification standard at the beginning of
the analytical shift. For samples run during the same shift as an
initial calibration, use the retention time of the mid-point standard of
the initial calibration. If the calculated RT window is less than 0.02
minutes, then use 0.02 minutes as the window.
Note: Procedures for establishing retention time windows from other
sources may be employed provided that they are clearly documented and
provide acceptable performance. Such performance may be evaluated using
the results for the spiked QC samples described in this method, such as
laboratory control samples and matrix spike samples.
14.2.4 The retention time windows must be recentered when a new GC
column is installed or if a GC column has been shortened during
maintenance to a degree that the retention times of analytes in the
calibration verification standard have shifted close to the lower limits
of the established retention time windows.
14.2.5 RT windows should be checked periodically by examining the
peaks in spiked samples such as the LCS or MS/MSD to confirm that peaks
for known analytes are properly identified.
14.2.6 If the retention time of an analyte in the calibration
(Section 7.4) varies by more than 5 seconds across the calibration range
as a function of the concentration of the standard, using the standard
deviation of the retention times (section 14.2.3) to set the width of
the retention time window may not adequately serve to identify the
analyte in question under routine conditions. In such cases, data from
additional analyses of standards may be required to adequately model the
chromatographic behavior of the analyte.
14.3 Identifying the analyte in a sample.
14.3.1 In order to identify a single-component analyte from analysis
of a sample, blank, or other QC sample, the peak representing the
analyte must fall within its respective retention time windows on both
column/detector systems (as defined in section 14.2). That
identification is further supported by the comparison of the numerical
results on both columns, as described in section 15.7.
14.3.2 In order to identify a multi-component analyte, pattern
matching (fingerprinting) may be used, or the three to five exclusive
(unique and largest) peaks for that analyte must fall within their
respective retention time windows on both column/detector systems (as
defined in section 14.2).
[[Page 179]]
That identification is further supported by the comparison of the
numerical results on both columns, as described in section 15.7.
Alternatively, GC/MS identification may be used. Differentiation among
some of the Aroclors may require evaluation of more than five peaks to
ensure correct identification.
14.4 GC/MS confirmation. When the concentration of an analyte is
sufficient and the presence or identity is suspect, its presence should
be confirmed by GC/MS. In order to match the sensitivity of the GC/ECD,
confirmation would need to be by GC/MS-SIM, or the estimated
concentration would need to be 100 times higher than the GC/ECD
calibration range. The extract may be concentrated by an additional
amount to allow a further attempt at GC/MS confirmation.
14.5 Additional information that may aid the laboratory in the
identification of an analyte. The occurrence of peaks eluting near the
retention time of an analyte of interest increases the probability of a
false positive for the analyte. If the concentration is insufficient for
confirmation by GC/MS, the laboratory may use the cleanup procedures in
this method (section 11) on a new sample aliquot to attempt to remove
the interferent. After attempts at cleanup are exhausted, the following
steps may be helpful to assure that the substance that appears in the RT
windows on both columns is the analyte of interest.
14.5.1 Determine the consistency of the RT data for the analyte on
each column. For example, if the RT is very stable (i.e., varies by no
more than a few seconds) for the calibration, calibration verification,
blank, LCS, and MS/MSD, the RT for the analyte of interest in the sample
should be within this variation regardless of the window established in
Section 14.2. If the analyte is not within this variation on both
columns, it is likely not present.
14.5.2 The possibility exists that the RT for the analyte in a
sample could shift if extraneous materials are present. This possibility
may be able to be confirmed or refuted by the behavior of the surrogates
in the sample. If multiple surrogates are used that span the length of
the chromatographic run, the RTs for the surrogates on both columns are
consistent with their RTs in calibration, calibration verification,
blank, LCS, and MS/MSD, it is unlikely that the RT for the analyte of
interest has shifted.
14.5.3 If the RT for the analyte is shifted slightly later on one
column and earlier on the other, and the surrogates have not shifted, it
is highly unlikely that the analyte is present, because shifts nearly
always occur in the same direction on both columns.
15. Quantitative Determination
15.1 External standard quantitation--Calculate the concentration of
the analyte in the extract using the calibration curve or average
calibration factor determined in calibration (section 7.5.2) and the
following equation:
[GRAPHIC] [TIFF OMITTED] TR28AU17.006
where:
Cex = Concentration of the analyte in the extract (ng/mL)
As = Peak height or area for the analyte in the standard or
sample
CF = Calibration factor, as defined in Section 7.5.1
15.2 Internal standard quantitation--Calculate the concentration of
the analyte in the extract using the calibration curve or average
response factor determined in calibration (section 7.6.2) and the
following equation:
[GRAPHIC] [TIFF OMITTED] TR28AU17.007
where:
Cex = Concentration of the analyte in the extract (ng/mL)
As = Peak height or area for the analyte in the standard or
sample
Cis = Concentration of the internal standard (ng/mL)
Ais = Area of the internal standard
RF = Response factor, as defined in section 7.6.1
[[Page 180]]
15.3 Calculate the concentration of the analyte in the sample using
the concentration in the extract, the extract volume, the sample volume,
and the dilution factor, per the following equation:
[GRAPHIC] [TIFF OMITTED] TR28AU17.008
where:
Cs = Concentration of the analyte in the sample ([micro]g/L)
Vex = Final extract volume (mL)
Cex = Concentration in the extract (ng/mL)
Vs = Volume of sample (L)
DF = Dilution factor
and the factor of 1,000 in the denominator converts the final units from
ng/L to [micro]g/L
15.4 If the concentration of any target analyte exceeds the
calibration range, either extract and analyze a smaller sample volume,
or dilute and analyze the diluted extract.
15.5 Quantitation of multi-component analytes.
15.5.1 PCBs as Aroclors. Quantify an Aroclor by comparing the sample
chromatogram to that of the most similar Aroclor standard as indicated
in section 14.3.2. Compare the responses of 3 to 5 major peaks in the
calibration standard for that Aroclor with the peaks observed in the
sample extract. The amount of Aroclor is calculated using the individual
calibration factor for each of the 3 to 5 characteristic peaks chosen in
section 7.5.1. Determine the concentration of each of the characteristic
peaks, using the average calibration factor calculated for that peak in
section 7.5.2, and then those 3 to 5 concentrations are averaged to
determine the concentration of that Aroclor.
15.5.2 Other multi-component analytes. Quantify any other multi-
component analytes (technical chlordane or toxaphene) using the same
peaks used to develop the average calibration factors in section 7.5.2.
Determine the concentration of each of the characteristic peaks, and
then the concentrations represented by those characteristic peaks are
averaged to determine the concentration of the analyte. Alternatively,
for toxaphene, the analyst may determine the calibration factor in
section 7.5.2 by summing the areas of all of the peaks for the analyte
and using the summed of the peak areas in the sample chromatogram to
determine the concentration. However, the approach used for toxaphene
must be the same for the calibration and the sample analyses.
15.6 Reporting of results. As noted in section 1.6.1, EPA has
promulgated this method at 40 CFR part 136 for use in wastewater
compliance monitoring under the National Pollutant Discharge Elimination
System (NPDES). The data reporting practices described here are focused
on such monitoring needs and may not be relevant to other uses of the
method.
15.6.1 Report results for wastewater samples in [micro]g/L without
correction for recovery. (Other units may be used if required by in a
permit.) Report all QC data with the sample results.
15.6.2 Reporting level. Unless specified otherwise by a regulatory
authority or in a discharge permit, results for analytes that meet the
identification criteria are reported down to the concentration of the ML
established by the laboratory through calibration of the instrument (see
section 7.5 or 7.6 and the glossary for the derivation of the ML). EPA
considers the terms ``reporting limit,'' ``quantitation limit,'' and
``minimum level'' to be synonymous.
15.6.2.1 Report the lower result from the two columns (see section
15.7 below) for each analyte in each sample or QC standard at or above
the ML to 3 significant figures. Report a result for each analyte in
each sample or QC standard below the ML as ``12, are hazardous and must
be handled and disposed of as hazardous waste, or neutralized and
disposed of in accordance with all federal, state, and local
regulations. It is the laboratory's responsibility to comply with all
federal, state, and local regulations governing waste management,
particularly the hazardous waste identification rules and land disposal
restrictions. The laboratory using this method has the responsibility to
protect the air, water, and land by minimizing and controlling all
releases from fume hoods and bench operations. Compliance is also
required with any sewage discharge permits and regulations. For further
information on waste management, see ``The Waste Management Manual for
Laboratory Personnel,'' also available from the American Chemical
Society at the address in section 18.3.
19.3 Many analytes in this method decompose above 500 [deg]C. Low-
level waste such as absorbent paper, tissues, animal remains, and
plastic gloves may be burned in an appropriate incinerator. Gross
quantities of neat or highly concentrated solutions of toxic or
hazardous chemicals should be packaged securely and disposed of through
commercial or governmental channels that are capable of handling toxic
wastes.
19.4 For further information on waste management, consult The Waste
Management Manual for Laboratory Personnel and
[[Page 183]]
Less is Better-Laboratory Chemical Management for Waste Reduction,
available from the American Chemical Society's Department of Government
Relations and Science Policy, 1155 16th Street NW., Washington, DC
20036, 202-872-4477.
20. References
1. ``Determination of Pesticides and PCBs in Industrial and Municipal
Wastewaters,'' EPA 600/4-82-023, National Technical
Information Service, PB82-214222, Springfield, Virginia 22161,
April 1982.
2. ``EPA Method Study 18 Method 608-Organochlorine Pesticides and
PCBs,'' EPA 600/4-84-061, National Technical Information
Service, PB84-211358, Springfield, Virginia 22161, June 1984.
3. ``Method Detection Limit and Analytical Curve Studies, EPA Methods
606, 607, and 608,'' Special letter report for EPA Contract
68-03-2606, U.S. Environmental Protection Agency,
Environmental Monitoring and Support Laboratory, Cincinnati,
Ohio 45268, June 1980.
4. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard Practice
for Preparation of Sample Containers and for Preservation of
Organic Constituents,'' American Society for Testing and
Materials, Philadelphia.
5. Giam, C.S., Chan, H.S., and Nef, G.S. ``Sensitive Method for
Determination of Phthalate Ester Plasticizers in Open-Ocean
Biota Samples,'' Analytical Chemistry, 47:2225 (1975).
6. Giam, C.S. and Chan, H.S. ``Control of Blanks in the Analysis of
Phthalates in Air and Ocean Biota Samples,'' U.S. National
Bureau of Standards, Special Publication 442, pp. 701-708,
1976.
7. Solutions to Analytical Chemistry Problems with Clean Water Act
Methods, EPA 821-R-07-002, March 2007.
8. ``Carcinogens-Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for
Disease Control, National Institute for Occupational Safety
and Health, Publication No. 77-206, August 1977.
9. ``Occupational Exposure to Hazardous Chemicals in Laboratories,'' (29
CFR 1910.1450), Occupational Safety and Health Administration,
OSHA.
10. 40 CFR 136.6(b)(4)(j).
11. Mills, P.A. ``Variation of Florisil Activity: Simple Method for
Measuring Absorbent Capacity and Its Use in Standardizing
Florisil Columns,'' Journal of the Association of Official
Analytical Chemists, 51:29, (1968).
12. 40 CFR 136.6(b)(2)(i).
13. Protocol for EPA Approval of New Methods for Organic and Inorganic
Analytes in Wastewater and Drinking Water (EPA-821-B-98-003)
March 1999.
14. Methods 4500 Cl F and 4500 Cl G, Standard Methods for the
Examination of Water and Wastewater, published jointly by the
American Public Health Association, American Water Works
Association, and Water Environment Federation, 1015 Fifteenth
St., Washington, DC 20005, 20th Edition, 2000.
15. ``Manual of Analytical Methods for the Analysis of Pesticides in
Human and Environmental Samples,'' EPA-600/8-80-038, U.S.
Environmental Protection Agency, Health Effects Research
Laboratory, Research Triangle Park, North Carolina.
16. USEPA, 2000, Method 1656 Organo-Halide Pesticides In Wastewater,
Soil, Sludge, Sediment, and Tissue by GC/HSD, EPA-821-R-00-
017, September 2000.
17. USEPA, 2010, Method 1668C Chlorinated Biphenyl Congeners in Water,
Soil, Sediment, Biosolids, and Tissue by HRGC/HRMS, EPA-820-R-
10-005, April 2010.
18. USEPA, 2007, Method 1699: Pesticides in Water, Soil, Sediment,
Biosolids, and Tissue by HRGC/HRMS, EPA-821-R-08-001, December
2007.
19. ``Less is Better,'' American Chemical Society on-line publication,
http://www.acs.org/content/dam/acsorg/about/governance/
committees/chemicalsafety/publications/less-is-better.pdf.
20. EPA Method 608 ATP 3M0222, An alternative test procedure for the
measurement of organochlorine pesticides and polychlorinated
biphenyls in waste water. Federal Register, Vol. 60, No. 148
August 2, 1995.
21. Tables
Table 1--Pesticides \1\
----------------------------------------------------------------------------------------------------------------
Analyte CAS No. MDL \2\ (ng/L) ML \3\ (ng/L)
----------------------------------------------------------------------------------------------------------------
Aldrin.......................................................... 309-00-2 4 12
alpha-BHC....................................................... 319-84-6 3 9
beta-BHC........................................................ 319-85-7 6 18
delta-BHC....................................................... 319-86-8 9 27
gamma-BHC (Lindane)............................................. 58-89-9 4 12
alpha-Chlordane \ 4\............................................ 5103-71-9 14 42
gamma-Chlordane \ 4\............................................ 5103-74-2 14 42
4,4[min]-DDD.................................................... 72-54-8 11 33
4,4[min]-DDE.................................................... 72-55-9 4 12
4,4[min]-DDT.................................................... 50-29-3 12 36
[[Page 184]]
Dieldrin........................................................ 60-57-1 2 6
Endosulfan I.................................................... 959-98-8 14 42
Endosulfan II................................................... 33213-65-9 4 12
Endosulfan sulfate.............................................. 1031-07-8 66 198
Endrin.......................................................... 72-20-8 6 18
Endrin aldehyde................................................. 7421-93-4 23 70
Heptachlor...................................................... 76-44-8 3 9
Heptachlor epoxide.............................................. 1024-57-3 83 249
----------------------------------------------------------------------------------------------------------------
\1\ All analytes in this table are Priority Pollutants (40 CFR part 423, appendix A).
\2\ 40 CFR part 136, appendix B, June 30, 1986.
\3\ ML = Minimum Level--see Glossary for definition and derivation, calculated as 3 times the MDL.
\4\ MDL based on the MDL for Chlordane.
Table 2--Additional Analytes
----------------------------------------------------------------------------------------------------------------
Analyte CAS No. MDL \3\ (ng/L) ML \4\ (ng/L)
----------------------------------------------------------------------------------------------------------------
Acephate........................................................ 30560-19-1
Alachlor........................................................ 15972-60-8
Atrazine........................................................ 1912-24-9
Benfluralin (Benefin)........................................... 1861-40-1
Bromacil........................................................ 314-40-9
Bromoxynil octanoate............................................ 1689-99-2
Butachlor....................................................... 23184-66-9
Captafol........................................................ 2425-06-1
Captan.......................................................... 133-06-2
Carbophenothion (Trithion)...................................... 786-19-6
Chlorobenzilate................................................. 510-15-6
Chloroneb (Terraneb)............................................ 2675-77-6
Chloropropylate (Acaralate)..................................... 5836-10-2
Chlorothalonil.................................................. 1897-45-6
Cyanazine....................................................... 21725-46-2
DCPA (Dacthal).................................................. 1861-32-1
2,4[min]-DDD.................................................... 53-19-0
2,4[min]-DDE.................................................... 3424-82-6
2,4[min]-DDT.................................................... 789-02-6
Diallate (Avadex)............................................... 2303-16-4
1,2-Dibromo-3-chloropropane (DBCP).............................. 96-12-8
Dichlone........................................................ 117-80-6
Dichloran....................................................... 99-30-9
Dicofol......................................................... 115-32-2
Endrin ketone................................................... 53494-70-5
Ethalfluralin (Sonalan)......................................... 55283-68-6
Etridiazole..................................................... 2593-15-9
Fenarimol (Rubigan)............................................. 60168-88-9
Hexachlorobenzene \1\........................................... 118-74-1
Hexachlorocyclopentadiene \1\................................... 77-47-4
Isodrin......................................................... 465-73-6
Isopropalin (Paarlan)........................................... 33820-53-0
Kepone.......................................................... 143-50-0
Methoxychlor.................................................... 72-43-5
Metolachlor..................................................... 51218-45-2
Metribuzin...................................................... 21087-64-9
Mirex........................................................... 2385-85-5
Nitrofen (TOK).................................................. 1836-75-5
cis-Nonachlor................................................... 5103-73-1
trans-Nonachlor................................................. 39765-80-5
Norfluorazon.................................................... 27314-13-2
Octachlorostyrene............................................... 29082-74-4
Oxychlordane.................................................... 27304-13-8
PCNB (Pentachloronitrobenzene).................................. 82-68-8
Pendamethalin (Prowl)........................................... 40487-42-1
cis-Permethrin.................................................. 61949-76-6
trans-Permethrin................................................ 61949-77-7
Perthane (Ethylan).............................................. 72-56-0
Propachlor...................................................... 1918-16-7
Propanil........................................................ 709-98-8
Propazine....................................................... 139-40-2
Quintozene...................................................... 82-68-8
Simazine........................................................ 122-34-9
[[Page 185]]
Strobane........................................................ 8001-50-1
Technazene...................................................... 117-18-0
Technical Chlordane \2\......................................... ..............
Terbacil........................................................ 5902-51-2
Terbuthylazine.................................................. 5915-41-3
Toxaphene \1\................................................... 8001-35-2 240 720
Trifluralin..................................................... 1582-09-8
PCB-1016 \1\.................................................... 12674-11-2
PCB-1221 \1\.................................................... 11104-28-2
PCB-1232 \1\.................................................... 11141-16-5
PCB-1242 \1\.................................................... 53469-21-9 65 95
PCB-1248 \1\.................................................... 12672-29-6
PCB-1254 \1\.................................................... 11097-69-1
PCB-1260 \1\.................................................... 11096-82-5
PCB-1268........................................................ 11100-14-4 ..............
----------------------------------------------------------------------------------------------------------------
\1\ Priority Pollutants (40 CFR part 423, appendix A).
\2\ Technical Chlordane may be used in cases where historical reporting has only been for this form of
Chlordane.
\3\ 40 CFR part 136, appendix B, June 30, 1986.
\4\ ML = Minimum Level--see Glossary for definition and derivation, calculated as 3 times the MDL.
Table 3--Example Retention Times \1\
------------------------------------------------------------------------
Retention time (min) \2\
Analyte -------------------------------
DB-608 DB-1701
------------------------------------------------------------------------
Acephate................................ 5.03 (\3\)
Trifluralin............................. 5.16 6.79
Ethalfluralin........................... 5.28 6.49
Benfluralin............................. 5.53 6.87
Diallate-A.............................. 7.15 6.23
Diallate-B.............................. 7.42 6.77
alpha-BHC............................... 8.14 7.44
PCNB.................................... 9.03 7.58
Simazine................................ 9.06 9.29
Atrazine................................ 9.12 9.12
Terbuthylazine.......................... 9.17 9.46
gamma-BHC (Lindane)..................... 9.52 9.91
beta-BHC................................ 9.86 11.90
Heptachlor.............................. 10.66 10.55
Chlorothalonil.......................... 10.66 10.96
Dichlone................................ 10.80 (\4\)
Terbacil................................ 11.11 12.63
delta-BHC............................... 11.20 12.98
Alachlor................................ 11.57 11.06
Propanil................................ 11.60 14.10
Aldrin.................................. 11.84 11.46
DCPA.................................... 12.18 12.09
Metribuzin.............................. 12.80 11.68
Triadimefon............................. 12.99 13.57
Isopropalin............................. 13.06 13.37
Isodrin................................. 13.47 11.12
Heptachlor epoxide...................... 13.97 12.56
Pendamethalin........................... 14.21 13.46
Bromacil................................ 14.39 (\3\)
alpha-Chlordane......................... 14.63 14.20
Butachlor............................... 15.03 15.69
gamma-Chlordane......................... 15.24 14.36
Endosulfan I............................ 15.25 13.87
4,4[min]-DDE............................ 16.34 14.84
Dieldrin................................ 16.41 15.25
Captan.................................. 16.83 15.43
Chlorobenzilate......................... 17.58 17.28
Endrin.................................. 17.80 15.86
Nitrofen (TOK).......................... 17.86 17.47
Kepone.................................. 17.92 (3 5)
4,4[min]-DDD............................ 18.43 17.77
Endosulfan II........................... 18.45 18.57
Bromoxynil octanoate.................... 18.85 18.57
4,4[min]-DDT............................ 19.48 18.32
[[Page 186]]
Carbophenothion......................... 19.65 18.21
Endrin aldehyde......................... 19.72 19.18
Endosulfan sulfate...................... 20.21 20.37
Captafol................................ 22.51 21.22
Norfluorazon............................ 20.68 22.01
Mirex................................... 22.75 19.79
Methoxychlor............................ 22.80 20.68
Endrin ketone........................... 23.00 21.79
Fenarimol............................... 24.53 23.79
cis-Permethrin.......................... 25.00 23.59
trans-Permethrin........................ 25.62 23.92
PCB-1016................................
PCB-1221................................
PCB-1232................................
PCB-1242................................
PCB-1248................................
PCB-1254................................
PCB-1260 (5 peaks)...................... 15.44 14.64
15.73 15.36
16.94 16.53
17.28 18.70
19.17 19.92
Toxaphene (5 peaks)..................... 16.60 16.60
17.37 17.52
18.11 17.92
19.46 18.73
19.69 19.00
------------------------------------------------------------------------
\1\ Data from EPA Method 1656 (Reference 16).
\2\ Columns: 30-m long x 0.53-mm ID fused-silica capillary; DB-608, 0.83
[micro]m; and DB-1701, 1.0 [micro]m.
Conditions suggested to meet retention times shown: 150 [deg]C for 0.5
minute, 150-270 [deg]C at 5 [deg]C/min, and 270 [deg]C until trans-
Permethrin elutes.
Carrier gas flow rates approximately 7 mL/min.
\3\ Does not elute from DB-1701 column at level tested.
\4\ Not recovered from water at the levels tested.
\5\ Dichlone and Kepone do not elute from the DB-1701 column and should
be confirmed on DB-5.
Table 4--QC Acceptance Criteria
--------------------------------------------------------------------------------------------------------------------------------------------------------
Calibration Test
Analyte verification concentration Limit for s (% Range for X Range for P Maximum MS/MSD
(%) ([micro]g/L) SD) (%) (%) RPD (%)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Aldrin.................................................. 75-125 2.0 25 54-130 42-140 35
alpha-BHC............................................... 69-125 2.0 28 49-130 37-140 36
beta-BHC................................................ 75-125 2.0 38 39-130 17-147 44
delta-BHC............................................... 75-125 2.0 43 51-130 19-140 52
gamma-BHC............................................... 75-125 2.0 29 43-130 32-140 39
alpha-Chlordane......................................... 73-125 50.0 24 55-130 45-140 35
gamma-Chlordane......................................... 75-125 50.0 24 55-130 45-140 35
4,4[min]-DDD............................................ 75-125 10.0 32 48-130 31-141 39
4,4[min]-DDE............................................ 75-125 2.0 30 54-130 30-145 35
4,4[min]-DDT............................................ 75-125 10.0 39 46-137 25-160 42
Dieldrin................................................ 48-125 2.0 42 58-130 36-146 49
Endosulfan I............................................ 75-125 2.0 25 57-141 45-153 28
Endosulfan II........................................... 75-125 10.0 63 22-171 D-202 53
Endosulfan sulfate...................................... 70-125 10.0 32 38-132 26-144 38
Endrin.................................................. 5-125 10.0 42 51-130 30-147 48
Heptachlor.............................................. 75-125 2.0 28 43-130 34-140 43
Heptachlor epoxide...................................... 75-125 2.0 22 57-132 37-142 26
Toxaphene............................................... 68-134 50.0 30 56-130 41-140 41
PCB-1016................................................ 75-125 50.0 24 61-103 50-140 36
PCB-1221................................................ 75-125 50.0 50 44-150 15-178 48
PCB-1232................................................ 75-125 50.0 32 28-197 10-215 25
PCB-1242................................................ 75-125 50.0 26 50-139 39-150 29
PCB-1248................................................ 75-125 50.0 32 58-140 38-158 35
PCB-1254................................................ 75-125 50.0 34 44-130 29-140 45
PCB-1260................................................ 75-125 50.0 28 37-130 8-140 38
--------------------------------------------------------------------------------------------------------------------------------------------------------
S = Standard deviation of four recovery measurements for the DOC (section 8.2.4).
X = Average of four recovery measurements for the DOC (section 8.2.4).
[[Page 187]]
P = Recovery for the LCS (section 8.4.3).
Note: These criteria were developed from data in Table 5 (Reference 2). Where necessary, limits for recovery have been broadened to assure applicability
to concentrations below those in Table 5.
Table 5--Precision and Recovery as Functions of Concentration
----------------------------------------------------------------------------------------------------------------
Single analyst
Recovery, X[min] precision, Overall
Analyte ([micro]g/L) sr[min] ([micro]g/ precision, S[min]
L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
Aldrin................................................. 0.81C + 0.04 0.16(X) - 0.04 0.20(X) - 0.01
alpha-BHC.............................................. 0.84C + 0.03 0.13(X) + 0.04 0.23(X) - 0.00
beta-BHC............................................... 0.81C + 0.07 0.22(X) - 0.02 0.33(X) - 0.05
delta-BHC.............................................. 0.81C + 0.07 0.18(X) + 0.09 0.25(X) + 0.03
gamma-BHC (Lindane).................................... 0.82C - 0.05 0.12(X) + 0.06 0.22(X) + 0.04
Chlordane.............................................. 0.82C - 0.04 0.13(X) + 0.13 0.18(X) + 0.18
4,4[min]-DDD........................................... 0.84C + 0.30 0.20(X) - 0.18 0.27(X) - 0.14
4,4[min]-DDE........................................... 0.85C + 0.14 0.13(X) + 0.06 0.28(X) - 0.09
4,4[min]-DDT........................................... 0.93C - 0.13 0.17(X) + 0.39 0.31(X) - 0.21
Dieldrin............................................... 0.90C + 0.02 0.12(X) + 0.19 0.16(X) + 0.16
Endosulfan I........................................... 0.97C + 0.04 0.10(X) + 0.07 0.18(X) + 0.08
Endosulfan II.......................................... 0.93C + 0.34 0.41(X) - 0.65 0.47(X) - 0.20
Endosulfan sulfate..................................... 0.89C - 0.37 0.13(X) + 0.33 0.24(X) + 0.35
Endrin................................................. 0.89C - 0.04 0.20(X) + 0.25 0.24(X) + 0.25
Heptachlor............................................. 0.69C + 0.04 0.06(X) + 0.13 0.16(X) + 0.08
Heptachlor epoxide..................................... 0.89C + 0.10 0.18(X) - 0.11 0.25(X) - 0.08
Toxaphene.............................................. 0.80C + 1.74 0.09(X) + 3.20 0.20(X) + 0.22
PCB-1016............................................... 0.81C + 0.50 0.13(X) + 0.15 0.15(X) + 0.45
PCB-1221............................................... 0.96C + 0.65 0.29(X) - 0.76 0.35(X) - 0.62
PCB-1232............................................... 0.91C + 10.8 0.21(X) - 1.93 0.31(X) + 3.50
PCB-1242............................................... 0.93C + 0.70 0.11(X) + 1.40 0.21(X) + 1.52
PCB-1248............................................... 0.97C + 1.06 0.17(X) + 0.41 0.25(X) - 0.37
PCB-1254............................................... 0.76C + 2.07 0.15(X) + 1.66 0.17(X) + 3.62
PCB-1260............................................... 0.66C + 3.76 0.22(X) - 2.37 0.39(X) - 4.86
----------------------------------------------------------------------------------------------------------------
X[min] = Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/
L.
Table 6--Distribution of Chlorinated Pesticides and PCBs Into Florisil[supreg] Column Fractions
----------------------------------------------------------------------------------------------------------------
Percent Recovery by Fraction \1\
Analyte -----------------------------------------------
1 2 3
----------------------------------------------------------------------------------------------------------------
Aldrin.......................................................... 100
alpha-BHC....................................................... 100
beta-BHC........................................................ 97
delta-BHC....................................................... 98
gamma-BHC (Lindane)............................................. 100
Chlordane....................................................... 100
4,4[min]-DDD.................................................... 99
4,4[min]-DDE.................................................... .............. 98
4,4[min]-DDT.................................................... 100
Dieldrin........................................................ 0 100
Endosulfan I.................................................... 37 64
Endosulfan II................................................... 0 7 91
Endosulfan sulfate.............................................. 0 0 106
Endrin.......................................................... 4 96
Endrin aldehyde................................................. 0 68 26
Heptachlor...................................................... 100
Heptachlor epoxide.............................................. 100
Toxaphene....................................................... 96
PCB-1016........................................................ 97
PCB-1221........................................................ 97
PCB-1232........................................................ 95 4
PCB-1242........................................................ 97
PCB-1248........................................................ 103
PCB-1254........................................................ 90
PCB-1260........................................................ .............. ..............
----------------------------------------------------------------------------------------------------------------
\1\ Eluant composition:
Fraction 1--6% ethyl ether in hexane.
Fraction 2--15% ethyl ether in hexane.
Fraction 3--50% ethyl ether in hexane.
[[Page 188]]
Table 7--Suggested Calibration Groups \1\
------------------------------------------------------------------------
Analyte
-------------------------------------------------------------------------
Calibration Group 1:
Acephate
Alachlor
Atrazine
beta-BHC
Bromoxynil octanoate
Captafol
Diallate
Endosulfan sulfate
Endrin
Isodrin
Pendimethalin (Prowl)
trans-Permethrin
Calibration Group 2:
alpha-BHC
DCPA
4,4[min]-DDE
4,4[min]-DDT
Dichlone
Ethalfluralin
Fenarimol
Methoxychlor
Metribuzin
Calibration Group 3:
gamma-BHC (Lindane)
gamma-Chlordane
Endrin ketone
Heptachlor epoxide
Isopropalin
Nitrofen (TOK)
PCNB
cis-Permethrin
Trifluralin
Callibration Group 4:
Benfluralin
Chlorobenzilate
Dieldrin
Endosulfan I
Mirex
Terbacil
Terbuthylazine
Triadimefon
Calibration Group 5:
alpha-Chlordane
Captan
Chlorothalonil
4,4[min]-DDD
Norfluorazon
Simazine
Calibration Group 6:
Aldrin
delta-BHC
Bromacil
Butachlor
Endosulfan II
Heptachlor
Kepone
Calibration Group 7:
Carbophenothion
Chloroneb
Chloropropylate
DBCP
Dicofol
Endrin aldehyde
Etridiazone
Perthane
Propachlor
Propanil
Propazine
------------------------------------------------------------------------
\1\ The analytes may be organized in other calibration groups, provided
that there are no coelution problems and that all QC requirements are
met.
22. Figures
[[Page 189]]
[GRAPHIC] [TIFF OMITTED] TR28AU17.010
[[Page 190]]
[GRAPHIC] [TIFF OMITTED] TR28AU17.011
23. Glossary
These definitions and purposes are specific to this method but have
been conformed to common usage to the extent possible.
23.1 Units of weight and measure and their abbreviations.
23.1.1 Symbols.
[deg]C degrees Celsius
[micro]g microgram
[[Page 191]]
[micro]L microliter
< less than
<= less than or equal to
greater than
% percent
23.1.2 Abbreviations (in alphabetical order).
cm centimeter
g gram
hr hour
ID inside diameter
in. inch
L liter
M molar solution--one mole or gram molecular weight of solute in one
liter of solution
mg milligram
min minute
mL milliliter
mm millimeter
N Normality--one equivalent of solute in one liter of solution
ng nanogram
psia pounds-per-square inch absolute
psig pounds-per-square inch gauge
v/v volume per unit volume
w/v weight per unit volume
23.2 Definitions and acronyms (in alphabetical order)
Analyte--A compound or mixture of compounds (e.g., PCBs) tested for
by this method. The analytes are listed in Tables 1 and 2.
Analytical batch--The set of samples analyzed on a given instrument
during a 24-hour period that begins and ends with calibration
verification (sections 7.8 and 13). See also ``Extraction batch.''
Blank (method blank; laboratory blank)--An aliquot of reagent water
that is treated exactly as a sample including exposure to all glassware,
equipment, solvents, reagents, internal standards, and surrogates that
are used with samples. The blank is used to determine if analytes or
interferences are present in the laboratory environment, the reagents,
or the apparatus.
Calibration factor (CF)--See section 7.5.1.
Calibration standard--A solution prepared from stock solutions and/
or a secondary standards and containing the analytes of interest,
surrogates, and internal standards. This standard is used to model the
response of the GC instrument against analyte concentration.
Calibration verification--The process of confirming that the
response of the analytical system remains within specified limits of the
calibration.
Calibration verification standard--The standard (section 6.8.4) used
to verify calibration (sections 7.8 and 13.6).
Extraction Batch--A set of up to 20 field samples (not including QC
samples) started through the extraction process in a given 24-hour
shift. Each extraction batch of 20 or fewer samples must be accompanied
by a blank (section 8.5), a laboratory control sample (LCS, section
8.4), a matrix spike and duplicate (MS/MSD; section 8.3), resulting in a
minimum of five samples (1 field sample, 1 blank, 1 LCS, 1 MS, and 1
MSD) and a maximum of 24 samples (20 field samples, 1 blank, 1 LCS, 1
MS, and 1 MSD) for the batch. If greater than 20 samples are to be
extracted in a 24-hour shift, the samples must be separated into
extraction batches of 20 or fewer samples.
Field Duplicates--Two samples collected at the same time and place
under identical conditions, and treated identically throughout field and
laboratory procedures. Results of analyses the field duplicates provide
an estimate of the precision associated with sample collection,
preservation, and storage, as well as with laboratory procedures.
Field blank--An aliquot of reagent water or other reference matrix
that is placed in a sample container in the field, and treated as a
sample in all respects, including exposure to sampling site conditions,
storage, preservation, and all analytical procedures. The purpose of the
field blank is to determine if the field or sample transporting
procedures and environments have contaminated the sample. See also
``Blank.''
GC--Gas chromatograph or gas chromatography.
Gel-permeation chromatography (GPC)--A form of liquid chromatography
in which the analytes are separated based on exclusion from the solid
phase by size.
Internal standard--A compound added to an extract or standard
solution in a known amount and used as a reference for quantitation of
the analytes of interest and surrogates. Also see Internal standard
quantitation.
Internal standard quantitation--A means of determining the
concentration of an analyte of interest (Tables 1 and 2) by reference to
a compound not expected to be found in a sample.
IDC--Initial Demonstration of Capability (section 8.2); four
aliquots of a reference matrix spiked with the analytes of interest and
analyzed to establish the ability of the laboratory to generate
acceptable precision and recovery. An IDC is performed prior to the
first time this method is used and any time the method or
instrumentation is modified.
Laboratory Control Sample (LCS; laboratory fortified blank; section
8.4)--An aliquot of reagent water spiked with known quantities of the
analytes of interest and surrogates. The LCS is analyzed exactly like a
sample. Its purpose is to assure that the results produced by the
laboratory remain within the limits specified in this method for
precision and recovery.
Laboratory Fortified Sample Matrix--See Matrix spike.
Laboratory reagent blank--See blank.
[[Page 192]]
Matrix spike (MS) and matrix spike duplicate (MSD) (laboratory
fortified sample matrix and duplicate)--Two aliquots of an environmental
sample to which known quantities of the analytes of interest and
surrogates are added in the laboratory. The MS/MSD are prepared and
analyzed exactly like a field sample. Their purpose is to quantify any
additional bias and imprecision caused by the sample matrix. The
background concentrations of the analytes in the sample matrix must be
determined in a separate aliquot and the measured values in the MS/MSD
corrected for background concentrations.
May--This action, activity, or procedural step is neither required
nor prohibited.
May not--This action, activity, or procedural step is prohibited.
Method detection limit (MDL)--A detection limit determined by the
procedure at 40 CFR part 136, appendix B. The MDLs determined by EPA are
listed in Tables 1 and 2. As noted in section 1.6, use the MDLs in
Tables 1 and 2 in conjunction with current MDL data from the laboratory
actually analyzing samples to assess the sensitivity of this procedure
relative to project objectives and regulatory requirements (where
applicable).
Minimum level (ML)--The term ``minimum level'' refers to either the
sample concentration equivalent to the lowest calibration point in a
method or a multiple of the method detection limit (MDL), whichever is
higher. Minimum levels may be obtained in several ways: They may be
published in a method; they may be based on the lowest acceptable
calibration point used by a laboratory; or they may be calculated by
multiplying the MDL in a method, or the MDL determined by a laboratory,
by a factor of 3. For the purposes of NPDES compliance monitoring, EPA
considers the following terms to be synonymous: ``quantitation limit,''
``reporting limit,'' and ``minimum level.''
MS--Mass spectrometer or mass spectrometry.
Must--This action, activity, or procedural step is required.
Preparation blank--See blank.
Reagent water--Water demonstrated to be free from the analytes of
interest and potentially interfering substances at the MDLs for the
analytes in this method.
Regulatory compliance limit--A limit on the concentration or amount
of a pollutant or contaminant specified in a nationwide standard, in a
permit, or otherwise established by a regulatory/control authority.
Relative standard deviation (RSD)--The standard deviation times 100
divided by the mean. Also termed ``coefficient of variation.''
RF--Response factor. See section 7.6.2.
RPD--Relative percent difference.
RSD--See relative standard deviation.
Safety Data Sheet (SDS)--Written information on a chemical's
toxicity, health hazards, physical properties, fire, and reactivity,
including storage, spill, and handling precautions that meet the
requirements of OSHA, 29 CFR 1910.1200(g) and appendix D to Sec.
1910.1200. United Nations Globally Harmonized System of Classification
and Labelling of Chemicals (GHS), third revised edition, United Nations,
2009.
Should--This action, activity, or procedural step is suggested but
not required.
SPE--Solid-phase extraction; a sample extraction or extract cleanup
technique in which an analyte is selectively removed from a sample or
extract by passage over or through a material capable of reversibly
adsorbing the analyte.
Stock solution--A solution containing an analyte that is prepared
using a reference material traceable to EPA, the National Institute of
Science and Technology (NIST), or a source that will attest to the
purity and authenticity of the reference material.
Surrogate--A compound unlikely to be found in a sample, which is
spiked into the sample in a known amount before extraction, and which is
quantified with the same procedures used to quantify other sample
components. The purpose of the surrogate is to monitor method
performance with each sample.
Method 609--Nitroaromatics and Isophorone
1. Scope and Application
1.1 This method covers the determination of certain nitroaromatics
and isophorone. The following parameters may be determined by this
method:
------------------------------------------------------------------------
Parameter STORET No. CAS No.
------------------------------------------------------------------------
2,4-Dinitrotoluene............................ 34611 121-14-2
2,6-Dinitrotoluene............................ 34626 606-20-2
Isophorone.................................... 34408 78-59-1
Nitrobenzene.................................. 34447 98-95-3
------------------------------------------------------------------------
1.2 This is a gas chromatographic (GC) method applicable to the
determination of the compounds listed above in municipal and industrial
discharges as provided under 40 CFR 136.1. When this method is used to
analyze unfamiliar samples for any or all of the compounds above,
compound identifications should be supported by at least one additional
qualitative technique. This method describes analytical conditions for a
second gas chromatographic column that can be used to confirm
measurements made with the primary column. Method 625 provides gas
chromatograph/mass spectrometer (GC/MS) conditions appropriate for the
qualitative and quantitative confirmation of results for all of the
parameters listed above, using the extract produced by this method.
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1.3 The method detection limit (MDL, defined in Section 14.1) \1\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
1.4 The sample extraction and concentration steps in this method are
essentially the same as in Methods 606, 608, 611, and 612. Thus, a
single sample may be extracted to measure the parameters included in the
scope of each of these methods. When cleanup is required, the
concentration levels must be high enough to permit selecting aliquots,
as necessary, to apply appropriate cleanup procedures. The analyst is
allowed the latitude, under Section 12, to select chromatographic
conditions appropriate for the simultaneous measurement of combinations
of these parameters.
1.5 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.6 This method is restricted to use by or under the supervision of
analysts experienced in the use of a gas chromatograph and in the
interpretation of gas chromatograms. Each analyst must demonstrate the
ability to generate acceptable results with this method using the
procedure described in Section 8.2.
2. Summary of Method
2.1 A measured volume of sample, approximately 1-L, is extracted
with methylene chloride using a separatory funnel. The methylene
chloride extract is dried and exchanged to hexane during concentration
to a volume of 10 mL or less. Isophorone and nitrobenzene are measured
by flame ionization detector gas chromatography (FIDGC). The
dinitrotoluenes are measured by electron capture detector gas
chromatography (ECDGC). \2\
2.2 The method provides a Florisil column cleanup procedure to aid
in the elimination of interferences that may be encountered.
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardware that lead to
discrete artifacts and/or elevated baseliles in gas chromatograms. All
of these materials must be routinely demonstrated to be free from
interferences under the conditions of the analysis by running laboratory
reagent blanks as described in Section 8.1.3.
3.1.1 Glassware must be scrupulously cleaned. \3\ Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed by detergent washing with
hot water, and rinses with tap water and distilled water. The glassware
should then be drained dry, and heated in a muffle furnace at 400 [deg]C
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not
be eliminated by this treatment. Solvent rinses with acetone and
pesticide quality hexane may be substituted for the muffle furnace
heating. Thorough rinsing with such solvents usually eliminates PCB
interference. Volumetric ware should not be heated in a muffle furnace.
After drying and cooling, glassware should be sealed and stored in a
clean environment to prevent any accumulation of dust or other
contaminants. Store inverted or capped with aluminum foil.
3.1.2 The use of high purity reagents and solvents helps to minimize
interference problems. Purification of solvents by distillation in all-
glass systems may be required.
3.2 Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary
considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled. The
cleanup procedure in Section 11 can be used to overcome many of these
interferences, but unique samples may require additional cleanup
approaches to achieve the MDL listed in Table 1.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified \4-6\ for
the information of the analyst.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--1-L or 1-qt, amber glass, fitted with a
screw cap lined with Teflon. Foil may be substituted for Teflon if the
sample is not corrosive. If amber bottles are not available, protect
samples from light. The bottle and cap liner must be washed, rinsed with
acetone or methylene chloride, and dried before use to minimize
contamination.
5.1.2 Automatic sampler (optional)--The sampler must incorporate
glass sample containers for the collection of a minimum of
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250 mL of sample. Sample containers must be kept refrigerated at 4
[deg]C and protected from light during compositing. If the sampler uses
a peristaltic pump, a minimum length of compressible silicone rubber
tubing may be used. Before use, however, the compressible tubing should
be thoroughly rinsed with methanol, followed by repeated rinsings with
distilled water to minimize the potential for contamination of the
sample. An integrating flow meter is required to collect flow
proportional composites.
5.2 Glassware (All specifications are suggested. Catalog numbers are
included for illustration only.):
5.2.1 Separatory funnel--2-L, with Teflon stopcock.
5.2.2 Drying column--Chromatographic column, approximately 400 mm
long x 19 mm ID, with coarse frit filter disc.
5.2.3 Chromatographic column--100 mm long x 10 mm ID, with Teflon
stopcock.
5.2.4 Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes K-
570050-1025 or equivalent). Calibration must be checked at the volumes
employed in the test. Ground glass stopper is used to prevent
evaporation of extracts.
5.2.5 Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
5.2.6 Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
5.2.7 Snyder column, Kuderna-Danish--Two-ball micro (Kontes K-
569001-0219 or equivalent).
5.2.8 Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
5.3 Boiling chips--Approximately 10/40 mesh. Heat to 400 [deg]C for
30 min or Soxhlet extract with methylene chloride.
5.4 Water bath--Heated, with concentric ring cover, capable of
temperature control (2 [deg]C). The bath should be
used in a hood.
5.5 Balance--Analytical, capable of accurately weighing 0.0001 g.
5.6 Gas chromatograph--An analytical system complete with gas
chromatograph suitable for on-column injection and all required
accessories including syringes, analytical columns, gases, detector, and
strip-chart recorder. A data system is recommended for measuring peak
areas.
5.6.1 Column 1--1.2 m long x 2 or 4 mm ID glass, packed with 1.95%
QF-1/1.5% OV-17 on Gas-Chrom Q (80/100 mesh) or equivalent. This column
was used to develop the method performance statements given in Section
14. Guidelines for the use of alternate column packings are provided in
Section 12.1.
5.6.2 Column 2--3.0 m long x 2 or 4 mm ID glass, packed with 3% OV-
101 on Gas-Chrom Q (80/100 mesh) or equivalent.
5.6.3 Detectors--Flame ionization and electron capture detectors.
The flame ionization detector (FID) is used when determining isophorone
and nitrobenzene. The electron capture detector (ECD) is used when
determining the dinitrotoluenes. Both detectors have proven effective in
the analysis of wastewaters and were used in develop the method
performance statements in Section 14. Guidelines for the use to
alternate detectors are provided in Section 12.1.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.2 Sodium hydroxide solution (10 N)--Dissolve 40 g of NaOH (ACS) in
reagent water and dilute to 100 mL.
6.3 Sulfuric acid (1 + 1)--Slowly, add 50 mL of
H2SO4 (ACS, sp. gr. 1.84) to 50 mL of reagent
water.
6.4 Acetone, hexane, methanol, methylene chloride--Pesticide quality
or equivalent.
6.5 Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at
400 [deg]C for 4 h in a shallow tray.
6.6 Florisil--PR grade (60/100 mesh). Purchase activated at 1250
[deg]F and store in dark in glass containers with ground glass stoppers
or foil-lined screw caps. Before use, activate each batch at least 16 h
at 200 [deg]C in a foil-covered glass container and allow to cool.
6.7 Stock standard solutions (1.00 [micro]g/[micro]L)--Stock
standard solutions can be prepared from pure standard materials or
purchased as certified solutions.
6.7.1 Prepare stock standard solutions by accurately weighing about
0.0100 g of pure material. Dissolve the material in hexane and dilute to
volume in a 10-mL volumetric flask. Larger volumes can be used at the
convenience of the analyst. When compound purity is assayed to be 96% or
greater, the weight can be used without correction to calculate the
concentration of the stock standard. Commercially prepared stock
standards can be used at any concentration if they are certified by the
manufacturer or by an independent source.
6.7.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles. Store at 4 [deg]C and protect from light. Stock
standard solutions should be checked frequently for signs of degradation
or evaporation, especially just prior to preparing calibration standards
from them.
6.7.3 Stock standard solutions must be replaced after six months, or
sooner if comparison with check standards indicates a problem.
6.8 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Establish gas chromatographic operating conditions equivalent to
those given in
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Table 1. The gas chromatographic system can be calibrated using the
external standard technique (Section 7.2) or the internal standard
technique (Section 7.3).
7.2 External standard calibration procedure:
7.2.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask and diluting to volume
with hexane. One of the external standards should be at a concentration
near, but above, the MDL (Table 1) and the other concentrations should
correspond to the expected range of concentrations found in real samples
or should define the working range of the detector.
7.2.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against the mass injected. The results can be used to prepare
a calibration curve for each compound. Alternatively, if the ratio of
response to amount injected (calibration factor) is a constant over the
working range (<10% relative standard deviation, RSD) linearity through
the origin can be assumed and the average ratio or calibration factor
can be used in place of a calibration curve.
7.3 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the compounds of interest. The analyst must
further demonstrate that the measurement of the internal standard is not
affected by method or matrix interferences. Because of these
limitations, no internal standard can be suggested that is applicable to
all samples.
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flash. To each calibration
standard, add a known constant amount of one or more internal standards,
and dilute to volume with hexane. One of the standards should be at a
concentration near, but above, the MDL and the other concentrations
should correspond to the expected range of concentrations found in real
samples or should define the working range of the detector.
7.3.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against concentration for each compound and internal standard.
Calculate response factors (RF) for each compound using Equation 1.
Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.110
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Cis = Concentration of the internal standard ([micro]g/L).
Cs = Concentration of the parameter to be measured ([micro]g/
L).
If the RF value over the working range is a constant (<10% RSD), the
RF can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.4 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of one or more
calibration standards. If the response for any parameter varies from the
predicted response by more than 15%, a new
calibration curve must be prepared for that compound.
7.5 Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the reagents.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Sections 10.4, 11.1, and 12.1) to improve the separations or lower the
cost of measurements. Each time such a modification is made to the
method, the analyst is required to repeat the procedure in Section 8.2.
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8.1.3 Before processing any samples, the analyst must analyze a
reagent water blank to demonstrate that interferences from the
analytical system and glassware are under control. Each time a set of
samples is extracted or reagents are changed, a reagent water blank must
be processed as a safeguard against laboratory contamination.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1,5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing each parameter of interest in acetone at a concentration of
20 [micro]g/mL for each dinitrotoluene and 100 [micro]g/mL for
isophorone and nitrobenzene. The QC check sample concentrate must be
obtained from the U.S. Environmental Protection Agency, Environmental
Monitoring and Support Laboratory in Cincinnati, Ohio, if available. If
not available from that source, the QC check sample concentrate must be
obtained from another external source. If not available from either
source above, the QC check sample concentrate must be prepared by the
laboratory using stock standards prepared independently from those used
for calibration.
8.2.2 Using a pipet, prepare QC check samples at the test
concentrations shown in Table 2 by adding 1.00 mL of QC check sample
concentrate to each of four 1-L aliquots of reagent water.
8.2.3 Analyze the well-mixed QC check samples according to the
method beginning in Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 2. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If any individual s exceeds the precision limit or
any individual X falls outside the range for accuracy, the system
performance is unacceptable for that parameter. Locate and correct the
source of the problem and repeat the test for all parameters of interest
beginning with Section 8.2.2.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at the test concentration in Section 8.2.2 or 1 to 5
times higher than the background concentration determined in Section
8.3.2, whichever concentration would be larger.
8.3.1.3 If it is impractical to determile background levels before
spiking (e.g., maximum holding times will be exceeded), the spike
concentration should be (1) the regulatory concentration limit, if any;
or, if none (2) the larger of either 5 times higher than the expected
background concentration or the test concentration in Section 8.2.2.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second sample aliquot with 1.0 mL
of the QC check sample concentrate and analyze it to determine the
concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100 (A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 2. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\7\ If spiking was performed at a concentration lower than the test
concentration in Section 8.2.2, the analyst must use either the QC
acceptance criteria in Table 2, or optional QC acceptance criteria
calculated for the specific spike concentration. To calculate optional
acceptance criteria for the recovery of a parameter: (1)
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Calculate accuracy (X') using the equation in Table 3, substituting the
spike concentration (T) for C; (2) calculate overall precision (S')
using the equation in Table 3, substituting X' for X8; (3) calculate the
range for recovery at the spike concentration as (100 X'/T) 2.44 (100 S'/T)%. \7\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4. If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory.
8.4.1 Prepare the QC check standard by adding 1.0 mL of QC check
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The
QC check standard needs only to contain the parameters that failed
criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
2. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of QC program for the laboratory, method accuracy for
wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2sp to P + 2sp.
If P = 90% and sp = 10%, for example, the accuracy interval
is expressed as 70-110%. Update the accuracy assessment for each
parameter on a regular basis (e.g. after each five to ten new accuracy
measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as gas chromatography with a dissimilar column, specific element
detector, or mass spectrometer must be used. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevant performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices \8\ should be followed, except that the bottle must
not be prerinsed with sample before collection. Composite samples should
be collected in refrigerated glass containers in accordance with the
requirements of the program. Automatic sampling equipment must be as
free as possible of Tygon tubing and other potential sources of
contamination.
9.2 All samples must be iced or refrigerated at 4 [deg]C from the
time of collection until extraction.
9.3 All samples must be extracted within 7 days of collection and
completely analyzed within 40 days of extraction. \2\
10. Sample Extraction
10.1 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Pour the entire sample into a 2-L
separatory funnel. Check the pH of the sample with wide-range pH paper
and adjust to within the range of 5 to 9 with sodium hydroxide solution
or sulfuric acid.
10.2 Add 60 mL of methylene chloride to the sample bottle, seal, and
shake 30 s to rinse the inner surface. Transfer the solvent to the
separatory funnel and extract the sample by shaking the funnel for 2
min. with periodic venting to release excess pressure. Allow the organic
layer to separate from the water phase for a minimum of 10 min. If the
emulsion interface between layers is more than one-third the volume of
the solvent layer, the analyst must employ mechanical techniques to
complete the phase separation. The optimum technique depends upon the
sample, but may include stirring, filtration of the emulsion through
glass wool, centrifugation, or other physical methods. Collect the
methylene chloride extract in a 250-mL Erlenmeyer flask.
10.3 Add a second 60-mL volume of methylene chloride to the sample
bottle and repeat the extraction procedure a second time, combining the
extracts in the Erlenmeyer flask. Perform a third extraction in the same
manner.
[[Page 198]]
10.4 Assemble a Kuderna-Danish (K-D) concentrator by attaching a 10-
mL concentrator tube to a 500-mL evaporative flask. Other concentration
devices or techniques may be used in place of the K-D concentrator if
the requirements of Section 8.2 are met.
10.5 Pour the combined extract through a solvent-rinsed drying
column containing about 10 cm of anhydrous sodium sulfate, and collect
the extract in the K-D concentrator. Rinse the Erlenmeyer flask and
column with 20 to 30 mL of methylene chloride to complete the
quantitative transfer.
10.6 Sections 10.7 and 10.8 describe a procedure for exchanging the
methylene chloride solvent to hexane while concentrating the extract
volume to 1.0 mL. When it is not necessary to achieve the MDL in Table
2, the solvent exchange may be made by the addition of 50 mL of hexane
and concentration to 10 mL as described in Method 606, Sections 10.7 and
10.8.
10.7 Add one or two clean boiling chips to the evaporative flask and
attach a three-ball Snyder column. Prewet the Snyder column by adding
about 1 mL of methylene chloride to the top. Place the K-D apparatus on
a hot water bath (60 to 65 [deg]C) so that the concentrator tube is
partially immersed in the hot water, and the entire lower rounded
surface of the flask is bathed with hot vapor. Adjust the vertical
position of the apparatus and the water temperature as required to
complete the concentration in 15 to 20 min. At the proper rate of
distillation the balls of the column will actively chatter but the
chambers will not flood with condensed solvent. When the apparent volume
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain
and cool for at least 10 min.
10.8 Remove the Snyder column and rinse the flask and its lower
joint into the concentrator tube with 1 to 2 mL of methylene chloride. A
5-mL syringe is recommended for this operation. Add 1 to 2 mL of hexane
and a clean boiling chip to the concentrator tube and attach a two-ball
micro-Snyder column. Prewet the column by adding about 0.5 mL of hexane
to the top. Place the micro-K-D apparatus on a hot water bath (60 to 65
[deg]C) so that the concentrator tube is partially immersed in the hot
water. Adjust the vertical position of the apparatus and the water
temperature as required to complete the concentration in 5 to 10 min. At
the proper rate of distillation the balls of the column will actively
chatter but the chambers will not flood. When the apparent volume of
liquid reaches 0.5 mL, remove the K-D apparatus and allow it to drain
and cool for at least 10 min.
10.9 Remove the micro-Snyder column and rinse its lower joint into
the concentrator tube with a minimum amount of hexane. Adjust the
extract volume to 1.0 mL. Stopper the concentrator tube and store
refrigerated if further processing will not be performed immediately. If
the extract will be stored longer than two days, it should be
transferred to a Teflon-sealed screw-cap vial. If the sample extract
requires no further cleanup, proceed with gas chromatographic analysis
(Section 12). If the sample requires further cleanup, proceed to Section
11.
10.10 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to a 1000-mL graduated
cylinder. Record the sample volume to the nearest 5 mL.
11. Cleanup and Separation
11.1 Cleanup procedures may not be necessary for a relatively clean
sample matrix. If particular circumstances demand the use of a cleanup
procedure, the analyst may use the procedure below or any other
appropriate procedure. However, the analyst first must demonstrate that
the requirements of Section 8.2 can be met using the method as revised
to incorporate the cleanup procedure.
11.2 Florisil column cleanup:
11.2.1 Prepare a slurry of 10 g of activated Florisil in methylene
chloride/hexane (1 + 9)(V/V) and place the Florisil into a
chromatographic column. Tap the column to settle the Florisil and add 1
cm of anhydrous sodium sulfate to the top. Adjust the elution rate to
about 2 mL/min.
11.2.2 Just prior to exposure of the sodium sulfate layer to the
air, quantitatively transfer the sample extract onto the column using an
additional 2 mL of hexane to complete the transfer. Just prior to
exposure of the sodium sulfate layer to the air, add 30 mL of methylene
chloride/hexane (1 + 9)(V/V) and continue the elution of the column.
Discard the eluate.
11.2.3 Next, elute the column with 30 mL of acetone/methylene
chloride (1 + 9)(V/V) into a 500-mL K-D flask equipped with a 10-mL
concentrator tube. Concentrate the collected fraction as in Sections
10.6, 10.7, 10.8, and 10.9 including the solvent exchange to 1 mL of
hexane. This fraction should contain the nitroaromatics and isophorone.
Analyze by gas chromatography (Section 12).
12. Gas Chromatography
12.1 Isophorone and nitrobenzene are analyzed by injection of a
portion of the extract into an FIDGC. The dinitrotoluenes are analyzed
by a separate injection into an ECDGC. Table 1 summarizes the
recommended operating conditions for the gas chromatograph. Included in
this table are retention times and MDL that can be achieved under these
conditions. Examples of the separations achieved by Column 1 are shown
in Figures 1 and 2. Other packed or capillary (open-tubular) columns,
chromatographic conditions, or detectors may be used if the requirements
of Section 8.2 are met.
12.2 Calibrate the system daily as described in Section 7.
[[Page 199]]
12.3 If the internal standard calibration procedure is being used,
the internal standard must be added to the same extract and mixed
thoroughly immediately before injection into the gas chromatograph.
12.4 Inject 2 to 5 [micro]L of the sample extract or standard into
the gas chromatograph using the solvent-flush technique. \9\ Smaller
(1.0 [micro]L) volumes may be injected if automatic devices are
employed. Record the volume injected to the nearest 0.05 [micro]L, the
total extract volume, and the resulting peak size in area or peak height
units.
12.5 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
12.6 If the response for a peak exceeds the working range of the
system, dilute the extract and reanalyze.
12.7 If the measurement of the peak response is prevented by the
presence of interferences, further cleanup is required.
13. Calculations
13.1 Determine the concentration of individual compounds in the
sample.
13.1.1 If the external standard calibration procedure is used,
calculate the amount of material injected from the peak response using
the calibration curve or calibration factor determined in Section 7.2.2.
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.111
Equation 2
where:
A = Amount of material injected (ng).
Vi = Volume of extract injected ([micro]L).
Vt = Volume of total extract ([micro]L).
Vs = Volume of water extracted (mL).
13.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.112
Equation 3
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Is = Amount of internal standard added to each extract
([micro]g).
Vo = Volume of water extracted (L).
13.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
14. Method Performance
14.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentrations
listed in Table 1 were obtained using reagent water. \10\ Similar
results were achieved using representative wastewaters. The MDL actually
achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
14.2 This method has been tested for linearity of spike recovery
from reagent water and has been demonstrated to be applicable over the
concentration range from 7 x MDL to 1000 x MDL. \10\
14.3 This method was tested by 18 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
at six concentrations over the range 1.0 to 515 [micro]g/L. \11\ Single
operator precision, overall precision, and method accuracy were found to
be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 3.
References
1. 40 CFR part 136, appendix B.
2. ``Determination of Nitroaromatic Compounds and Isophorone in
Industrial and Municipal Wastewaters,'' EPA 600/ 4-82-024, National
Technical Information Service, PB82-208398, Springfield, Virginia 22161,
May 1982.
3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard
Practices for Preparation of Sample Containers and for Preservation of
Organic Constituents,'' American Society for Testing and Materials,
Philadelphia.
4. ``Carcinogens--Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
[[Page 200]]
6. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value 1.22
derived in this report.)
8. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard
Practices for Sampling Water,'' American Society for Testing and
Materials, Philadelphia.
9. Burke, J.A. ``Gas Chromatography for Pesticide Residue Analysis;
Some Practical Aspects,'' Journal of the Association of Official
Analytical Chemists, 48, 1037 (1965).
10. ``Determination of Method Detection Limit and Analytical Curve
for EPA Method 609--Nitroaromatics and Isophorone,'' Special letter
report for EPA Contract 68-03-2624, U.S. Environmental Protection
Agency, Environmental Monitoring and Support Laboratory, Cincinnati,
Ohio 45268, June 1980.
11. ``EPA Method Study 19, Method 609 (Nitroaromatics and
Isophorone),'' EPA 600/4-84-018, National Technical Information Service,
PB84-176908, Springfield, Virginia 22161, March 1984.
Table 1--Chromatographic Conditions and Method Detection Limits
----------------------------------------------------------------------------------------------------------------
Retention time (min) Method detection limit
---------------------------- ([micro]g/L)
Parameter ---------------------------
Col. 1 Col. 2 ECDGC FIDGC
----------------------------------------------------------------------------------------------------------------
Nitrobenzene............................................ 3.31 4.31 13.7 3.6
2,6-Dinitrotoluene...................................... 3.52 4.75 0.01 -
Isophorone.............................................. 4.49 5.72 15.7 5.7
2,4-Dinitrotoluene...................................... 5.35 6.54 0.02 -
----------------------------------------------------------------------------------------------------------------
Column 1 conditions: Gas-Chrom Q (80/100 mesh) coated with 1.95% QF-1/1.5% OV-17 packed in a 1.2 m long x 2 mm
or 4 mm ID glass column. A 2 mm ID column and nitrogen carrier gas at 44 mL/min flow rate were used when
determining isophorone and nitrobenzene by FIDGC. The column temperature was held isothermal at 85 [deg]C. A 4
mm ID column and 10% methane/90% argon carrier gas at 44 mL/min flow rate were used when determining the
dinitrotoluenes by ECDGC. The column temperature was held isothermal at 145 [deg]C.
Column 2 conditions: Gas-Chrom Q (80/100 mesh) coated with 3% OV-101 packed in a 3.0 m long x 2 mm or 4 mm ID
glass column. A 2 mm ID column and nitrogen carrier gas at 44 mL/min flow rate were used when determining
isophorone and nitrobenzene by FIDGC. The column temperature was held isothermal at 100 [deg]C. A 4 mm ID
column and 10% methane/90% argon carrier gas at 44 mL/min flow rate were used when determining the
dinitrotoluenes by ECDGC. The column temperature was held isothermal at 150 [deg]C.
Table 2--QC Acceptance Criteria--Method 609
----------------------------------------------------------------------------------------------------------------
Test Conc.
Parameter ([micro]g/ Limit for s Range for X Range for
L) ([micro]g/L) ([micro]g/L) P, Ps (%)
----------------------------------------------------------------------------------------------------------------
2,4-Dinitrotoluene........................................ 20 5.1 3.6-22.8 6-125
2,6-Dinitrotoluene........................................ 20 4.8 3.8-23.0 8-126
Isophorone................................................ 100 32.3 8.0-100.0 D-117
Nitrobenzene.............................................. 100 33.3 25.7-100.0 6-118
----------------------------------------------------------------------------------------------------------------
s = Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X = Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps = Percent recovery measured (Section 8.3.2, Section 8.4.2).
D = Detected; result must be greater than zero.
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 3.
Table 3--Method Accuracy and Precision as Functions of Concentration--Method 609
----------------------------------------------------------------------------------------------------------------
Accuracy, as Single analyst Overall
Parameter recovery, X' precision, sr' precision, S'
([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
2,4-Dinitro-
toluene............................................... 0.65C + 0.22 0.20X + 0.08 0.37X-0.07
2,6-Dinitro-
toluene............................................... 0.66C + 0.20 0.19X + 0.06 0.36X-0.00
Isophorone............................................. 0.49C + 2.93 0.28X + 2.77 0.46X + 0.31
Nitrobenzene........................................... 0.60C + 2.00 0.25X + 2.53 0.37X-0.78
----------------------------------------------------------------------------------------------------------------
X' = Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/L.
sr' = Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S' = Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C = True value for the concentration, in [micro]g/L.
X = Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
[[Page 201]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.029
[[Page 202]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.030
[[Page 203]]
Method 610--Polynuclear Aromatic Hydrocarbons
1. Scope and Application
1.1 This method covers the determination of certain polynuclear
aromatic hydrocarbons (PAH). The following parameters can be determined
by this method:
------------------------------------------------------------------------
Parameter STORET No. CAS No.
------------------------------------------------------------------------
Acenaphthene................................ 34205 83-32-9
Acenaphthylene.............................. 34200 208-96-8
Anthracene.................................. 34220 120-12-7
Benzo(a)anthracene.......................... 34526 56-55-3
Benzo(a)pyrene.............................. 34247 50-32-8
Benzo(b)fluoranthene........................ 34230 205-99-2
Benzo(ghi)perylene.......................... 34521 191-24-2
Benzo(k)fluoranthene........................ 34242 207-08-9
Chrysene.................................... 34320 218-01-9
Dibenzo(a,h)anthracene...................... 34556 53-70-3
Fluoranthene................................ 34376 206-44-0
Fluorene.................................... 34381 86-73-7
Indeno(1,2,3-cd)pyrene...................... 34403 193-39-5
Naphthalene................................. 34696 91-20-3
Phenanthrene................................ 34461 85-01-8
Pyrene...................................... 34469 129-00-0
------------------------------------------------------------------------
1.2 This is a chromatographic method applicable to the determination
of the compounds listed above in municipal and industrial discharges as
provided under 40 CFR 136.1. When this method is used to analyze
unfamiliar samples for any or all of the compounds above, compound
identifications should be supported by at least one additional
qualitative technique. Method 625 provides gas chromatograph/mass
spectrometer (GC/MS) conditions appropriate for the qualitative and
quantitative confirmation of results for many of the parameters listed
above, using the extract produced by this method.
1.3 This method provides for both high performance liquid
chromatographic (HPLC) and gas chromatographic (GC) approaches for the
determination of PAHs. The gas chromatographic procedure does not
adequately resolve the following four pairs of compounds: Anthracene and
phenanthrene; chrysene and benzo(a)anthracene; benzo(b)fluoranthene and
benzo(k)fluoranthene; and dibenzo(a,h) anthracene and indeno (1,2,3-
cd)pyrene. Unless the purpose for the analysis can be served by
reporting the sum of an unresolved pair, the liquid chromatographic
approach must be used for these compounds. The liquid chromatographic
method does resolve all 16 of the PAHs listed.
1.4 The method detection limit (MDL, defined in Section 15.1) \1\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
1.5 The sample extraction and concentration steps in this method are
essentially the same as in Methods 606, 608, 609, 611, and 612. Thus, a
single sample may be extracted to measure the parameters included in the
scope of each of these methods. When cleanup is required, the
concentration levels must be high enough to permit selecting aliquots,
as necessary, to apply appropriate cleanup procedures. Selection of the
aliquots must be made prior to the solvent exchange steps of this
method. The analyst is allowed the latitude, under Sections 12 and 13,
to select chromatographic conditions appropriate for the simultaneous
measurement of combinations of these parameters.
1.6 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.7 This method is restricted to use by or under the supervision of
analysts experienced in the use of HPLC and GC systems and in the
interpretation of liquid and gas chromatograms. Each analyst must
demonstrate the ability to generate acceptable results with this method
using the procedure described in Section 8.2.
2. Summary of Method
2.1 A measured volume of sample, approximately 1-L, is extracted
with methylene chloride using a separatory funnel. The methylene
chloride extract is dried and concentrated to a volume of 10 mL or less.
The extract is then separated by HPLC or GC. Ultraviolet (UV) and
fluorescence detectors are used with HPLC to identify and measure the
PAHs. A flame ionization detector is used with GC. \2\
2.2 The method provides a silica gel column cleanup procedure to aid
in the elimination of interferences that may be encountered.
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardward that lead to
discrete artifacts and/or elevated baselines in the chromatograms. All
of these materials must be routinely demonstrated to be free from
interferences under the conditions of the analysis by running laboratory
reagent blanks as described in Section 8.1.3.
3.1.1 Glassware must be scrupulously cleaned. \3\ Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed by detergent washing with
hot water, and rinses with tap water and distilled water. The glassware
should then be drained dry, and heated in a muffle furnace at 400 [deg]C
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not
be eliminated by this treatment. Solvent rinses with acetone and
pesticide quality hexane may be
[[Page 204]]
substituted for the muffle furnace heating. Thorough rinsing with such
solvents usually eliminates PCB interference. Volumetric ware should not
be heated in a muffle furnace. After drying and cooling, glassware
should be sealed and stored in a clean environment to prevent any
accumulation of dust or other contaminants. Store inverted or capped
with aluminum foil.
3.1.2 The use of high purity reagents and solvents helps to minimize
interference problems. Purification of solvents by distillation in all-
glass systems may be required.
3.2 Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary
considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled. The
cleanup procedure in Section 11 can be used to overcome many of these
interferences, but unique samples may require additional cleanup
approaches to achieve the MDL listed in Table 1.
3.3 The extent of interferences that may be encountered using liquid
chromatographic techniques has not been fully assessed. Although the
HPLC conditions described allow for a unique resolution of the specific
PAH compounds covered by this method, other PAH compounds may interfere.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method have not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified \4-6\ for
the information of the analyst.
4.2 The following parameters covered by this method have been
tentatively classified as known or suspected, human or mammalian
carcinogens: benzo(a)anthracene, benzo(a)pyrene, and dibenzo(a,h)-
anthracene. Primary standards of these toxic compounds should be
prepared in a hood. A NIOSH/MESA approved toxic gas respirator should be
worn when the analyst handles high concentrations of these toxic
compounds.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--1-L or 1-qt, amber glass, fitted with a
screw cap lined with Teflon. Foil may be substituted for Teflon if the
sample is not corrosive. If amber bottles are not available, protect
samples from light. The bottle and cap liner must be washed, rinsed with
acetone or methylene chloride, and dried before use to minimize
contamination.
5.1.2 Automatic sampler (optional)--The sampler must incorporate
glass sample containers for the collection of a minimum of 250 mL of
sample. Sample containers must be kept refrigerated at 4 [deg]C and
protected from light during compositing. If the sampler uses a
peristaltic pump, a minimum length of compressible silicone rubber
tubing may be used. Before use, however, the compressible tubing should
be thoroughly rinsed with methanol, followed by repeated rinsings with
distilled water to minimize the potential for contamination of the
sample. An integrating flow meter is required to collect flow
proportional composites.
5.2 Glassware (All specifications are suggested. Catalog numbers are
included for illustration only.):
5.2.1 Separatory funnel--2-L, with Teflon stopcock.
5.2.2 Drying column--Chromatographic column, approximately 400 mm
long x 19 mm ID, with coarse frit filter disc.
5.2.3 Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes K-
570050-1025 or equivalent). Calibration must be checked at the volumes
employed in the test. Ground glass stopper is used to prevent
evaporation of extracts.
5.2.4 Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
5.2.5 Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
5.2.6 Snyder column, Kuderna-Danish--Two-ball micro (Kontes K-
569001-0219 or equivalent).
5.2.7 Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
5.2.8 Chromatographic column--250 mm long x 10 mm ID, with coarse
frit filter disc at bottom and Teflon stopcock.
5.3 Boiling chips--Approximately 10/40 mesh. Heat to 400 [deg]C for
30 min or Soxhlet extract with methylene chloride.
5.4 Water bath--Heated, with concentric ring cover, capable of
temperature control (2 [deg]C). The bath should be
used in a hood.
5.5 Balance--Analytical, capable of accurately weighing 0.0001 g.
5.6 High performance liquid chromatograph (HPLC)--An analytical
system complete with column supplies, high pressure syringes, detectors,
and compatible strip-chart recorder. A data system is recommended for
measuring peak areas and retention times.
5.6.1 Gradient pumping system--Constant flow.
[[Page 205]]
5.6.2 Reverse phase column--HC-ODS Sil-X, 5 micron particle
diameter, in a 25 cm x 2.6 mm ID stainless steel column (Perkin Elmer
No. 089-0716 or equivalent). This column was used to develop the method
performance statements in Section 15. Guidelines for the use of
alternate column packings are provided in Section 12.2.
5.6.3 Detectors--Fluorescence and/or UV detectors. The fluorescence
detector is used for excitation at 280 nm and emission greater than 389
nm cutoff (Corning 3-75 or equivalent). Fluorometers should have
dispersive optics for excitation and can utilize either filter or
dispersive optics at the emission detector. The UV detector is used at
254 nm and should be coupled to the fluorescence detector. These
detectors were used to develop the method performance statements in
Section 15. Guidelines for the use of alternate detectors are provided
in Section 12.2.
5.7 Gas chromatograph--An analytical system complete with
temperature programmable gas chromatograph suitable for on-column or
splitless injection and all required accessories including syringes,
analytical columns, gases, detector, and strip-chart recorder. A data
system is recommended for measuring peak areas.
5.7.1 Column--1.8 m long x 2 mm ID glass, packed with 3% OV-17 on
Chromosorb W-AW-DCMS (100/120 mesh) or equivalent. This column was used
to develop the retention time data in Table 2. Guidelines for the use of
alternate column packings are provided in Section 13.3.
5.7.2 Detector--Flame ionization detector. This detector has proven
effective in the analysis of wastewaters for the parameters listed in
the scope (Section 1.1), excluding the four pairs of unresolved
compounds listed in Section 1.3. Guidelines for the use of alternate
detectors are provided in Section 13.3.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.2 Sodium thiosulfate--(ACS) Granular.
6.3 Cyclohexane, methanol, acetone, methylene chloride, pentane--
Pesticide quality or equivalent.
6.4 Acetonitrile--HPLC quality, distilled in glass.
6.5 Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at
400 [deg]C for 4 h in a shallow tray.
6.6 Silica gel--100/200 mesh, desiccant, Davison, grade-923 or
equivalent. Before use, activate for at least 16 h at 130 [deg]C in a
shallow glass tray, loosely covered with foil.
6.7 Stock standard solutions (1.00 [micro]g/[micro]L)--Stock
standard solutions can be prepared from pure standard materials or
purchased as certified solutions.
6.7.1 Prepare stock standard solutions by accurately weighing about
0.0100 g of pure material. Dissolve the material in acetonitrile and
dilute to volume in a 10-mL volumetric flask. Larger volumes can be used
at the convenience of the analyst. When compound purity is assayed to be
96% or greater, the weight can be used without correction to calculate
the concentration of the stock standard. Commercially prepared stock
standards can be used at any concentration if they are certified by the
manufacturer or by an independent source.
6.7.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles. Store at 4 [deg]C and protect from light. Stock
standard solutions should be checked frequently for signs of degradation
or evaporation, especially just prior to preparing calibration standards
from them.
6.7.3 Stock standard solutions must be replaced after six months, or
sooner if comparison with check standards indicates a problem.
6.8 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Establish liquid or gas chromatographic operating conditions
equivalent to those given in Table 1 or 2. The chromatographic system
can be calibrated using the external standard technique (Section 7.2) or
the internal standard technique (Section 7.3).
7.2 External standard calibration procedure:
7.2.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask and diluting to volume
with acetonitrile. One of the external standards should be at a
concentration near, but above, the MDL (Table 1) and the other
concentrations should correspond to the expected range of concentrations
found in real samples or should define the working range of the
detector.
7.2.2 Using injections of 5 to 25 [micro]L for HPLC and 2 to 5
[micro]L for GC, analyze each calibration standard according to Section
12 or 13, as appropriate. Tabulate peak height or area responses against
the mass injected. The results can be used to prepare a calibration
curve for each compound. Alternatively, if the ratio of response to
amount injected (calibration factor) is a constant over the working
range (<10% relative standard deviation, RSD), linearity through the
origin can be assumed and the average ratio or calibration factor can be
used in place of a calibration curve.
7.3 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the
[[Page 206]]
compounds of interest. The analyst must further demonstrate that the
measurement of the internal standard is not affected by method or matrix
interferences. Because of these limitations, no internal standard can be
suggested that is applicable to all samples.
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask. To each calibration
standard, add a known constant amount of one or more internal standards,
and dilute to volume with acetonitrile. One of the standards should be
at a concentration near, but above, the MDL and the other concentrations
should correspond to the expected range of concentrations found in real
samples or should define the working range of the detector.
7.3.2 Using injections of 5 to 25 [micro]L for HPLC and 2 to 5
[micro]L for GC, analyze each calibration standard according to Section
12 or 13, as appropriate. Tabulate peak height or area responses against
concentration for each compound and internal standard. Calculate
response factors (RF) for each compound using Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.113
Equation 1
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Cis = Concentration of the internal standard ([micro]g/L).
Cs = Concentration of the parameter to be measured ([micro]g/
L).
If the RF value over the working range is a constant (<10% RSD), the RF
can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.4 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of one or more
calibration standards. If the response for any parameter varies from the
predicted response by more than 15%, the test must
be repeated using a fresh calibration standard. Alternatively, a new
calibration curve must be prepared for that compound.
7.5 Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the reagents.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Sections 10.4, 11.1, 12.2, and 13.3) to improve the separations or lower
the cost of measurements. Each time such a modification is made to the
method, the analyst is required to repeat the procedure in Section 8.2.
8.1.3 Before processing any samples the analyst must analyze a
reagent water blank to demonstrate that interferences from the
analytical system and glassware are under control. Each time a set of
samples is extracted or reagents are changed a reagent water blank must
be processed as a safeguard against laboratory contamination.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing each parameter of interest at the following concentrations in
acetonitrile: 100 [micro]g/mL of any
[[Page 207]]
of the six early-eluting PAHs (naphthalene, acenaphthylene,
acenaphthene, fluorene, phenanthrene, and anthracene); 5 [micro]g/mL of
benzo(k)fluoranthene; and 10 [micro]g/mL of any of the other PAHs. The
QC check sample concentrate must be obtained from the U.S. Environmental
Protection Agency, Environmental Monitoring and Support Laboratory in
Cincinnati, Ohio, if available. If not available from that source, the
QC check sample concentrate must be obtained from another external
source. If not available from either source above, the QC check sample
concentrate must be prepared by the laboratory using stock standards
prepared independently from those used for calibration.
8.2.2 Using a pipet, prepare QC check samples at the test
concentrations shown in Table 3 by adding 1.00 mL of QC check sample
concentrate to each of four 1-L aliquots of reagent water.
8.2.3 Analyze the well-mixed QC check samples according to the
method beginning in Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 3. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If any individual s exceeds the precision limit or
any individual X falls outside the range for accuracy, the system
performance is unacceptable for that parameter.
Note: The large number of parameters in Table 3 present a
substantial probability that one or more will fail at least one of the
acceptance criteria when all parameters are analyzed.
8.2.6 When one or more of the parameters tested fail at least one of
the acceptance criteria, the analyst must proceed according to Section
8.2.6.1 or 8.2.6.2.
8.2.6.1 Locate and correct the source of the problem and repeat the
test for all parameters of interest beginning with Section 8.2.2.
8.2.6.2 Beginning with Section 8.2.2, repeat the test only for those
parameters that failed to meet criteria. Repeated failure, however, will
confirm a general problem with the measurement system. If this occurs,
locate and correct the source of the problem and repeat the test for all
compounds of interest beginning with Section 8.2.2.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at the test concentration in Section 8.2.2 or 1 to 5
times higher than the background concentration determined in Section
8.3.2, whichever concentration would be larger.
8.3.1.3 If it is impractical to determine background levels before
spiking (e.g., maximum holding times will be exceeded), the spike
concentration should be (1) the regulatory concentration limit, if any;
or, if none, (2) the larger of either 5 times higher than the expected
background concentration or the test concentration in Section 8.2.2.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second sample aliquot with 1.0 mL
of the QC check sample concentrate and analyze it to determine the
concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100 (A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 3. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\7\ If spiking was performed at a concentration lower than the test
concentration in Section 8.2.2, the analyst must use either the QC
acceptance criteria in Table 3, or optional QC acceptance criteria
calculated for the specific spike concentration. To calculate optional
acceptance criteria for the recovery of a parameter: (1) Calculate
accuracy (X') using the equation in Table 4, substituting the spike
concentration (T) for C; (2) calculate overall precision (S') using the
equation in Table 4, substituting X' for X; (3) calculate the range for
recovery at the spike concentration as (100 X'/T)2.44(100 S'/T)%. \7\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter
[[Page 208]]
that failed the critiera must be analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory. If the entire list of parameters in Table 3 must be measured
in the sample in Section 8.3, the probability that the analysis of a QC
check standard will be required is high. In this case the QC check
standard should be routinely analyzed with the spike sample.
8.4.1 Prepare the QC check standard by adding 1.0 mL of QC check
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The
QC check standard needs only to contain the parameters that failed
criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
3. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P092sp to P +
2sp. If P = 90% and sp = 10%, for example, the
accuracy interval is expressed as 70-110%. Update the accuracy
assessment for each parameter on a regular basis (e.g. after each five
to ten new accuracy measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as gas chromatography with a dissimilar column, specific element
detector, or mass spectrometer must be used. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevant performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices \8\ should be followed, except that the bottle must
not be prerinsed with sample before collection. Composite samples should
be collected in refrigerated glass containers in accordance with the
requirements of the program. Automatic sampling equipment must be as
free as possible of Tygon tubing and other potential sources of
contamination.
9.2 All samples must be iced or refrigerated at 4 [deg]C from the
time of collection until extraction. PAHs are known to be light
sensitive; therefore, samples, extracts, and standards should be stored
in amber or foil-wrapped bottles in order to minimize photolytic
decomposition. Fill the sample bottles and, if residual chlorine is
present, add 80 mg of sodium thiosulfate per liter of sample and mix
well. EPA Methods 330.4 and 330.5 may be used for measurement of
residual chlorine. \9\ Field test kits are available for this purpose.
9.3 All samples must be extracted within 7 days of collection and
completely analyzed within 40 days of extraction. \2\
10. Sample Extraction
10.1 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Pour the entire sample into a 2-L
separatory funnel.
10.2 Add 60 mL of methylene chloride to the sample bottle, seal, and
shake 30 s to rinse the inner surface. Transfer the solvent to the
separatory funnel and extract the sample by shaking the funnel for 2
min. with periodic venting to release excess pressure. Allow the organic
layer to separate from the water phase for a minimum of 10 min. If the
emulsion interface between layers is more than one-third the volume of
the solvent layer, the analyst must employ mechanical techniques to
complete the phase separation. The optimum technique depends upon the
sample, but may include stirring, filtration of the emulsion through
glass wool, centrifugation, or other physical methods. Collect the
methylene chloride extract in a 250-mL Erlenmeyer flask.
10.3 Add a second 60-mL volume of methylene chloride to the sample
bottle and repeat the extraction procedure a second time, combining the
extracts in the Erlenmeyer flask. Perform a third extraction in the same
manner.
[[Page 209]]
10.4 Assemble a Kuderna-Danish (K-D) concentrator by attaching a 10-
mL concentrator tube to a 500-mL evaporative flask. Other concentration
devices or techniques may be used in place of the K-D concentrator if
the requirements of Section 8.2 are met.
10.5 Pour the combined extract through a solvent-rinsed drying
column containing about 10 cm of anhydrous sodium sulfate, and collect
the extract in the K-D concentrator. Rinse the Erlenmeyer flask and
column with 20 to 30 mL of methylene chloride to complete the
quantitative transfer.
10.6 Add one or two clean boiling chips to the evaporative flask and
attach a three-ball Snyder column. Prewet the Snyder column by adding
about 1 mL of methylene chloride to the top. Place the K-D apparatus on
a hot water bath (60 to 65 [deg]C) so that the concentrator tube is
partially immersed in the hot water, and the entire lower rounded
surface of the flask is bathed with hot vapor. Adjust the vertical
position of the apparatus and the water temperature as required to
complete the concentration in 15 to 20 min. At the proper rate of
distillation the balls of the column will actively chatter but the
chambers will not flood with condensed solvent. When the apparent volume
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain
and cool for at least 10 min.
10.7 Remove the Snyder column and rinse the flask and its lower
joint into the concentrator tube with 1 to 2 mL of methylene chloride. A
5-mL syringe is recommended for this operation. Stopper the concentrator
tube and store refrigerated if further processing will not be performed
immediately. If the extract will be stored longer than two days, it
should be transferred to a Teflon-sealed screw-cap vial and protected
from light. If the sample extract requires no further cleanup, proceed
with gas or liquid chromatographic analysis (Section 12 or 13). If the
sample requires further cleanup, proceed to Section 11.
10.8 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to a 1000-mL graduated
cylinder. Record the sample volume to the nearest 5 mL.
11. Cleanup and Separation
11.1 Cleanup procedures may not be necessary for a relatively clean
sample matrix. If particular circumstances demand the use of a cleanup
procedure, the analyst may use the procedure below or any other
appropriate procedure. However, the analyst first must demonstrate that
the requirements of Section 8.2 can be met using the methods as revised
to incorporate the cleanup procedure.
11.2 Before the silica gel cleanup technique can be utilized, the
extract solvent must be exchanged to cyclohexane. Add 1 to 10 mL of the
sample extract (in methylene chloride) and a boiling chip to a clean K-D
concentrator tube. Add 4 mL of cyclohexane and attach a two-ball micro-
Snyder column. Prewet the column by adding 0.5 mL of methylene chloride
to the top. Place the micro-K-D apparatus on a boiling (100 [deg]C)
water bath so that the concentrator tube is partially immersed in the
hot water. Adjust the vertical position of the apparatus and the water
temperature as required to complete concentration in 5 to 10 min. At the
proper rate of distillation the balls of the column will actively
chatter but the chambers will not flood. When the apparent volume of the
liquid reaches 0.5 mL, remove the K-D apparatus and allow it to drain
and cool for at least 10 min. Remove the micro-Snyder column and rinse
its lower joint into the concentrator tube with a minimum amount of
cyclohexane. Adjust the extract volume to about 2 mL.
11.3 Silica gel column cleanup for PAHs:
11.3.1 Prepare a slurry of 10 g of activiated silica gel in
methylene chloride and place this into a 10-mm ID chromatographic
column. Tap the column to settle the silica gel and elute the methylene
chloride. Add 1 to 2 cm of anhydrous sodium sulfate to the top of the
silica gel.
11.3.2 Preelute the column with 40 mL of pentane. The rate for all
elutions should be about 2 mL/min. Discard the eluate and just prior to
exposure of the sodium sulfate layer to the air, transfer the 2-mL
cyclohexane sample extract onto the column using an additional 2 mL
cyclohexane to complete the transfer. Just prior to exposure of the
sodium sulfate layer to the air, add 25 mL of pentane and continue the
elution of the column. Discard this pentane eluate.
11.3.3 Next, elute the column with 25 mL of methylene chloride/
pentane (4 + 6)(V/V) into a 500-mL K-D flask equipped with a 10-mL
concentrator tube. Concentrate the collected fraction to less than 10 mL
as in Section 10.6. When the apparatus is cool, remove the Snyder column
and rinse the flask and its lower joint with pentane. Proceed with HPLC
or GC analysis.
12. High Performance Liquid Chromatography
12.1 To the extract in the concentrator tube, add 4 mL of
acetonitrile and a new boiling chip, then attach a two-ball micro-Snyder
column. Concentrate the solvent as in Section 10.6, except set the water
bath at 95 to 100 [deg]C. When the apparatus is cool, remove the micro-
Snyder column and rinse its lower joint into the concentrator tube with
about 0.2 mL of acetonitrile. Adjust the extract volume to 1.0 mL.
12.2 Table 1 summarizes the recommended operating conditions for the
HPLC. Included in this table are retention times, capacity factors, and
MDL that can be achieved under these conditions. The UV detector is
recommended for the determination of naphthalene, acenaphthylene,
acenapthene, and
[[Page 210]]
fluorene and the fluorescence detector is recommended for the remaining
PAHs. Examples of the separations achieved by this HPLC column are shown
in Figures 1 and 2. Other HPLC columns, chromatographic conditions, or
detectors may be used if the requirements of Section 8.2 are met.
12.3 Calibrate the system daily as described in Section 7.
12.4 If the internal standard calibration procedure is being used,
the internal standard must be added to the sample extract and mixed
thoroughly immediately before injection into the instrument.
12.5 Inject 5 to 25 [micro]L of the sample extract or standard into
the HPLC using a high pressure syringe or a constant volume sample
injection loop. Record the volume injected to the nearest 0.1 [micro]L,
and the resulting peak size in area or peak height units. Re-equilibrate
the HPLC column at the initial gradient conditions for at least 10 min
between injections.
12.6 Identify the parameters in the sample by comparing the
retention time of the peaks in the sample chromatogram with those of the
peaks in standard chromatograms. The width of the retention time window
used to make identifications should be based upon measurements of actual
retention time variations of standards over the course of a day. Three
times the standard deviation of a retention time for a compound can be
used to calculate a suggested window size; however, the experience of
the analyst should weigh heavily in the interpretation of chromatograms.
12.7 If the response for a peak exceeds the working range of the
system, dilute the extract with acetonitrile and reanalyze.
12.8 If the measurement of the peak response is prevented by the
presence of interferences, further cleanup is required.
13. Gas Chromatography
13.1 The packed column GC procedure will not resolve certain
isomeric pairs as indicated in Section 1.3 and Table 2. The liquid
chromatographic procedure (Section 12) must be used for these
parameters.
13.2 To achieve maximum sensitivity with this method, the extract
must be concentrated to 1.0 mL. Add a clean boiling chip to the
methylene chloride extract in the concentrator tube. Attach a two-ball
micro-Snyder column. Prewet the micro-Snyder column by adding about 0.5
mL of methylene chloride to the top. Place the micro-K-D apparatus on a
hot water bath (60 to 65 [deg]C) so that the concentrator tube is
partially immersed in the hot water. Adjust the vertical position of the
apparatus and the water temperature as required to complete the
concentration in 5 to 10 min. At the proper rate of distillation the
balls will actively chatter but the chambers will not flood. When the
apparent volume of liquid reaches 0.5 mL, remove the K-D apparatus and
allow it to drain and cool for at least 10 min. Remove the micro-Snyder
column and rinse its lower joint into the concentrator tube with a
minimum amount of methylene chloride. Adjust the final volume to 1.0 mL
and stopper the concentrator tube.
13.3 Table 2 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are retention times that were
obtained under these conditions. An example of the separations achieved
by this column is shown in Figure 3. Other packed or capillary (open-
tubular) columns, chromatographic conditions, or detectors may be used
if the requirements of Section 8.2 are met.
13.4 Calibrate the gas chromatographic system daily as described in
Section 7.
13.5 If the internal standard calibration procedure is being used,
the internal standard must be added to the sample extract and mixed
thoroughly immediately before injection into the gas chromatograph.
13.6 Inject 2 to 5 [micro]L of the sample extract or standard into
the gas chromatograph using the solvent-flush technique. \10\ Smaller
(1.0 [micro]L) volumes may be injected if automatic devices are
employed. Record the volume injected to the nearest 0.05 [micro]L, and
the resulting peak size in area or peak height units.
13.7 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
13.8 If the response for a peak exceeds the working range of the
system, dilute the extract and reanalyze.
13.9 If the measurement of the peak response is prevented by the
presence of interferences, further cleanup is required.
14. Calculations
14.1 Determine the concentration of individual compounds in the
sample.
14.1.1 If the external standard calibration procedure is used,
calculate the amount of material injected from the peak response using
the calibration curve or calibration factor determined in Section 7.2.2.
The concentration in the sample can be calculated from Equation 2.
[[Page 211]]
[GRAPHIC] [TIFF OMITTED] TC15NO91.114
Equation 2
where:
A = Amount of material injected (ng).
Vi = Volume of extract injected ([micro]L).
Vt = Volume of total extract ([micro]L).
Vs = Volume of water extracted (mL).
13.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.115
Equation 3
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Is = Amount of internal standard added to each extract
([micro]g).
Vo = Volume of water extracted (L).
14.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
15. Method Performance
15.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentrations
listed in Table 1 were obtained using reagent water. \11\ Similar
results were achieved using representative wastewaters. MDL for the GC
approach were not determined. The MDL actually achieved in a given
analysis will vary depending on instrument sensitivity and matrix
effects.
15.2 This method has been tested for linearity of spike recovery
from reagent water and has been demonstrated to be applicable over the
concentration range from 8 x MDL to 800 x MDL \11\ with the following
exception: benzo(ghi)perylene recovery at 80 x and 800 x MDL were low
(35% and 45%, respectively).
15.3 This method was tested by 16 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
at six concentrations over the range 0.1 to 425 [micro]g/L. \12\ Single
operator precision, overall precision, and method accuracy were found to
be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 4.
References
1. 40 CFR part 136, appendix B.
2. ``Determination of Polynuclear Aromatic Hydrocarbons in
Industrial and Municipal Wastewaters,'' EPA 600/4-82-025, National
Technical Information Service, PB82-258799, Springfield, Virginia 22161,
June 1982.
3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard
Practices for Preparation of Sample Containers and for Preservation of
Organic Constituents,'' American Society for Testing and Materials,
Philadelphia.
4. ``Carcinogens--Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
6. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value 1.22
derived in this report.)
8. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard
Practices for Sampling Water,'' American Society for Testing and
Materials, Philadelphia.
9. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268, March 1979.
10. Burke, J.A. ``Gas Chromatography for Pesticide Residue Analysis;
Some Practical Aspects,'' Journal of the Association of Official
Analytical Chemists, 48, 1037 (1965).
11. Cole, T., Riggin, R., and Glaser, J. ``Evaluation of Method
Detection Limits and Analytical Curve for EPA Method 610--PNAs,''
International Symposium on Polynuclear Aromatic Hydrocarbons, 5th,
Battelle's Columbus Laboratories, Columbus, Ohio (1980).
12. ``EPA Method Study 20, Method 610 (PNA's),'' EPA 600/4-84-063,
National Technical Information Service, PB84-211614, Springfield,
Virginia 22161, June 1984.
[[Page 212]]
Table 1--High Performance Liquid Chromatography Conditions and Method
Detection Limits
------------------------------------------------------------------------
Method
Retention Column detection
Parameter time capacity limit
(min) factor ([micro]g/
(k') L) \a\
------------------------------------------------------------------------
Naphthalene........................... 16.6 12.2 1.8
Acenaphthylene........................ 18.5 13.7 2.3
Acenaphthene.......................... 20.5 15.2 1.8
Fluorene.............................. 21.2 15.8 0.21
Phenanthrene.......................... 22.1 16.6 0.64
Anthracene............................ 23.4 17.6 0.66
Fluoranthene.......................... 24.5 18.5 0.21
Pyrene................................ 25.4 19.1 0.27
Benzo(a)anthracene.................... 28.5 21.6 0.013
Chrysene.............................. 29.3 22.2 0.15
Benzo(b)fluoranthene.................. 31.6 24.0 0.018
Benzo(k)fluoranthene.................. 32.9 25.1 0.017
Benzo(a)pyrene........................ 33.9 25.9 0.023
Dibenzo(a,h)anthracene................ 35.7 27.4 0.030
Benzo(ghi)perylene.................... 36.3 27.8 0.076
Indeno(1,2,3-cd)pyrene................ 37.4 28.7 0.043
------------------------------------------------------------------------
HPLC column conditions: Reverse phase HC-ODS Sil-X, 5 micron particle
size, in a 25 cm x 2.6 mm ID stainless steel column. Isocratic elution
for 5 min. using acetonitrile/water (4 + 6), then linear gradient
elution to 100% acetonitrile over 25 min. at 0.5 mL/min flow rate. If
columns having other internal diameters are used, the flow rate should
be adjusted to maintain a linear velocity of 2 mm/sec.
\a\ The MDL for naphthalene, acenaphthylene, acenaphthene, and fluorene
were determined using a UV detector. All others were determined using
a fluorescence detector.
Table 2--Gas Chromatographic Conditions and Retention Times
------------------------------------------------------------------------
Retention
Parameter time (min)
------------------------------------------------------------------------
Naphthalene................................................. 4.5
Acenaphthylene.............................................. 10.4
Acenaphthene................................................ 10.8
Fluorene.................................................... 12.6
Phenanthrene................................................ 15.9
Anthracene.................................................. 15.9
Fluoranthene................................................ 19.8
Pyrene...................................................... 20.6
Benzo(a)anthracene.......................................... 24.7
Chrysene.................................................... 24.7
Benzo(b)fluoranthene........................................ 28.0
Benzo(k)fluoranthene........................................ 28.0
Benzo(a)pyrene.............................................. 29.4
Dibenzo(a,h)anthracene...................................... 36.2
Indeno(1,2,3-cd)pyrene...................................... 36.2
Benzo(ghi)perylene.......................................... 38.6
------------------------------------------------------------------------
GC Column conditions: Chromosorb W-AW-DCMS (100/120 mesh) coated with 3%
OV-17 packed in a 1.8 x 2 mm ID glass column with nitrogen carrier gas
at 40 mL/min. flow rate. Column temperature was held at 100 [deg]C for
4 min., then programmed at 8 [deg]C/min. to a final hold at 280
[deg]C.
Table 3--QC Acceptance Criteria--Method 610
----------------------------------------------------------------------------------------------------------------
Test conc. Limit for s Range for X
Parameter ([micro]g/ ([micro]g/ ([micro]g/ Range for
L) L) L) P, Ps (%)
----------------------------------------------------------------------------------------------------------------
Acenaphthene................................................ 100 40.3 D-105.7 D-124
Acenaphthylene.............................................. 100 45.1 22.1-112.1 D-139
Anthracene.................................................. 100 28.7 11.2-112.3 D-126
Benzo(a)anthracene.......................................... 10 4.0 3.1-11.6 12-135
Benzo(a)pyrene.............................................. 10 4.0 0.2-11.0 D-128
Benzo(b)fluor-anthene....................................... 10 3.1 1.8-13.8 6-150
Benzo(ghi)perylene.......................................... 10 2.3 D-10.7 D-116
Benzo(k)fluo-ranthene....................................... 5 2.5 D-7.0 D-159
Chrysene.................................................... 10 4.2 D-17.5 D-199
Dibenzo(a,h)an-thracene..................................... 10 2.0 0.3-10.0 D-110
Fluoranthene................................................ 10 3.0 2.7-11.1 14-123
Fluorene.................................................... 100 43.0 D-119 D-142
Indeno(1,2,3-cd)pyrene...................................... 10 3.0 1.2-10.0 D-116
Naphthalene................................................. 100 40.7 21.5-100.0 D-122
Phenanthrene................................................ 100 37.7 8.4-133.7 D-155
Pyrene...................................................... 10 3.4 1.4-12.1 D-140
----------------------------------------------------------------------------------------------------------------
s = Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X = Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps = Percent recovery measured (Section 8.3.2, Section 8.4.2).
D = Detected; result must be greater than zero.
Note: These criteria are based directly upon the method performance data in Table 4. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 4.
[[Page 213]]
Table 4--Method Accuracy and Precision as Functions of Concentration--Method 610
----------------------------------------------------------------------------------------------------------------
Accuracy, as Single analyst Overall
Parameter recovery, X' precision, sr' precision, S'
([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
Acenaphthene.................................................... 0.52C + 0.54 0.39X + 0.76 0.53X + 1.32
Acenaphthylene.................................................. 0.69C - 1.89 0.36X + 0.29 0.42X + 0.52
Anthracene...................................................... 0.63C - 1.26 0.23X + 1.16 0.41X + 0.45
Benzo(a)anthracene.............................................. 0.73C + 0.05 0.28X + 0.04 0.34X + 0.02
Benzo(a)pyrene.................................................. 0.56C + 0.01 0.38X - 0.01 0.53X - 0.01
Benzo(b)fluoranthene............................................ 0.78C + 0.01 0.21X + 0.01 0.38X - 0.00
Benzo(ghi)perylene.............................................. 0.44C + 0.30 0.25X + 0.04 0.58X + 0.10
Benzo(k)fluoranthene............................................ 0.59C + 0.00 0.44X - 0.00 0.69X + 0.01
Chrysene........................................................ 0.77C - 0.18 0.32X - 0.18 0.66X - 0.22
Dibenzo(a,h)anthracene.......................................... 0.41C + 0.11 0.24X + 0.02 0.45X + 0.03
Fluoranthene.................................................... 0.68C + 0.07 0.22X + 0.06 0.32X + 0.03
Fluorene........................................................ 0.56C - 0.52 0.44X - 1.12 0.63X - 0.65
Indeno(1,2,3-cd)pyrene.......................................... 0.54C + 0.06 0.29X + 0.02 0.42X + 0.01
Naphthalene..................................................... 0.57C - 0.70 0.39X - 0.18 0.41X + 0.74
Phenanthrene.................................................... 0.72C - 0.95 0.29X + 0.05 0.47X - 0.25
Pyrene.......................................................... 0.69C - 0.12 0.25X + 0.14 0.42X - 0.00
----------------------------------------------------------------------------------------------------------------
X' = Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/L.
sr' = Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S' = Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C = True value for the concentration, in [micro]g/L.
X = Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
[GRAPHIC] [TIFF OMITTED] TC02JY92.031
[[Page 214]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.032
[[Page 215]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.033
Method 611--Haloethers
1. Scope and Application
1.1 This method covers the determination of certain haloethers. The
following parameters can be determined by this method:
------------------------------------------------------------------------
Parameter STORET No. CAS No.
------------------------------------------------------------------------
Bis(2-chloroethyl) ether................ 34273 111-44-4
Bis(2-chloroethoxy) methane............. 34278 111-91-1
2, 2[min]-oxybis (1-chloropropane)...... 34283 108-60-1
4-Bromophenyl phenyl ether.............. 34636 101-55-3
4-Chlorophenyl phenyl ether............. 34641 7005-72-3
------------------------------------------------------------------------
1.2 This is a gas chromatographic (GC) method applicable to the
determination of the compounds listed above in municipal and industrial
discharges as provided under 40 CFR 136.1. When this method is used to
analyze unfamiliar samples for any or all of the compounds above,
compound identifications should be supported by at least one additional
qualitative technique. This method describes analytical conditions for a
second gas chromatographic column that can be used to confirm
measurements made with the primary column. Method 625 provides gas
chromatograph/mass spectrometer (GC/MS) conditions appropriate for the
qualitative and quantitative confirmation of results for all of the
parameters listed above, using the extract produced by this method.
[[Page 216]]
1.3 The method detection limit (MDL, defined in Section 14.1) \1\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
1.4 The sample extraction and concentration steps in this method are
essentially the same as in Methods 606, 608, 609, and 612. Thus, a
single sample may be extracted to measure the parameters included in the
scope of each of these methods. When cleanup is required, the
concentration levels must be high enough to permit selecting aliquots,
as necessary, to apply appropriate cleanup procedures. The analyst is
allowed the latitude, under Section 12, to select chromatographic
conditions appropriate for the simultaneous measurement of combinations
of these parameters.
1.5 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.6 This method is restricted to use by or under the supervision of
analysts experienced in the use of a gas chromatograph and in the
interpretation of gas chromatograms. Each analyst must demonstrate the
ability to generate acceptable results with this method using the
procedure described in Section 8.2.
2. Summary of Method
2.1 A measured volume of sample, approximately 1-L, is extracted
with methylene chloride using a separatory funnel. The methylene
chloride extract is dried and exchanged to hexane during concentration
to a volume of 10 mL or less. The extract is separated by gas
chromatography and the parameters are then measured with a halide
specific detector. \2\
2.2 The method provides a Florisil column cleanup procedure to aid
in the elimination of interferences that may be encountered.
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardware that lead to
discrete artifacts and/or elevated baselines in gas chromatograms. All
of these materials must be routinely demonstrated to be free from
interferences under the conditions of the analysis by running laboratory
reagent blanks as described in Section 8.1.3.
3.1.1 Glassware must be scrupulously cleaned. \3\ Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed be detergent washing with
hot water, and rinses with tap water and distilled water. The glassware
should then be drained dry, and heated in a muffle furnace at 400 [deg]C
for 15 to 30 min. Some thermally stable materials, such a PCBs, may not
be eliminated by this treatment. Solvent rinses with acetone and
pesticide quality hexane may be substituted for the muffle furnace
heating. Thorough rinsing with such solvents usually eliminates PCB
interference. Volumetric ware should not be heated in a muffle furnace.
After drying and cooling, glassware should be sealed and stored in a
clean environment to prevent any accumulation of dust or other
contaminants. Store inverted or capped with aluminum foil.
3.1.2 The use of high purity reagents and solvents helps to minimize
interference problems. Purification of solvents by distillation in all-
glass systems may be required.
3.2 Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary
considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled. The
cleanup procedure in Section 11 can be used to overcome many of these
interferences, but unique samples may require additional cleanup
approaches to achieve the MDL listed in Table 1.
3.3 Dichlorobenzenes are known to coelute with haloethers under some
gas chromatographic conditions. If these materials are present together
in a sample, it may be necessary to analyze the extract with two
different column packings to completely resolve all of the compounds.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified \4-6\ for
the information of the analyst.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--1-L or 1-qt, amber glass, fitted with a
screw cap lined with Teflon. Foil may be substituted for Teflon if the
sample is not corrosive. If amber bottles are not available, protect
samples from light. The bottle and cap liner must be washed, rinsed with
acetone or methylene
[[Page 217]]
chloride, and dried before use to minimize contamination.
5.1.2 Automatic sampler (optional)--The sampler must incorporate
glass sample containers for the collection of a minimum of 250 mL of
sample. Sample containers must be kept refrigerated at 4 [deg]C and
protected from light during compositing. If the sampler uses a
peristaltic pump, a minimum length of compressible silicone rubber
tubing may be used. Before use, however, the compressible tubing should
be thoroughly rinsed with methanol, followed by repeated rinsings with
distilled water to minimize the potential for contamination of the
sample. An integrating flow meter is required to collect flow
proportional composites.
5.2 Glassware (All specifications are suggested. Catalog numbers are
included for illustration only.):
5.2.1 Separatory funnel--2-L, with Teflon stopcock.
5.2.2 Drying column--Chromatographic column, approximately 400 mm
long x 19 mm ID, with coarse frit filter disc.
5.2.3 Chromatographic column--400 mm long x 19 mm ID, with Teflon
stopcock and coarse frit filter disc at bottom (Kontes K-420540-0224 or
equivalent).
5.2.4 Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes K-
570050-1025 or equivalent). Calibration must be checked at the volumes
employed in the test. Ground glass stopper is used to prevent
evaporation of extracts.
5.2.5 Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
5.2.6 Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
5.2.7 Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
5.3 Boiling chips--Approximately 10/40 mesh. Heat to 400 [deg]C for
30 min or Soxhlet extract with methylene chloride.
5.4 Water bath--Heated, with concentric ring cover, capable of
temperature control (2 [deg]C). The bath should be
used in a hood.
5.5 Balance--Analytical, capable of accurately weighing 0.0001 g.
5.6 Gas chromatograph--An analytical system complete with
temperature programmable gas chromatograph suitable for on-column
injection and all required accessories including syringes, analytical
columns, gases, detector, and strip-chart recorder. A data system is
recommended for measuring peak areas.
5.6.1 Column 1--1.8 m long x 2 mm ID glass, packed with 3% SP-1000
on Supelcoport (100/120 mesh) or equivalent. This column was used to
develop the method performance statements in Section 14. Guidelines for
the use of alternate column packings are provided in Section 12.1.
5.6.2 Column 2--1.8 m long x 2 mm ID glass, packed with 2,6-
diphenylene oxide polymer (60/80 mesh), Tenax, or equivalent.
5.6.3 Detector--Halide specific detector: electrolytic conductivity
or microcoulometric. These detectors have proven effective in the
analysis of wastewaters for the parameters listed in the scope (Section
1.1). The Hall conductivity detector was used to develop the method
performance statements in Section 14. Guidelines for the use of
alternate detectors are provided in Section 12.1. Although less
selective, an electron capture detector is an acceptable alternative.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.2 Sodium thiosulfate--(ACS) Granular.
6.3 Acetone, hexane, methanol, methylene chloride, petroleum ether
(boiling range 30-60 [deg]C)--Pesticide quality or equivalent.
6.4 Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at
400 [deg]C for 4 h in a shallow tray.
6.5 Florisil--PR Grade (60/100 mesh). Purchase activated at 1250
[deg]F and store in the dark in glass containers with ground glass
stoppers or foil-lined screw caps. Before use, activate each batch at
least 16 h at 130 [deg]C in a foil-covered glass container and allow to
cool.
6.6 Ethyl ether--Nanograde, redistilled in glass if necessary.
6.6.1 Ethyl ether must be shown to be free of peroxides before it is
used as indicated by EM Laboratories Quant test strips. (Available from
Scientific Products Co., Cat. No. P1126-8, and other suppliers.)
6.6.2 Procedures recommended for removal of peroxides are provided
with the test strips. After cleanup, 20 mL of ethyl alcohol preservative
must be added to each liter of ether.
6.7 Stock standard solutions (1.00 [micro]g/[micro]L)--Stock
standard solutions can be prepared from pure standard materials or
purchased as certified solutions.
6.7.1 Prepare stock standard solutions by accurately weighing about
0.0100 g of pure material. Dissolve the material in acetone and dilute
to volume in a 10-mL volumetric flask. Larger volumes can be used at the
convenience of the analyst. When compound purity is assayed to be 96% or
greater, the weight can be used without correction to calculate the
concentration of the stock standard. Commercially prepared stock
standards can be used at any concentration if they are certified by the
manufacturer or by an independent source.
6.7.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles. Store at 4 [deg]C and protect from light. Stock
[[Page 218]]
standard solutions should be checked frequently for signs of degradation
or evaporation, especially just prior to preparing calibration standards
from them.
6.7.3 Stock standard solutions must be replaced after six months, or
sooner if comparison with check standards indicates a problem.
6.8 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Establish gas chromatographic operating conditions equivalent to
those given in Table 1. The gas chromatographic system can be calibrated
using the external standard technique (Section 7.2) or the internal
standard technique (Section 7.3).
7.2 External standard calibration procedure:
7.2.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask and diluting to volume
with hexane. One of the external standards should be at a concentration
near, but above, the MDL (Table 1) and the other concentrations should
correspond to the expected range of concentrations found in real samples
or should define the working range of the detector.
7.2.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against the mass injected. The results can be used to prepare
a calibration curve for each compound. Alternatively, if the ratio of
response to amount injected (calibration factor) is a constant over the
working range (<10% relative standard deviation, RSD), linearity through
the origin can be assumed and the average ratio or calibration factor
can be used in place of a calibration curve.
7.3 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the compounds of interest. The analyst must
further demonstrate that the measurement of the internal standard is not
affected by method or matrix interferences. Because of these
limitations, no internal standard can be suggested that is applicable to
all samples.
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask. To each calibration
standard, add a known constant amount of one or more internal standards,
and dilute to volume with hexane. One of the standards should be at a
concentration near, but above, the MDL and the other concentrations
should correspond to the expected range of concentrations found in real
samples or should define the working range of the detector.
7.3.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against concentration for each compound and internal standard.
Calculate response factors (RF) for each compound using Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.116
Equation 1
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Cis = Concentration of the internal standard ([micro]g/L).
Cs = Concentration of the parameter to be measured ([micro]g/
L).
If the RF value over the working range is a constant (<10% RSD), the RF
can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.4 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of one or more
calibration standards. If the response for any parameter varies from the
predicted response by more than 15%, a new
calibration curve must be prepared for that compound.
7.5 The cleanup procedure in Section 11 utilizes Florisil column
chromatography. Florisil from different batches or sources may vary in
adsorptive capacity. To standardize the amount of Florisil which is
used, the use of lauric acid value \7\ is suggested. The referenced
procedure determines the adsorption from hexane solution of lauric acid
(mg) per g of Florisil. The amount of Florisil to be used for each
column is calculated by dividing 110 by this ratio and multiplying by 20
g.
7.6 Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the reagents.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality
[[Page 219]]
checks are compared with established performance criteria to determine
if the results of analyses meet the performance characteristics of the
method. When results of sample spikes indicate atypical method
performance, a quality control check standard must be analyzed to
confirm that the measurements were performed in an in-control mode of
operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Sections 10.4, 11.1, and 12.1) to improve the separations or lower the
cost of measurements. Each time such a modification is made to the
method, the analyst is required to repeat the procedure in Section 8.2.
8.1.3 Before processing any samples, the analyst must analyze a
reagent water blank to demonstrate that interferences from the
analytical system and glassware are under control. Each time a set of
samples is extracted or reagents are changed, a reagent water blank must
be processed as a safeguard against laboratory contamination.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing each parameter of interest at a concentration of 100
[micro]g/mL in acetone. The QC check sample concentrate must be obtained
from the U.S. Environmental Protection Agency, Environmental Monitoring
and Support Laboratory in Cincinnati, Ohio, if available. If not
available from that source, the QC check sample concentrate must be
obtained from another external source. If not available from either
source above, the QC check sample concentrate must be prepared by the
laboratory using stock standards prepared independently from those used
for calibration.
8.2.2 Using a pipet, prepare QC check samples at a concentration of
100 [micro]g/L by adding 1.00 mL of QC check sample concentrate to each
of four 1-L aliquots of reagent water.
8.2.3 Analyze the well-mixed QC check samples according to the
method beginning in Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 2. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If any individual s exceeds the precision limit or
any individual X falls outside the range for accuracy, the system
performance is unacceptable for that parameter. Locate and correct the
source of the problem and repeat the test for all parameters of interest
beginning with Section 8.2.2.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1. The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at 100 [micro]g/L or 1 to 5 times higher than the
background concentration determined in Section 8.3.2, whichever
concentration would be larger.
8.3.1.3 If it is impractical to determine background levels before
spiking (e.g., maximum holding times will be exceeded), the spike
concentration should be (1) the regulatory concentration limit, if any;
or, if none (2) the larger of either 5 times higher than the expected
background concentration or 100 [micro]g/L.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second sample aliquot with 1.0 mL
of the QC check sample concentrate and analyze it to determine the
concentration after spiking (A) of each parameter. Calculate each
percent recovery (P)
[[Page 220]]
as 100(A-B)%/T, where T is the known true value of the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 2. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\8\ If spiking was performed at a concentration lower than 100 [micro]g/
L, the analyst must use either the QC acceptance criteria in Table 2, or
optional QC acceptance criteria calculated for the specific spike
concentration. To calculate optional acceptance criteria for the
recovery of a parameter: (1) Calculate accuracy (X') using the equation
in Table 3, substituting the spike concentration (T) for C; (2)
calculate overall precision (S') using the equation in Table 3,
substituting X' for X; (3) calculate the range for recovery at the spike
concentration as (100 X'/T)2.44(100 S'/T)%. \8\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory.
8.4.1 Prepare the QC check standard by adding 1.0 m/L of QC check
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The
QC check standard needs only to contain the parameters that failed
criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
2. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P092sp to P +
2sp. If P = 90% and sp = 10%, for example, the
accuracy interval is expressed as 70-110%. Update the accuracy
assessment for each parameter on a regular basis (e.g. after each five
to ten new accuracy measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as gas chromatography with a dissimilar column, specific element
detector, or mass spectrometer must be used. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevant performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices \9\ should be followed, except that the bottle must
not be prerinsed with sample before collection. Composite samples should
be collected in refrigerated glass containers in accordance with the
requirements of the program. Automatic sampling equipment must be as
free as possible of Tygon tubing and other potential sources of
contamination.
9.2 All samples must be iced or refrigerated at 4 [deg]C from the
time of collection until extraction. Fill the sample bottles and, if
residual chlorine is present, add 80 mg of sodium thiosulfate per liter
of sample and mix well. EPA Methods 330.4 and 330.5 may be used for
measurement of residual chlorine. \10\ Field test kits are available for
this purpose.
9.3 All samples must be extracted within 7 days of collection and
completely analyzed within 40 days of extraction. \2\
10. Sample Extraction
10.1 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Pour the entire sample into a 2-L
separatory funnel.
10.2 Add 60 mL methylene chloride to the sample bottle, seal, and
shake 30 s to rinse the inner surface. Transfer the solvent to the
separatory funnel and extract the sample by shaking the funnel for 2 min
with periodic
[[Page 221]]
venting to release excess pressure. Allow the organic layer to separate
from the water phase for a minimum of 10 min. If the emulsion interface
between layers is more than one-third the volume of the solvent layer,
the analyst must employ mechanical techniques to complete the phase
separation. The optimum technique depends upon the sample, but may
include stirring, filtration of the emulsion through glass wool,
centrifugation, or other physical methods. Collect the methylene
chloride extract in a 250-mL Erlenmeyer flask.
10.3 Add a second 60-mL volume of methylene chloride to the sample
bottle and repeat the extraction procedure a second time, combining the
extracts in the Erlenmeyer flask. Perform a third extraction in the same
manner.
10.4 Assemble a Kuderna-Danish (K-D) concentrator by attaching a 10-
mL concentrator tube to a 500-mL evaporative flask. Other concentration
devices or techniques may be used in place of the K-D concentrator if
the requirements of Section 8.2 are met.
10.5 Pour the combined extract through a solvent-rinsed drying
column containing about 10 cm of anhydrous sodium sulfate, and collect
the extract in the K-D concentrator. Rinse the Erlenmeyer flask and
column with 20 to 30 mL of methylene chloride to complete the
quantitative transfer.
10.6 Add one or two clean boiling chips to the evaporative flask and
attach a three-ball Snyder column. Prewet the Snyder column by adding
about 1 mL of methylene chloride to the top. Place the K-D apparatus on
a hot water bath (60 to 65 [deg]C) so that the concentrator tube is
partially immersed in the hot water, and the entire lower rounded
surface of the flask is bathed with hot vapor. Adjust the vertical
position of the apparatus and the water temperature as required to
complete the concentration in 15 to 20 min. At the proper rate of
distillation the balls of the column will actively chatter but the
chambers will not flood with condensed solvent. When the apparent volume
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain
and cool for at least 10 min.
Note: Some of the haloethers are very volatile and significant
losses will occur in concentration steps if care is not exercised. It is
important to maintain a constant gentle evaporation rate and not to
allow the liquid volume to fall below 1 to 2 mL before removing the K-D
apparatus from the hot water bath.
10.7 Momentarily remove the Snyder column, add 50 mL of hexane and a
new boiling chip, and reattach the Snyder column. Raise the temperature
of the water bath to 85 to 90 [deg]C. Concentrate the extract as in
Section 10.6, except use hexane to prewet the column. The elapsed time
of concentration should be 5 to 10 min.
10.8 Remove the Snyder column and rinse the flask and its lower
joint into the concentrator tube with 1 to 2 mL of hexane. A 5-mL
syringe is recommended for this operation. Stopper the concentrator tube
and store refrigerated if further processing will not be performed
immediately. If the extract will be stored longer than two days, it
should be transferred to a Teflon-sealed screw-cap vial. If the sample
extract requires no further cleanup, proceed with gas chromatographic
analysis (Section 12). If the sample requires further cleanup, proceed
to Section 11.
10.9 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to a 1000-mL graduated
cylinder. Record the sample volume to the nearest 5 mL.
11. Cleanup and Separation
11.1 Cleanup procedures may not be necessary for a relatively clean
sample matrix. If particular circumstances demand the use of a cleanup
procedure, the analyst may use the procedure below or any other
appropriate procedure. However, the analyst first must demonstrate that
the requirements of Section 8.2 can be met using the method as revised
to incorporate the cleanup procedure.
11.2 Florisil column cleanup for haloethers:
11.2.1 Adjust the sample extract volume to 10 mL.
11.2.2 Place a weight of Florisil (nominally 20 g) predetermined by
calibration (Section 7.5), into a chromatographic column. Tap the column
to settle the Florisil and add 1 to 2 cm of anhydrous sodium sulfate to
the top.
11.2.3 Preelute the column with 50 to 60 mL of petroleum ether.
Discard the eluate and just prior to exposure of the sodium sulfate
layer to the air, quantitatively transfer the sample extract onto the
column by decantation and subsequent petroleum ether washings. Discard
the eluate. Just prior to exposure of the sodium sulfate layer to the
air, begin eluting the column with 300 mL of ethyl ether/petroleum ether
(6 + 94) (V/V). Adjust the elution rate to approximately 5 mL/min and
collect the eluate in a 500-mL K-D flask equipped with a 10-mL
concentrator tube. This fraction should contain all of the haloethers.
11.2.4 Concentrate the fraction as in Section 10.6, except use
hexane to prewet the column. When the apparatus is cool, remove the
Snyder column and rinse the flask and its lower joint into the
concentrator tube with hexane. Adjust the volume of the cleaned up
extract to 10 mL with hexane and analyze by gas chromatography (Section
12).
[[Page 222]]
12. Gas Chromatography
12.1 Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are retention times and MDL
that can be achieved under these conditions. Examples of the separations
achieved by Columns 1 and 2 are shown in Figures 1 and 2, respectively.
Other packed or capillary (open-tubular) columns, chromatographic
conditions, or detectors may be used if the requirements of Section 8.2
are met.
12.2 Calibrate the system daily as described in Section 7.
12.3 If the internal standard calibration procedure is being used,
the internal standard must be added to the sample extract and mixed
thoroughly immediately before injection into the gas chromatrograph.
12.4 Inject 2 to 5 [micro]L of the sample extract or standard into
the gas chromatograph using the solvent-flush technique. \11\ Smaller
(1.0 [micro]L) volumes may be injected if automatic devices are
employed. Record the volume injected to the nearest 0.05 [micro]L, the
total extract volume, and the resulting peak size in area or peak height
units.
12.5 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weight heavily in the interpretation of
chromatograms.
12.6 If the response for a peak exceeds the working range of the
system, dilute the extract and reanalyze.
12.7 If the measurement of the peak response is prevented by the
presence of interferences, further cleanup is required.
13. Calculations
13.1 Determine the concentration of individual compounds in the
sample.
13.1.1 If the external standard calibration procedure is used,
calculate the amount of material injected from the peak response using
the calibration curve or calibration factor determined in Section 7.2.2.
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.117
Equation 2
where:
A = Amount of material injected (ng).
Vi = Volume of extract injected ([micro]L).
Vt = Volume of total extract ([micro]L).
Vs = Volume of water extracted (mL).
13.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.118
Equation 3
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Is = Amount of internal standard added to each extract
([micro]g).
Vo = Volume of water extracted (L).
13.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
14. Method Performance
14.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentrations
listed in Table 1 were obtained using reagent water. \12\ Similar
results were achieved using representative wastewaters. The MDL actually
achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
14.2 This method has been tested for linearity of spike recovery
from reagent water and has been demonstrated to be applicable over the
concentration range from 4 x MDL to 1000 x MDL. \12\
14.3 This method was tested by 20 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
at six concentrations over the range 1.0 to 626 [micro]/L. \12\ Single
operator precision, overall precision, and method accuracy were found to
be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 3.
References
1. 40 CFR part 136, appendix B.
2. ``Determination of Haloethers in Industrial and Municipal
Wastewaters,'' EPA 600/4-81-062, National Technical Information Service,
PB81-232290, Springfield, Virginia 22161, July 1981.
[[Page 223]]
3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard
Practices for Preparation of Sample Containers and for Preservation of
Organic Constitutents,'' American Society for Testing and Materials,
Philadelphia.
4. ``Carcinogens--Working Carcinogens, '' Department of Health,
Education, and Welfare, Public Health Services, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
6. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
7. Mills., P.A. ``Variation of Florisil Activity: Simple Method for
Measuring Absorbent Capacity and Its Use in Standardizing Florisil
Columns,'' Journal of the Association of Official Analytical Chemists,
51, 29 (1968).
8. Provost, L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value 1.22
derived in this report.)
9. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard
Practices for Sampling Water,'' American Society for Testing and
Materials, Philadelphia.
10. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268, March 1979.
11. Burke, J.A. ``Gas Chromatography for Pesticide Residue Analysis;
Some Practical Aspects,'' Journal of the Association of Official
Analytical Chemists, 48, 1037 (1965).
12. ``EPA Method Study 21, Method 611, Haloethers,'' EPA 600/4-84-
052, National Technical Information Service, PB84-205939, Springfield,
Virginia 22161, June 1984.
Table 1--Chromatographic Conditions and Methods Detection Limits
------------------------------------------------------------------------
Retention time (min) Method
---------------------- detection
Parameters limit
Column 1 Column 2 ([micro]/
L)
------------------------------------------------------------------------
Bis(2-chloroisopropyl) ether........... 8.4 9.7 0.8
Bis(2-chloroethyl) ether............... 9.3 9.1 0.3
Bis(2-chloroethoxy) methane............ 13.1 10.0 0.5
4-Chlorophenyl ether................... 19.4 15.0 3.9
4-Bromophenyl phenyl ether............. 21.2 16.2 2.3
------------------------------------------------------------------------
Column 1 conditions: Supelcoport (100/120 mesh) coated with 3% SP-1000
packed in a 1.8 m long x 2 mm ID glass column with helium carrier gas
at 40 mL/min. flow rate. Column temperature held at 60 [deg]C for 2
min. after injection then programmed at 8 [deg]C/min. to 230 [deg]C
and held for 4 min. Under these conditions the retention time for
Aldrin is 22.6 min.
Column 2 conditions: Tenax-GC (60/80 mesh) packed in a 1.8 m long x 2mm
ID glass column with helium carrier gas at 40 mL/min. flow rate.
Column temperature held at 150 [deg]C for 4 min. after injection then
programmed at 16 [deg]C/min. to 310 [deg]C. Under these conditions the
retention time for Aldrin is 18.4 min.
Table 2--QC Acceptance Criteria--Method 611
----------------------------------------------------------------------------------------------------------------
Test conc. Range for X Range for
Parameter ([micro]g/ Limit for s ([micro]g/ P, Ps
L) ([micro]g/L) L) percent
----------------------------------------------------------------------------------------------------------------
Bis (2-chloroethyl)ether................................... 100 26.3 26.3-136.8 11-152
Bis (2-chloroethoxy)methane................................ 100 25.7 27.3-115.0 12-128
Bis (2-chloroisopropyl)ether............................... 100 32.7 26.4-147.0 9-165
4-Bromophenyl phenyl ether................................. 100 39.3 7.6-167.5 D-189
4-Chlorophenyl phenyl ether................................ 100 30.7 15.4-152.5 D-170
----------------------------------------------------------------------------------------------------------------
s = Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X = Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps = Percent recovery measured (Section 8.3.2, Section 8.4.2).
D = Detected; result must be greater than zero.
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 3.
Table 3--Method Accuracy and Precision as Functions of Concentration--Method 611
----------------------------------------------------------------------------------------------------------------
Accuracy, as Single analyst Overall
Parameter recovery, X' precision, sr' precision, S'
([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
Bis(2-chloroethyl) ether........................................ 0.81C + 0.54 0.19X + 0.28 0.35X + 0,36
Bis(2-chloroethoxy) methane..................................... 0.71C + 0.13 0.20X + 0.15 0.33X + 0.11
Bis(2-chloroisopropyl) ether.................................... 0.85C + 1.67 0.20X + 1.05 0.36X + 0.79
4-Bromophenyl phenyl ether...................................... 0.85C + 2.55 0.25X + 0.21 0.47X + 0.37
[[Page 224]]
4-Chlorophenyl phenyl ether..................................... 0.82C + 1.97 0.18X + 2.13 0.41X + 0.55
----------------------------------------------------------------------------------------------------------------
X' = Expected recovery for one or more measuremelts of a sample containing a concentration of C, in [micro]g/L.
sr' = Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S' = Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C = True value for the concentration, in [micro]g/L.
X = Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
[GRAPHIC] [TIFF OMITTED] TC02JY92.034
[[Page 225]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.035
Method 612--Chlorinated Hydrocarbons
1. Scope and Application
1.1 This method covers the determination of certain chlorinated
hydrocarbons. The following parameters can be determined by this method:
------------------------------------------------------------------------
STORET
Parameter No. CAS No.
------------------------------------------------------------------------
2-Chloronaphthalene.............................. 34581 91-58-7
1,2-Dichlorobenzene.............................. 34536 95-50-1
1,3-Dichlorobenzene.............................. 34566 541-73-1
1,4-Dichlorobenzene.............................. 34571 106-46-7
Hexachlorobenzene................................ 39700 118-74-1
Hexachlorobutadiene.............................. 34391 87-68-3
Hexachlorocyclopentadiene........................ 34386 77-47-4
Hexachloroethane................................. 34396 67-72-1
[[Page 226]]
1,2,4-Trichlorobenzene........................... 34551 120-82-1
------------------------------------------------------------------------
1.2 This is a gas chromatographic (GC) method applicable to the
determination of the compounds listed above in municipal and industrial
discharges as provided under 40 CFR 136.1. When this method is used to
analyze unfamiliar samples for any or all of the compounds above,
compound identifications should be supported by at least one additional
qualitative technique. This method describes a second gas
chromatographic column that can be used to confirm measurements made
with the primary column. Method 625 provides gas chromatograph/mass
spectrometer (GC/MS) conditions appropriate for the qualitative and
quantitative confirmation of results for all of the parameters listed
above, using the extract produced by this method.
1.3 The method detection limit (MDL, defined in Section 14.1) \1\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
1.4 The sample extraction and concentration steps in this method are
essentially the same as in Methods 606, 608, 609, and 611. Thus, a
single sample may be extracted to measure the parameters included in the
scope of each of these methods. When cleanup is required, the
concentration levels must be high enough to permit selecting aliquots,
as necessary, to apply appropriate cleanup procedures. The analyst is
allowed the latitude, under Section 12, to select chromatographic
conditions appropriate for the simultaneous measurement of combinations
of these parameters.
1.5 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.6 This method is restricted to use by or under the supervision of
analysts experienced in the use of a gas chromatograph and in the
interpretation of gas chromatograms. Each analyst must demonstrate the
ability to generate acceptable results with this method using the
procedure described in Section 8.2.
2. Summary of Method
2.1 A measured volume of sample, approximately 1-L, is extracted
with methylene chloride using a separatory funnel. The methylene
chloride extract is dried and exchanged to hexane during concentration
to a volume of 10 mL or less. The extract is separated by gas
chromatography and the parameters are then measured with an electron
capture detector. \2\
2.2 The method provides a Florisil column cleanup procedure to aid
in the elimination of interferences that may be encountered.
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardware that lead to
discrete artifacts and/or elevated baselines in gas chromatograms. All
of these materials must be routinely demonstrated to be free from
interferences under the conditions of the analysis by running laboratory
reagent blanks as described in Section 8.1.3.
3.1.1 Glassware must be scrupulously cleaned. \3\ Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed by detergent washing with
hot water, and rinses with tap water and distilled water. The glassware
should then be drained dry, and heated in a muffle furnace at 400 [deg]C
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not
be eliminated by this treatment. Solvent rinses with acetone and
pesticide quality hexane may be substituted for the muffle furnace
heating. Thorough rinsing with such solvents usually eliminates PCB
interference. Volumetric ware should not be heated in a muffle furnace.
After drying and cooling, glassware should be sealed and stored in a
clean environment to prevent any accumulation of dust or other
contaminants. Store inverted or capped with aluminum foil.
3.1.2 The use of high purity reagents and solvents helps to minimize
interference problems. Purification of solvents by distillation in all-
glass systems may be required.
3.2 Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary
considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled. The
cleanup procedure in Section 11 can be used to overcome many of these
interferences, but unique samples may require additional cleanup
approaches to achieve the MDL listed in Table 1.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all
[[Page 227]]
personnel involved in the chemical analysis. Additional references to
laboratory safety are available and have been identified \4-6\ for the
information of the analyst.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--1cL or 1-qt, amber glass, fitted with a
screw cap lined with Teflon. Foil may be substituted for Teflon if the
sample is not corrosive. If amber bottles are not available, protect
samples from light. The bottle and cap liner must be washed, rinsed with
acetone or methylene chloride, and dried before use to minimize
contamination.
5.1.2 Automatic sampler (optional)--The sampler must incorporate
glass sample containers for the collection of a minimum of 250 mL of
sample. Sample containers must be kept refrigerated at 4 [deg]C and
protected from light during compositing. If the sampler uses a
peristaltic pump, a minimum length of compressible silicone rubber
tubing may be used. Before use, however, the compressible tubing should
be thoroughly rinsed with methanol, followed by repeated rinsings with
distilled water to minimize the potential for contamination of the
sample. An integrating flow meter is required to collect flow
proportional composites.
5.2 Glassware (All specifications are suggested. Catalog numbers are
included for illustration only.):
5.2.1 Separatory funnel--2-L, with Teflon stopcock.
5.2.2 Drying column--Chromatographic column, approximately 400 mm
long x 19 mm ID, with coarse frit filter disc.
5.2.3 Chromatographic column--300 long x 10 mm ID, with Teflon
stopcock and coarse frit filter disc at bottom.
5.2.4 Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes K-
570050-1025 or equivalent). Calibration must be checked at the volumes
employed in the test. Ground glass stopper is used to prevent
evaporation of extracts.
5.2.5 Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
5.2.6 Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
5.2.7 Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
5.3 Boiling chips--Approximately 10/40 mesh. Heat to 400 [deg]C for
30 min or Soxhlet extract with methylene chloride.
5.4 Water bath--Heated, with concentric ring cover, capable of
temperature control (2 [deg]C). The bath should be
used in a hood.
5.5 Balance--Analytical, capable of accurately weighing 0.0001 g.
5.6 Gas chromatograph--An analytical system complete with gas
chromatograph suitable for on-column injection and all required
accessories including syringes, analytical columns, gases, detector, and
strip-chart recorder. A data system is recommended for measuring peak
areas.
5.6.1 Column 1--1.8 m long x 2 mm ID glass, packed with 1% SP-1000
on Supelcoport (100/120 mesh) or equivalent. Guidelines for the use of
alternate column packings are provide in Section 12.1.
5.6.2 Column 2--1.8 m long x 2 mm ID glass, packed with 1.5% OV-1/
2.4% OV-225 on Supelcoport (80/100 mesh) or equivalent. This column was
used to develop the method performance statements in Section 14.
5.6.3 Detector--Electron capture detector. This detector has proven
effective in the analysis of wastewaters for the parameters listed in
the scope (Section 1.1), and was used to develop the method performance
statements in Section 14. Guidelines for the use of alternate detectors
are provided in Section 12.1.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.2 Acetone, hexane, isooctane, methanol, methylene chloride,
petroleum ether (boiling range 30 to 60 [deg]C)--Pesticide quality or
equivalent.
6.3 Sodium sulfate--(ACS) Granular, anhydrous. Purify heating at 400
[deg]C for 4 h in a shallow tray.
6.4 Florisil--PR grade (60/100 mesh). Purchase activated at 1250
[deg]F and store in the dark in glass containers with ground glass
stoppers or foil-lined screw caps. Before use, activate each batch at
least 16 h at 130 [deg]C in a foil-covered glass container and allow to
cool.
6.5 Stock standard solution (1.00 [micro]g/[micro]L)--Stock standard
solutions can be prepared from pure standard materials or purchased as
certified solutions.
6.5.1 Prepare stock standard solutions by accurately weighing about
0.0100 g of pure material. Dissolve the material in isooctane and dilute
to volume in a 120-mL volumetric flask. Larger volumes can be used at
the convenience of the analyst. When compound purity is assayed to be
96% or greater, the weight can be used without correction to calculate
the concentration of the stock standard. Commercially prepared stock
standards can be used at any concentration if they are certified by the
manufacturer or by an independent source.
6.5.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles. Store at 4 [deg]C and protect from light. Stock
standard solutions should be checked frequently for signs of degradation
or evaporation, especially just prior to preparing calibration standards
from them.
[[Page 228]]
6.5.3 Stock standard solutions must be replaced after six months, or
sooner if comparision with check standards indicates a problem.
6.6 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Establish gas chromatographic operating conditions equivalent to
those given in Table 1. The gas chromatographic system can be calibrated
using the external standard technique (Section 7.2) or the internal
standard technique (Section 7.3).
7.2 External standard calibration procedure:
7.2.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask and diluting to volume
with isooctane. One of the external standards should be at a
concentration near, but above, the MDL (Table 1) and the other
concentrations should correspond to the expected range of concentrations
found in real samples or should define the working range of the
detector.
7.2.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against the mass injected. The results can be used to prepare
a calibration curve for each compound. Alternatively, if the ratio of
response to amount injected (calibration factor) is a constant over the
working range (<10% relative standard deviation, RSD), linearity through
the origin can be assumed and the average ratio or calibration factor
can be used in place of a calibration curve.
7.3 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the compounds of interest. The analyst must
further demonstrate that the measurement of the internal standard is not
affected by method or matrix interferences. Because of these
limitations, no internal standard can be suggested that is applicable to
all samples.
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask. To each calibration
standard, add a known constant amount of one or more internal standards,
and dilute to volume with isooctane. One of the standards should be at a
concentration near, but above, the MDL and the other concentrations
should correspond to the expected range of concentrations found in real
samples or should define the working range of the detector.
7.3.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against concentration for each compound and internal standard.
Calculate response factors (RF) for each compound using Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.119
Equation 1
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Cis = Concentration of the internal standard ([micro]g/L).
Cs = Concentration of the parameter to be measured ([micro]g/
L).
If the RF value over the working range is a constant (<10% RSD), the RF
can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.4 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of one or more
calibration standards. If the response for any parameter varies from the
predicted response by more than 15%, a new
calibration curve must be prepared for that compound.
7.5 Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the reagents.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When the results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
[[Page 229]]
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Sections 10.4, 11.1, and 12.1) to improve the separations or lower the
cost of measurements. Each time such modification is made to the method,
the analyst is required to repeat the procedure in Section 8.2.
8.1.3 Before processing any samples, the analyst must analyze a
reagent water blank to demonstrate that interferences from the
analytical system and glassware are under control. Each time a set of
samples is extracted or reagents are changed, a reagent water blank must
be processed as a safeguard against laboratory contamination.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing each parameter of interest at the following concentrations in
acetone: Hexachloro-substituted parameters, 10 [micro]g/mL; any other
chlorinated hydrocarbon, 100 [micro]g/mL. The QC check sample
concentrate must be obtained from the U.S. Environmental Protection
Agency, Environmental Monitoring and Support Laboratory in Cincinnati,
Ohio, if available. If not available from that source, the QC check
sample concentrate must be obtained from another external source. If not
available from either source above, the QC check sample concentrate must
be prepared by the laboratory using stock standards prepared
independently from those used for calibration.
8.2.2 Using a pipet, prepare QC check samples at the test
concentrations shown in Table 2 by adding 1.00 mL of QC check sample
concentrate to each of four 1-L aliquots of reagent water.
8.2.3 Analyze the well-mixed QC check samples according to the
method beginning in Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 2. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If any individual s exceeds the precision limit or
any individual X falls outside the range for accuracy, the system
performance is unacceptable for that parameter.
Note: The large number of parameters in Table 2 presents a
substantial probability that one or more will fail at least one of the
acceptance criteria when all parameters are analyzed.
8.2.6 When one or more of the parameters tested fail at least one of
the acceptance criteria, the analyst must proceed according to Section
8.2.6.1 or 8.2.6.2.
8.2.6.1 Locate and correct the source of the problem and repeat the
test for all parameters of interest beginning with Section 8.2.2.
8.2.6.2 Beginning with Section 8.2.2, repeat the test only for those
parameters that failed to meet criteria. Repeated failure, however, will
confirm a general problem with the measurement system. If this occurs,
locate and correct the source of the problem and repeat the test for all
compounds of interest beginning with Section 8.2.2.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spike sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at the test concentration in Section 8.2.2 or 1 to 5
times higher than the background concentration determined in Section
8.3.2, whichever concentration would be larger.
8.3.1.3 If it is impractical to determine background levels before
spiking (e.g., maximum holding times will be exceeded), the spike
concentration should be (1) the regulatory concentration limit, if any;
or, if none by (2) the larger of either 5 times higher than the expected
background concentration or the test concentration in Section 8.2.2.
[[Page 230]]
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of each parameter. In necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second sample aliquot with 1.0 mL
of the QC check sample concentrate and analyze it to determine the
concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100 (A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 2. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\7\ If spiking was performed at a concentration lower than the test
concentration in Section 8.2.2, the analyst must use either the QC
acceptance criteria in Table 2, or optional QC acceptance criteria
calculated for the specific spike concentration. To calculate optional
acceptance criteria for the recovery of a parameter: (1) Calculate
accuracy (X') using the equation in Table 3, substituting the spike
concentration (T) for C; (2) calculate overall precision (S') using the
equation in Table 3, substituting X' for X; (3) calculate the range for
recovery at the spike concentration as (100 X'/T) 2.44 (100 S'/T)%. \7\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4. If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory.
8.4.1 Prepare the QC check standard by adding 1.0 mL of QC check
sample concentrate (Sections 8.2.1 or 8.3.2) to 1 L of reagent water.
The QC check standard needs only to contain the parameters that failed
criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
2. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2sp to P + 2sp.
If P = 90% and sp = 10%, for example, the accuracy interval
is expressed as 70-110%. Update the accuracy assessment for each
parameter on a regular basis (e.g. after each five to ten new accuracy
measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as gas chromatography with a dissimilar column, specific element
detector, or mass spectrometer must be used. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevent performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices \8\ should be followed, except that the bottle must
not be prerinsed with sample before collection. Composite samples should
be collected in refrigerated glass containers in accordance with the
requirements of the program. Automatic sampling equipment must be as
free as possible of Tygon tubing and other potential sources of
contamination.
9.2 All samples must be iced or refrigerated at 4 [deg]C from the
time of collection until extraction.
9.3 All samples must be extracted within 7 days of collection and
completely analyzed within 40 days of extraction. \2\
10. Sample Extraction
10.1 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Pour the entire sample into a 2-L
separatory funnel.
[[Page 231]]
10.2 Add 60 mL of methylele chloride to the sample bottle, seal, and
shake 30 s to rinse the inner surface. Transfer the solvent to the
separatory funnel and extract the sample by shaking the funnel for 2 min
with periodic venting to release excess pressure. Allow the organic
layer to separate from the water phase for a minimum of 10 min. If the
emulsion interface between layers is more than one-third the volume of
the solvent layer, the analyst must employ mechanical techniques to
complete the phase separation. The optimum technique depends upon the
sample, but may include stirring, filtration of the emulsion through
glass wool, centrifugation, or other physical methods. Collect the
methylene chloride extract in a 250-mL Erlenmeyer flask.
10.3 Add a second 60-mL volume of methylene chloride to the sample
bottle and repeat the extraction procedure a second time, combining the
extracts in the Erlenmeyer flask. Perform a third extraction in the same
manner.
10.4 Assemble a Kuderna-Danish (K-D) concentrator by attaching a 10-
mL concentrator tube to a 500-mL evaporative flask. Other concentration
devices or techniques may be used in place of the K-D concentrator if
the requirements of Section 8.2 are met.
10.5 Pour the combined extract through a solvent-rinsed drying
column containing about 10 cm of anhydrous sodium sulfate, and collect
the extract in the K-D concentrator. Rinse the Erlenmeyer flask and
column with 20 to 30 mL of methylene chloride to complete the
quantitative transfer.
10.6 Add one or two clean boiling chips to the evaporative flask and
attach a three-ball Snyder column. Prewet the Snyder column by adding
about 1 mL of methylene chloride to the top. Place the K-D apparatus on
a hot water bath (60 to 65 [deg]C) so that the concentrator tube is
partially immersed in the hot water, and the entire lower rounded
surface of the flask is bathed with hot vapor. Adjust the vertical
position of the apparatus and the water temperature as required to
complete the concentration in 15 to 20 min. At the proper rate of
distillation the balls of the column will actively chatter but the
chambers will not flood with condensed solvent. When the apparent volume
of liquid reaches 1 to 2 mL, remove the K-D apparatus and allow it to
drain and cool for at least 10 min.
Note: The dichloribenzenes have a sufficiently high volatility that
significant losses may occur in concentration steps if care is not
exercised. It is important to maintain a constant gentle evaporation
rate and not to allow the liquid volume to fall below 1 to 2 mL before
removing the K-D apparatus from the hot water bath.
10.7 Momentarily remove the Snyder column, add 50 mL of hexane and a
new boiling chip, and reattach the Snyder column. Raise the tempeature
of the water bath to 85 to 90 [deg]C. Concentrate the extract as in
Section 10.6, except use hexane to prewet the column. The elapsed time
of concentration should be 5 to 10 min.
10.8 Romove the Snyder column and rinse the flask and its lower
joint into the concentrator tube with 1 to 2 mL of hexane. A 5-mL
syringe is recommended for this operation. Stopper the concentrator tube
and store refrigerated if further processing will not be performed
immediately. If the extract will be stored longer than two days, it
should be transferred to a Teflon-sealed screw-cap vial. If the sample
extract requires no further cleanup, proceed with gas chromatographic
analysis (Section 12). If the sample requires further cleanup, proceed
to Section 11.
10.9 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to a 1000-mL graduated
cylinder. Record the sample volume to the nearest 5 mL.
11. Cleanup and Separation
11.1 Cleanup procedures may not be necessary for a relatively clean
sample matrix. If particular circumstances demand the use of a cleanup
procedure, the analyst may use the procedure below or any other
appropriate procedure. However, the analyst first must demonstrate that
the requirements of Section 8.2 can be met using the method as revised
to incorporate the cleanup procedure.
11.2 Florisil column cleanup for chlorinated hydrocarbons:
11.2.1 Adjust the sample extract to 10 mL with hexane.
11.2.2 Place 12 g of Florisil into a chromatographic column. Tap the
column to settle the Florisil and add 1 to 2 cm of anhydrous sodium
sulfate to the top.
11.2.3 Preelute the column with 100 mL of petroleum ether. Discard
the eluate and just prior to exposure of the sodium sulfate layer to the
air, quantitatively transfer the sample extract onto the column by
decantation and subsequent petroleum ether washings. Discard the eluate.
Just prior to exposure of the sodium sulfate layer to the air, begin
eluting the column with 200 mL of petroleum ether and collect the eluate
in a 500-mL K-D flask equipped with a 10-mL concentrator tube. This
fraction should contain all of the chlorinated hydrocarbons.
11.2.4 Concentrate the fraction as in Section 10.6, except use
hexane to prewet the column. When the apparatus is cool, remove the
Snyder column and rinse the flask and its lower joint into the
concentrator tube with hexane. Analyze by gas chromatography (Section
12).
[[Page 232]]
12. Gas Chromatography
12.1 Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are retention times and MDL
that can be achieved under these conditions. Examples of the separations
achieved by Columl 2 are shown in Figures 1 and 2. Other packed or
capillary (open-tubular) columns, chromatographic conditions, or
detectors may be used if the requirements of Section 8.2 are met.
12.2 Calibrate the system daily as described in Section 7.
12.3 If the internal standard calibration procedure is being used,
the internal standard must be added to the sample extract and mixed
throughly immediately before injection into the gas chromatograph.
12.4 Inject 2 to 5 [micro]L of the sample extract or standard into
the gas chromatograph using the solvent-flush techlique. \9\ Smaller
(1.0 [micro]L) volumes may be injected if automatic devices are
employed. Record the volume injected to the nearest 0.05 [micro]L, the
total extract volume, and the resulting peak size in area or peak height
units.
12.5 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
12.6 If the response for a peak exceeds the working range of the
system, dilute the extract and reanalyze.
12.7 If the measurement of the peak response is prevented by the
presence of interferences, further cleanup is required.
13. Calculations
13.1 Determine the concentration of individual compounds in the
sample.
13.1.1 If the external standard calibration procedure is used,
calculate the amount of material injected from the peak response using
the calibration curve or calibration factor determined in Section 7.2.2.
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.120
Equation 2
where:
A = Amount of material injected (ng).
Vi = Volume of extract injected ([micro]L).
Vt = Volume of total extract ([micro]L).
Vs = Volume of water extracted (mL).
13.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.121
Equation 3
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Is = Amount of internal standard added to each extract
([micro]g).
Vo = Volume of water extracted (L).
13.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
14. Method Performance
14.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentrations
listed in Table 1 were obtained using reagent water. \10\ Similar
results were achieved using representative wastewaters. The MDL actually
achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
14.2 This method has been tested for linearity of spike recovery
from reagent water and has been demonstrated to be applicable over the
concentration range from 4 x MDL to 1000 x MDL. \10\
14.3 This method was tested by 20 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
at six concentrations over the range 1.0 to 356 [micro]g/L. \11\ Single
operator precision, overall precision, and method accuracy were found to
be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 3.
References
1. 40 CFR part 136, appendix B.
2. ``Determination of Chlorinated Hydrocarbons In Industrial and
Municipal Wastewaters, ``EPA 6090/4-84-ABC, National Technical
Information Service, PBXYZ, Springfield, Virginia, 22161 November 1984.
3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard
Practices for Preparation of Sample Containers and for Preservation of
Organic Constituents,'' American
[[Page 233]]
Society for Testing and Materials, Philadelphia.
4. ``Carcinogens--Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
6. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,''American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value 1.22
derived in this report.)
8. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard
Practices for Sampling Water,'' American Society for Testing and
Materials, Philadelphia.
9. Burke, J.A. ``Gas Chromatography for Pesticide Residue Analysis;
Some Practical Aspects,'' Journal of the Association of Official
Analytical Chemists, 48, 1037 (1965).
10. ``Development of Detection Limits, EPA Method 612, Chlorinated
Hydrocarbons,'' Special letter report for EPA Contract 68-03-2625, U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268.
11. ``EPA Method Study Method 612--Chlorinated Hydrocarbons,'' EPA
600/4-84-039, National Technical Information Service, PB84-187772,
Springfield, Virginia 22161, May 1984.
12. ``Method Performance for Hexachlorocyclopentadiene by Method
612,'' Memorandum from R. Slater, U.S. Environmental Protection Agency,
Environmental Monitoring and Support Laboratory, Cincinnati, Ohio 45268,
December 7, 1983.
Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
Retention time (min) Method
-------------------------- detection
Parameter limit
Column 1 Column 2 ([micro]g/
L)
------------------------------------------------------------------------
1,3-Dichlorobenzene.............. 4.5 6.8 1.19
Hexachloroethane................. 4.9 8.3 0.03
1,4-Dichlorobenzene.............. 5.2 7.6 1.34
1,2-Dichlorobenzene.............. 6.6 9.3 1.14
Hexachlorobutadiene.............. 7.7 20.0 0.34
1,2,4-Trichlorobenzene........... 15.5 22.3 0.05
Hexachlorocyclopentadiene........ nd \c\ 16.5 0.40
2-Chloronaphthalene.............. \a\ 2.7 \b\ 3.6 0.94
Hexachlorobenzene................ \a\ 5.6 \b\ 10.1 0.05
------------------------------------------------------------------------
Column 1 conditions: Supelcoport (100/120 mesh) coated with 1% SP-1000
packed in a 1.8 m x 2 mm ID glass column with 5% methane/95% argon
carrier gas at 25 mL/min. flow rate. Column temperature held
isothermal at 65 [deg]C, except where otherwise indicated.
Column 2 conditions: Supelcoport (80/100 mesh) coated with 1.5% OV-1/
2.4% OV-225 packed in a 1.8 m x 2 mm ID glass column with 5% methane/
95% argon carrier gas at 25 mL/min. flow rate. Column temperature held
isothermal at 75 [deg]C, except where otherwise indicated.
nd = Not determined.
\a\ 150 [deg]C column temperature.
\b\ 165 [deg]C column temperature.
\c\ 100 [deg]C column temperature.
Table 2--QC Acceptance Criteria--Method 612
----------------------------------------------------------------------------------------------------------------
Limit for
Test conc. s Range for X Range for
Parameter ([micro]g/ ([micro]g/ ([micro]g/ P, Ps
L) L) L) (percent)
----------------------------------------------------------------------------------------------------------------
2-Chloronaphthalene............................................. 100 37.3 29.5-126.9 9-148
1,2-Dichlorobenzene............................................. 100 28.3 23.5-145.1 9-160
1,3-Dichlorobenzene............................................. 100 26.4 7.2-138.6 D-150
1,4-Dichlorobenzene............................................. 100 20.8 22.7-126.9 13-137
Hexachlorobenzene............................................... 10 2.4 2.6-14.8 15-159
Hexachlorobutadiene............................................. 10 2.2 D-12.7 D-139
Hexachlorocyclopentadiene....................................... 10 2.5 D-10.4 D-111
Hexachloroethane................................................ 10 3.3 2.4-12.3 8-139
1,2,4-Trichlorobenzene.......................................... 100 31.6 20.2-133.7 5-149
----------------------------------------------------------------------------------------------------------------
s = Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X = Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps = Percent recovery measured (Section 8.3.2, Section 8.4.2).
D = Detected; result must be greater than zero.
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 3.
[[Page 234]]
Table 3--Method Accuracy and Precision as Functions of Concentration--Method 612
----------------------------------------------------------------------------------------------------------------
Single analyst
Parameter Acccuracy, as recovery, precision, sr' Overall precision, S'
X' ([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
2-Chloronaphthalene................... 0.75C + 3.21 0.28X-1.17 0.38X-1.39
1,2-Dichlorobenzene................... 0.85C-0.70 0.22X-2.95 0.41X-3.92
1,3-Dichlorobenzene................... 0.72C + 0.87 0.21X-1.03 0.49X-3.98
1,4-Dichlorobenzene................... 0.72C + 2.80 0.16X-0.48 0.35X-0.57
Hexachlorobenzene..................... 0.87C-0.02 0.14X + 0.07 0.36X-0.19
Hexachlorobutadiene................... 0.61C + 0.03 0.18X + 0.08 0.53X-0.12
Hexachlorocyclopentadiene \a\......... 0.47C 0.24X 0.50X
Hexachloroethane...................... 0.74C-0.02 0.23X + 0.07 0.36X-0.00
1,2,4-Trichlorobenzene................ 0.76C + 0.98 0.23X-0.44 0.40X-1.37
----------------------------------------------------------------------------------------------------------------
X' = Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/L.
sr' = Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S' = Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C = True value for the concentration, in [micro]g/L.
X = Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
\a\ Estimates based upon the performance in a single laboratory. \12\
[[Page 235]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.036
[[Page 236]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.037
[[Page 237]]
Method 613--2,3,7,8-Tetrachlorodibenzo-p-Dioxin
1. Scope and Application
1.1 This method covers the determination of 2,3,7,8-
tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD). The following parameter may
be determined by this method:
------------------------------------------------------------------------
STORET
Parameter No. GAS No.
------------------------------------------------------------------------
2,3,7,8-TCDD..................................... 34675 1746-01-6
------------------------------------------------------------------------
1.2 This is a gas chromatographic/mass spectrometer (GC/MS) method
applicable to the determination of 2,3,7,8-TCDD in municipal and
industrial discharges as provided under 40 CFR 136.1. Method 625 may be
used to screen samples for 2,3,7,8-TCDD. When the screening test is
positive, the final qualitative confirmation and quantification must be
made using Method 613.
1.3 The method detection limit (MDL, defined in Section 14.1) \1\
for 2,3,7,8-TCDD is listed in Table 1. The MDL for a specific wastewater
may be different from that listed, depending upon the nature of
interferences in the sample matrix.
1.4 Because of the extreme toxicity of this compound, the analyst
must prevent exposure to himself, of to others, by materials knows or
believed to contain 2,3,7,8-TCDD. Section 4 of this method contains
guidelines and protocols that serve as minimum safe-handling standards
in a limited-access laboratory.
1.5 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.6 This method is restricted to use by or under the supervision of
analysts experienced in the use of a gas chromatograph/mass spectrometer
and in the interpretation of mass spectra. Each analyst must demonstrate
the ability to generate acceptable results with this method using the
procedure described in Section 8.2.
2. Summary of Method
2.1 A measured volume of sample, approximately 1-L, is spiked with
an internal standard of labeled 2,3,7,8-TCDD and extracted with
methylene chloride using a separatory funnel. The methylene chloride
extract is exchanged to hexane during concentration to a volume of 1.0
mL or less. The extract is then analyzed by capillary column GC/MS to
separate and measure 2,3,7,8-TCDD. \2 3\
2.2 The method provides selected column chromatographic cleanup
proceudres to aid in the elimination of interferences that may be
encountered.
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardware that lead to
discrete artifacts and/or elevated backgrounds at the masses (m/z)
monitored. All of these materials must be routinely demonstrated to be
free from interferences under the conditions of the analysis by running
laboratory reagent blanks as described in Section 8.1.3.
3.1.1 Glassware must be scrupulously cleaned. \4\ Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed by detergent washing with
hot water, and rinses with tap water and distilled water. The glassware
should then be drained dry, and heated in a muffle furnace at 400 [deg]C
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not
be eliminated by the treatment. Solvent rinses with acetone and
pesticide quality hexane may be substituted for the muffle furnace
heating. Thorough rinsing with such solvents usually eliminates PCB
interference. Volumetric ware should not be heated in a muffle furnace.
After drying and cooling, glassware should be sealed and stored in a
clean environment to prevent any accumulation of dust or other
contaminants. Store inverted or capped with aluminum foil.
3.1.2 The use of high purity reagents and solvents helps to
mininmize interference problems. Purification of solvents by
distillation in all-glass systems may be required.
3.2 Matrix interferences may be caused by contaminants that are
coextracted from the sample. The extent of matrix interferences will
vary considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled.
2,3,7,8-TCDD is often associated with other interfering chlorinated
compounds which are at concentrations several magnitudes higher than
that of 2,3,7,8-TCDD. The cleanup producers in Section 11 can be used to
overcome many of these interferences, but unique samples may require
additional cleanup approaches \1 5-7\ to eliminate false positives and
achieve the MDL listed in Table 1.
3.3 The primary column, SP-2330 or equivalent, resolves 2,3,7,8-TCDD
from the other 21 TCDD insomers. Positive results using any other gas
chromatographic column must be confirmed using the primary column.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to
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the lowest possible level by whatever means available. The laboratory is
responsible for maintaining a current awareness file of OSHA regulations
regarding the safe handling of the chemicals specified in this method. A
reference file of material data handling sheets should also be made
available to all personnel involved in the chemical analysis. Additional
references to laboratory safety are available and have been identified
\8-10\ for the information of the analyst. Benzene and 2,3,7,8-TCDD have
been identified as suspected human or mammalian carcinogens.
4.2 Each laboratory must develop a strict safety program for
handling 2,3,7,8-TCDD. The following laboratory practices are
recommended:
4.2.1 Contamination of the laboratory will be minimized by
conducting all manipulations in a hood.
4.2.2 The effluents of sample splitters for the gas chromatograph
and roughing pumps on the GC/MS should pass through either a column of
activated charcoal or be bubbled through a trap containing oil or high-
boiling alcohols.
4.2.3 Liquid waste should be dissolved in methanol or ethanol and
irradiated with ultraviolet light with a wavelength greater than 290 nm
for several days. (Use F 40 BL lamps or equivalent). Analyze liquid
wastes and dispose of the solutions when 2,3,7,8-TCDD can no longer be
detected.
4.3 Dow Chemical U.S.A. has issued the following precautimns
(revised November 1978) for safe handling of 2,3,7,8-TCDD in the
laboratory:
4.3.1 The following statements on safe handling are as complete as
possible on the basis of available toxicological information. The
precautions for safe handling and use are necessarily general in nature
since detailed, specific recommendations can be made only for the
particular exposure and circumstances of each individual use. Inquiries
about specific operations or uses may be addressed to the Dow Chemical
Company. Assistance in evaluating the health hazards of particular plant
conditions may be obtained from certain consulting laboratories and from
State Departments of Health or of Labor, many of which have an
industrial health service. 2,3,7,8-TCDD is extremely toxic to laboratory
animals. However, it has been handled for years without injury in
analytical and biological laboratories. Techniques used in handling
radioactive and infectious materials are applicable to 2,3,7,8,-TCDD.
4.3.1.1 Protective equipment--Throw-away plastic gloves, apron or
lab coat, safety glasses, and a lab hood adequate for radioactive work.
4.3.1.2 Training--Workers must be trained in the proper method of
removing contaminated gloves and clothing without contacting the
exterior surfaces.
4.3.1.3 Personal hygiene--Thorough washing of hands and forearms
after each manipulation and before breaks (coffee, lunch, and shift).
4.3.1.4 Confinement--Isolated work area, posted with signs,
segregated glassware and tools, plastic-backed absorbent paper on
benchtops.
4.3.1.5 Waste--Good technique includes minimizing contaminated
waste. Plastic bag liners should be used in waste cans. Janitors must be
trained in the safe handling of waste.
4.3.1.6 Disposal of wastes--2,3,7,8-TCDD decomposes above 800
[deg]C. Low-level waste such as absorbent paper, tissues, animal
remains, and plastic gloves may be burned in a good incinerator. Gross
quantities (milligrams) should be packaged securely and disposed through
commercial or governmental channels which are capable of handling high-
level radioactive wastes or extremely toxic wastes. Liquids should be
allowed to evaporate in a good hood and in a disposable container.
Residues may then be handled as above.
4.3.1.7 Decontamination--For personal decontamination, use any mild
soap with plenty of scrubbing action. For decontamination of glassware,
tools, and surfaces, Chlorothene NU Solvent (Trademark of the Dow
Chemical Company) is the least toxic solvent shown to be effective.
Satisfactory cleaning may be accomplished by rinsing with Chlorothene,
then washing with any detergent and water. Dishwater may be disposed to
the sewer. It is prudent to minimize solvent wastes because they may
require special disposal through commercial sources which are expensive.
4.3.1.8 Laundry--Clothing known to be contaminated should be
disposed with the precautions described under Section 4.3.1.6. Lab coats
or other clothing worn in 2,3,7,8-TCDD work areas may be laundered.
Clothing should be collected in plastic bags. Persons who convey the
bags and launder the clothing should be advised of the hazard and
trained in proper handling. The clothing may be put into a washer
without contact if the launderer knows the problem. The washer should be
run through a cycle before being used again for other clothing.
4.3.1.9 Wipe tests--A useful method of determining cleanliness of
work surfaces and tools is to wipe the surface with a piece of filter
paper. Extraction and analysis by gas chromatography can achieve a limit
of sensitivity of 0.1 [micro]g per wipe. Less than 1 [micro]g of
2,3,7,8-TCDD per sample indicates acceptable cleanliness; anything
higher warrants further cleaning. More than 10 [micro]g on a wipe sample
constitutes an acute hazard and requires prompt cleaning before further
use of the equipment or work space. A high (10 [micro]g)
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2,3,7,8-TCDD level indicates that unacceptable work practices have been
employed in the past.
4.3.1.10 Inhalation--Any procedure that may produce airborne
contamination must be done with good ventilation. Gross losses to a
ventilation system must not be allowed. Handling of the dilute solutions
normally used in analytical and animal work presents no inhalation
hazards except in the case of an accident.
4.3.1.11 Accidents--Remove contaminated clothing immediately, taking
precautions not to contaminate skin or other articles. Wash exposed skin
vigorously and repeatedly until medical attention is obtained.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--1-L or 1-qt, amber glass, fitted with a
screw cap lined with Teflon. Foil may be substituted for Teflon if the
sample is not corrosive. If amber bottles are not available, protect
samples from light. The bottle and cap liner must be washed, rinsed with
acetone or methylene chloride, and dried before use to minimize
contamination.
5.1.2 Automatic sampler (optional)--The sampler must incorporate
glass sample containers for the collection of a minimum of 250 mL of
sample. Sample containers must be kept refrigerated at 4 [deg]C and
protected from light during compositing. If the sampler uses a
peristaltic pump, a minimum length of compressible silicone rubber
tubing may be used. Before use, however, the compressible tubing should
be thoroughly rinsed with methanol, followed by repeated rinsings with
distilled water to minimize the potential for contamination of the
sample. An integrating flow meter is required to collect flow
proportional composites.
5.1.3 Clearly label all samples as ``POISON'' and ship according to
U.S. Department of Transportation regulations.
5.2 Glassware (All specifications are suggested. Catalog numbers are
included for illustration only.):
5.2.1 Separatory funnels--2-L and 125-mL, with Teflon stopcock.
5.2.2 Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes K-
570050-1025 or equivalent). Calibration must be checked at the volumes
employed in the test. Ground glass stopper is used to prevent
evaporation of extracts.
5.2.3 Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
5.2.4 Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
5.2.5 Snyder column, Kuderna-Danish--Two-ball micro (Kontes K-
569001-0219 or equivalent).
5.2.6 Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
5.2.7 Chromatographic column--300 mm long x 10 mm ID, with Teflon
stopcock and coarse frit filter disc at bottom.
5.2.8 Chromatographic column--400 mm long x 11 mm ID, with Teflon
stopcock and coarse frit filter disc at bottom.
5.3 Boiling chips--Approximately 10/40 mesh. Heat to 400 [deg]C for
30 min or Soxhlet extract with methylene chloride.
5.4 Water bath--Heated, with concentric ring cover, capable of
temperature control (2 [deg]C). The bath should be
used in a hood.
5.5 GC/MS system:
5.5.1 Gas chromatograph--An analytical system complete with a
temperature programmable gas chromatograph and all required accessories
including syringes, analytical columns, and gases. The injection port
must be designed for capillary columns. Either split, splitless, or on-
column injection techniques may be employed, as long as the requirements
of Section 7.1.1 are achieved.
5.5.2 Column--60 m long x 0.25 mm ID glass or fused silica, coated
with SP-2330 (or equivalent) with a film thickness of 0.2 [micro]m. Any
equivalent column must resolve 2, 3, 7, 8-TCDD from the other 21 TCDD
isomers. \16\
5.5.3 Mass spectrometer--Either a low resolution mass spectrometer
(LRMS) or a high resolution mass spectrometer (HRMS) may be used. The
mass spectrometer must be equipped with a 70 V (nominal) ion source and
be capable of aquiring m/z abundance data in real time selected ion
monitoring (SIM) for groups of four or more masses.
5.5.4 GC/MS interface--Any GC to MS interface can be used that
achieves the requirements of Section 7.1.1. GC to MS interfaces
constructed of all glass or glass-lined materials are recommended. Glass
surfaces can be deactivated by silanizing with dichlorodimethylsilane.
To achieve maximum sensitivity, the exit end of the capillary column
should be placed in the ion source. A short piece of fused silica
capillary can be used as the interface to overcome problems associated
with straightening the exit end of glass capillary columns.
5.5.5 The SIM data acquired during the chromatographic program is
defined as the Selected Ion Current Profile (SICP). The SICP can be
acquired under computer control or as a real time analog output. If
computer control is used, there must be software available to plot the
SICP and report peak height or area data for any m/z in the SICP between
specified time or scan number limits.
5.6 Balance--Analytical, capable of accurately weighing 0.0001 g.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of 2, 3, 7, 8-TCDD.
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6.2 Sodium hydroxide solution (10 N)--Dissolve 40 g of NaOH (ACS) in
reagent water and dilute to 100 mL. Wash the solution with methylene
chloride and hexane before use.
6.3 Sodium thiosulfate--(ACS) Granular.
6.4 Sulfuric acid--Concentrated (ACS, sp. gr. 1.84).
6.5 Acetone, methylene chloride, hexane, benzene, ortho-xylene,
tetradecane--Pesticide quality or equivalent.
6.6 Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at
400 [deg]C for 4 h in a shallow tray.
6.7 Alumina--Neutral, 80/200 mesh (Fisher Scientific Co., No. A-540
or equivalent). Before use, activate for 24 h at 130 [deg]C in a foil-
covered glass container.
6.8 Silica gel--High purity grade, 100/120 mesh (Fisher Scientific
Co., No. S-679 or equivalent).
6.9 Stock standard solutions (1.00 [micro]g/[micro]L)--Stock
standard solutimns can be prepared from pure standard materials or
purchased as certified solutions. Acetone should be used as the solvent
for spiking solutions; ortho-xylene is recommended for calibration
standards for split injectors; and tetradecane is recommended for
splitless or on-colum injectors. Analyze stock internal standards to
verify the absence of native 2,3,7,8-TCDD.
6.9.1 Prepare stock standard solutions of 2,3,7,8-TCDD (mol wt 320)
and either \37\C14 2,3,7,8-TCDD (mol wt 328) or
\13\C112 2,3,7,8-TCDD (mol wt 332) in an isolated area by
accurately weighing about 0.0100 g of pure material. Dissolve the
material in pesticide quality solvent and dilute to volume in a 10-mL
volumetric flask. When compound purity is assayed to be 96% or greater,
the weight can be used without correction to calculate the concentration
of the stock standard. Commercially prepared stock standards can be used
at any concentration if they are certified by the manufacturer or by an
independent source.
6.9.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles. Store in an isolated refrigerator protected from
light. Stock standard solutions should be checked frequently for signs
of degradation or evaporation, especially just prior to preparing
calibration standards or spiking solutions from them.
6.9.3 Stock standard solutions must be replaced after six months, or
sooner if comparison with check standards indicates a problem.
6.10 Internal standard spiking solution (25 ng/mL)--Using stock
standard solution, prepare a spiking solution in acetone of either \13\
Cl12 or \37\ Cl4 2,3,7,8-TCDD at a concentration
of 25 ng/mL. (See Section 10.2)
6.11 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Establish gas chromatograhic operating conditions equivalent to
those given in Table 1 and SIM conditions for the mass spectrometer as
described in Section 12.2 The GC/MS system must be calibrated using the
internal standard technique.
7.1.1 Using stock standards, prepare calibration standards that will
allow measurement of relative response factors of at least three
concentration ratios of 2,3,7,8-TCDD to internal standard. Each
calibration standard must be prepared to contain the internal standard
at a concentration of 25 ng/mL. If any interferences are contributed by
the internal standard at m/z 320 and 322, its concentration may be
reduced in the calibration standards and in the internal standard
spiking solution (Section 6.10). One of the calibration standards should
contain 2,3,7,8-TCDD at a concentration near, but above, the MDL and the
other 2,3,7,8-TCDD concentrations should correspond to the expected
range of concentrations found in real samples or should define the
working range of the GC/MS system.
7.1.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standardaccording to Section 12 and tabulate peak height or area
response against the concentration of 2,3,7,8-TCDD and internal
standard. Calculate response factors (RF) for 2,3,7,8-TCDD using
Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.122
Equation 1
where:
As = SIM response for 2,3,7,8-TCDD m/z 320.
Ais = SIM response for the internal standard, m/z 332 for
\13\ C12 2,3,7,8-TCDD m/z 328 for \37\
Cl4 2,3,7,8-TCDD.
Cis = Concentration of the internal standard ([micro]g/L).
Cs = Concentration of 2,3,7,8-TCDD ([micro]g/L).
If the RF value over the working range is a constant (<10% relative
standard deviation, RSD), the RF can be assumed to be invariant and the
average RF can be used for calculations. Alternatively, the results can
be used to plot a calibration curve of response ratios, As/
Ais, vs. RF.
7.1.3 The working calibration curve or RF must be verified on each
working day by the measurement of one or more 2,3,7,8-TCDD calibration
standards. If the response for 2,3,7,8-TCDD varies from the predicted
response by more than 15%, the test must be
repeated using a fresh calibration standard. Alternatively, a new
calibration curve must be prepared.
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7.2 Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the reagents.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Sections 10.5, 11.1, and 12.1) to improve the separations or lower the
cost of measurements. Each time such a modification is made to the
method, the analyst is required to repeat the procedure in Section 8.2
8.1.3 Before processing any samples, the analyst must analyze a
reagent water blank to demonstrate that interferences from the
analytical system and glassware are under control. Each time a set of
samples is extracted or reagents are changed, a reagent water blank must
be processed as a safeguard against laboratory contamination.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples with native 2,3,7,8-TCDD to monitor and
evaluate laboratory data quality. This procedure is described in Section
8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing 2,3,7,8-TCDD at a concentration of 0.100 [micro]g/mL in
acetone. The QC check sample concentrate must be obtained from the U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory in Cincinnati, Ohio, if available. If not available from that
source, the QC check sample concentrate must be obtained from another
external source. If not available from either source above, the QC check
sample concentrate must be prepared by the laboratory using stock
standards prepared independently from those used for calibration.
8.2.2 Using a pipet, prepare QC check samples at a concentration of
0.100 [micro]g/L (100 ng/L) by adding 1.00 mL of QC check sample
concentrate to each of four 1-L aliquots of reagent water.
8.2.3 Analyze the well-mixed QC check samples according to the
method beginning in Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for 2,3,7,8-TCDD
using the four results.
8.2.5 Compare s and (X) with the corresponding acceptance criteria
for precision and accuracy, respectively, found in Table 2. If s and X
meet the acceptance criteria, the system performance is acceptable and
analysis of actual samples can begin. If s exceeds the precision limit
or X falls outside the range for accuracy, the system performance is
unacceptable for 2,3,7,8-TCDD. Locate and correct the source of the
problem and repeat the test beginning with Section 8.2.2.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of
2,3,7,8-TCDD in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of 2,3,7,8-TCDD in the sample is not
being checked against a limit specific to that parameter, the spike
should be at 0.100 [micro]g/L or 1 to 5 times higher than the background
concentration determined in Section 8.3.2, whichever concentration would
be larger.
8.3.1.3 If it is impractical to determine background levels before
spiking (e.g., maximum holding times will be exceeded), the
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spike concentration should be (1) the regulatory concentration limit, if
any; or, if none (2) the larger of either 5 times higher than the
expected background concentration or 0.100 [micro]g/L.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of 2,3,7,8-TCDD. If necessary, prepare a new QC check
sample concentrate (Section 8.2.1) appropriate for the background
concentration in the sample. Spike a second sample aliquot with 1.0 mL
of the QC check sample concentrate and analyze it to determine the
concentration after spiking (A) of 2,3,7,8-TCDD. Calculate percent
recovery (P) as 100(A-B)%T, where T is the known true value of the
spike.
8.3.3 Compare the percent recovery (P) for 2,3,7,8-TCDD with the
corresponding QC acceptance criteria found in Table 2. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\11\ If spiking was performed at a concentration lower than 0.100
[micro]g/L, the analyst must use either the QC acceptance criteria in
Table 2, or optional QC acceptance criteria calculated for the specific
spike concentration. To calculate optional acceptance criteria for the
recovery of 2,3,7,8-TCDD: (1) Calculate accuracy (X') using the equation
in Table 3, substituting the spike concentration (T) for C; (2)
calculate overall precision (S') using the equation in Table 3,
substituting X' for X; (3) calculate the range for recovery at the spike
concentration as (100 X'/T)2.44(100 S'/T)%. \11\
8.3.4 If the recovery of 2,3,7,8-TCDD falls outside the designated
range for recovery, a check standard must be analyzed as described in
Section 8.4.
8.4 If the recovery of 2,3,7,8-TCDD fails the acceptance criteria
for recovery in Section 8.3, a QC check standard must be prepared and
analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the complexity of the sample matrix and the performance
of the laboratory.
8.4.1 Prepare the QC check standard by adding 1.0 mL of QC check
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of 2,3,7,8-TCDD. Calculate the percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) with the
corresponding QC acceptance criteria found in Table 2. If the recovery
of 2,3,7,8-TCDD falls outside the designated range, the laboratory
performance is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for 2,3,7,8-
TCDD in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the spandard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2sp to P + 2sp.
If P = 90% and sp = 10%, for example, the accuracy interval
is expressed as 70-110%. Update the accuracy assessment on a regular
basis (e.g. after each five to ten new accuracy measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevant performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices \12\ should be followed, except that the bottle must
not be prerinsed with sample before collection. Composite samples should
be collected in refrigerated glass containers in accordance with the
requirements of the program. Automatic sampling equipment must be as
free as possible of Tygon tubing and other potential sources of
contamination.
9.2 All samples must be iced or refrigerated at 4 [deg]C and
protected from light from the time of collection until extraction. Fill
the sample bottles and, if residual chlorine is present, add 80 mg of
sodium thiosulfate per liter of sample and mix well. EPA Methods 330.4
and 330.5 may be used for measurement of residual chlorine. \13\ Field
test kits are available for this purpose.
9.3 Label all samples and containers ``POISON'' and ship according
to applicable U.S. Department of Transportation regulations.
9.4 All samples must be extracted within 7 days of collection and
completely analyzed within 40 days of extraction. \2\
10. Sample Extraction
Caution: When using this method to analyze for 2,3,7,8-TCDD, all of
the following operations must be performed in a limited-access
laboratory with the analyst wearing full
[[Page 243]]
protective covering for all exposed skin surfaces. See Section 4.2.
10.1 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Pour the entire sample into a 2-L
separatory funnel.
10.2 Add 1.00 mL of internal standard spiking solution to the sample
in the separatory funnel. If the final extract will be concentrated to a
fixed volume below 1.00 mL (Section 12.3), only that volume of spiking
solution should be added to the sample so that the final extract will
contain 25 ng/mL of internal standard at the time of analysis.
10.3 Add 60 mL of methylene chloride to the sample bottle, seal, and
shake 30 s to rinse the inner surface. Transfer the solvent to the
separatory funnel and extract the sample by shaking the funnel for 2
min. with periodic venting to release excess pressure. Allow the organic
layer to separate from the water phase for a minimum of 10 min. If the
emulsion interface between layers is more than one-third the vmlume of
the solvent layer, the analyst must employ mechanical techniques to
complete the phase separation. The optimum technique depends upon the
sample, but may include stirring, filtration of the emulsion through
glass wool, centrifugation, or other physical methods. Collect the
methylene chloride extract in a 250-mL Erlenmeyer flask.
10.4 Add a second 60-mL volume of methylene chloride to the sample
bottle and repeat the extraction procedure a second time, combining the
extracts in the Erlenmeyer flask. Perform a third extraction in the same
manner.
10.5 Assemble a Kuderna-Danish (K-D) concentrator by attaching a 10-
mL concentrator tube to a 500-mL evaporative flask. Other concentration
devices or techniques may be used in place of the K-D concentrator if
the requirements of Section 8.2 are met.
10.6 Pour the combined extract into the K-D concentrator. Rinse the
Erlenmeyer flask with 20 to 30 mL of methylele chloride to complete the
quantitative transfer.
10.7 Add one or two clean boiling chips to the evaporative flask and
attach a three-ball Snyder column. Prewet the Snyder column by adding
about 1 mL of methylene chloride to the top. Place the K-D apparatus on
a hot water bath (60 to 65 [deg]C) so that the concentrator tube is
partially immersed in the hot water, and the entire lower rounded
surface of the flask is bathed with hot vapor. Adjust the vertical
position of the apparatus and the water temperature as required to
complete the concentration in 15 to 20 min. At the proper rate of
distillation the balls of the column will actively chatter but the
chambers will not flood with condensed solvent. When the apparent volume
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain
and cool for at least 10 min.
10.8 Momentarily remove the Snyder column, add 50 mL of hexane and a
new boiling chip, and reattach the Snyder column. Raise the temperature
of the water bath to 85 to 90 [deg]C. Concentrate the extract as in
Section 10.7, except use hexane to prewet the column. Remove the Snyder
column and rinse the flask and its lower joint into the concentrator
tube with 1 to 2 mL of hexane. A 5-mL syringe is recommended for this
operation. Set aside the K-D glassware for reuse in Section 10.14.
10.9 Pour the hexane extract from the concentrator tube into a 125-
mL separatory funnel. Rinse the concentrator tube four times with 10-mL
aliquots of hexane. Combine all rinses in the 125-mL separatory funnel.
10.10 Add 50 mL of sodium hydroxide solution to the funnel and shake
for 30 to 60 s. Discard the aqueous phase.
10.11 Perform a second wash of the organic layer with 50 mL of
reagent water. Discard the aqueous phase.
10.12 Wash the hexane layer with a least two 50-mL aliquots of
concentrated sulfuric acid. Continue washing the hexane layer with 50-mL
aliquots of concentrated sulfuric acid until the acid layer remains
colorless. Discard all acid fractions.
10.13 Wash the hexane layer with two 50-mL aliquots of reagent
water. Discard the aqueous phases.
10.14 Transfer the hexane extract into a 125-mL Erlenmeyer flask
containing 1 to 2 g of anhydrous sodium sulfate. Swirl the flask for 30
s and decant the hexane extract into the reassembled K-D apparatus.
Complete the quantitative transfer with two 10-mL hexane rinses of the
Erlenmeyer flask.
10.15 Replace the one or two clean boiling chips and concentrate the
extract to 6 to 10 mL as in Section 10.8.
10.16 Add a clean boiling chip to the concentrator tube and attach a
two-ball micro-Snyder column. Prewet the column by adding about 1 mL of
hexane to the top. Place the micro-K-D apparatus on the water bath so
that the concentrator tube is partially immersed in the hot water.
Adjust the vertical position of the apparatus and the water temperature
as required to complete the concentration in 5 to 10 min. At the proper
rate of distillation the balls of the column will actively chatter but
the chambers will not flood. When the apparent volume of liquid reaches
about 0.5 mL, remove the K-D apparatus and allow it to drain and cool
for at least 10 min. Remove the micro-Snyder column and rinse its lower
joint into the concentrator tube with 0.2 mL of hexane.
Adjust the extract volume to 1.0 mL with hexane. Stopper the
concentrator tube and store refrigerated and protected from light if
further processing will not be performed immediately. If the extract
will be stored
[[Page 244]]
longer than two days, it should be transferred to a Teflon-sealed screw-
cap vial. If the sample extract requires no further cleanup, proceed
with GC/MS analysis (Section 12). If the sample requires further
cleanup, proceed to Section 11.
10.17 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to a 1000-mL graduated
cylinder. Record the sample volume to the nearest 5 mL.
11. Cleanup and Separation
11.1 Cleanup procedures may not be necessary for a relatively clean
sample matrix. If particular circumstances demand the use of a cleanup
procedure, the analyst may use either procedure below or any other
appropriate procedure. \1 5-7\ However, the analyst first must
demonstrate that the requirements of Section 8.2 can be met using the
method as revised to incorporate the cleanup procedure. Two cleanup
column options are offered to the analyst in this section. The alumina
column should be used first to overcome interferences. If background
problems are still encountered, the silica gel column may be helpful.
11.2 Alumina column cleanup for 2,3,7,8-TCDD:
11.2.1 Fill a 300 mm long x 10 mm ID chromatographic column with
activated alumina to the 150 mm level. Tap the column gently to settle
the alumina and add 10 mm of anhydrous sodium sulfate to the top.
11.2.2 Preelute the column with 50 mL of hexane. Adjust the elution
rate to 1 mL/min. Discard the eluate and just prior to exposure of the
sodium sulfate layer to the air, quantitatively transfer the 1.0-mL
sample extract onto the column using two 2-mL portions of hexane to
complete the transfer.
11.2.3 Just prior to exposure of the sodium sulfate layer to the
air, add 50 mL of 3% methylene chloride/95% hexane (V/V) and continue
the elution of the column. Discard the eluate.
11.2.4 Next, elute the column with 50 mL of 20% methylene chloride/
80% hexane (V/V) into a 500-mL K-D flask equipped with a 10-mL
concentrator tube. Concentrate the collected fraction to 1.0 mL as in
Section 10.16 and analyze by GC/MS (Section 12).
11.3 Silica gel column cleanup for 2,3,7,8-TCDD:
11.3.1 Fill a 400 mm long x 11 mm ID chromatmgraphic column with
silica gel to the 300 mm level. Tap the column gently to settle the
silica gel and add 10 mm of anhydrous sodium sulfate to the top.
11.3.2 Preelute the column with 50 mL of 20% benzene/80% hexane (V/
V). Adjust the elution rate to 1 mL/min. Discard the eluate and just
prior to exposure of the sodium sulfate layer to the air, quantitatively
transfer the 1.0-mL sample extract onto the column using two 2-mL
portions of 20% benzene/80% hexane to complete the transfer.
11.3.3 Just prior to exposure of the sodium sulfate layer to the
air, add 40 mL of 20% benzene/80% hexane to the column. Collect the
eluate in a clean 500-mL K-D flask equipped with a 10-mL concentrator
tube. Concentrate the collected fraction to 1.0 mL as in Section 10.16
and analyze by GC/MS.
12. GC/MS Analysis
12.1 Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are retention times and MDL
that can be achieved under these conditions. Other capillary columns or
chromatographic conditions may be used if the requirements of Sections
5.5.2 and 8.2 are met.
12.2 Analyze standards and samples with the mass spectrometer
operating in the selected ion monitoring (SIM) mode using a dwell time
to give at least seven points per peak. For LRMS, use masses at m/z 320,
322, and 257 for 2,3,7,8-TCDD and either m/z 328 for \37\Cl4
2,3,7,8-TCDD or m/z 332 for \13\C12 2,3,7,8-TCDD. For HRMS,
use masses at m/z 319.8965 and 321.8936 for 2,3,7,8-TCDD and either m/z
327.8847 for \37\Cl4 2,3,7,8-TCDD or m/z 331.9367 for
\13\C12 2,3,7,8-TCDD.
12.3 If lower detection limits are required, the extract may be
carefully evaporated to dryness under a gentle stream of nitrogen with
the concentrator tube in a water bath at about 40 [deg]C. Conduct this
operation immediately before GC/MS analysis. Redissolve the extract in
the desired final volume of ortho-xylene or tetradecane.
12.4 Calibrate the system daily as described in Section 7.
12.5 Inject 2 to 5 [micro]L of the sample extract into the gas
chromatograph. The volume of calibration standard injected must be
measured, or be the same as all sample injection volumes.
12.6 The presence of 2,3,7,8-TCDD is qualitatively confirmed if all
of the following criteria are achieved:
12.6.1 The gas chromatographic column must resolve 2,3,7,8-TCDD from
the other 21 TCDD isomers.
12.6.2 The masses for native 2,3,7,8-TCDD (LRMS-m/z 320, 322, and
257 and HRMS-m/z 320 and 322) and labeled 2,3,7,8-TCDD (m/z 328 or 332)
must exhibit a simultaneous maximum at a retention time that matches
that of native 2,3,7,8-TCDD in the calibration standard, with the
performance specifications of the analytical system.
12.6.3 The chlorine isotope ratio at m/z 320 and m/z 322 must agree
to within10% of that in the calibration standard.
12.6.4 The signal of all peaks must be greater than 2.5 times the
noise level.
12.7 For quantitation, measure the response of the m/z 320 peak for
2,3,7,8-TCDD
[[Page 245]]
and the m/z 332 peak for \13\C12 2,3,7,8-TCDD or the m/z 328
peak for \37\Cl4 2,3,7,8-TCDD.
12.8 Co-eluting impurities are suspected if all criteria are
achieved except those in Section 12.6.3. In this case, another SIM
analysis using masses at m/z 257, 259, 320 and either m/a 328 or m/z 322
can be performed. The masses at m/z 257 and m/z 259 are indicative of
the loss of one chlorine and one carbonyl group from 2,3,7,8-TCDD. If
masses m/z 257 and m/z 259 give a chlorine isotope ratio that agrees to
within 10% of the same cluster in the calibration
standards, then the presence of TCDD can be confirmed. Co-eluting DDD,
DDE, and PCB residues can be confirmed, but will require another
injection using the appropriate SIM masses or full repetitive mass
scans. If the response for \37\Cl4 2,3,7,8-TCDD at m/z 328 is
too large, PCB contamination is suspected and can be confirmed by
examining the response at both m/z 326 and m/z 328. The
\37\Cl4 2,3,7,8-TCDD internal standard gives negligible
response at m/z 326. These pesticide residues can be removed using the
alumina column cleanup procedure.
12.9 If broad background interference restricts the sensitivity of
the GC/MS analysis, the analyst should employ additional cleanup
procedures and reanalyze by GC/MS.
12.10 In those circumstances where these procedures do not yield a
definitive conclusion, the use of high resolution mass spectrometry is
suggested. \5\
13. Calculations
13.1 Calculate the concentration of 2,3,7,8-TCDD in the sample using
the response factor (RF) determined in Section 7.1.2 and Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.123
Equation 2
where:
As = SIM response for 2,3,7,8-TCDD at m/z 320.
Ais = SIM response for the internal standard at m/z 328 or
332.
Is = Amount of internal standard added to each extract
([micro]g).
Vo = Volume of water extracted (L).
13.2 For each sample, calculate the percent recovery of the internal
standard by comparing the area of the m/z peak measured in the sample to
the area of the same peak in the calibration standard. If the recovery
is below 50%, the analyst should review all aspects of his analytical
technique.
13.3 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
14. Method Performance
14.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentration
listed in Table 1 was obtained using reagent water. \14\ The MDL
actually achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
14.2 This method was tested by 11 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
at six concentrations over the range 0.02 to 0.20 [micro]g/L. \15\
Single operator precision, overall precision, and method accuracy were
found to be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 3.
References
1. 40 CFR part 136, appendix B.
2. ``Determination of TCDD in Industrial and Municipal
Wastewaters,'' EPA 600/4-82-028, National Technical Information Service,
PB82-196882, Springfield, Virginia 22161, April 1982.
3. Buser, H.R., and Rappe, C. ``High Resolution Gas Chromatography
of the 22 Tetrachlorodibenzo-p-dioxin Isomers,'' Analytical Chemistry,
52, 2257 (1980).
4. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard
Practices for Preparation of Sample Containers and for Preservation of
Organic Constituents,'' American Society for Testing and Materials,
Philadelphia.
5. Harless, R. L., Oswald, E. O., and Wilkinson, M. K. ``Sample
Preparation and Gas Chromatography/Mass Spectrometry Determination of
2,3,7,8-Tetrachlorodibenzo-p-dioxin,'' Analytical Chemistry, 52, 1239
(1980).
6. Lamparski, L. L., and Nestrick, T. J. ``Determination of Tetra-,
Hepta-, and Octachlorodibenzo-p-dioxin Isomers in Particulate Samples at
Parts per Trillion Levels,'' Analytical Chemistry, 52, 2045 (1980).
7. Longhorst, M. L., and Shadoff, L. A. ``Determination of Parts-
per-Trillion Concentrations of Tetra-, Hexa-, and Octachlorodibenzo-p-
dioxins in Human Milk,'' Analytical Chemistry, 52, 2037 (1980).
8. ``Carcinogens--Working with Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
9. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occuptional Safety and Health Administration, OSHA 2206
(Revised, January 1976).
[[Page 246]]
10. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
11. Provost, L. P., and Elder, R. S., ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value 1.22
derived in this report.)
12. ASTM Annual Book of Standards, Part 31, D3370-76, ``Standard
Practices for Sampling Water,'' American Society for Testing and
Materials, Philadelphia.
13. ``Methods, 330.4 (Titrimetric, DPD-FAS) and 330.5
(Spectrophotometric DPD) for Chlorine, Total Residual,'' Methods for
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268, March 1979.
14. Wong, A.S. et al. ``The Determination of 2,3,7,8-TCDD in
Industrial and Municipal Wastewaters, Method 613, Part 1--Development
and Detection Limits,'' G. Choudhay, L. Keith, and C. Ruppe, ed.,
Butterworth Inc., (1983).
15. ``EPA Method Study 26, Method 613: 2,3,7,8-Tetrachlorodibenzo-p-
dioxin,'' EPA 600/4-84-037, National Technical Information Service,
PB84-188879, Springfield, Virginia 22161, May 1984.
Table 1--Chromatographic Conditions and Method Detection Limit
------------------------------------------------------------------------
Method
Retention detection
Parameter time limit
(min) ([micro]g/
L)
------------------------------------------------------------------------
2,3,7,8-TCDD..................................... 13.1 0.002
------------------------------------------------------------------------
Column conditions: SP-2330 coated on a 60 m long x 0.25 mm ID glass
column with hydrogen carrier gas at 40 cm/sec linear velocity,
splitless injection using tetradecane. Column temperature held
isothermal at 200 [deg]C for 1 min, then programmed at 8 [deg]C/min to
250 [deg]C and held. Use of helium carrier gas will approximately
double the retention time.
Table 2--QC Acceptance Criteria--Method 613
----------------------------------------------------------------------------------------------------------------
Limit for
Test conc. s Range for X Range
Parameter ([micro]g/ ([micro]g/ ([micro]g/L) for P,
L) L) Ps (%)
----------------------------------------------------------------------------------------------------------------
2,3,7,8-TCDD................................................... 0.100 0.0276 0.0523-0.1226 45-129
----------------------------------------------------------------------------------------------------------------
s = Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X = Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps = Percent recovery measured (Section 8.3.2, Section 8.4.2).
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 3.
Table 3--Method Accuracy and Precision as Functions of Concentration--Method 613
----------------------------------------------------------------------------------------------------------------
Accuracy, as Single analyst,
Parameter recovery, X'' precision, sr'' Overall precision,
([micro]g/L) ([micro]/L) S'' ([micro]/g/L)
----------------------------------------------------------------------------------------------------------------
2,3,7,8-TCDD........................................ 0.86C + 0.00145 0.13X + 0.00129 0.19X + 0.00028
----------------------------------------------------------------------------------------------------------------
X' = Expected recovery for one or more measurements. of a sample containing a concentration of C, in [micro]g/L.
sr' = Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S' = Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C = True value for the concentration, in [micro]g/L.
X = Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
Method 624.1--Purgeables by GC/MS
1. Scope and Application
1.1 This method is for determination of purgeable organic pollutants
in industrial discharges and other environmental samples by gas
chromatography combined with mass spectrometry (GC/MS), as provided
under 40 CFR 136.1. This revision is based on previous protocols
(References 1--3), on the revision promulgated October 26, 1984, and on
an interlaboratory method validation study (Reference 4). Although this
method was validated through an interlaboratory study conducted in the
early 1980s, the fundamental chemistry principles used in this method
remain sound and continue to apply.
1.2 The analytes that may be qualitatively and quantitatively
determined using this method and their CAS Registry numbers are listed
in Table 1. The method may be extended to determine the analytes listed
in Table 2; however, poor purging efficiency or gas chromatography of
some of these analytes may make quantitative determination difficult.
For example, an elevated temperature may be required to purge some
analytes from water. If an elevated temperature is used, calibration and
all quality control (QC) tests must be performed at the elevated
temperature. EPA encourages the use of this method to determine
additional compounds amenable to purge-and-trap GC/MS.
1.3 The large number of analytes in Tables 1 and 2 of this method
makes testing difficult if all analytes are determined simultaneously.
Therefore, it is necessary to determine and perform QC tests for
``analytes of interest'' only. Analytes of interest are those required
to be determined by a regulatory/control authority or in a permit, or by
a client. If a list of analytes is not specified, the
[[Page 247]]
analytes in Table 1 must be determined, at a minimum, and QC testing
must be performed for these analytes. The analytes in Table 1 and some
of the analytes in Table 2 have been identified as Toxic Pollutants (40
CFR 401.15), expanded to a list of Priority Pollutants (40 CFR part 423,
appendix A).
1.4 Method detection limits (MDLs; Reference 5) for the analytes in
Table 1 are listed in that table. These MDLs were determined in reagent
water (Reference 6). Advances in analytical technology, particularly the
use of capillary (open-tubular) columns, allowed laboratories to
routinely achieve MDLs for the analytes in this method that are 2-10
times lower than those in the version promulgated in 1984. The MDL for a
specific wastewater may differ from those listed, depending on the
nature of interferences in the sample matrix.
1.4.1 EPA has promulgated this method at 40 CFR part 136 for use in
wastewater compliance monitoring under the National Pollutant Discharge
Elimination System (NPDES). The data reporting practices described in
section 13.2 are focused on such monitoring needs and may not be
relevant to other uses of the method.
1.4.2 This method includes ``reporting limits'' based on EPA's
``minimum level'' (ML) concept (see the glossary in section 20). Table 1
contains MDL values and ML values for many of the analytes. The MDL for
an analyte in a specific wastewater may differ from that listed in Table
1, depending upon the nature of interferences in the sample matrix.
1.5 This method is performance-based. It may be modified to improve
performance (e.g., to overcome interferences or improve the accuracy of
results) provided all performance requirements are met.
1.5.1 Examples of allowed method modifications are described at 40
CFR 136.6. Other examples of allowed modifications specific to this
method are described in section 8.1.2.
1.5.2 Any modification beyond those expressly allowed at 40 CFR
136.6 or in section 8.1.2 of this method shall be considered a major
modification that is subject to application and approval of an alternate
test procedure under 40 CFR 136.4 and 136.5.
1.5.3 For regulatory compliance, any modification must be
demonstrated to produce results equivalent or superior to results
produced by this method when applied to relevant wastewaters (section
8.3).
1.6 This method is restricted to use by or under the supervision of
analysts experienced in the operation of a purge-and-trap system and a
gas chromatograph/mass spectrometer and in the interpretation of mass
spectra. Each analyst must demonstrate the ability to generate
acceptable results with this method using the procedure in section 8.2.
1.7 Terms and units of measure used in this method are given in the
glossary at the end of the method.
2. Summary of Method
2.1 A gas is bubbled through a measured volume of water in a
specially-designed purging chamber. The purgeables are efficiently
transferred from the aqueous phase to the vapor phase. The vapor is
swept through a sorbent trap where the purgeables are trapped. After
purging is completed, the trap is heated and backflushed with the gas to
desorb the purgeables onto a gas chromatographic column. The column is
temperature programmed to separate the purgeables which are then
detected with a mass spectrometer.
2.2 Different sample sizes in the range of 5-25 mL are allowed in
order to meet differing sensitivity requirements. Calibration and QC
samples must have the same volume as field samples.
3. Interferences
3.1 Impurities in the purge gas, organic compounds outgassing from
the plumbing ahead of the trap, and solvent vapors in the laboratory
account for the majority of contamination problems. The analytical
system must be demonstrated to be free from contamination under the
conditions of the analysis by analyzing blanks initially and with each
analytical batch (samples analyzed on a given 12-hour shift, to a
maximum of 20 samples), as described in Section 8.5. Fluoropolymer
tubing, fittings, and thread sealant should be used to avoid
contamination.
3.2 Samples can be contaminated by diffusion of volatile organics
(particularly fluorocarbons and methylene chloride) through the septum
seal into the sample during shipment and storage. Protect samples from
sources of volatiles during collection, shipment, and storage. A reagent
water field blank carried through sampling and analysis can serve as a
check on such contamination.
3.3 Contamination by carry-over can occur whenever high level and
low level samples are analyzed sequentially. To reduce the potential for
carry-over, the purging device and sample syringe must be rinsed with
reagent water between sample analyses. Whenever an unusually
concentrated sample is encountered, it should be followed by an analysis
of a blank to check for cross contamination. For samples containing
large amounts of water-soluble materials, suspended solids, high boiling
compounds or high purgeable levels, it may be necessary to wash the
purging device with a detergent solution, rinse it with distilled water,
and then dry it in a 105 [deg]C oven between analyses. The trap and
other parts of the system are also subject to contamination; therefore,
frequent bakeout
[[Page 248]]
and purging of the entire system may be required. Screening samples at
high dilution may prevent introduction of contaminants into the system.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible
level. The laboratory is responsible for maintaining a current awareness
file of OSHA regulations regarding the safe handling of the chemicals
specified in this method. A reference file of safety data sheets (SDSs,
OSHA, 29 CFR 1910.1200(g)) should also be made available to all
personnel involved in sample handling and chemical analysis. Additional
references to laboratory safety are available and have been identified
(References 7-9) for the information of the analyst.
4.2. The following analytes covered by this method have been
tentatively classified as known or suspected human or mammalian
carcinogens: Benzene; carbon tetrachloride; chloroform; 1,4-
dichlorobenzene; 1,2-dichloroethane; 1,2-dichloropropane; methylene
chloride; tetrachloroethylene; trichloroethylene; and vinyl chloride.
Primary standards of these toxic compounds should be prepared in a
chemical fume hood, and a NIOSH/MESA approved toxic gas respirator
should be worn when handling high concentrations of these compounds.
4.3 This method allows the use of hydrogen as a carrier gas in place
of helium (Section 5.3.1.2). The laboratory should take the necessary
precautions in dealing with hydrogen, and should limit hydrogen flow at
the source to prevent buildup of an explosive mixture of hydrogen in
air.
5. Apparatus and Materials
Note: Brand names, suppliers, and part numbers are cited for
illustration purposes only. No endorsement is implied. Equivalent
performance may be achieved using equipment and materials other than
those specified here. Demonstration of equivalent performance that meets
the requirements of this method is the responsibility of the laboratory.
Suppliers for equipment and materials in this method may be found
through an on-line search.
5.1 Sampling equipment for discrete sampling.
5.1.1 Vial--25- or 40-mL capacity, or larger, with screw cap with a
hole in the center (Fisher 13075 or equivalent). Unless pre-cleaned,
detergent wash, rinse with tap and reagent water, and dry at 105 5 [deg]C before use.
5.1.2 Septum--Fluoropolymer-faced silicone (Fisher 12722 or
equivalent). Unless pre-cleaned, detergent wash, rinse with tap and
reagent water, and dry at 105 5 [deg]C for one
hour before use.
5.2 Purge-and-trap system--The purge-and-trap system consists of
three separate pieces of equipment: A purging device, trap, and
desorber. Several complete systems are commercially available with
autosamplers. Any system that meets the performance requirements in this
method may be used.
5.2.1 The purging device should accept 5- to 25-mL samples with a
water column at least 3 cm deep. The purge gas must pass though the
water column as finely divided bubbles. The purge gas must be introduced
no more than 5 mm from the base of the water column. Purge devices of a
different volume may be used so long as the performance requirements in
this method are met.
5.2.2 The trap should be at least 25 cm long and have an inside
diameter of at least 0.105 in. The trap should be packed to contain the
following minimum lengths of adsorbents: 1.0 cm of methyl silicone
coated packing (section 6.3.2), 15 cm of 2,6-diphenylene oxide polymer
(section 6.3.1), and 8 cm of silica gel (section 6.3.3). A trap with
different dimensions and packing materials is acceptable so long as the
performance requirements in this method are met.
5.2.3 The desorber should be capable of rapidly heating the trap to
the temperature necessary to desorb the analytes of interest, and of
maintaining this temperature during desorption. The trap should not be
heated higher than the maximum temperature recommended by the
manufacturer.
5.2.4 The purge-and-trap system may be assembled as a separate unit
or coupled to a gas chromatograph.
5.3 GC/MS system.
5.3.1 Gas chromatograph (GC)--An analytical system complete with a
temperature programmable gas chromatograph and all required accessories,
including syringes and analytical columns. Autosamplers designed for
purge-and-trap analysis of volatiles also may be used.
5.3.1.1 Injection port--Volatiles interface, split, splitless,
temperature programmable split/splitless (PTV), large volume, on-column,
backflushed, or other.
5.3.1.2 Carrier gas--Data in the tables in this method were obtained
using helium carrier gas. If another carrier gas is used, analytical
conditions may need to be adjusted for optimum performance, and
calibration and all QC tests must be performed with the alternative
carrier gas. See Section 4.3 for precautions regarding the use of
hydrogen as a carrier gas.
5.3.2 GC column--See the footnote to Table 3. Other columns or
column systems may be used provided all requirements in this method are
met.
[[Page 249]]
5.3.3 Mass spectrometer--Capable of repetitively scanning from 35-
260 Daltons (amu) every 2 seconds or less, utilizing a 70 eV (nominal)
electron energy in the electron impact ionization mode, and producing a
mass spectrum which meets all criteria in Table 4 when 50 ng or less of
4-bromofluorobenzene (BFB) is injected through the GC inlet. If
acrolein, acrylonitrile, chloromethane, and vinyl chloride are to be
determined, it may be necessary to scan from below 25 Daltons to measure
the peaks in the 26-35 Dalton range for reliable identification.
5.3.4 GC/MS interface--Any GC to MS interface that meets all
performance requirements in this method may be used.
5.3.5 Data system--A computer system must be interfaced to the mass
spectrometer that allows continuous acquisition and storage of mass
spectra throughout the chromatographic program. The computer must have
software that allows searching any GC/MS data file for specific m/z's
(masses) and plotting m/z abundances versus time or scan number. This
type of plot is defined as an extracted ion current profile (EICP).
Software must also be available that allows integrating the abundance at
any EICP between specified time or scan number limits.
5.4 Syringes--Graduated, 5-25 mL, glass hypodermic with Luerlok tip,
compatible with the purging device.
5.5 Micro syringes--Graduated, 25-1000 [micro]L, with 0.006 in. ID
needle.
5.6 Syringe valve--Two-way, with Luer ends.
5.7 Syringe--5 mL, gas-tight with shut-off valve.
5.8 Bottle--15 mL, screw-cap, with Teflon cap liner.
5.9 Balance--Analytical, capable of accurately weighing 0.0001 g.
6. Reagents
6.1 Reagent water--Reagent water is defined as water in which the
analytes of interest and interfering compounds are not detected at the
MDLs of the analytes of interest. It may be generated by passing
deionized water, distilled water, or tap water through a carbon bed,
passing the water through a water purifier, or heating the water to
between 90 and 100 [deg]C while bubbling contaminant-free gas through it
for approximately 1 hour. While still hot, transfer the water to screw-
cap bottles and seal with a fluoropolymer-lined cap.
6.2 Sodium thiosulfate--(ACS) Granular.
6.3 Trap materials.
6.3.1 2,6-Diphenylene oxide polymer--Tenax, 60/80 mesh,
chromatographic grade, or equivalent.
6.3.2 Methyl silicone packing--3% OV-1 on Chromosorb-W, 60/80 mesh,
or equivalent.
6.3.3 Silica gel--35/60 mesh, Davison, Grade-15 or equivalent.
6.3.4 Other trap materials are acceptable if performance
requirements in this method are met.
6.4 Methanol--Demonstrated to be free from the target analytes and
potentially interfering compounds.
6.5 Stock standard solutions--Stock standard solutions may be
prepared from pure materials, or purchased as certified solutions.
Traceability must be to the National Institute of Standards and
Technology (NIST) or other national or international standard, when
available. Stock solution concentrations alternative to those below may
be used. Prepare stock standard solutions in methanol using assayed
liquids or gases as appropriate. Because some of the compounds in this
method are known to be toxic, primary dilutions should be prepared in a
hood, and a NIOSH/MESA approved toxic gas respirator should be worn when
high concentrations of neat materials are handled. The following
procedure may be used to prepare standards from neat materials:
6.5.1 Place about 9.8 mL of methanol in a 10-mL ground-glass-
stoppered volumetric flask. Allow the flask to stand, unstoppered, for
about 10 minutes or until all alcohol wetted surfaces have dried. Weigh
the flask to the nearest 0.1 mg.
6.5.2 Add the assayed reference material.
6.5.2.1 Liquids--Using a 100 [micro]L syringe, immediately add two
or more drops of assayed reference material to the flask. Be sure that
the drops fall directly into the alcohol without contacting the neck of
the flask. Reweigh, dilute to volume, stopper, then mix by inverting the
flask several times. Calculate the concentration in [micro]g/[micro]L
from the net gain in weight.
6.5.2.2 Gases--To prepare standards for any of compounds that boil
below 30 [deg]C, fill a 5-mL valved gas-tight syringe with reference
standard vapor to the 5.0 mL mark. Lower the needle to 5 mm above the
methanol meniscus. Slowly introduce the vapor above the surface of the
liquid (the vapor will rapidly dissolve in the methanol). Reweigh,
dilute to volume, stopper, then mix by inverting the flask several
times. Calculate the concentration in [micro]g/[micro]L from the net
gain in weight.
6.5.3 When compound purity is assayed to be 96% or greater, the
weight may be used without correction to calculate the concentration of
the stock standard. Commercially prepared stock standards may be used at
any concentration if they are certified by the manufacturer or by an
independent source.
6.5.4 Prepare fresh standards weekly for the gases and 2-
chloroethylvinyl ether. Unless stated otherwise in this method, store
non-aqueous standards in fluoropolymer-
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lined screw-cap, or heat-sealed, glass containers, in the dark at -20 to
-10 [deg]C. Store aqueous standards; e.g., the aqueous LCS (section
8.4.1) in the dark at <=6 [deg]C (but do not freeze) with zero
headspace; e.g., in VOA vials (section 5.1.1). Standards prepared by the
laboratory may be stored for up to one month, except when comparison
with QC check standards indicates that a standard has degraded or become
more concentrated due to evaporation, or unless the laboratory has data
on file to prove stability for a longer period. Commercially prepared
standards may be stored until the expiration date provided by the
vendor, except when comparison with QC check standards indicates that a
standard has degraded or become more concentrated due to evaporation, or
unless the laboratory has data from the vendor on file to prove
stability for a longer period.
Note: 2-Chloroethylvinyl ether has been shown to be stable for as
long as one month if prepared as a separate standard, and the other
analytes have been shown to be stable for as long as 2 months if stored
at less than -10 [deg]C with minimal headspace in sealed, miniature
inert-valved vials.
6.6 Secondary dilution standards--Using stock solutions, prepare
secondary dilution standards in methanol that contain the compounds of
interest, either singly or mixed. Secondary dilution standards should be
prepared at concentrations such that the aqueous calibration standards
prepared in section 7.3.2 will bracket the working range of the
analytical system.
6.7 Surrogate standard spiking solution--Select a minimum of three
surrogate compounds from Table 5. The surrogates selected should match
the purging characteristics of the analytes of interest as closely as
possible. Prepare a stock standard solution for each surrogate in
methanol as described in section 6.5, and prepare a solution for spiking
the surrogates into all blanks, LCSs, and MS/MSDs. Prepare the spiking
solution such that spiking a small volume will result in a constant
concentration of the surrogates. For example, add 10 [micro]L of a
spiking solution containing the surrogates at a concentration of 15
[micro]g/mL in methanol to a 5-mL aliquot of water to produce a
concentration of 30 [micro]g/L for each surrogate. Other surrogate
concentrations may be used. Store per section 6.5.4.
6.8 BFB standard--Prepare a solution of BFB in methanol as described
in Sections 6.5 and 6.6. The solution should be prepared such that an
injection or purging from water will result in introduction of <= 50 ng
into the GC. BFB may be included in a mixture with the internal
standards and/or surrogates.
6.9 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Assemble a purge-and-trap system that meets the specifications
in Section 5.2. Prior to first use, condition the trap overnight at 180
[deg]C by backflushing with gas at a flow rate of at least 20 mL/min.
Condition the trap after each analysis at a temperature and time
sufficient to prevent detectable concentrations of the analytes or
contaminants in successive analyses.
7.2 Connect the purge-and-trap system to the gas chromatograph. The
gas chromatograph should be operated using temperature and flow rate
conditions equivalent to those given in the footnotes to Table 3.
Alternative temperature and flow rate conditions may be used provided
that performance requirements in this method are met.
7.3 Internal standard calibration.
7.3.1 Internal standards.
7.3.1.1 Select three or more internal standards similar in
chromatographic behavior to the compounds of interest. Suggested
internal standards are listed in Table 5. Use the base peak m/z as the
primary m/z for quantification of the standards. If interferences are
found at the base peak, use one of the next two most intense m/z's for
quantitation. Demonstrate that measurements of the internal standards
are not affected by method or matrix interferences.
7.3.1.2 To assure accurate analyte identification, particularly when
selected ion monitoring (SIM) is used, it may be advantageous to include
more internal standards than those suggested in Section 7.3.1.1. An
analyte will be located most accurately if its retention time relative
to an internal standard is in the range of 0.8 to 1.2.
7.3.1.3 Prepare a stock standard solution for each internal standard
in methanol as described in Section 6.5, and prepare a solution for
spiking the internal standards into all blanks, LCSs, and MS/MSDs.
Prepare the spiking solution such that spiking a small volume will
result in a constant concentration of the internal standards. For
example, add 10 [micro]L of a spiking solution containing the internal
standards at a concentration of 15 [micro]g/mL in methanol to a 5-mL
aliquot of water to produce a concentration of 30 [micro]g/L for each
internal standard. Other concentrations may be used. The internal
standard solution and the surrogate standard spiking solution (Section
6.7) may be combined, if desired. Store per section 6.5.4.
7.3.2 Calibration.
7.3.2.1 Calibration standards.
7.3.2.1.1 Prepare calibration standards at a minimum of five
concentration levels for each analyte of interest by adding appropriate
volumes of one or more stock standards to a fixed volume (e.g., 40 mL)
of reagent water in volumetric glassware. Fewer levels may be necessary
for some analytes based on the sensitivity of the MS, but no
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fewer than 3 levels may be used, and only the highest or lowest point(s)
may be dropped from the calibration. One of the calibration standards
should be at a concentration at or below the ML or as specified by a
regulatory/control authority or in a permit. The ML value may be rounded
to a whole number that is more convenient for preparing the standard,
but must not exceed the ML values listed in Table 1 for those analytes
which list ML values. Alternatively, the laboratory may establish the ML
for each analyte based on the concentration of the lowest calibration
standard in a series of standards produced in the laboratory or obtained
from a commercial vendor, again, provided that the ML value does not
exceed the MLs in Table 1, and provided that the resulting calibration
meets the acceptance criteria in Section 7.3.4, based on the RSD, RSE,
or R\2\. The concentrations of the higher standards should correspond to
the expected range of concentrations found in real samples, or should
define the working range of the GC/MS system for full-scan and/or SIM
operation, as appropriate. A minimum of six concentration levels is
required for a second order, non-linear (e.g., quadratic; ax\2\ + bx + c
= 0) calibration. Calibrations higher than second order are not allowed.
7.3.2.1.2 To each calibration standard or standard mixture, add a
known constant volume of the internal standard spiking solution (section
7.3.1.3) and surrogate standard spiking solution (section 6.7) or the
combined internal standard solution and surrogate spiking solution
(section 7.3.1.3). Aqueous standards may be stored up to 24 hours, if
held in sealed vials with zero headspace. If not so stored, they must be
discarded after one hour.
7.3.2.2 Prior to analysis of the calibration standards, analyze the
BFB standard (section 6.8) and adjust the scan rate of the MS to produce
a minimum of 5 mass spectra across the BFB GC peak, but do not exceed 2
seconds per scan. Adjust instrument conditions until the BFB criteria in
Table 4 are met. Once the scan conditions are established, they must be
used for analyses of all standards, blanks, and samples.
Note: The BFB spectrum may be evaluated by summing the intensities
of the m/z's across the GC peak, subtracting the background at each m/z
in a region of the chromatogram within 20 scans of but not including any
part of the BFB peak. The BFB spectrum may also be evaluated by fitting
a Gaussian to each m/z and using the intensity at the maximum for each
Gaussian, or by integrating the area at each m/z and using the
integrated areas. Other means may be used for evaluation of the BFB
spectrum so long as the spectrum is not distorted to meet the criteria
in Table 4.
7.3.2.3 Analyze the mid-point standard and enter or review the
retention time, relative retention time, mass spectrum, and quantitation
m/z in the data system for each analyte of interest, surrogate, and
internal standard. If additional analytes (Table 2) are to be
quantified, include these analytes in the standard. The mass spectrum
for each analyte must be comprised of a minimum of 2 m/z's; 3 to 5 m/z's
assure more reliable analyte identification. Suggested quantitation m/
z's are shown in Table 6 as the primary m/z. For analytes in Table 6
that do not have a secondary m/z, acquire a mass spectrum and enter one
or more secondary m/z's for more reliable identification. If an
interference occurs at the primary m/z, use one of the secondary m/z's
or an alternative m/z. A single m/z only is required for quantitation.
7.3.2.4 For SIM operation, determine the analytes in each
descriptor, the quantitation m/z for each analyte (the quantitation m/z
can be the same as for full-scan operation; Section 7.3.2.3), the dwell
time on each m/z for each analyte, and the beginning and ending
retention time for each descriptor. Analyze the verification standard in
scan mode to verify m/z's and establish retention times for the
analytes. There must be a minimum of two m/z's for each analyte to
assure analyte identification. To maintain sensitivity, the number of m/
z's in a descriptor should be limited. For example, for a descriptor
with 10 m/z's and a chromatographic peak width of 5 sec, a dwell time of
100 ms at each m/z would result in a scan time of 1 second and provide 5
scans across the GC peak. The quantitation m/z will usually be the most
intense peak in the mass spectrum. The quantitation m/z and dwell time
may be optimized for each analyte. The acquisition table used for SIM
must take into account the mass defect (usually less than 0.2 Dalton)
that can occur at each m/z monitored. Refer to the footnotes to Table 3
for establishing operating conditions and to section 7.3.2.2 for
establishing scan conditions.
7.3.2.5 For combined scan and SIM operation, set up the scan
segments and descriptors to meet requirements in sections 7.3.2.2-
7.3.2.4. Analyze unfamiliar samples in the scan mode to assure that the
analytes of interest are determined.
7.3.3 Analyze each calibration standard according to Section 10 and
tabulate the area at the quantitation m/z against concentration for each
analyte of interest, surrogate, and internal standard. Calculate the
response factor (RF) for each compound at each concentration using
Equation 1.
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[GRAPHIC] [TIFF OMITTED] TR28AU17.012
Where:
As = Area of the characteristic m/z for the analyte to be
measured.
Ais = Area of the characteristic m/z for the internal
standard.
Cis = Concentration of the internal standard ([micro]g/L).
Cs = Concentration of the analyte to be measured ([micro]g/
L).
7.3.4 Calculate the mean (average) and relative standard deviation
(RSD) of the response factors. If the RSD is less than 35%, the RF can
be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to fit a linear or
quadratic regression of response ratios, As/Ais,
vs. concentration ratios Cs/Cis. If used, the regression must be
weighted inversely proportional to concentration (1/C). The coefficient
of determination (R\2\) of the weighted regression must be greater than
0.920 (this value roughly corresponds to the RSD limit of 35%).
Alternatively, the relative standard error (Reference 10) may be used as
an acceptance criterion. As with the RSD, the RSE must be less than 35%.
If an RSE less than 35% cannot be achieved for a quadratic regression,
system performance is unacceptable, and the system must be adjusted and
re-calibrated.
Note: Using capillary columns and current instrumentation, it is
quite likely that a laboratory can calibrate the target analytes in this
method and achieve a linearity metric (either RSD or RSE) well below
35%. Therefore, laboratories are permitted to use more stringent
acceptance criteria for calibration than described here, for example, to
harmonize their application of this method with those from other
sources.
7.4 Calibration verification--Because the analytical system is
calibrated by purge of the analytes from water, calibration verification
is performed using the laboratory control sample (LCS). See section 8.4
for requirements for calibration verification using the LCS, and the
Glossary for further definition.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality assurance program. The minimum requirements of this
program consist of an initial demonstration of laboratory capability and
ongoing analysis of spiked samples and blanks to evaluate and document
data quality (40 CFR 136.7). The laboratory must maintain records to
document the quality of data generated. Results of ongoing performance
tests are compared with established QC acceptance criteria to determine
if the results of analyses meet performance requirements of this method.
When results of spiked samples do not meet the QC acceptance criteria in
this method, a quality control check sample (laboratory control sample;
LCS) must be analyzed to confirm that the measurements were performed in
an in-control mode of operation. A laboratory may develop its own
performance criteria (as QC acceptance criteria), provided such criteria
are as or more restrictive than the criteria in this method.
8.1.1 The laboratory must make an initial demonstration of
capability (DOC) to generate acceptable precision and recovery with this
method. This demonstration is detailed in Section 8.2. On a continuing
basis, the laboratory must repeat demonstration of capability (DOC) at
least annually.
8.1.2 In recognition of advances that are occurring in analytical
technology, and to overcome matrix interferences, the laboratory is
permitted certain options (section 1.5 and 40 CFR 136.6(b)) to improve
separations or lower the costs of measurements. These options may
include an alternative purge-and-trap device, and changes in both column
and type of mass spectrometer (see 40 CFR 136.6(b)(4)(xvi)). Alternative
determinative techniques, such as substitution of spectroscopic or
immunoassay techniques, and changes that degrade method performance, are
not allowed. If an analytical technique other than GC/MS is used, that
technique must have a specificity equal to or greater than the
specificity of GC/MS for the analytes of interest. The laboratory is
also encouraged to participate in inter-comparison and performance
evaluation studies (see section 8.8).
8.1.2.1 Each time a modification is made to this method, the
laboratory is required to repeat the procedure in section 8.2. If the
detection limit of the method will be affected by the change, the
laboratory must demonstrate that the MDLs (40 CFR part 136, appendix B)
are lower than one-third the regulatory compliance limit or the MDLs in
this method, whichever are greater. If calibration will be affected by
the change, the instrument must be recalibrated per section 7. Once the
modification is demonstrated to produce results equivalent or superior
to results produced by this method, that modification may be used
routinely thereafter, so long as the other requirements in this method
are met (e.g., matrix spike/matrix spike
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duplicate recovery and relative percent difference).
8.1.2.1.1 If a modification is to be applied to a specific
discharge, the laboratory must prepare and analyze matrix spike/matrix
spike duplicate (MS/MSD) samples (Section 8.3) and LCS samples (section
8.4). The laboratory must include internal standards and surrogates
(section 8.7) in each of the samples. The MS/MSD and LCS samples must be
fortified with the analytes of interest (section 1.3.). If the
modification is for nationwide use, MS/MSD samples must be prepared from
a minimum of nine different discharges (See section 8.1.2.1.2), and all
QC acceptance criteria in this method must be met. This evaluation only
needs to be performed once, other than for the routine QC required by
this method (for example it could be performed by the vendor of the
alternative materials) but any laboratory using that specific material
must have the results of the study available. This includes a full data
package with the raw data that will allow an independent reviewer to
verify each determination and calculation performed by the laboratory
(see section 8.1.2.2.5, items (a)-(l)).
8.1.2.1.2 Sample matrices on which MS/MSD tests must be performed
for nationwide use of an allowed modification:
(a) Effluent from a publicly owned treatment works (POTW).
(b) ASTM D5905 Standard Specification for Substitute Wastewater.
(c) Sewage sludge, if sewage sludge will be in the permit.
(d) ASTM D1141 Standard Specification for Substitute Ocean Water, if
ocean water will be in the permit.
(e) Untreated and treated wastewaters up to a total of nine matrix
types (see https://www.epa.gov/eg/industrial-effluent-guidelines for a
list of industrial categories with existing effluent guidelines).
(i) At least one of the above wastewater matrix types must have at
least one of the following characteristics:
(A) Total suspended solids greater than 40 mg/L.
(B) Total dissolved solids greater than 100 mg/L.
(C) Oil and grease greater than 20 mg/L.
(D) NaCl greater than 120 mg/L.
(E) CaCO3 greater than 140 mg/L.
(ii) Results of MS/MSD tests must meet QC acceptance criteria in
section 8.3.
(f) A proficiency testing (PT) sample from a recognized provider, in
addition to tests of the nine matrices (section 8.1.2.1.1).
8.1.2.2 The laboratory is required to maintain records of
modifications made to this method. These records include the following,
at a minimum:
8.1.2.2.1 The names, titles, and business street addresses,
telephone numbers, and email addresses of the analyst(s) that performed
the analyses and modification, and of the quality control officer that
witnessed and will verify the analyses and modifications.
8.1.2.2.2 A list of analytes, by name and CAS Registry Number.
8.1.2.2.3 A narrative stating reason(s) for the modifications.
8.1.2.2.4 Results from all quality control (QC) tests comparing the
modified method to this method, including:
(a) Calibration (section 7).
(b) Calibration verification/LCS (section 8.4).
(c) Initial demonstration of capability (section 8.2).
(d) Analysis of blanks (section 8.5).
(e) Matrix spike/matrix spike duplicate analysis (section 8.3).
(f) Laboratory control sample analysis (section 8.4).
8.1.2.2.5 Data that will allow an independent reviewer to validate
each determination by tracing the instrument output (peak height, area,
or other signal) to the final result. These data are to include:
(a) Sample numbers and other identifiers.
(b) Analysis dates and times.
(c) Analysis sequence/run chronology.
(d) Sample volume (Section 10).
(e) Sample dilution (Section 13.2).
(f) Instrument and operating conditions.
(g) Column (dimensions, material, etc).
(h) Operating conditions (temperature program, flow rate, etc).
(i) Detector (type, operating conditions, etc).
(j) Chromatograms, mass spectra, and other recordings of raw data.
(k) Quantitation reports, data system outputs, and other data to
link the raw data to the results reported.
(l) A written Standard Operating Procedure (SOP).
8.1.2.2.6 Each individual laboratory wishing to use a given
modification must perform the start-up tests in section 8.1.2 (e.g.,
DOC, MDL), with the modification as an integral part of this method
prior to applying the modification to specific discharges. Results of
the DOC must meet the QC acceptance criteria in Table 7 for the analytes
of interest (section 1.3), and the MDLs must be equal to or lower than
the MDLs in Table3 for the analytes of interest
8.1.3 Before analyzing samples, the laboratory must analyze a blank
to demonstrate that interferences from the analytical system, labware,
and reagents are under control. Each time a batch of samples is analyzed
or reagents are changed, a blank must be analyzed as a safeguard against
laboratory contamination. Requirements for the blank are given in
section 8.5.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze
samples to monitor
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and evaluate method and laboratory performance on the sample matrix. The
procedure for spiking and analysis is given in section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
analysis of a quality control check sample (laboratory control sample,
LCS; on-going precision and recovery sample, OPR) that the measurement
system is in control. This procedure is given in section 8.4.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is given in
section 8.8.
8.1.7 The large number of analytes tested in performance tests in
this method present a substantial probability that one or more will fail
acceptance criteria when many analytes are tested simultaneously, and a
re-test is allowed if this situation should occur. If, however,
continued re-testing results in further repeated failures, the
laboratory must document and report the failures (e.g., as qualifiers on
results), unless the failures are not required to be reported as
determined by the regulatory/control authority. Results associated with
a QC failure for an analyte regulated in a discharge cannot be used to
demonstrate regulatory compliance. QC failures do not relieve a
discharger or permittee of reporting timely results.
8.2 Initial demonstration of capability (DOC)--To establish the
ability to generate acceptable recovery and precision, the laboratory
must perform the DOC in sections 8.2.1 through 8.2.6 for the analytes of
interest. The laboratory must also establish MDLs for the analytes of
interest using the MDL procedure at 40 CFR part 136, appendix B. The
laboratory's MDLs must be equal to or lower than those listed in Table 1
for those analytes which list MDL values, or lower than one-third the
regulatory compliance limit, whichever is greater. For MDLs not listed
in Table 1, the laboratory must determine the MDLs using the MDL
procedure at 40 CFR part 136, appendix B under the same conditions used
to determine the MDLs for the analytes listed in Table 1. All procedures
used in the analysis must be included in the DOC.
8.2.1 For the DOC, a QC check sample concentrate (LCS concentrate)
containing each analyte of interest (section 1.3) is prepared in
methanol. The QC check sample concentrate must be prepared independently
from those used for calibration, but may be from the same source as the
second-source standard used for calibration verification/LCS (sections
7.4 and 8.4). The concentrate should produce concentrations of the
analytes of interest in water at the mid-point of the calibration range,
and may be at the same concentration as the LCS (section 8.4).
Note: QC check sample concentrates are no longer available from EPA.
8.2.2 Using a pipet or micro-syringe, prepare four LCSs by adding an
appropriate volume of the concentrate to each of four aliquots of
reagent water. The volume of reagent water must be the same as the
volume that will be used for the sample, blank (section 8.5), and MS/MSD
(section 8.3). A volume of 5 mL and a concentration of 20 [micro]g/L
were used to develop the QC acceptance criteria in Table 7. An
alternative volume and sample concentration may be used, provided that
all QC tests are performed and all QC acceptance criteria in this method
are met. Also add an aliquot of the surrogate spiking solution (section
6.7) and internal standard spiking solution (section 7.3.1.3) to the
reagent-water aliquots.
8.2.3 Analyze the four LCSs according to the method beginning in
section 10.
8.2.4 Calculate the average percent recovery (X) and the standard
deviation of the percent recovery (s) for each analyte using the four
results.
8.2.5 For each analyte, compare s and X with the corresponding
acceptance criteria for precision and recovery in Table 7. For analytes
in Tables 1 and 2 not listed in Table 7, DOC QC acceptance criteria must
be developed by the laboratory. EPA has provided guidance for
development of QC acceptance criteria (References 11 and 12).
Alternatively, acceptance criteria for analytes not listed in Table 7
may be based on laboratory control charts. If s and X for all analytes
of interest meet the acceptance criteria, system performance is
acceptable and analysis of blanks and samples may begin. If any
individual s exceeds the precision limit or any individual X falls
outside the range for recovery, system performance is unacceptable for
that analyte.
Note: The large number of analytes in Tables 1 and 2 present a
substantial probability that one or more will fail at least one of the
acceptance criteria when many or all analytes are determined
simultaneously. Therefore, the analyst is permitted to conduct a ``re-
test'' as described in section 8.2.6.
8.2.6 When one or more of the analytes tested fail at least one of
the acceptance criteria, repeat the test for only the analytes that
failed. If results for these analytes pass, system performance is
acceptable and analysis of samples and blanks may proceed. If one or
more of the analytes again fail, system performance is unacceptable for
the analytes that failed the acceptance criteria. Correct the problem
and repeat the test (section 8.2). See section 8.1.7 for disposition of
repeated failures.
Note: To maintain the validity of the test and re-test, system
maintenance and/or adjustment is not permitted between this pair of
tests.
8.3 Matrix spike and matrix spike duplicate (MS/MSD)--The purpose of
the MS/MSD
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requirement is to provide data that demonstrate the effectiveness of the
method as applied to the samples in question by a given laboratory, and
both the data user (discharger, permittee, regulated entity, regulatory/
control authority, customer, other) and the laboratory share
responsibility for provision of such data. The data user should identify
the sample and the analytes of interest (section 1.3) to be spiked and
provide sufficient sample volume to perform MS/MSD analyses. The
laboratory must, on an ongoing basis, spike at least 5% of the samples
in duplicate from each discharge being monitored to assess accuracy
(recovery and precision). If direction cannot be obtained from the data
user, the laboratory must spike at least one sample in duplicate per
extraction batch of up to 20 samples with the analytes in Table 1.
Spiked sample results should be reported only to the data user whose
sample was spiked, or as requested or required by a regulatory/control
authority, or in a permit.
8.3.1 If, as in compliance monitoring, the concentration of a
specific analyte will be checked against a regulatory concentration
limit, the concentration of the spike should be at that limit;
otherwise, the concentration of the spike should be one to five times
higher than the background concentration determined in section 8.3.2, at
or near the mid-point of the calibration range, or at the concentration
in the LCS (section 8.4) whichever concentration would be larger.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of the each analyte of interest. If necessary, prepare
a new check sample concentrate (section 8.2.1) appropriate for the
background concentration. Spike and analyze two additional sample
aliquots, and determine the concentration after spiking (A1
and A2) of each analyte. Calculate the percent recoveries
(P1 and P2) as 100 (A1-B)/T and 100
(A2-B)/T, where T is the known true value of the spike. Also
calculate the relative percent difference (RPD) between the
concentrations (A1 and A2) as 200
A1-A2/(A1 +
A2). If necessary, adjust the concentrations used to
calculate the RPD to account for differences in the volumes of the
spiked aliquots.
8.3.3 Compare the percent recoveries (P1 and
P2) and the RPD for each analyte in the MS/MSD aliquots with
the corresponding QC acceptance criteria in Table 7. A laboratory may
develop and apply QC acceptance criteria more restrictive than the
criteria in Table 7, if desired.
8.3.3.1 If any individual P falls outside the designated range for
recovery in either aliquot, or the RPD limit is exceeded, the result for
the analyte in the unspiked sample is suspect. See Section 8.1.7 for
disposition of failures.
8.3.3.2 The acceptance criteria in Table 7 were calculated to
include an allowance for error in measurement of both the background and
spike concentrations, assuming a spike to background ratio of 5:1. This
error will be accounted for to the extent that the spike to background
ratio approaches 5:1 (Reference 13) and is applied to spike
concentrations of 20 [micro]g/L and higher. If spiking is performed at a
concentration lower than 20 [micro]g/L, the laboratory must use the QC
acceptance criteria in Table 7, the optional QC acceptance criteria
calculated for the specific spike concentration in Table 8, or optional
in-house criteria (Section 8.3.4). To use the acceptance criteria in
Table 8: (1) Calculate recovery (X') using the equation in Table 8,
substituting the spike concentration (T) for C; (2) Calculate overall
precision (S') using the equation in Table 8, substituting X' for X; (3)
Calculate the range for recovery at the spike concentration as (100 X'/
T) 2.44(100 S'/T)% (Reference 4). For analytes of
interest in Tables 1 and 2 not listed in Table 7, QC acceptance criteria
must be developed by the laboratory. EPA has provided guidance for
development of QC acceptance criteria (References 11 and 12).
Alternatively, acceptance criteria may be based on laboratory control
charts. In-house LCS QC acceptance criteria must be updated at least
every two years.
8.3.4 After analysis of a minimum of 20 MS/MSD samples for each
target analyte and surrogate, and if the laboratory chooses to develop
and apply in-house QC limits, the laboratory should calculate and apply
in-house QC limits for recovery and RPD of future MS/MSD samples
(section 8.3). The QC limits for recovery are calculated as the mean
observed recovery 3 standard deviations, and the
upper QC limit for RPD is calculated as the mean RPD plus 3 standard
deviations of the RPDs. The in-house QC limits must be updated at least
every two years and re-established after any major change in the
analytical instrumentation or process. If in-house QC limits are
developed, at least 80% of the analytes tested in the MS/MSD must have
in-house QC acceptance criteria that are tighter than those in Table 7
and the remaining analytes (those other than the analytes included in
the 80%) must meet the acceptance criteria in Table 7. If an in-house QC
limit for the RPD is greater than the limit in Table 7, then the limit
in Table 7 must be used. Similarly, if an in-house lower limit for
recovery is below the lower limit in Table 7, then the lower limit in
Table 7 must be used, and if an in-house upper limit for recovery is
above the upper limit in Table 7, then the upper limit in Table 7 must
be used.
8.4 Calibration verification/laboratory control sample (LCS)--The
working calibration curve or RF must be verified immediately after
calibration and at the beginning of each 12-hour shift by the
measurement of an LCS. The LCS must be from a source different from the
source used for
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calibration (section 7.3.2.1), but may be the same as the sample
prepared for the DOC (section 8.2.1).
Note: The 12-hour shift begins after analysis of BFB, the LCS, and
the blank, and ends 12 hours later. BFB, the LCS, and blank are outside
of the 12-hour shift (Section 11.4). The MS and MSD are treated as
samples and are analyzed within the 12-hour shift.
8.4.1 Prepare the LCS by adding QC check sample concentrate (section
8.2.1) to reagent water. Include all analytes of interest (Section 1.3)
in the LCS. The volume of reagent water must be the same as the volume
used for the sample, blank (Section 8.5), and MS/MSD (section 8.3). Also
add an aliquot of the surrogate solution (Section 6.7) and internal
standard solution (section 7.3.1.3). The concentration of the analytes
in reagent water should be the same as the concentration in the DOC
(section 8.2.2).
8.4.2 Analyze the LCS prior to analysis of field samples in the
batch of samples analyzed during the 12-hour shift (see the Note at
section 8.4). Determine the concentration (A) of each analyte. Calculate
the percent recovery (Q) as 100 (A/T) %, where T is the true value of
the concentration in the LCS.
8.4.3 Compare the percent recovery (Q) for each analyte with its
corresponding QC acceptance criterion in Table 7. For analytes of
interest in Tables 1 and 2 not listed in Table 7, use the QC acceptance
criteria developed for the LCS (section 8.4.5). If the recoveries for
all analytes of interest fall within their respective QC acceptance
criteria, analysis of blanks and field samples may proceed. If any
individual Q falls outside the range, proceed according to section
8.4.4.
Note: The large number of analytes in Tables 1--2 present a
substantial probability that one or more will fail the acceptance
criteria when all analytes are tested simultaneously. Because a re-test
is allowed in event of failure (sections 8.1.7 and 8.4.3), it may be
prudent to analyze two LCSs together and evaluate results of the second
analysis against the QC acceptance criteria only if an analyte fails the
first test.
8.4.4 Repeat the test only for those analytes that failed to meet
the acceptance criteria (Q). If these analytes now pass, system
performance is acceptable and analysis of blanks and samples may
proceed. Repeated failure, however, will confirm a general problem with
the measurement system. If this occurs, repeat the test (section 8.4.2).
using a fresh LCS (section 8.2.2) or an LCS prepared with a fresh QC
check sample concentrate (section 8.2.1), or perform and document system
repair. Subsequent to repair, repeat the calibration verification/LCS
test (section 8.4). If the acceptance criteria for Q cannot be met, re-
calibrate the instrument (section 7). See section 8.1.7 for disposition
of repeated failures.
Note: To maintain the validity of the test and re-test, system
maintenance and/or adjustment is not permitted between the pair of
tests.
8.4.5 After analysis of 20 LCS samples, and if the laboratory
chooses to develop and apply in-house QC limits, the laboratory should
calculate and apply in-house QC limits for recovery to future LCS
samples (section 8.4). Limits for recovery in the LCS calculated as the
mean recovery 3 standard deviations. A minimum of
80% of the analytes tested for in the LCS must have QC acceptance
criteria tighter than those in Table 7, and the remaining analytes
(those other than the analytes included in the 80%) must meet the
acceptance criteria in Table 7. If an in-house lower limit for recovery
is lower than the lower limit in Table 7, the lower limit in Table 7
must be used, and if an in-house upper limit for recovery is higher than
the upper limit in Table 7, the upper limit in Table 7 must be used.
Many of the analytes and surrogates do not have acceptance criteria. The
laboratory should use 60-140% as interim acceptance criteria for
recoveries of spiked analytes that do not have recovery limits specified
in Table 7, and least 80% of the analytes should meet the 60-140%
interim criteria until in-house LCS limits are developed. Alternatively,
acceptance criteria for analytes that do not have recovery limits in
Table 7 may be based on laboratory control charts. In-house QC
acceptance criteria must be updated at least every two years.
8.5 Blank--A blank must be analyzed prior to each 12-hour shift to
demonstrate freedom from contamination. A blank must also be analyzed
after a sample containing a high concentration of an analyte or
potentially interfering compound to demonstrate freedom from carry-over.
8.5.1 Spike the internal standards and surrogates into the blank.
Analyze the blank immediately after analysis of the LCS (Section 8.4)
and prior to analysis of the MS/MSD and samples to demonstrate freedom
from contamination.
8.5.2 If any analyte of interest is found in the blank: At a
concentration greater than the MDL for the analyte, at a concentration
greater than one-third the regulatory compliance limit, or at a
concentration greater than one-tenth the concentration in a sample
analyzed during the 12-hour shift (section 8.4), whichever is greater;
analysis of samples must be halted and samples affected by the blank
must be re-analyzed. If, however, continued re-testing results in
repeated blank contamination, the laboratory must document and report
the failures (e.g., as qualifiers on results), unless the failures are
not required to be reported as determined by the regulatory/control
authority. Results associated with blank contamination for an analyte
regulated in a discharge cannot be used to demonstrate regulatory
compliance.
[[Page 257]]
QC failures do not relieve a discharger or permittee of reporting timely
results.
8.6 Surrogate recoveries--The laboratory must evaluate surrogate
recovery data in each sample against its in-house surrogate recovery
limits for surrogates that do not have acceptance criteria in Table 7.
The laboratory may use 60-140% as interim acceptance criteria for
recoveries for surrogates not listed in Table 5. At least 80% of the
surrogates must meet the 60-140% interim criteria until in-house limits
are developed. Alternatively, surrogate recovery limits may be developed
from laboratory control charts.
8.6.1 Spike the surrogates into all samples, blanks, LCSs, and MS/
MSDs. Compare surrogate recoveries against the QC acceptance criteria in
Table 7. For surrogates in Table 5 without QC acceptance criteria in
Table 7, and for other surrogates that may be used by the laboratory,
limits must be developed by the laboratory. EPA has provided guidance
for development of QC acceptance criteria (References 11 and 12).
Alternatively, surrogate recovery limits may be developed from
laboratory control charts. In-house QC acceptance criteria must be
updated at least every two years.
8.6.2 If any recovery fails its criteria, attempt to find and
correct the cause of the failure. See section 8.1.7 for disposition of
failures.
8.7 Internal standard responses.
8.7.1 Calibration verification/LCS--The responses (GC peak heights
or areas) of the internal standards in the calibration verification/LCS
must be within 50% to 200% (1/2 to 2x) of their respective responses in
the mid-point calibration standard. If they are not, repeat the LCS test
using a fresh QC check sample (section 8.4.1) or perform and document
system repair. Subsequent to repair, repeat the calibration
verification/LCS test (section 8.4). If the responses are still not
within 50% to 200%, re-calibrate the instrument (section 7) and repeat
the calibration verification/LCS test.
8.7.2 Samples, blanks, and MS/MSDs--The responses (GC peak heights
or areas) of each internal standard in each sample, blank, and MS/MSD
must be within 50% to 200% (1/2 to 2x) of its respective response in the
mid-point calibration standard. If, as a group, all internal standards
are not within this range, perform and document system repair, repeat
the calibration verification/LCS test (section 8.4), and re-analyze the
affected samples. If a single internal standard is not within the 50% to
200% range, use an alternative internal standard for quantitation of the
analyte referenced to the affected internal standard. It may be
necessary to use the data system to calculate a new response factor from
calibration data for the alternative internal standard/analyte pair. If
an internal standard fails the 50-200% criteria and no analytes are
detected in the sample, ignore the failure or report it if required by
the regulatory/control authority.
8.8 As part of the QC program for the laboratory, control charts or
statements of accuracy for wastewater samples must be assessed and
records maintained periodically (see 40 CFR 136.7(c)(1)(viii)). After
analysis of five or more spiked wastewater samples as in section 8.3,
calculate the average percent recovery (PX) and the standard
deviation of the percent recovery (sp). Express the accuracy assessment
as a percent interval from PX-2sp to PX
+ 2sp. For example, if PX = 90% and sp = 10%, the
accuracy interval is expressed as 70-110%. Update the accuracy
assessment for each analyte on a regular basis (e.g., after each 5-10
new accuracy measurements). If desired, statements of accuracy for
laboratory performance, independent of performance on samples, may be
developed using LCSs.
8.9 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of environmental measurements. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevant performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Collect the sample as a grab sample in a glass container having
a total volume of at least 25 mL. Fill the sample bottle just to
overflowing in such a manner that no air bubbles pass through the sample
as the bottle is being filled. Seal the bottle so that no air bubbles
are entrapped in it. If needed, collect additional sample(s) for the MS/
MSD (section 8.3).
9.2 Ice or refrigerate samples at <=6 [deg]C from the time of
collection until analysis, but do not freeze. If residual chlorine is
present, add sodium thiosulfate preservative (10 mg/40 mL is sufficient
for up to 5 ppm Cl2) to the empty sample bottle just prior to
shipping to the sampling site. Any method suitable for field use may be
employed to test for residual chlorine (Reference 14). Field test kits
are also available for this purpose. If sodium thiosulfate interferes in
the determination of the analytes, an alternative preservative (e.g.,
ascorbic acid or sodium sulfite) may be used. If preservative has been
added, shake the sample vigorously for one minute. Maintain the hermetic
seal on the sample bottle until time of analysis.
9.3 If acrolein is to be determined, analyze the sample within 3
days. To extend the holding time to 14 days, acidify a separate sample
to pH 4-5 with HCl using the procedure in section 9.7.
9.4 Experimental evidence indicates that some aromatic compounds,
notably benzene,
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toluene, and ethyl benzene are susceptible to rapid biological
degradation under certain environmental conditions (Reference 3).
Refrigeration alone may not be adequate to preserve these compounds in
wastewaters for more than seven days. To extend the holding time for
aromatic compounds to 14 days, acidify the sample to approximately pH 2
using the procedure in section 9.7.
9.5 If halocarbons are to be determined, either use the acidified
aromatics sample in section 9.4 or acidify a separate sample to a pH of
about 2 using the procedure in section 9.7.
9.6 The ethers listed in Table 2 are prone to hydrolysis at pH 2
when a heated purge is used. Aqueous samples should not be acid
preserved if these ethers are of interest, or if the alcohols they would
form upon hydrolysis are of interest and the ethers are anticipated to
present.
9.7 Sample acidification--Collect about 500 mL of sample in a clean
container and adjust the pH of the sample to 4-5 for acrolein (section
9.3), or to about 2 for the aromatic compounds (section 9.4) by adding
1+1 HCl while swirling or stirring. Check the pH with narrow range pH
paper. Fill a sample container as described in section 9.1.
Alternatively, fill a precleaned vial (section 5.1.1) that contains
approximately 0.25 mL of 1+1 HCl with sample as in section 9.1. If
preserved using this alternative procedure, the pH of the sample can be
verified to be <2 after some of the sample is removed for analysis.
Acidification will destroy 2-chloroethylvinyl ether; therefore,
determine 2-chloroethylvinyl ether from the unacidified sample.
9.8 All samples must be analyzed within 14 days of collection
(Reference 3), unless specified otherwise in sections 9.3-9.7.
10. Sample Purging and Gas Chromatography
10.1 The footnote to Table 3 gives the suggested GC column and
operating conditions MDLs and MLs for many of the analytes are given in
Table 1. Retention times for many of the analytes are given in Table 3.
Sections 10.2 through 10.7 suggest procedures that may be used with a
manual purge-and-trap system. Auto-samplers and other columns or
chromatographic conditions may be used if requirements in this method
are met. Prior to performing analyses, and between analyses, it may be
necessary to bake the purge-and-trap and GC systems (section 3.3).
10.2 Attach the trap inlet to the purging device, and set the purge-
and-trap system to purge. Open the syringe valve located on the purging
device sample introduction needle.
10.3 Allow the sample to come to ambient temperature prior to
pouring an aliquot into the syringe. Remove the plunger from a syringe
and attach a closed syringe valve. Open the sample bottle (or standard)
and carefully pour the sample into the syringe barrel to just short of
overflowing. Replace the syringe plunger and compress the sample. Open
the syringe valve and vent any residual air while adjusting the sample
volume. Since this process of taking an aliquot destroys the validity of
the sample for future analysis, the analyst should fill a second syringe
at this time to protect against possible loss of data. Add the surrogate
spiking solution (section 6.7) and internal standard spiking solution
(section 7.3.1.3) through the valve bore, then close the valve. The
surrogate and internal standards may be mixed and added as a single
spiking solution. Autosamplers designed for purge-and-trap analysis of
volatiles also may be used.
10.4 Attach the syringe valve assembly to the syringe valve on the
purging device. Open the syringe valve and inject the sample into the
purging chamber.
10.5 Close both valves and purge the sample at a temperature, flow
rate, and duration sufficient to purge the less-volatile analytes onto
the trap, yet short enough to prevent blowing the more-volatile analytes
through the trap. The temperature, flow rate, and time should be
determined by test. The same purge temperature, flow rate, and purge
time must be used for all calibration, QC, and field samples.
10.6 After the purge, set the purge-and-trap system to the desorb
mode, and begin the temperature program of the gas chromatograph.
Introduce the trapped materials to the GC column by rapidly heating the
trap to the desorb temperature while backflushing the trap with carrier
gas at the flow rate and for the time necessary to desorb the analytes
of interest. The optimum temperature, flow rate, and time should be
determined by test. The same temperature, desorb time, and flow rate
must be used for all calibration, QC, and field samples. If heating of
the trap does not result in sharp peaks for the early eluting analytes,
the GC column may be used as a secondary trap by cooling to an ambient
or subambient temperature. To avoid carry-over and interferences,
maintain the trap at the desorb temperature and flow rate until the
analytes, interfering compounds, and excess water are desorbed. The
optimum conditions should be determined by test.
10.7 Start MS data acquisition at the start of the desorb cycle and
stop data collection when the analytes of interest, potentially
interfering compounds, and water have eluted (see the footnote to Table
3 for conditions).
10.8 Cool the trap to the purge temperature and return the trap to
the purge mode. When the trap is cool, the next sample can be analyzed.
11. Performance Tests
11.1 At the beginning of each 12-hour shift during which standards
or samples will be
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analyzed, perform the tests in sections 11.2-11.3 to verify system
performance. Use the instrument operating conditions in the footnotes to
Table 3 for these performance tests. Alternative conditions may be used
so as long as all QC requirements are met.
11.2 BFB--Inject 50 ng of BFB solution directly on the column.
Alternatively, add BFB to reagent water or an aqueous standard such that
50 ng or less of BFB will be introduced into the GC. Analyze according
to section 10. Confirm that all criteria in section 7.3.2.2 and Table 4
are met. If all criteria are not met, perform system repair, retune the
mass spectrometer, and repeat the test until all criteria are met.
11.3 Verify calibration with the LCS (section 8.4) after the
criteria for BFB are met (Reference 15) and prior to analysis of a blank
or sample. After verification, analyze a blank (section 8.5) to
demonstrate freedom from contamination and carry-over at the MDL. Tests
for BFB, the LCS, and the blank are outside of the 12-hour shift, and
the 12-hour shift includes samples and matrix spikes and matrix spike
duplicates (section 8.4). The total time for analysis of BFB, the LCS,
the blank, and the 12-hour shift must not exceed 14 hours.
12. Qualitative Identification
12.1 Identification is accomplished by comparison of results from
analysis of a sample or blank with data stored in the GC/MS data system
(section 7.3.2.3). Identification of an analyte is confirmed per
sections 12.1.1 through 12.1.4.
12.1.1 The signals for the quantitation and secondary m/z's stored
in the data system (section 7.3.2.3) for each analyte of interest must
be present and must maximize within the same two consecutive scans.
12.1.2 The retention time for the analyte should be within 10 seconds of the analyte in the LCS run at the
beginning of the shift (section 8.4).
Note: Retention time windows other than 10
seconds may be appropriate depending on the performance of the gas
chromatograph or observed retention time drifts due to certain types of
matrix effects. Relative retention time (RRT) may be used as an
alternative to absolute retention times if retention time drift is a
concern. RRT is a unitless quantity (see section 20.2), although some
procedures refer to ``RRT units'' in providing the specification for the
agreement between the RRT values in the sample and the LCS or other
standard. When significant retention time drifts are observed, dilutions
or spiked samples may help the analyst determine the effects of the
matrix on elution of the target analytes and to assist in qualitative
identification.
12.1.3 Either the background corrected EICP areas, or the corrected
relative intensities of the mass spectral peaks at the GC peak maximum,
must agree within 50% to 200% (\1/2\ to 2 times) for the quantitation
and secondary m/z's in the reference mass spectrum stored in the data
system (section 7.3.2.3), or from a reference library. For example, if a
peak has an intensity of 20% relative to the base peak, the analyte is
identified if the intensity of the peak in the sample is in the range of
10% to 40% of the base peak.
12.1.4 If the acquired mass spectrum is contaminated, or if
identification is ambiguous, an experienced spectrometrist (section 1.6)
must determine the presence or absence of the compound.
12.2 Structural isomers that produce very similar mass spectra
should be identified as individual isomers if they have sufficiently
different gas chromatographic retention times. Sufficient gas
chromatographic resolution is achieved if the height of the valley
between two isomer peaks is less than 50% of the average of the two peak
heights. Otherwise, structural isomers are identified as isomeric pairs.
The resolution should be verified on the mid-point concentration of the
initial calibration as well as the laboratory designated continuing
calibration verification level if closely eluting isomers are to be
reported.
13. Calculations
13.1 When an analyte has been identified, quantitation of that
analyte is based on the integrated abundance from the EICP of the
primary characteristic m/z in Table 5 or 6. Calculate the concentration
using the response factor (RF) determined in section 7.3.3 and Equation
2. If a calibration curve was used, calculate the concentration using
the regression equation for the curve. If the concentration of an
analyte exceeds the calibration range, dilute the sample by the minimum
amount to bring the concentration into the calibration range, and re-
analyze. Determine a dilution factor (DF) from the amount of the
dilution. For example, if the extract is diluted by a factor of 2, DF =
2.
[GRAPHIC] [TIFF OMITTED] TR28AU17.013
[[Page 260]]
Where:
Cs = Concentration of the analyte in the sample, and the
other terms are as defined in Section 7.3.3.
13.2 Reporting of results
As noted in section 1.4.1, EPA has promulgated this method at 40 CFR
part 136 for use in wastewater compliance monitoring under the National
Pollutant Discharge Elimination System (NPDES). The data reporting
practices described here are focused on such monitoring needs and may
not be relevant to other uses of this method.
13.2.1 Report results for wastewater samples in [micro]g/L without
correction for recovery. (Other units may be used if required by a
permit.) Report all QC data with the sample results.
13.2.2 Reporting level. Unless otherwise specified in by a
regulatory authority or in a discharge permit, results for analytes that
meet the identification criteria are reported down to the concentration
of the ML established by the laboratory through calibration of the
instrument (see section 7.3.2 and the glossary for the derivation of the
ML). EPA considers the terms ``reporting limit,'' ``limit of
quantitation,'' ``quantitation limit,'' and ``minimum level'' to be
synonymous.
13.2.2.1 Report a result for each analyte in each field sample or QC
standard at or above the ML to 3 significant figures. Report a result
for each analyte found in each field sample or QC standard below the ML
as ``12, are hazardous and must
be handled and disposed of as hazardous waste, or neutralized and
disposed of in accordance with all federal, state, and local
regulations. It is the laboratory's responsibility to comply with all
federal, state, and local regulations governing waste management,
particularly the hazardous waste identification rules and land disposal
restrictions. The laboratory using this method has the responsibility to
protect the air, water, and land by minimizing and controlling all
releases from fume hoods and bench operations. Compliance is also
required with any sewage discharge permits and regulations. For further
information on waste management, see ``The Waste Management Manual for
Laboratory Personnel,'' also available from the American Chemical
Society at the address in Section 15.3.
16.3 Many analytes in this method decompose above 500 [deg]C. Low-
level waste such as absorbent paper, tissues, and plastic gloves may be
burned in an appropriate incinerator. Gross quantities of neat or highly
concentrated solutions of toxic or hazardous chemicals should be
packaged securely and disposed of through commercial or governmental
channels that are capable of handling these types of wastes.
16.4 For further information on waste management, consult ``Waste
Management Manual for Laboratory Personnel and Less is Better-Laboratory
Chemical Management for Waste Reduction,'' available from the American
Chemical Society's Department of Government Relations and Science
Policy, 1155 16th Street NW., Washington, DC 20036, 202-872-4477.
17. References
1. Bellar, T.A. and Lichtenberg, J.J. ``Determining Volatile
Organics at Microgram-per-Litre Levels by Gas Chromatography,'' Journal
American Water Works Association, 66: 739 (1974).
2. ``Sampling and Analysis Procedures for Screening of Industrial
Effluents for Priority Pollutants,'' U.S. Environmental Protection
Agency, Environmental Monitoring and Support Laboratory, Cincinnati,
Ohio 45268, March 1977, Revised April 1977.
3. Bellar, T.A. and Lichtenberg, J.J. ``Semi-Automated Headspace
Analysis of Drinking Waters and Industrial Waters for Purgeable Volatile
Organic Compounds,'' Measurement of Organic Pollutants in Water and
Wastewater, C.E. Van Hall, editor, American Society for Testing and
Materials, Philadelphia, PA. Special Technical Publication 686, 1978.
4. ``EPA Method Study 29 EPA Method 624-Purgeables,'' EPA 600/4-84-
054, National Technical Information Service, PB84-209915, Springfield,
Virginia 22161, June 1984.
5. 40 CFR part 136, appendix B.
6. ``Method Detection Limit for Methods 624 and 625,'' Olynyk, P.,
Budde, W.L., and Eichelberger, J.W. Unpublished report, May 14, 1980.
7. ``Carcinogens-Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
8. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
9. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 7th Edition, 2003.
10. 40 CFR 136.6(b)(5)(x).
11. 40 CFR 136.6(b)(2)(i).
12. Protocol for EPA Approval of New Methods for Organic and
Inorganic Analytes in Wastewater and Drinking Water (EPA-821-B-98-003)
March 1999.
13. Provost, L.P. and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983).
14. 40 CFR 136.3(a), Table IB, Chlorine--Total residual.
15. Budde, W.L. and Eichelberger, J.W. ``Performance Tests for the
Evaluation of Computerized Gas Chromatography/Mass Spectrometry
Equipment and Laboratories,'' EPA-600/4-80-025, U.S. Environmental
Protection Agency, Environmental Monitoring and Support Laboratory,
Cincinnati, Ohio 45268, April 1980.
16. ``Method Performance Data for Method 624,'' Memorandum from R.
Slater and T. Pressley, U.S. Environmental Protection Agency,
Environmental Monitoring and Support Laboratory, Cincinnati, Ohio 45268,
January 17, 1984.
18. Tables
[[Page 262]]
Table 1--Purgeables \1\
----------------------------------------------------------------------------------------------------------------
CAS Registry MDL ([micro]g/ ML ([micro]g/
Analyte No. L) \2\ L) \3\
----------------------------------------------------------------------------------------------------------------
Acrolein........................................................ 107-02-8
Acrylonitrile................................................... 107-13-1
Benzene......................................................... 71-43-2 4.4 13.2
Bromodichloromethane............................................ 75-27-4 2.2 6.6
Bromoform....................................................... 75-25-2 4.7 14.1
Bromomethane.................................................... 74-83-9
Carbon tetrachloride............................................ 56-23-5 2.8 8.4
Chlorobenzene................................................... 108-90-7 6.0 18.0
Chloroethane.................................................... 75-00-3
2-Chloroethylvinyl ether........................................ 110-75-8
Chloroform...................................................... 67-66-3 1.6 4.8
Chloromethane................................................... 74-87-3
Dibromochloromethane............................................ 124-48-1 3.1 9.3
1,2-Dichlorobenzene............................................. 95-50-1
1,3-Dichlorobenzene............................................. 541-73-1
1,4-Dichlorobenzene............................................. 106-46-7
1,1-Dichloroethane.............................................. 75-34-3 4.7 14.1
1,2-Dichloroethane.............................................. 107-06-2 2.8 8.4
1,1-Dichloroethene.............................................. 75-35-4 2.8 8.4
trans-1,2-Dichloroethene........................................ 156-60-5 1.6 4.8
1,2-Dichloropropane............................................. 78-87-5 6.0 18.0
cis-1,3-Dichloropropene......................................... 10061-01-5 5.0 15.0
trans-1,3-Dichloropropene....................................... 10061-02-6
Ethyl benzene................................................... 100-41-4 7.2 21.6
Methylene chloride.............................................. 75-09-2 2.8 8.4
1,1,2,2-Tetrachloroethane....................................... 79-34-5 6.9 20.7
Tetrachloroethene............................................... 127-18-4 4.1 12.3
Toluene......................................................... 108-88-3 6.0 18.0
1,1,1-Trichloroethane........................................... 71-55-6 3.8 11.4
1,1,2-Trichloroethane........................................... 79-00-5 5.0 15.0
Trichloroethene................................................. 79-01-6 1.9 5.7
Vinyl chloride.................................................. 75-01-4 ..............
----------------------------------------------------------------------------------------------------------------
\1\ All the analytes in this table are Priority Pollutants (40 CFR part 423, appendix A).
\2\ MDL values from the 1984 promulgated version of Method 624.
\3\ ML = Minimum Level--see Glossary for definition and derivation.
Table 2--Additional Purgeables
------------------------------------------------------------------------
Analyte CAS Registry
------------------------------------------------------------------------
Acetone \1\............................................. 67-64-1
Acetonitrile \2\........................................ 75-05-8
Acrolein................................................ 107-02-8
Acrylonitrile........................................... 107-13-1
Allyl alcohol \1\....................................... 107-18-6
Allyl chloride.......................................... 107-05-1
t-Amyl ethyl ether (TAEE)............................... 919-94-8
t-Amyl methyl ether (TAME).............................. 994-058
Benzyl chloride......................................... 100-44-7
Bromoacetone \2\........................................ 598-31-2
Bromobenzene............................................ 108-86-1
Bromochloromethane...................................... 74-97-5
1,3-Butadiene........................................... 106-99-0
n-Butanol \1\........................................... 71-36-3
2-Butanone (MEK) \1 2\.................................. 78-93-3
t-Butyl alcohol (TBA)................................... 75-65-0
n-Butylbenzene.......................................... 104-51-8
sec-Butylbenzene........................................ 135-98-8
t-Butylbenzene.......................................... 98-06-6
t-Butyl ethyl ether (ETBE).............................. 637-92-3
Carbon disulfide........................................ 75-15-0
Chloral hydrate \2\..................................... 302-17-0
Chloroacetonitrile \1\.................................. 107-14-2
1-Chlorobutane.......................................... 109-69-3
Chlorodifluoromethane................................... 75-45-6
2-Chloroethanol \2\..................................... 107-07-3
bis (2-Chloroethyl) sulfide \2\......................... 505-60-2
1-Chlorohexanone........................................ 20261-68-1
Chloroprene (2-chloro-1,3-butadiene).................... 126-99-8
3-Chloropropene......................................... 107-05-1
3-Chloropropionitrile................................... 542-76-7
2-Chlorotoluene......................................... 95-49-8
4-Chlorotoluene......................................... 106-43-4
Crotonaldehyde \1 2\.................................... 123-73-9
Cyclohexanone........................................... 108-94-1
1,2-Dibromo-3-chloropropane............................. 96-12-8
1,2-Dibromoethane....................................... 106-93-4
Dibromomethane.......................................... 74-95-3
cis-1,4-Dichloro-2-butene............................... 1476-11-5
trans-1,4-Dichloro-2-butene............................. 110-57-6
cis-1,2-Dichloroethene.................................. 156-59-2
Dichlorodifluoromethane................................. 75-71-8
1,3-Dichloropropane..................................... 142-28-9
2,2-Dichloropropane..................................... 590-20-7
1,3-Dichloro-2-propanol \2\............................. 96-23-1
1,1-Dichloropropene..................................... 563-58-6
cis-1,3-Dichloropropene................................. 10061-01-5
1:2,3:4-Diepoxybutane................................... 1464-53-5
Diethyl ether........................................... 60-29-7
Diisopropyl ether (DIPE)................................ 108-20-3
1,4-Dioxane \2\......................................... 123-91-1
Epichlorohydrin \2\..................................... 106-89-8
Ethanol \2\............................................. 64-17-5
Ethyl acetate \2\....................................... 141-78-6
Ethyl methacrylate...................................... 97-63-2
Ethylene oxide \2\...................................... 75-21-8
Hexachlorobutadiene..................................... 87-63-3
Hexachloroethane........................................ 67-72-1
2-Hexanone \2\.......................................... 591-78-6
Iodomethane............................................. 74-88-4
Isobutyl alcohol \1\.................................... 78-83-1
Isopropylbenzene........................................ 98-82-8
[[Page 263]]
p-Isopropyltoluene...................................... 99-87-6
Methacrylonitrile \2\................................... 126-98-7
Methanol \2\............................................ 67-56-1
Malonitrile \2\......................................... 109-77-3
Methyl acetate.......................................... 79-20-9
Methyl acrylate......................................... 96-33-3
Methyl cyclohexane...................................... 108-87-2
Methyl iodide........................................... 74-88-4
Methyl methacrylate..................................... 78-83-1
4-Methyl-2-pentanone (MIBK) \2\......................... 108-10-1
Methyl-t-butyl ether (MTBE)............................. 1634-04-4
Naphthalene............................................. 91-20-3
Nitrobenzene............................................ 98-95-3
N-Nitroso-di-n-butylamine \2\........................... 924-16-3
2-Nitropropane.......................................... 79-46-9
Paraldehyde \2\......................................... 123-63-7
Pentachloroethane \2\................................... 76-01-7
Pentafluorobenzene...................................... 363-72-4
2-Pentanone \2\......................................... 107-19-7
2-Picoline \2\.......................................... 109-06-8
1-Propanol \1\.......................................... 71-23-8
2-Propanol \1\.......................................... 67-63-0
Propargyl alcohol \2\................................... 107-19-7
beta-Propiolactone \2\.................................. 57-58-8
Propionitrile (ethyl cyanide) \1\....................... 107-12-0
n-Propylamine........................................... 107-10-8
n-Propylbenzene......................................... 103-65-1
Pyridine \2\............................................ 110-86-1
Styrene................................................. 100-42-5
1,1,1,2-Tetrachloroethane............................... 630-20-6
Tetrahydrofuran......................................... 109-99-9
o-Toluidine \2\......................................... 95-53-4
1,2,3-Trichlorobenzene.................................. 87-61-6
Trichlorofluoromethane.................................. 75-69-4
1,2,3-Trichloropropane.................................. 96-18-4
1,2,3-Trimethylbenzene.................................. 526-73-8
1,2,4-Trimethylbenzene.................................. 95-63-6
1,3,5-Trimethylbenzene.................................. 108-67-8
Vinyl acetate........................................... 108-05-4
m-Xylene \3\............................................ 108-38-3
o-Xylene \3\............................................ 95-47-6
p-Xylene \3\............................................ 106-42-3
m+o-Xylene \3\.......................................... 179601-22-0
m+p-Xylene \3\.......................................... 179601-23-1
o+p-Xylene \3\.......................................... 136777-61-2
------------------------------------------------------------------------
\1\ Determined at a purge temperature of 80 [deg]C.
\2\ May be detectable at a purge temperature of 80 [deg]C.
\3\ Determined in combination separated by GC column. Most GC columns
will resolve o-xylene from m+p-xylene. Report using the CAS number for
the individual xylene or the combination, as determined.
Table 3--Example Retention Times
------------------------------------------------------------------------
Retention time
Analyte (min)
------------------------------------------------------------------------
Chloromethane........................................... 3.68
Vinyl chloride.......................................... 3.92
Bromomethane............................................ 4.50
Chloroethane............................................ 4.65
Trichlorofluoromethane.................................. 5.25
Diethyl ether........................................... 5.88
Acrolein................................................ 6.12
1,1-Dichloroethene...................................... 6.30
Acetone................................................. 6.40
Iodomethane............................................. 6.58
Carbon disulfide........................................ 6.72
3-Chloropropene......................................... 6.98
Methylene chloride...................................... 7.22
Acrylonitrile........................................... 7.63
trans-1,2-Dichloroethene................................ 7.73
1,1-Dichloroethane...................................... 8.45
Vinyl acetate........................................... 8.55
Allyl alcohol........................................... 8.58
2-Chloro-1,3-butadiene.................................. 8.65
Methyl ethyl ketone..................................... 9.50
cis-1,2-Dichloroethene.................................. 9.50
Ethyl cyanide........................................... 9.57
Methacrylonitrile....................................... 9.83
Chloroform.............................................. 10.05
1,1,1-Trichloroethane................................... 10.37
Carbon tetrachloride.................................... 10.70
Isobutanol.............................................. 10.77
Benzene................................................. 10.98
1,2-Dichloroethane...................................... 11.00
Crotonaldehyde.......................................... 11.45
Trichloroethene......................................... 12.08
1,2-Dichloropropane..................................... 12.37
Methyl methacrylate..................................... 12.55
p-Dioxane............................................... 12.63
Dibromomethane.......................................... 12.65
Bromodichloromethane.................................... 12.95
Chloroacetonitrile...................................... 13.27
2-Chloroethylvinyl ether................................ 13.45
cis-1,3-Dichloropropene................................. 13.65
4-Methyl-2-pentanone.................................... 13.83
Toluene................................................. 14.18
trans-1,3-Dichloropropene............................... 14.57
Ethyl methacrylate...................................... 14.70
1,1,2-Trichloroethane................................... 14.93
1,3-Dichloropropane..................................... 15.18
Tetrachloroethene....................................... 15.22
2-Hexanone.............................................. 15.30
Dibromochloromethane.................................... 15.68
1,2-Dibromoethane....................................... 15.90
Chlorobenzene........................................... 16.78
Ethylbenzene............................................ 16.82
1,1,1,2-Tetrachloroethane............................... 16.87
m+p-Xylene.............................................. 17.08
o-Xylene................................................ 17.82
Bromoform............................................... 18.27
Bromofluorobenzene...................................... 18.80
1,1,2,2-Tetrachloroethane............................... 18.98
1,2,3-Trichloropropane.................................. 19.08
trans-1,4-Dichloro-2-butene............................. 19.12
------------------------------------------------------------------------
Column: 75 m x 0.53 mm ID x 3.0 [micro]m wide-bore DB-624
Conditions: 40 [deg]C for 4 min, 9 [deg]C/min to 200 [deg]C, 20 [deg]C/
min (or higher) to 250 [deg]C, hold for 20 min at 250 [deg]C to remove
water.
Carrier gas flow rate: 6-7 mL/min at 40 [deg]C.
Inlet split ratio: 3:1.
Interface split ratio: 7:2.
Table 4--BFB Key m/z Abundance Criteria \1\
------------------------------------------------------------------------
m/z Abundance criteria
------------------------------------------------------------------------
50........................................ 15-40% of m/z 95.
75........................................ 30-60% of m/z 95.
95........................................ Base Peak, 100% Relative
Abundance.
96........................................ 5-9% of m/z 95.
173....................................... <2% of m/z 174.
174....................................... 50% of m/z 95.
175....................................... 5-9% of m/z 174.
176....................................... 95% but <101% of
m/z 174.
[[Page 264]]
177....................................... 5-9% of m/z 176.
------------------------------------------------------------------------
\1\ Abundance criteria are for a quadrupole mass spectrometer.
Alternative tuning criteria from other published EPA reference methods
may be used, provided method performance is not adversely affected.
Alternative tuning criteria specified by an instrument manufacturer
may also be used for another type of mass spectrometer, or for an
alternative carrier gas, provided method performance is not adversely
affected.
Table 5--Suggested Surrogate and Internal Standards
----------------------------------------------------------------------------------------------------------------
Retention time Secondary m/
Analyte (min) \1\ Primary m/z z's
----------------------------------------------------------------------------------------------------------------
Benzene-d6...................................................... 10.95 84
4-Bromofluorobenzene............................................ 18.80 95 174, 176
Bromochloromethane.............................................. 9.88 128 49, 130, 51
2-Bromo-1-chloropropane......................................... 14.80 77 79, 156
2-Butanone-d5................................................... 9.33 77
Chloroethane-d5................................................. 4.63 71
Chloroform-\13\C................................................ 10.00 86
1,2-Dichlorobenzene-d4.......................................... .............. 152
1,4-Dichlorobutane.............................................. 18.57 55 90, 92
1,2-Dichloroethane-d4........................................... 10.88 102
1,1-Dichloroethene-d2........................................... 6.30 65
1,2-Dichloropropane-d6.......................................... 12.27 67
trans-1,3-Dichloropropene-d4.................................... 14.50 79
1,4-Difluorobenzene............................................. .............. 114 63, 88
Ethylbenzene-d10................................................ 16.77 98
Fluorobenzene................................................... .............. 96 70
2-Hexanone-d5................................................... 15.30 63
Pentafluorobenzene.............................................. .............. 168
1,1,2,2-Tetrachloroethane-d2.................................... 18.93 84
Toluene-d8...................................................... 14.13 100
Vinyl chloride-d3............................................... 3.87 65
----------------------------------------------------------------------------------------------------------------
\1\ For chromatographic conditions, see the footnote to Table 3.
Table 6--Characteristic m/z's for Purgeable Organics
------------------------------------------------------------------------
Analyte Primary m/z Secondary m/z's
------------------------------------------------------------------------
Acrolein.......................... 56 55 and 58.
Acrylonitrile..................... 53 52 and 51.
Chloromethane..................... 50 52.
Bromomethane...................... 94 96.
Vinyl chloride.................... 62 64.
Chloroethane...................... 64 66.
Methylene chloride................ 84 49, 51, and 86.
Trichlorofluoromethane............ 101 103.
1,1-Dichloroethene................ 96 61 and 98.
1,1-Dichloroethane................ 63 65, 83, 85, 98, and
100.
trans-1,2-Dichloroethene.......... 96 61 and 98.
Chloroform........................ 83 85.
1,2-Dichloroethane................ 98 62, 64, and 100.
1,1,1-Trichloroethane............. 97 99, 117, and 119.
Carbon tetrachloride.............. 117 119 and 121.
Bromodichloromethane.............. 83 127, 85, and 129.
1,2-Dichloropropane............... 63 112, 65, and 114.
trans-1,3-Dichloropropene......... 75 77.
Trichloroethene................... 130 95, 97, and 132.
Benzene........................... 78
Dibromochloromethane.............. 127 129, 208, and 206.
1,1,2-Trichloroethane............. 97 83, 85, 99, 132, and
134.
cis-1,3-Dichloropropene........... 75 77.
2-Chloroethylvinyl ether.......... 106 63 and 65.
Bromoform......................... 173 171, 175, 250, 252,
254, and 256.
1,1,2,2-Tetrachloroethane......... 168 83, 85, 131, 133,
and 166.
Tetrachloroethene................. 164 129, 131, and 166.
Toluene........................... 92 91.
Chlorobenzene..................... 112 114.
[[Page 265]]
Ethyl benzene..................... 106 91.
1,3-Dichlorobenzene............... 146 148 and 111.
1,2-Dichlorobenzene............... 146 148 and 111.
1,4-Dichlorobenzene............... 146 148 and 111.
------------------------------------------------------------------------
Table 7--LCS (Q), DOC (s and X), and MS/MSD (P and RPD) Acceptance Criteria \1\
----------------------------------------------------------------------------------------------------------------
Range for Q Limit for s Range for X Range for P1,
Analyte (%) (%) (%) P2 (%) Limit for RPD
----------------------------------------------------------------------------------------------------------------
Acrolein........................ 60-140 30 50-150 40-160 60
Acrylonitrile................... 60-140 30 50-150 40-160 60
Benzene......................... 65-135 33 75-125 37-151 61
Benzene-d6...................... .............. .............. ..............
Bromodichloromethane............ 65-135 34 50-140 35-155 56
Bromoform....................... 70-130 25 57-156 45-169 42
Bromomethane.................... 15-185 90 D-206 D-242 61
2-Butanone-d5................... .............. .............. ..............
Carbon tetrachloride............ 70-130 26 65-125 70-140 41
Chlorobenzene................... 65-135 29 82-137 37-160 53
Chloroethane.................... 40-160 47 42-202 14-230 78
Chloroethane-d5................. .............. .............. ..............
2-Chloroethylvinyl ether........ D-225 130 D-252 D-305 71
Chloroform...................... 70-135 32 68-121 51-138 54
Chloroform-\13\C................ .............. .............. ..............
Chloromethane................... D-205 472 D-230 D-273 60
Dibromochloromethane............ 70-135 30 69-133 53-149 50
1,2-Dichlorobenzene............. 65-135 31 59-174 18-190 57
1,2-Dichlorobenzene-d4.......... .............. .............. ..............
1,3-Dichlorobenzene............. 70-130 24 75-144 59-156 43
1,4-Dichlorobenzene............. 65-135 31 59-174 18-190 57
1,1-Dichloroethane.............. 70-130 24 71-143 59-155 40
1,2-Dichloroethane.............. 70-130 29 72-137 49-155 49
1,2-Dichloroethane-d4........... .............. .............. ..............
1,1-Dichloroethene.............. 50-150 40 19-212 D-234 32
1,1-Dichloroethene-d2........... .............. .............. ..............
trans-1,2-Dichloroethene........ 70-130 27 68-143 54-156 45
1,2-Dichloropropane............. 35-165 69 19-181 D-210 55
1,2-Dichloropropane-d6.......... .............. .............. ..............
cis-1,3-Dichloropropene......... 25-175 79 5-195 D-227 58
trans-1,3-Dichloropropene....... 50-150 52 38-162 17-183 86
trans-1,3-Dichloropropene-d4.... .............. .............. ..............
Ethyl benzene................... 60-140 34 75-134 37-162 63
2-Hexanone-d5................... .............. .............. ..............
Methylene chloride.............. 60-140 192 D-205 D-221 28
1,1,2,2-Tetrachloroethane....... 60-140 36 68-136 46-157 61
1,1,2,2-Tetrachloroethane-d2.... .............. .............. ..............
Tetrachloroethene............... 70-130 23 65-133 64-148 39
Toluene......................... 70-130 22 75-134 47-150 41
Toluene-d8...................... .............. .............. ..............
1,1,1-Trichloroethane........... 70-130 21 69-151 52-162 36
1,1,2-Trichloroethane........... 70-130 27 75-136 52-150 45
Trichloroethene................. 65-135 29 75-138 70-157 48
Trichlorofluoromethane.......... 50-150 50 45-158 17-181 84
Vinyl chloride.................. 5-195 100 D-218 D-251 66
Vinyl chloride-d3............... .............. .............. .............. ..............
----------------------------------------------------------------------------------------------------------------
\1\ Criteria were calculated using an LCS concentration of 20 [micro]g/L.
Q = Percent recovery in calibration verification/LCS (section 8.4).
s = Standard deviation of percent recovery for four recovery measurements (section 8.2.4).
X = Average percent recovery for four recovery measurements (section 8.2.4).
P = Percent recovery for the MS or MSD (section 8.3.3).
D = Detected; result must be greater than zero.
Notes:
1. Criteria for pollutants are based upon the method performance data in Reference 4. Where necessary, limits
have been broadened to assure applicability to concentrations below those used to develop Table 7.
2. Criteria for surrogates are from EPA CLP SOM01.2D.
[[Page 266]]
Table 8--Recovery and Precision as Functions of Concentration
----------------------------------------------------------------------------------------------------------------
Single analyst Overall
Recovery, precision, precision,
Analyte X[min] sr[min] S[min]
([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
Benzene......................................................... 0.93C+2.00 20.26 X-1.74 0.25 X-1.33
Bromodichloromethane............................................ 1.03C-1.58 0.15 X+0.59 0.20 X+1.13
Bromoform....................................................... 1.18C-2.35 0.12 X+0.36 0.17 X+1.38
Bromomethane \a\................................................ 1.00C 0.43 X 0.58 X
Carbon tetrachloride............................................ 1.10C-1.68 0.12 X+0.25 0.11 X+0.37
Chlorobenzene................................................... 0.98C+2.28 0.16 X-0.09 0.26 X-1.92
Chloroethane.................................................... 1.18C+0.81 0.14 X+2.78 0.29 X+1.75
2-Chloroethylvinyl ether \a\.................................... 1.00C 0.62 X 0.84 X
Chloroform...................................................... 0.93C+0.33 0.16 X+0.22 0.18 X+0.16
Chloromethane................................................... 1.03C+0.81 0.37 X+2.14 0.58 X+0.43
Dibromochloromethane............................................ 1.01C-0.03 0.17 X-0.18 0.17 X+0.49
1,2-Dichlorobenzene \b\......................................... 0.94C+4.47 0.22 X-1.45 0.30 X-1.20
1,3-Dichlorobenzene............................................. 1.06C+1.68 0.14 X-0.48 0.18 X-0.82
1,4-Dichlorobenzene \b\......................................... 0.94C+4.47 0.22 X-1.45 0.30 X-1.20
1,1-Dichloroethane.............................................. 1.05C+0.36 0.13 X-0.05 0.16 X+0.47
1,2-Dichloroethane.............................................. 1.02C+0.45 0.17 X-0.32 0.21 X-0.38
1,1-Dichloroethene.............................................. 1.12C+0.61 0.17 X+1.06 0.43 X-0.22
trans-1,2,-Dichloroethene....................................... 1.05C+0.03 0.14 X-+0.09 0.19 X-+0.17
1,2-Dichloropropane \a\......................................... 1.00C 0.33 X 0.45 X
cis-1,3-Dichloropropene \a\..................................... 1.00C 0.38 X 0.52 X
trans-1,3-Dichloropropene \a\................................... 1.00C 0.25 X 0.34 X
Ethyl benzene................................................... 0.98C+2.48 0.14 X+1.00 0.26 X-1.72
Methylene chloride.............................................. 0.87C+1.88 0.15 X+1.07 0.32 X+4.00
1,1,2,2-Tetrachloroethane....................................... 0.93C+1.76 0.16 X+0.69 0.20 X+0.41
Tetrachloroethene............................................... 1.06C+0.60 0.13 X-0.18 0.16 X-0.45
Toluene......................................................... 0.98C+2.03 0.15 X-0.71 0.22 X-1.71
1,1,1-Trichloroethane........................................... 1.06C+0.73 0.12 X-0.15 0.21 X-0.39
1,1,2-Trichloroethane........................................... 0.95C+1.71 0.14 X+0.02 0.18 X+0.00
Trichloroethene................................................. 1.04C+2.27 0.13 X+0.36 0.12 X+0.59
Trichlorofluoromethane.......................................... 0.99C+0.39 0.33 X-1.48 0.34 X-0.39
Vinyl chloride.................................................. 1.00C 0.48 X 0.65 X
----------------------------------------------------------------------------------------------------------------
X[min] = Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/
L.
Sr[min] = Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S[min] = Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C = True value for the concentration, in [micro]g/L.
X = Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
\a\ Estimates based upon the performance in a single laboratory (References 4 and 16).
\b\ Due to coelutions, performance statements for these isomers are based upon the sums of their concentrations.
19. Glossary
These definitions and purposes are specific to this method, but have
been conformed to common usage to the extent possible.
19.1 Units of weight and measure and their abbreviations.
19.1.1 Symbols.
[deg]C degrees Celsius
[micro]g microgram
[micro]L microliter
< less than
greater than
% percent
19.1.2 Abbreviations (in alphabetical order).
cm centimeter
g gram
h hour
ID inside diameter
in. inch
L liter
m mass
mg milligram
min minute
mL milliliter
mm millimeter
ms millisecond
m/z mass-to-charge ratio
N normal; gram molecular weight of solute divided by hydrogen equivalent
of solute, per liter of solution
ng nanogram
pg picogram
ppb part-per-billion
ppm part-per-million
ppt part-per-trillion
psig pounds-per-square inch gauge
v/v volume per unit volume
w/v weight per unit volume
19.2 Definitions and acronyms (in alphabetical order).
Analyte--A compound tested for by this method. The analytes are
listed in Tables 1 and 2.
Analyte of interest--An analyte of interest is an analyte required
to be determined by a regulatory/control authority or in a permit, or by
a client.
Analytical batch--The set of samples analyzed on a given instrument
during a 12-hour period that begins with analysis of a calibration
verification/LCS. See section 8.4.
[[Page 267]]
Blank--An aliquot of reagent water that is treated exactly as a
sample including exposure to all glassware, equipment, solvents,
reagents, internal standards, and surrogates that are used with samples.
The blank is used to determine if analytes or interferences are present
in the laboratory environment, the reagents, or the apparatus. See
section 8.5.
Calibration--The process of determining the relationship between the
output or response of a measuring instrument and the value of an input
standard. Historically, EPA has referred to a multi-point calibration as
the ``initial calibration,'' to differentiate it from a single-point
calibration verification.
Calibration standard--A solution prepared from stock solutions and/
or a secondary standards and containing the analytes of interest,
surrogates, and internal standards. The calibration standard is used to
calibrate the response of the GC/MS instrument against analyte
concentration.
Calibration verification standard--The laboratory control sample
(LCS) used to verify calibration. See Section 8.4.
Descriptor--In SIM, the beginning and ending retention times for the
RT window, the m/z's sampled in the RT window, and the dwell time at
each m/z.
Extracted ion current profile (EICP)--The line described by the
signal at a given m/z.
Field duplicates--Two samples collected at the same time and place
under identical conditions, and treated identically throughout field and
laboratory procedures. Results of analyses of field duplicates provide
an estimate of the precision associated with sample collection,
preservation, and storage, as well as with laboratory procedures.
Field blank--An aliquot of reagent water or other reference matrix
that is placed in a sample container in the field, and treated as a
sample in all respects, including exposure to sampling site conditions,
storage, preservation, and all analytical procedures. The purpose of the
field blank is to determine if the field or sample transporting
procedures and environments have contaminated the sample.
GC--Gas chromatograph or gas chromatography.
Internal standard--A compound added to a sample in a known amount
and used as a reference for quantitation of the analytes of interest and
surrogates. Internal standards are listed in Table 5. Also see Internal
standard quantitation.
Internal standard quantitation--A means of determining the
concentration of an analyte of interest (Tables 1 and 2) by reference to
a compound added to a sample and not expected to be found in the sample.
DOC--Initial demonstration of capability (DOC; section 8.2); four
aliquots of reagent water spiked with the analytes of interest and
analyzed to establish the ability of the laboratory to generate
acceptable precision and recovery. A DOC is performed prior to the first
time this method is used and any time the method or instrumentation is
modified.
Laboratory control sample (LCS; laboratory fortified blank (LFB);
on-going precision and recovery sample; OPR)--An aliquot of reagent
water spiked with known quantities of the analytes of interest and
surrogates. The LCS is analyzed exactly like a sample. Its purpose is to
assure that the results produced by the laboratory remain within the
limits specified in this method for precision and recovery. In this
method, the LCS is synonymous with a calibration verification sample
(See sections 7.4 and 8.4).
Laboratory fortified sample matrix--See Matrix spike.
Laboratory reagent blank--See Blank.
Matrix spike (MS) and matrix spike duplicate (MSD) (laboratory
fortified sample matrix and duplicate)--Two aliquots of an environmental
sample to which known quantities of the analytes of interest and
surrogates are added in the laboratory. The MS/MSD are prepared and
analyzed exactly like a field sample. Their purpose is to quantify any
additional bias and imprecision caused by the sample matrix. The
background concentrations of the analytes in the sample matrix must be
determined in a separate aliquot and the measured values in the MS/MSD
corrected for background concentrations.
May--This action, activity, or procedural step is neither required
nor prohibited.
May not--This action, activity, or procedural step is prohibited.
Method blank (laboratory reagent blank)--See Blank.
Method detection limit (MDL)--A detection limit determined by the
procedure at 40 CFR part 136, appendix B. The MDLs determined by EPA in
the original version of the method are listed in Table 1. As noted in
Sec. 1.4, use the MDLs in Table 1 in conjunction with current MDL data
from the laboratory actually analyzing samples to assess the sensitivity
of this procedure relative to project objectives and regulatory
requirements (where applicable).
Minimum level (ML)--The term ``minimum level'' refers to either the
sample concentration equivalent to the lowest calibration point in a
method or a multiple of the method detection limit (MDL), whichever is
higher. Minimum levels may be obtained in several ways: They may be
published in a method; they may be based on the lowest acceptable
calibration point used by a laboratory; or they may be calculated by
multiplying the MDL in a method, or the MDL determined by a laboratory,
by a factor of 3. For the purposes of NPDES compliance monitoring, EPA
considers the following terms to
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be synonymous: ``quantitation limit,'' ``reporting limit,'' and
``minimum level.''
MS--Mass spectrometer or mass spectrometry.
Must--This action, activity, or procedural step is required.
m/z--The ratio of the mass of an ion (m) detected in the mass
spectrometer to the charge (z) of that ion.
Quality control sample (QCS)--A sample containing analytes of
interest at known concentrations. The QCS is obtained from a source
external to the laboratory or is prepared from standards obtained from a
different source than the calibration standards.
The purpose is to check laboratory performance using test materials
that have been prepared independent of the normal preparation process.
Reagent water--Water demonstrated to be free from the analytes of
interest and potentially interfering substances at the MDLs for the
analytes in this method.
Regulatory compliance limit (or regulatory concentration limit)--A
limit on the concentration or amount of a pollutant or contaminant
specified in a nationwide standard, in a permit, or otherwise
established by a regulatory/control authority.
Relative retention time (RRT)--The ratio of the retention time of an
analyte to the retention time of its associated internal standard. RRT
compensates for small changes in the GC temperature program that can
affect the absolute retention times of the analyte and internal
standard. RRT is a unitless quantity.
Relative standard deviation (RSD)--The standard deviation times 100
divided by the mean. Also termed ``coefficient of variation.''
RF--Response factor. See section 7.3.3.
RSD--See relative standard deviation.
Safety Data Sheet (SDS)--Written information on a chemical's
toxicity, health hazards, physical properties, fire, and reactivity,
including storage, spill, and handling precautions that meet the
requirements of OSHA, 29 CFR 1910.1200(g) and appendix D to Sec.
1910.1200. United Nations Globally Harmonized System of Classification
and Labelling of Chemicals (GHS), third revised edition, United Nations,
2009.
Selected Ion Monitoring (SIM)--An MS technique in which a few m/z's
are monitored. When used with gas chromatography, the m/z's monitored
are usually changed periodically throughout the chromatographic run to
correlate with the characteristic m/z's for the analytes, surrogates,
and internal standards as they elute from the chromatographic column.
The technique is often used to increase sensitivity and minimize
interferences.
Signal-to-noise ratio (S/N)--The height of the signal as measured
from the mean (average) of the noise to the peak maximum divided by the
width of the noise.
SIM--See Selection Ion Monitoring.
Should--This action, activity, or procedural step is suggested but
not required.
Stock solution--A solution containing an analyte that is prepared
using a reference material traceable to EPA, the National Institute of
Science and Technology (NIST), or a source that will attest to the
purity and authenticity of the reference material.
Surrogate--A compound unlikely to be found in a sample, and which is
spiked into sample in a known amount before purge-and-trap. The
surrogate is quantitated with the same procedures used to quantitate the
analytes of interest. The purpose of the surrogate is to monitor method
performance with each sample.
VOA--Volatile organic analysis: e.g., the analysis performed by this
method.
Method 625.1--Base/Neutrals and Acids by GC/MS
1. Scope and Application
1.1 This method is for determination of semivolatile organic
pollutants in industrial discharges and other environmental samples by
gas chromatography combined with mass spectrometry (GC/MS), as provided
under 40 CFR 136.1. This revision is based on a previous protocol
(Reference 1), on the basic revision promulgated October 26, 1984, and
on an interlaboratory method validation study (Reference 2). Although
this method was validated through an interlaboratory study conducted in
the early 1980s, the fundamental chemistry principles used in this
method remain sound and continue to apply.
1.2 The analytes that may be qualitatively and quantitatively
determined using this method and their CAS Registry numbers are listed
in Tables 1 and 2. The method may be extended to determine the analytes
listed in Table 3; however, extraction or gas chromatography of some of
these analytes may make quantitative determination difficult. For
example, benzidine is subject to oxidative losses during extraction and/
or solvent concentration. Under the alkaline conditions of the
extraction, alpha-BHC, gamma-BHC, endosulfan I and II, and endrin are
subject to decomposition. Hexachlorocyclopentadiene is subject to
thermal decomposition in the inlet of the gas chromatograph, chemical
reaction in acetone solution, and photochemical decomposition. N-
nitrosodiphenylamine and other nitrosoamines may decompose in the gas
chromatographic inlet. The sample may be extracted at neutral pH if
necessary to overcome these or other decomposition problems that could
occur at alkaline or acidic pH. EPA also has provided other methods
(e.g., Method 607--Nitrosamines) that may be used for determination of
some of these analytes.
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EPA encourages use of Method 625.1 to determine additional compounds
amenable to extraction and GC/MS.
1.3 The large number of analytes in Tables 1-3 of this method makes
testing difficult if all analytes are determined simultaneously.
Therefore, it is necessary to determine and perform quality control (QC)
tests for the ``analytes of interest'' only. Analytes of interest are
those required to be determined by a regulatory/control authority or in
a permit, or by a client. If a list of analytes is not specified, the
analytes in Tables 1 and 2 must be determined, at a minimum, and QC
testing must be performed for these analytes. The analytes in Tables 1
and 2, and some of the analytes in Table 3 have been identified as Toxic
Pollutants (40 CFR 401.15), expanded to a list of Priority Pollutants
(40 CFR part 423, appendix A).
1.4 In this revision to Method 625, the pesticides and
polychlorinated biphenyls (PCBs) have been moved from Table 1 to Table 3
(Additional Analytes) to distinguish these analytes from the analytes
required in quality control tests (Tables 1 and 2). QC acceptance
criteria for pesticides and PCBs have been retained in Table 6 and may
continue to be applied if desired, or if requested or required by a
regulatory/control authority or in a permit. Method 608.3 should be used
for determination of pesticides and PCBs. However, if pesticides and/or
PCBs are to be determined, an additional sample must be collected and
extracted using the pH adjustment and extraction procedures specified in
Method 608.3. Method 1668C may be useful for determination of PCBs as
individual chlorinated biphenyl congeners, and Method 1699 may be useful
for determination of pesticides. At the time of writing of this
revision, Methods 1668C and 1699 had not been approved for use at 40 CFR
part 136. The screening procedure for 2,3,7,8-tetrachlorodibenzo-p-
dioxin (2,3,7,8-TCDD) contained in the version of Method 625 promulgated
October 26, 1984 has been replaced with procedures for selected ion
monitoring (SIM), and 2,3,7,8-TCDD may be determined using the SIM
procedures. However, EPA Method 613 or 1613B should be used for analyte-
specific determination of 2,3,7,8-TCDD because of the focus of these
methods on this compound. Methods 613 and 1613B are approved for use at
40 CFR part 136.
1.5 Method detection limits (MDLs; Reference 3) for the analytes in
Tables 1, 2, and 3 are listed in those tables. These MDLs were
determined in reagent water (Reference 4). Advances in analytical
technology, particularly the use of capillary (open-tubular) columns,
allowed laboratories to routinely achieve MDLs for the analytes in this
method that are 2-10 times lower than those in the version promulgated
in 1984. The MDL for an analyte in a specific wastewater may differ from
those listed, depending upon the nature of interferences in the sample
matrix.
1.5.1 EPA has promulgated this method at 40 CFR part 136 for use in
wastewater compliance monitoring under the National Pollutant Discharge
Elimination System (NPDES). The data reporting practices described in
section 15.2 are focused on such monitoring needs and may not be
relevant to other uses of the method.
1.5.2 This method includes ``reporting limits'' based on EPA's
``minimum level'' (ML) concept (see the glossary in section 22). Tables
1, 2, and 3 contain MDL values and ML values for many of the analytes.
1.6 This method is performance-based. It may be modified to improve
performance (e.g., to overcome interferences or improve the accuracy of
results) provided all performance requirements are met.
1.6.1 Examples of allowed method modifications are described at 40
CFR 136.6. Other examples of allowed modifications specific to this
method, including solid-phase extraction (SPE) are described in section
8.1.2.
1.6.2 Any modification beyond those expressly permitted at 40 CFR
136.6 or in section 8.1.2 of this method shall be considered a major
modification subject to application and approval of an alternate test
procedure under 40 CFR 136.4 and 136.5.
1.6.3 For regulatory compliance, any modification must be
demonstrated to produce results equivalent or superior to results
produced by this method when applied to relevant wastewaters (section
8.3).
1.7 This method is restricted to use by or under the supervision of
analysts experienced in the use of a gas chromatograph/mass spectrometer
and in the interpretation of mass spectra. Each laboratory that uses
this method must demonstrate the ability to generate acceptable results
using the procedure in Section 8.2.
1.8 Terms and units of measure used in this method are given in the
glossary at the end of the method.
2. Summary of Method
2.1 A measured volume of sample, sufficient to meet an MDL or
reporting limit, is serially extracted with methylene chloride at pH 11-
13 and again at a pH less than 2 using a separatory funnel or continuous
liquid/liquid extractor.
2.2 The extract is concentrated to a volume necessary to meet the
required compliance or detection limit, and analyzed by GC/MS.
Qualitative identification of an analyte in the extract is performed
using the retention time and the relative abundance of two or more
characteristic masses (m/z's). Quantitative analysis is performed using
the internal standard technique with a single characteristic m/z.
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3. Contamination and Interferences
3.1 Solvents, reagents, glassware, and other sample processing
labware may yield artifacts, elevated baselines, or matrix interferences
causing misinterpretation of chromatograms and mass spectra. All
materials used in the analysis must be demonstrated to be free from
contamination and interferences by analyzing blanks initially and with
each extraction batch (samples started through the extraction process in
a given 24-hour period, to a maximum of 20 samples--see Glossary for
detailed definition), as described in Section 8.5. Specific selection of
reagents and purification of solvents by distillation in all-glass
systems may be required. Where possible, labware is cleaned by
extraction or solvent rinse, or baking in a kiln or oven.
3.2 Glassware must be scrupulously cleaned (Reference 5). Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed by detergent washing with
hot water, and rinses with tap water and reagent water. The glassware
should then be drained dry, and heated at 400 [deg]C for 15-30 minutes.
Some thermally stable materials, such as PCBs, may require higher
temperatures and longer baking times for removal. Solvent rinses with
pesticide quality acetone, hexane, or other solvents may be substituted
for heating. Do not heat volumetric labware above 90 [deg]C. After
drying and cooling, store inverted or capped with solvent-rinsed or
baked aluminum foil in a clean environment to prevent accumulation of
dust or other contaminants.
3.3 Matrix interferences may be caused by contaminants co-extracted
from the sample. The extent of matrix interferences will vary
considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled.
Interferences extracted from samples high in total organic carbon (TOC)
may result in elevated baselines, or by enhancing or suppressing a
signal at or near the retention time of an analyte of interest. Analyses
of the matrix spike and duplicate (section 8.3) may be useful in
identifying matrix interferences, and gel permeation chromatography
(GPC; Section 11.1) and sulfur removal (section 11.2) may aid in
eliminating these interferences. EPA has provided guidance that may aid
in overcoming matrix interferences (Reference 6).
3.4 In samples that contain an inordinate number of interferences,
the use of chemical ionization (CI) or triple quadrupole (MRM) mass
spectrometry may make identification easier. Tables 4 and 5 give
characteristic CI and MRM m/z's for many of the analytes covered by this
method. The use of CI or MRM mass spectrometry may be utilized to
support electron ionization (EI) mass spectrometry or as a primary
method for identification and quantification. While the use of these
enhanced techniques is encouraged, it is not required.
4. Safety
4.1 Hazards associated with each reagent used in this method have
not been precisely defined; however, each chemical compound should be
treated as a potential health hazard. From this viewpoint, exposure to
these chemicals must be reduced to the lowest possible level by whatever
means available. The laboratory is responsible for maintaining a current
awareness file of OSHA regulations regarding the safe handling of the
chemicals specified in this method. A reference file of safety data
sheets (SDSs, OSHA, 29 CFR 1910.1200(g)) should also be made available
to all personnel involved in sample handling and chemical analysis.
Additional references to laboratory safety are available and have been
identified (References 7-9) for the information of the analyst.
4.2 The following analytes covered by this method have been
tentatively classified as known or suspected human or mammalian
carcinogens: Benzo(a)anthracene, benzidine, 3,3[min]-dichlorobenzidine,
benzo(a)pyrene, alpha-BHC, beta-BHC, delta-BHC, gamma-BHC, Dibenz(a,h)-
anthracene, N-nitrosodimethylamine, 4,4[min]-DDT, and PCBs. Other
compounds in Table 3 may also be toxic. Primary standards of toxic
compounds should be prepared in a chemical fume hood, and a NIOSH/MESA
approved toxic gas respirator should be worn when handling high
concentrations of these compounds.
4.3 This method allows the use of hydrogen as a carrier gas in place
of helium (section 5.6.1.2). The laboratory should take the necessary
precautions in dealing with hydrogen, and should limit hydrogen flow at
the source to prevent buildup of an explosive mixture of hydrogen in
air.
5. Apparatus and Materials
Note: Brand names, suppliers, and part numbers are for illustration
purposes only. No endorsement is implied. Equivalent performance may be
achieved using equipment and materials other than those specified here.
Demonstrating that the equipment and supplies used in the laboratory
achieves the required performance is the responsibility of the
laboratory. Suppliers for equipment and materials in this method may be
found through an on-line search. Please do not contact EPA for supplier
information.
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--amber glass bottle large enough to contain
the necessary sample volume, fitted with a fluoropolymer-lined screw
cap. Foil may be substituted for fluoropolymer if the sample is not
corrosive.
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If amber bottles are not available, protect samples from light. Unless
pre-cleaned, the bottle and cap liner must be washed, rinsed with
acetone or methylene chloride, and dried before use to minimize
contamination.
5.1.2 Automatic sampler (optional)--the sampler must incorporate a
pre-cleaned glass sample container. Samples must be kept refrigerated at
<=6 [deg]C and protected from light during compositing. If the sampler
uses a peristaltic pump, a minimum length of compressible silicone
rubber tubing may be used. Before use, however, rinse the compressible
tubing with methanol, followed by repeated rinsing with reagent water,
to minimize the potential for sample contamination. An integrating flow
meter is required to collect flow-proportioned composites.
5.2 Glassware.
5.2.1 Separatory funnel--Size appropriate to hold sample volume and
extraction solvent volume, and equipped with fluoropolymer stopcock.
5.2.2 Drying column--Chromatographic column, approximately 400 mm
long by 19 mm ID, with coarse frit, or equivalent, sufficient to hold 15
g of anhydrous sodium sulfate.
5.2.3 Concentrator tube, Kuderna-Danish--10 mL, graduated (Kontes
570050-1025 or equivalent). Calibration must be checked at the volumes
employed in the test. A ground glass stopper is used to prevent
evaporation of extracts.
5.2.4 Evaporative flask, Kuderna-Danish--500 mL (Kontes 57001-0500
or equivalent). Attach to concentrator tube with springs.
Note: Use of a solvent recovery system with the K-D or other solvent
evaporation apparatus is strongly recommended.
5.2.5 Snyder column, Kuderna-Danish--Three-ball macro (Kontes
503000-0121 or equivalent).
5.2.6 Snyder column, Kuderna-Danish--Two-ball micro (Kontes 569001-
0219 or equivalent).
5.2.7 Vials--10-15 mL, amber glass, with Teflon-lined screw cap.
5.2.8 Continuous liquid-liquid extractor--Equipped with
fluoropolymer or glass connecting joints and stopcocks requiring no
lubrication. (Hershberg-Wolf Extractor, Ace Glass Company, Vineland, NJ,
P/N 6848-20, or equivalent.)
5.2.9 In addition to the glassware listed above, the laboratory
should be equipped with all necessary pipets, volumetric flasks,
beakers, and other glassware listed in this method and necessary to
perform analyses successfully.
5.3 Boiling chips--Approximately 10/40 mesh, glass, silicon carbide,
or equivalent. Heat to 400 [deg]C for 30 minutes, or solvent rinse or
Soxhlet extract with methylene chloride.
5.4 Water bath--Heated, with concentric ring cover, capable of
temperature control (2 [deg]C). The bath should be
used in a hood.
5.5 Balances.
5.5.1 Analytical, capable of accurately weighing 0.1 mg.
5.5.2 Top loading, capable of accurately weighing 10 mg.
5.6 GC/MS system.
5.6.1 Gas chromatograph (GC)--An analytical system complete with a
temperature programmable gas chromatograph and all required accessories,
including syringes and analytical columns.
5.6.1.1 Injection port--Can be split, splitless, temperature
programmable vaporization split/splitless (PTV), solvent-purge, large-
volume, on-column, backflushed, or other. An autosampler is highly
recommended because it injects volumes more precisely than volumes
injected manually.
5.6.1.2 Carrier gas--Helium or hydrogen. Data in the tables in this
method were obtained using helium carrier gas. If hydrogen is used,
analytical conditions may need to be adjusted for optimum performance,
and calibration and all QC tests must be performed with hydrogen carrier
gas. See Section 4.3 for precautions regarding the use of hydrogen as a
carrier gas.
5.6.2 GC column--See the footnotes to Tables 4 and 5. Other columns
or column systems may be used provided all requirements in this method
are met.
5.6.3 Mass spectrometer--Capable of repetitively scanning from 35-
450 Daltons (amu) every two seconds or less, utilizing a 70 eV (nominal)
electron energy in the electron impact ionization mode, and producing a
mass spectrum which meets all the criteria in Table 9A or 9B when 50 ng
or less of decafluorotriphenyl phosphine (DFTPP; CAS 5074-71-5;
bis(pentafluorophenyl) phenyl phosphine) is injected into the GC.
5.6.4 GC/MS interface--Any GC to MS interface that meets all
performance requirements in this method may be used.
5.6.5 Data system--A computer system must be interfaced to the mass
spectrometer that allows the continuous acquisition and storage of mass
spectra acquired throughout the chromatographic program. The computer
must have software that allows searching any GC/MS data file for
specific m/z's (masses) and plotting m/z abundances versus time or scan
number. This type of plot is defined as an extracted ion current profile
(EICP). Software must also be available that allows integrating the
abundance at any EICP between specified time or scan number limits.
5.7 Automated gel permeation chromatograph (GPC).
5.7.1 GPC column--150-700 mm long x 21-25 mm ID, packed with 70 g of
SX-3 Biobeads; Bio-Rad Labs, or equivalent.
5.7.2 Pump, injection valve, UV detector, and other apparatus
necessary to meet the requirements in this method.
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5.8 Nitrogen evaporation device--Equipped with a water bath than can
be maintained at 30-45 [deg]C; N-Evap, Organomation Associates, or
equivalent.
5.9 Muffle furnace or kiln--Capable of baking glassware or sodium
sulfate in the range of 400-450 [deg]C.
6. Reagents
6.1 Reagent water--Reagent water is defined as water in which the
analytes of interest and interfering compounds are not detected at the
MDLs of the analytes of interest.
6.2 Sodium hydroxide solution (10 N)--Dissolve 40 g of NaOH (ACS) in
reagent water and dilute to 100 mL.
6.3 Sodium thiosulfate--(ACS) granular.
6.4 Sulfuric acid (1+1)--Slowly add 50 mL of
H2SO4 (ACS, sp. gr. 1.84) to 50 mL of reagent
water.
6.5 Acetone, methanol, methylene chloride, 2-propanol--High purity
pesticide quality, or equivalent, demonstrated to be free of the
analytes of interest and interferences (Section 3). Purification of
solvents by distillation in all-glass systems may be required.
6.6 Sodium sulfate--(ACS) granular, anhydrous, rinsed or Soxhlet
extracted with methylene chloride (20 mL/g), baked in a shallow tray at
450 [deg]C for one hour minimum, cooled in a desiccator, and stored in a
pre-cleaned glass bottle with screw cap that prevents moisture from
entering.
6.7 Stock standard solutions (1.00 [micro]g/[micro]L)--Stock
standard solutions may be prepared from pure materials, or purchased as
certified solutions. Traceability must be to the National Institute of
Standards and Technology (NIST) or other national or international
standard, when available. Stock solution concentrations alternate to
those below may be used. Because of the toxicity of some of the
compounds, primary dilutions should be prepared in a hood, and a NIOSH/
MESA approved toxic gas respirator should be worn when high
concentrations of neat materials are handled. The following procedure
may be used to prepare standards from neat materials.
6.7.1 Prepare stock standard solutions by accurately weighing about
0.0100 g of pure material. Dissolve the material in pesticide quality
methanol or other suitable solvent and dilute to volume in a 10-mL
volumetric flask. Larger volumes may be used at the convenience of the
laboratory. When compound purity is assayed to be 96% or greater, the
weight may be used without correction to calculate the concentration of
the stock standard. Commercially prepared stock standards may be used at
any concentration if they are certified by the manufacturer or by an
independent source.
6.7.2 Unless stated otherwise in this method, store non-aqueous
standards in fluoropolymer-lined screw-cap, or heat-sealed, glass
containers, in the dark at -20 to -10 [deg]C. Store aqueous standards;
e.g., the aqueous LCS (section 8.4.1), in the dark at <= 6 [deg]C, but
do not freeze. Standards prepared by the laboratory may be stored for up
to one year, except when comparison with QC check standards indicates
that a standard has degraded or become more concentrated due to
evaporation, or unless the laboratory has data on file to prove
stability for a longer period. Commercially prepared standards may be
stored until the expiration date provided by the vendor, except when
comparison with QC check standards indicates that a standard has
degraded or become more concentrated due to evaporation, or unless the
laboratory has data from the vendor on file to prove stability for a
longer period.
6.8 Surrogate standard spiking solution.
6.8.1 Select a minimum of three surrogate compounds from Table 8
that most closely match the recovery of the analytes of interest. For
example, if all analytes tested are considered acids, use surrogates
that have similar chemical attributes. Other compounds may be used as
surrogates so long as they do not interfere in the analysis. If only one
or two analytes are determined, one or two surrogates may be used.
6.8.2 Prepare a solution containing each selected surrogate such
that the concentration in the sample would match the concentration in
the mid-point calibration standard. For example, if the midpoint of the
calibration is 100 [micro]g/L, prepare the spiking solution at a
concentration of 100 [micro]g/mL in methanol. Addition of 1.00 mL of
this solution to 1000 mL of sample will produce a concentration of 100
[micro]g/L of the surrogate. Alternate volumes and concentrations
appropriate to the response of the GC/MS instrument or for selective ion
monitoring (SIM) may be used, if desired. Store per section 6.7.2.
6.9 Internal standard spiking solution.
6.9.1 Select three or more internal standards similar in
chromatographic behavior to the analytes of interest. Internal standards
are listed in Table 8. Suggested internal standards are: 1,4-
dichlorobenzene-d4; naphthalene-d8; acenaphthene-
d10; phenanthrene-d10; chrysene-d12;
and perylene-d12. The laboratory must demonstrate that
measurement of the internal standards is not affected by method or
matrix interferences (see also section 7.3.4).
6.9.2 Prepare the internal standards at a concentration of 10 mg/mL
in methylene chloride or other suitable solvent. When 10 [micro]L of
this solution is spiked into a 1-mL extract, the concentration of the
internal standards will be 100 [micro]g/mL. A lower concentration
appropriate to the response of the GC/MS instrument or for SIM may be
used, if desired. Store per section 6.7.3.
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6.9.3 To assure accurate analyte identification, particularly when
SIM is used, it may be advantageous to include more internal standards
than those suggested in section 6.9.1. An analyte will be located most
accurately if its retention time relative to an internal standard is in
the range of 0.8 to 1.2.
6.10 DFTPP standard--Prepare a solution of DFTPP in methanol or
other suitable solvent such that 50 ng or less will be injected (see
section 13.2). An alternative concentration may be used to compensate
for specific injection volumes or to assure that the operating range of
the instrument is not exceeded, so long as the total injected is 50 ng
or less. Include benzidine and pentachlorophenol in this solution such
that <=100 ng of benzidine and <=50 ng of pentachlorophenol will be
injected.
6.11 Quality control check sample concentrate--See section 8.2.1.
6.12 GPC calibration solution.
6.12.1 Prepare a methylene chloride solution to contain corn oil,
bis(2-ethylhexyl) phthalate (BEHP), perylene, and sulfur at the
concentrations in section 6.12.2, or at concentrations appropriate to
the response of the detector.
Note: Sulfur does not readily dissolve in methylene chloride, but is
soluble in warm corn oil. The following procedure is suggested for
preparation of the solution.
6.12.2 Weigh 8 mg sulfur and 2.5 g corn oil into a 100-mL volumetric
flask and warm to dissolve the sulfur. Separately weigh 100 mg BEHP, 20
mg pentachlorophenol, and 2 mg perylene and add to flask. Bring to
volume with methylene chloride and mix thoroughly.
6.12.3 Store the solution in an amber glass bottle with a
fluoropolymer-lined screw cap at 0-6 [deg]C. Protect from light.
Refrigeration may cause the corn oil to precipitate. Before use, allow
the solution to stand at room temperature until the corn oil dissolves,
or warm slightly to aid in dissolution. Replace the solution every year,
or more frequently if the response of a component changes.
6.13 Sulfur removal--Copper foil or powder (bright, non-oxidized),
or tetrabutylammonium sulfite (TBA sulfite).
6.13.1 Copper foil, or powder--Fisher, Alfa Aesar 42455-18, 625
mesh, or equivalent. Cut copper foil into approximately 1-cm squares.
Copper must be activated before it may be used, as described below:
6.13.1.1 Place the quantity of copper needed for sulfur removal
(section 11.2.1.3) in a ground-glass-stoppered Erlenmeyer flask or
bottle. Cover the foil or powder with methanol.
6.13.1.2 Add HCl dropwise (0.5-1.0 mL) while swirling, until the
copper brightens.
6.13.1.3 Pour off the methanol/HCl and rinse 3 times with reagent
water to remove all traces of acid, then 3 times with acetone, then 3
times with hexane.
6.13.1.4 For copper foil, cover with hexane after the final rinse.
Store in a stoppered flask under nitrogen until used. For the powder,
dry on a rotary evaporator or under a stream of nitrogen. Store in a
stoppered flask under nitrogen until used. Inspect the copper foil or
powder before each use. It must have a bright, non-oxidized appearance
to be effective. Copper foil or powder that has oxidized may be
reactivated using the procedure described above.
6.13.2 Tetrabutylammonium sodium sulfite (TBA sodium sulfite).
6.13.2.1 Tetrabutylammonium hydrogen sulfate,
[CH3(CH2)3]4NHSO4.
6.13.2.2 Sodium sulfite, Na2SO3.
6.13.2.3 Dissolve approximately 3 g tetrabutylammonium hydrogen
sulfate in 100 mL of reagent water in an amber bottle with
fluoropolymer-lined screw cap. Extract with three 20-mL portions of
hexane and discard the hexane extracts.
6.13.2.4 Add 25 g sodium sulfite to produce a saturated solution.
Store at room temperature. Replace after 1 month.
6.14 DDT and endrin decomposition (breakdown) solution--Prepare a
solution containing endrin at a concentration of 1 [micro]g/mL and
4,4[min]-DDT at a concentration of 2 [micro]g/mL, in isooctane or
hexane. A 1-[micro]L injection of this standard will contain 1 nanogram
(ng) of endrin and 2 ng of DDT. The concentration of the solution may be
adjusted by the laboratory to accommodate other injection volumes such
that the same masses of the two analytes are introduced into the
instrument.
7. Calibration
7.1 Establish operating conditions equivalent to those in the
footnote to Table 4 or 5 for the base/neutral or acid fraction,
respectively. If a combined base/neutral/acid fraction will be analyzed,
use the conditions in the footnote to Table 4. Alternative temperature
program and flow rate conditions may be used. It is necessary to
calibrate the GC/MS for the analytes of interest (Section 1.3) only.
7.2 Internal standard calibration.
7.2.1 Prepare calibration standards for the analytes of interest and
surrogates at a minimum of five concentration levels by adding
appropriate volumes of one or more stock standards to volumetric flasks.
One of the calibration standards should be at a concentration at or
below the ML specified in Table 1, 2, or 3, or as specified by a
regulatory/control authority or in a permit. The ML value may be rounded
to a whole number that is more convenient for preparing the standard,
but must not exceed the ML in Table 1, 2, or 3 for those analytes which
list ML values. Alternatively, the laboratory may establish a laboratory
ML for each analyte based on the concentration in a
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nominal whole-volume sample that is equivalent to the concentration of
the lowest calibration standard in a series of standards produced in the
laboratory or obtained from a commercial vendor. The laboratory's ML
must not exceed the ML in Table 1, 2, or 3, and the resulting
calibration must meet the acceptance criteria in Section 7.2.3, based on
the RSD, RSE, or R\2\. The concentrations of the other calibration
standards should correspond to the expected range of concentrations
found in real samples or should define the working range of the GC/MS
system for full-scan and/or SIM operation, as appropriate. A minimum of
six concentration levels is required for a second order, non-linear
(e.g., quadratic; ax\2\ + bx + c = 0) calibration (section 7.2.3).
Calibrations higher than second order are not allowed. To each
calibration standard or standard mixture, add a known constant volume of
the internal standard solution (section 6.9), and dilute to volume with
methylene chloride.
Note: The large number of analytes in Tables 1 through 3 may not be
soluble or stable in a single solution; multiple solutions may be
required if a large number of analytes are to be determined
simultaneously.
7.2.1.1 Prior to analysis of the calibration standards, inject the
DFTPP standard (Section 6.10) and adjust the scan rate of the mass
spectrometer to produce a minimum of 5 mass spectra across the DFTPP GC
peak. Adjust instrument conditions until the DFTPP criteria in Table 9A
or 9B are met. Calculate peak tailing factors for benzidine and
pentachlorophenol. Calculation of the tailing factor is illustrated in
Figure 1. The tailing factor for benzidine and pentachlorophenol must be
<2; otherwise, adjust instrument conditions and either replace the
column or break off a short section of the front end of the column, and
repeat the test. Once the scan conditions are established, they must be
used for analyses of all standards, blanks, and samples.
Note: The DFTPP spectrum may be evaluated by summing the intensities
of the m/z's across the GC peak, subtracting the background at each m/z
in a region of the chromatogram within 20 scans of but not including any
part of, the DFTPP peak. The DFTPP spectrum may also be evaluated by
fitting a Gaussian to each m/z and using the intensity at the maximum
for each Gaussian or by integrating the area at each m/z and using the
integrated areas. Other means may be used for evaluation of the DFTPP
spectrum so long as the spectrum is not distorted to meet the criteria
in Table 9A or 9B.
7.2.1.2 Analyze the mid-point combined base/neutral and acid
calibration standard and enter or review the retention time, relative
retention time, mass spectrum, and quantitation m/z in the data system
for each analyte of interest, surrogate, and internal standard. If
additional analytes (Table 3) are to be quantified, include these
analytes in the standard. The mass spectrum for each analyte must be
comprised of a minimum of 2 m/z's (Tables 4 and 5); 3 to 5 m/z's assure
more reliable analyte identification. Suggested quantitation m/z's are
shown in Tables 4 and 5 as the primary m/z. If an interference occurs at
the primary m/z, use one of the secondary m/z's or an alternate m/z. A
single m/z only is required for quantitation.
7.2.1.3 For SIM operation, determine the analytes in each
descriptor, the quantitation m/z for each analyte (the quantitation m/z
can be the same as for full-scan operation; section 7.2.1.2), the dwell
time on each m/z for each analyte, and the beginning and ending
retention time for each descriptor. Analyze the verification standard in
scan mode to verify m/z's and establish retention times for the
analytes. There must be a minimum of two m/z's for each analyte to
assure analyte identification. To maintain sensitivity, the number of m/
z's in a descriptor should be limited. For example, for a descriptor
with 10 m/z's and a chromatographic peak width of 5 sec, a dwell time of
100 ms at each m/z would result in a scan time of 1 second and provide 5
scans across the GC peak. The quantitation m/z will usually be the most
intense peak in the mass spectrum. The quantitation m/z and dwell time
may be optimized for each analyte. The acquisition table used for SIM
must take into account the mass defect (usually less than 0.2 Dalton)
that can occur at each m/z monitored. Refer to the footnotes to Table 4
or 5 for establishing operating conditions and to section 7.2.1.1 for
establishing scan conditions.
7.2.1.4 For combined scan and SIM operation, set up the scan
segments and descriptors to meet requirements in sections 7.2.1.1-
7.2.1.3. Analyze unfamiliar samples in the scan mode to assure that the
analytes of interest are determined.
7.2.2 Analyze each calibration standard according to section 12 and
tabulate the area at the quantitation m/z against concentration for each
analyte of interest, surrogate, and internal standard. If an
interference is encountered, use a secondary m/z (Table 4 or 5) for
quantitation. Calculate a response factor (RF) for each analyte of
interest at each concentration using Equation 1.
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[GRAPHIC] [TIFF OMITTED] TR28AU17.014
where:
As = Area of the characteristic m/z for the analyte of
interest or surrogate.
Ais = Area of the characteristic m/z for the internal
standard.
Cis = Concentration of the internal standard ([micro]g/mL).
Cs = Concentration of the analyte of interest or surrogate
([micro]g/mL).
7.2. Calculate the mean (average) and relative standard deviation
(RSD) of the responses factors. If the RSD is less than 35%, the RF can
be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to fit a linear or
quadratic regression of response ratios, As/Ais, vs. concentration
ratios Cs/Cis. If used, the regression must be weighted inversely
proportional to concentration. The coefficient of determination (R\2\;
Reference 10) of the weighted regression must be greater than 0.920
(this value roughly corresponds to the RSD limit of 35%). Alternatively,
the relative standard error (Reference 11) may be used as an acceptance
criterion. As with the RSD, the RSE must be less than 35%. If an RSE
less than 35% cannot be achieved for a quadratic regression, system
performance is unacceptable and the system must be adjusted and re-
calibrated.
Note: Using capillary columns and current instrumentation, it is
quite likely that a laboratory can calibrate the target analytes in this
method and achieve a linearity metric (either RSD or RSE) well below
35%. Therefore, laboratories are permitted to use more stringent
acceptance criteria for calibration than described here, for example, to
harmonize their application of this method with those from other
sources.
7.3 Calibration verification--The RF or calibration curve must be
verified immediately after calibration and at the beginning of each 12-
hour shift, by analysis of a standard at or near the concentration of
the mid-point calibration standard (section 7.2.1). The standard(s) must
be obtained from a second manufacturer or a manufacturer's batch
prepared independently from the batch used for calibration. Traceability
must be to a national standard, when available. Include the surrogates
(section 6.8) in this solution. It is necessary to verify calibration
for the analytes of interest (section 1.3) only.
Note: The 12-hour shift begins after the DFTPP (section 13.1) and
DDT/endrin tests (if DDT and endrin are to be determined), and after
analysis of the calibration verification standard. The 12-hour shift
ends 12 hours later. The DFTPP, DDT/endrin, and calibration verification
tests are outside of the 12-hour shift.
7.3.1 Analyze the calibration verification standard(s) beginning in
section 12. Calculate the percent recovery of each analyte. Compare the
recoveries for the analytes of interest against the acceptance criteria
for recovery (Q) in Table 6, and the recoveries for the surrogates
against the acceptance criteria in Table 8. If recovery of the analytes
of interest and surrogates meet acceptance criteria, system performance
is acceptable and analysis of samples may continue. If any individual
recovery is outside its limit, system performance is unacceptable for
that analyte.
Note: The large number of analytes in Tables 6 and 8 present a
substantial probability that one or more will fail acceptance criteria
when all analytes are tested simultaneously.
7.3.2 When one or more analytes fail acceptance criteria, analyze a
second aliquot of the calibration verification standard and compare ONLY
those analytes that failed the first test (section 7.3.1) with their
respective acceptance criteria. If these analytes now pass, system
performance is acceptable and analysis of samples may continue. A repeat
failure of any analyte that failed the first test, however, will confirm
a general problem with the measurement system. If this occurs, repair
the system (section 7.2.1.1) and repeat the test (section 7.3.1), or
prepare a fresh calibration standard and repeat the test. If calibration
cannot be verified after maintenance or injection of the fresh
calibration standard, re-calibrate the instrument.
Note: If it is necessary to perform a repeat verification test
frequently; i.e., perform two tests in order to pass, it may be prudent
to perform two injections in succession and review the results, rather
than perform one injection, review the results, then perform the second
injection if results from the first injection fail. To maintain the
validity of the test and re-test, system maintenance and/or adjustment
is not permitted between the injections.
7.3.3 Many of the analytes in Table 3 do not have QC acceptance
criteria in Table 6, and some of the surrogates in Table 8 do not have
acceptance criteria. If calibration is to be verified and other QC tests
are to be performed for these analytes, acceptance criteria must be
developed and applied. EPA has provided guidance for development of QC
acceptance criteria (References 12 and 13). Alternatively, analytes that
do not have acceptance criteria in Table 6 or Table 8 may
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be based on laboratory control charts, or 60 to 140% may be used.
7.3.4 Internal standard responses--Verify that detector sensitivity
has not changed by comparing the response of each internal standard in
the calibration verification standard (section 7.3) to the response of
the respective internal standard in the midpoint calibration standard
(section 7.2.1). The peak areas or heights of the internal standards in
the calibration verification standard must be within 50% to 200% (1/2 to
2x) of their respective peak areas or heights in the mid-point
calibration standard. If not, repeat the calibration verification test
using a fresh calibration verification standard (7.3), or perform and
document system repair. Subsequent to repair, repeat the calibration
verification test (section 7.3.1). If the responses are still not within
50% to 200%, re-calibrate the instrument (section 7.2.2) and repeat the
calibration verification test.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality assurance program. The minimum requirements of this
program consist of an initial demonstration of laboratory capability and
ongoing analysis of spiked samples and blanks to evaluate and document
data quality (40 CFR 136.7). The laboratory must maintain records to
document the quality of data generated. Results of ongoing performance
tests are compared with established QC acceptance criteria to determine
if the results of analyses meet performance requirements of this method.
When results of spiked samples do not meet the QC acceptance criteria in
this method, a quality control check sample (laboratory control sample;
LCS) must be analyzed to confirm that the measurements were performed in
an in-control mode of operation. A laboratory may develop its own
performance criteria (as QC acceptance criteria), provided such criteria
are as or more restrictive than the criteria in this method.
8.1.1 The laboratory must make an initial demonstration of
capability (DOC) to generate acceptable precision and recovery with this
method. This demonstration is detailed in Section 8.2.
8.1.2 In recognition of advances that are occurring in analytical
technology, and to overcome matrix interferences, the laboratory is
permitted certain options (section 1.6 and 40 CFR 136.6(b)) to improve
separations or lower the costs of measurements. These options may
include alternate extraction, concentration, and cleanup procedures
(e.g., solid-phase extraction; rotary-evaporator concentration; column
chromatography cleanup), changes in column and type of mass spectrometer
(40 CFR 136.6(b)(4)(xvi)). Alternate determinative techniques, such as
substitution of spectroscopic or immunoassay techniques, and changes
that degrade method performance, are not allowed. If an analytical
technique other than GC/MS is used, that technique must have a
specificity equal to or greater than the specificity of GC/MS for the
analytes of interest. The laboratory is also encouraged to participate
in inter-comparison and performance evaluation studies (see section
8.10).
8.1.2.1 Each time a modification is made to this method, the
laboratory is required to repeat the procedure in section 8.2. If the
detection limit of the method will be affected by the change, the
laboratory must demonstrate that the MDLs (40 CFR part 136, appendix B)
are lower than one-third the regulatory compliance limit or the MDLs in
this method, whichever are greater. If calibration will be affected by
the change, the instrument must be recalibrated per section 7. Once the
modification is demonstrated to produce results equivalent or superior
to results produced by this method, that modification may be used
routinely thereafter, so long as the other requirements in this method
are met (e.g., matrix spike/matrix spike duplicate recovery and relative
percent difference).
8.1.2.1.1 If SPE, or another allowed method modification, is to be
applied to a specific discharge, the laboratory must prepare and analyze
matrix spike/matrix spike duplicate (MS/MSD) samples (section 8.3) and
LCS samples (section 8.4). The laboratory must include surrogates
(section 8.7) in each of the samples. The MS/MSD and LCS samples must be
fortified with the analytes of interest (Section 1.3). If the
modification is for nationwide use, MS/MSD samples must be prepared from
a minimum of nine different discharges (See section 8.1.2.1.2), and all
QC acceptance criteria in this method must be met. This evaluation only
needs to be performed once other than for the routine QC required by
this method (for example it could be performed by the vendor of the SPE
materials) but any laboratory using that specific material must have the
results of the study available. This includes a full data package with
the raw data that will allow an independent reviewer to verify each
determination and calculation performed by the laboratory (see section
8.1.2.2.5, items (a)-(q)).
8.1.2.1.2 Sample matrices on which MS/MSD tests must be performed
for nationwide use of an allowed modification:
(a) Effluent from a POTW.
(b) ASTM D5905 Standard Specification for Substitute Wastewater.
(c) Sewage sludge, if sewage sludge will be in the permit.
(d) ASTM D1141 Standard Specification for Substitute Ocean Water, if
ocean water will be in the permit.
(e) Untreated and treated wastewaters up to a total of nine matrix
types (see https://www.epa.gov/eg/industrial-effluent-guidelines
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for a list of industrial categories with existing effluent guidelines).
(i) At least one of the above wastewater matrix types must have at
least one of the following characteristics:
(A) Total suspended solids greater than 40 mg/L.
(B) Total dissolved solids greater than 100 mg/L.
(C) Oil and grease greater than 20 mg/L.
(D) NaCl greater than 120 mg/L.
(E) CaCO3 greater than 140 mg/L.
(ii) Results of MS/MSD tests must meet QC acceptance criteria in
Section 8.3.
(f) A proficiency testing (PT) sample from a recognized provider, in
addition to tests of the nine matrices (section 8.1.2.1.1).
8.1.2.2 The laboratory is required to maintain records of
modifications made to this method. These records include the following,
at a minimum:
8.1.2.2.1 The names, titles, and business street addresses,
telephone numbers, and email addresses, of the analyst(s) that performed
the analyses and modification, and of the quality control officer that
witnessed and will verify the analyses and modifications.
8.1.2.2.2 A list of analytes, by name and CAS Registry Number.
8.1.2.2.3 A narrative stating reason(s) for the modifications.
8.1.2.2.4 Results from all quality control (QC) tests comparing the
modified method to this method, including:
(a) Calibration (section 7).
(b) Calibration verification (section 7).
(c) Initial demonstration of capability (section 8.2).
(d) Analysis of blanks (section 8.5).
(e) Matrix spike/matrix spike duplicate analysis (section 8.3).
(f) Laboratory control sample analysis (section 8.4).
8.1.2.2.5 Data that will allow an independent reviewer to validate
each determination by tracing the instrument output (peak height, area,
or other signal) to the final result. These data are to include:
(a) Sample numbers and other identifiers.
(b) Extraction dates.
(c) Analysis dates and times.
(d) Analysis sequence/run chronology.
(e) Sample weight or volume (ssection 10).
(f) Extract volume prior to each cleanup step (sections 10 and 11).
(g) Extract volume after each cleanup step (section 11).
(h) Final extract volume prior to injection (sections 10 and 12).
(i) Injection volume (section 12.2.3).
(j) Sample or extract dilution (section 12.2.3.2).
(k) Instrument and operating conditions.
(l) Column (dimensions, material, etc).
(m) Operating conditions (temperature program, flow rate, etc).
(n) Detector (type, operating conditions, etc).
(o) Chromatograms, mass spectra, and other recordings of raw data.
(p) Quantitation reports, data system outputs, and other data to
link the raw data to the results reported.
(q) A written Standard Operating Procedure (SOP).
8.1.2.2.6 Each individual laboratory wishing to use a given
modification must perform the start-up tests in section 8.1.2 (e.g.,
DOC, MDL), with the modification as an integral part of this method
prior to applying the modification to specific discharges. Results of
the DOC must meet the QC acceptance criteria in Table 6 for the analytes
of interest (section 1.3), and the MDLs must be equal to or lower than
the MDLs in Tables 1, 2, or 3 for the analytes of interest.
8.1.3 Before analyzing samples, the laboratory must analyze a blank
to demonstrate that interferences from the analytical system, labware,
and reagents, are under control. Each time a batch of samples is
extracted or reagents are changed, a blank must be extracted and
analyzed as a safeguard against laboratory contamination. Requirements
for the blank are given in section 8.5.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze to
monitor and evaluate method and laboratory performance on the sample
matrix. The procedure for spiking and analysis is given in section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
analysis of a quality control check sample (laboratory control sample,
LCS; on-going precision and recovery sample, OPR) that the measurement
system is in control. This procedure is given in section 8.4.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is given in
section 8.9.
8.1.7 The large number of analytes tested in performance tests in
this method present a substantial probability that one or more will fail
acceptance criteria when many analytes are tested simultaneously, and a
re-test is allowed if this situation should occur. If, however,
continued re-testing results in further repeated failures, the
laboratory must document and report the failures (e.g., as qualifiers on
results), unless the failures are not required to be reported as
determined by the regulatory/control authority. Results associated with
a QC failure for an analyte regulated in a discharge cannot be used to
demonstrate regulatory compliance. QC failures do not relieve a
discharger or permittee of reporting timely results.
8.2 Initial demonstration of capability (DOC)--To establish the
ability to generate acceptable recovery and precision, the laboratory
must perform the DOC in sections
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8.2.1 through 8.2.6 for the analytes of interest. The laboratory must
also establish MDLs for the analytes of interest using the MDL procedure
at 40 CFR part 136, appendix B. The laboratory's MDLs must be equal to
or lower than those listed in Tables 1, 2, or 3 or lower than one third
the regulatory compliance limit, whichever is greater. For MDLs not
listed in Tables 4 and 5, the laboratory must determine the MDLs using
the MDL procedure at 40 CFR part 136, appendix B under the same
conditions used to determine the MDLs for the analytes listed in Tables
1, 2, and 3. All procedures used in the analysis, including cleanup
procedures, must be included in the DOC.
8.2.1 For the DOC, a QC check sample concentrate (LCS concentrate)
containing each analyte of interest (section 1.3) is prepared in a
water-miscible solvent. The QC check sample concentrate must be prepared
independently from those used for calibration, but may be from the same
source as the second-source standard used for calibration verification
(Section 7.3). The concentrate should produce concentrations of the
analytes of interest in water at the mid-point of the calibration range,
and may be at the same concentration as the LCS (section 8.4). Multiple
solutions may be required.
Note: QC check sample concentrates are no longer available from EPA.
8.2.2 Using a pipet or micro-syringe, prepare four LCSs by adding an
appropriate volume of the concentrate to each of four aliquots of
reagent water, and mix well. The volume of reagent water must be the
same as the volume that will be used for the sample, blank (section
8.5), and MS/MSD (section 8.3). A volume of 1-L and a concentration of
100 [micro]g/L were used to develop the QC acceptance criteria in Table
6. Also add an aliquot of the surrogate spiking solution (section 6.8)
to the reagent-water aliquots.
8.2.3 Extract and analyze the four LCSs according to the method
beginning in Section 10.
8.2.4 Calculate the average percent recovery (X) and the standard
deviation of the percent recovery (s) for each analyte using the four
results.
8.2.5 For each analyte, compare s and (X) with the corresponding
acceptance criteria for precision and recovery in Table 6. For analytes
in Table 3 not listed in Table 6, DOC QC acceptance criteria must be
developed by the laboratory. EPA has provided guidance for development
of QC acceptance criteria (References 12 and 13). Alternatively,
acceptance criteria for analytes not listed in Table 6 may be based on
laboratory control charts. If s and (X) for all analytes of interest
meet the acceptance criteria, system performance is acceptable and
analysis of blanks and samples may begin. If any individual s exceeds
the precision limit or any individual (X) falls outside the range for
recovery, system performance is unacceptable for that analyte.
Note: The large number of analytes in Tables 1-3 present a
substantial probability that one or more will fail at least one of the
acceptance criteria when many or all analytes are determined
simultaneously. Therefore, the analyst is permitted to conduct a ``re-
test'' as described in section 8.2.6.
8.2.6 When one or more of the analytes tested fail at least one of
the acceptance criteria, repeat the test for only the analytes that
failed. If results for these analytes pass, system performance is
acceptable and analysis of samples and blanks may proceed. If one or
more of the analytes again fail, system performance is unacceptable for
the analytes that failed the acceptance criteria. Correct the problem
and repeat the test (section 8.2). See section 8.1.7 for disposition of
repeated failures.
Note: To maintain the validity of the test and re-test, system
maintenance and/or adjustment is not permitted between this pair of
tests.
8.3 Matrix spike and matrix spike duplicate (MS/MSD)--The purpose of
the MS/MSD requirement is to provide data that demonstrate the
effectiveness of the method as applied to the samples in question by a
given laboratory, and both the data user (discharger, permittee,
regulated entity, regulatory/control authority, customer, other) and the
laboratory share responsibility for provision of such data. The data
user should identify the sample and the analytes of interest (section
1.3) to be spiked and provide sufficient sample volume to perform MS/MSD
analyses. The laboratory must, on an ongoing basis, spike at least 5% of
the samples in duplicate from each discharge being monitored to assess
accuracy (recovery and precision). If direction cannot be obtained from
the data user, the laboratory must spike at least one sample in
duplicate per extraction batch of up to 20 samples with the analytes in
Table 1. Spiked sample results should be reported only to the data user
whose sample was spiked, or as requested or required by a regulatory/
control authority, or in a permit.
8.3.1 If, as in compliance monitoring, the concentration of a
specific analyte will be checked against a regulatory concentration
limit, the concentration of the spike should be at that limit;
otherwise, the concentration of the spike should be one to five times
higher than the background concentration determined in section 8.3.2, at
or near the midpoint of the calibration range, or at the concentration
in the LCS (section 8.4) whichever concentration would be larger.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of the each analyte of interest. If necessary, prepare
a new check sample concentrate (section 8.2.1) appropriate for the
background
[[Page 279]]
concentration. Spike and analyze two additional sample aliquots, and
determine the concentration after spiking (A1 and
A2) of each analyte. Calculate the percent recoveries
(P1 and P2) as 100 (A1 - B)/T and 100
(A2 - B)/T, where T is the known true value of the spike.
Also calculate the relative percent difference (RPD) between the
concentrations (A1 and A2) as 200
[verbar]A1 - A2[verbar]/(A1 +
A2). If necessary, adjust the concentrations used to
calculate the RPD to account for differences in the volumes of the
spiked aliquots.
8.3.3 Compare the percent recoveries (P1 and
P2) and the RPD for each analyte in the MS/MSD aliquots with
the corresponding QC acceptance criteria in Table 6. A laboratory may
develop and apply QC acceptance criteria more restrictive than the
criteria in Table 6, if desired.
8.3.3.1 If any individual P falls outside the designated range for
recovery in either aliquot, or the RPD limit is exceeded, the result for
the analyte in the unspiked sample is suspect. See Section 8.1.7 for
disposition of failures.
8.3.3.2 The acceptance criteria in Table 6 were calculated to
include an allowance for error in measurement of both the background and
spike concentrations, assuming a spike to background ratio of 5:1. This
error will be accounted for to the extent that the spike to background
ratio approaches 5:1 (Reference 14) and is applied to spike
concentrations of 100 [micro]g/L and higher. If spiking is performed at
a concentration lower than 100 [micro]g/L, the laboratory must use the
QC acceptance criteria in Table 6, the optional QC acceptance criteria
calculated for the specific spike concentration in Table 7, or optional
in-house criteria (section 8.3.4). To use the acceptance criteria in
Table 7: (1) Calculate recovery (X[min]) using the equation in Table 7,
substituting the spike concentration (T) for C; (2) Calculate overall
precision (S[min]) using the equation in Table 7, substituting X[min]
for X; (3) Calculate the range for recovery at the spike concentration
as (100 X[min]/T) 2.44(100 S[min]/T)% (Reference
14). For analytes in Table 3 not listed in Table 6, QC acceptance
criteria must be developed by the laboratory. EPA has provided guidance
for development of QC acceptance criteria (References 12 and 13).
Alternatively, acceptance criteria may be based on laboratory control
charts.
8.3.4 After analysis of a minimum of 20 MS/MSD samples for each
target analyte and surrogate, and if the laboratory chooses to develop
and apply the optional in-house QC limits (Section 8.3.3), the
laboratory should calculate and apply the optional in-house QC limits
for recovery and RPD of future MS/MSD samples (Section 8.3). The QC
limits for recovery are calculated as the mean observed recovery 3 standard deviations, and the upper QC limit for RPD is
calculated as the mean RPD plus 3 standard deviations of the RPDs. The
in-house QC limits must be updated at least every two years and re-
established after any major change in the analytical instrumentation or
process. If in-house QC limits are developed, at least 80% of the
analytes tested in the MS/MSD must have in-house QC acceptance criteria
that are tighter than those in Table 6, and the remaining analytes
(those other than the analytes included in the 80%) must meet the
acceptance criteria in Table 6. If an in-house QC limit for the RPD is
greater than the limit in Table 6, then the limit in Table 6 must be
used. Similarly, if an in-house lower limit for recovery is below the
lower limit in Table 6, then the lower limit in Table 6 must be used,
and if an in-house upper limit for recovery is above the upper limit in
Table 6, then the upper limit in Table 6 must be used.
8.4 Laboratory control sample (LCS)--A QC check sample (laboratory
control sample, LCS; on-going precision and recovery sample, OPR)
containing each analyte of interest (Section 1.3) and surrogate must be
prepared and analyzed with each extraction batch of up to 20 samples to
demonstrate acceptable recovery of the analytes of interest from a clean
sample matrix.
8.4.1 Prepare the LCS by adding QC check sample concentrate (section
8.2.1) to reagent water. Include all analytes of interest (section 1.3)
in the LCS. The LCS may be the same sample prepared for the DOC (section
8.2.1). The volume of reagent water must be the same as the volume used
for the sample, blank (section 8.5), and MS/MSD (Section 8.3). Also add
an aliquot of the surrogate spiking solution (section 6.8). The
concentration of the analytes in reagent water should be the same as the
concentration in the DOC (section 8.2.2).
8.4.2 Analyze the LCS prior to analysis of field samples in the
extraction batch. Determine the concentration (A) of each analyte.
Calculate the percent recovery (PS) as 100 (A/T)%, where T is the true
value of the concentration in the LCS.
8.4.3 Compare the percent recovery (PS) for each analyte with its
corresponding QC acceptance criterion in Table 6. For analytes of
interest in Table 3 not listed in Table 6, use the QC acceptance
criteria developed for the LCS (section 8.4.5), or limits based on
laboratory control charts. If the recoveries for all analytes of
interest fall within their respective QC acceptance criteria, analysis
of blanks and field samples may proceed. If any individual PS falls
outside the range, proceed according to section 8.4.4.
Note: The large number of analytes in Tables 1-3 present a
substantial probability that one or more will fail the acceptance
criteria when all analytes are tested simultaneously. Because a re-test
is allowed in event of failure (sections 8.1.7 and 8.4.3), it may be
prudent to extract and analyze two LCSs together and evaluate results of
the second
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analysis against the QC acceptance criteria only if an analyte fails the
first test.
8.4.4 Repeat the test only for those analytes that failed to meet
the acceptance criteria (PS). If these analytes now pass, system
performance is acceptable and analysis of blanks and samples may
proceed. Repeated failure, however, will confirm a general problem with
the measurement system. If this occurs, repeat the test using a fresh
LCS (section 8.2.2) or an LCS prepared with a fresh QC check sample
concentrate (section 8.2.1), or perform and document system repair.
Subsequent to analysis of the LCS prepared with a fresh sample
concentrate, or to system repair, repeat the LCS test (section 8.4). If
failure of the LCS indicates a systemic problem with samples in the
batch, re-extract and re-analyze the samples in the batch. See section
8.1.7 for disposition of repeated failures.
Note: To maintain the validity of the test and re-test, system
maintenance and/or adjustment is not permitted between the pair of
tests.
8.4.5 After analysis of 20 LCS samples, and if the laboratory
chooses to develop and apply in-house QC limits, the laboratory should
calculate and apply in-house QC limits for recovery to future LCS
samples (section 8.4). Limits for recovery in the LCS should be
calculated as the mean recovery 3 standard
deviations. A minimum of 80% of the analytes tested for in the LCS must
have QC acceptance criteria tighter than those in Table 6, and the
remaining analytes (those other than the analytes included in the 80%)
must meet the acceptance criteria in Table 6. If an in-house lower limit
for recovery is lower than the lower limit in Table 6, the lower limit
in Table 6 must be used, and if an in-house upper limit for recovery is
higher than the upper limit in Table 6, the upper limit in Table 6 must
be used. Many of the analytes and surrogates do not contain acceptance
criteria. The laboratory should use 60-140% as interim acceptance
criteria for recoveries of spiked analytes and surrogates that do not
have recovery limits specified in Table 8, and at least 80% of the
surrogates must meet the 60-140% interim criteria until in-house LCS and
surrogate limits are developed. Alternatively, acceptance criteria for
analytes that do not have recovery limits in Table 6 may be based on
laboratory control charts. In-house QC acceptance criteria must be
updated at least every two years.
8.5 Blank--A blank must be extracted and analyzed with each
extraction batch to demonstrate that the reagents and equipment used for
preparation and analysis are free from contamination.
8.5.1 Spike the surrogates into the blank. Extract and concentrate
the blank using the same procedures and reagents used for the samples,
LCS, and MS/MSD in the batch. Analyze the blank immediately after
analysis of the LCS (section 8.4) and prior to analysis of the MS/MSD
and samples to demonstrate freedom from contamination.
8.5.2 If an analyte of interest is found in the blank: At a
concentration greater than the MDL for the analyte, at a concentration
greater than one-third the regulatory compliance limit, or at a
concentration greater than one-tenth the concentration in a sample in
the extraction batch, whichever is greater, analysis of samples must be
halted, and the problem corrected. If the contamination is traceable to
the extraction batch, samples affected by the blank must be re-extracted
and the extracts re-analyzed. If, however, continued re-testing results
in repeated blank contamination, the laboratory must document and report
the failures (e.g., as qualifiers on results), unless the failures are
not required to be reported as determined by the regulatory/control
authority. Results associated with blank contamination for an analyte
regulated in a discharge cannot be used to demonstrate regulatory
compliance. QC failures do not relieve a discharger or permittee of
reporting timely results.
8.6 Internal standards responses.
8.6.1 Calibration verification--The responses (GC peak heights or
areas) of the internal standards in the calibration verification must be
within 50% to 200% (1/2 to 2x) of their respective responses in the mid-
point calibration standard. If they are not, repeat the calibration
verification (Section 7.4) test or perform and document system repair.
Subsequent to repair, repeat the calibration verification. If the
responses are still not within 50% to 200%, re-calibrate the instrument
(Section 7) and repeat the calibration verification test.
8.6.2 Samples, blanks, LCSs, and MS/MSDs--The responses (GC peak
heights or areas) of each internal standard in each sample, blank, and
MS/MSD must be within 50% to 200% (1/2 to 2x) of its respective response
in the LCS for the extraction batch. If, as a group, all internal
standards are not within this range, perform and document system repair,
repeat the calibration verification (section 8.4), and re-analyze the
affected samples. If a single internal standard is not within the 50% to
200% range, use an alternate internal standard for quantitation of the
analyte referenced to the affected internal standard. It may be
necessary to use the data system to calculate a new response factor from
calibration data for the alternate internal standard/analyte pair. If an
internal standard fails the 50-200% criteria and no analytes are
detected in the sample, ignore the failure or report it if required by
the regulatory/control authority.
8.7 Surrogate recoveries--The laboratory must evaluate surrogate
recovery data in each sample against its in-house surrogate recovery
limits. The laboratory may use 60-
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140% as interim acceptance criteria for recoveries for surrogates not
listed in Table 8. At least 80% of the surrogates must meet the 60-140%
interim criteria until in-house limits are developed. Alternatively,
surrogate recovery limits may be developed from laboratory control
charts, but such limits must be at least as restrictive as those in
Table 8. Spike the surrogates into all samples, blanks, LCSs, and MS/
MSDs. Compare surrogate recoveries against the QC acceptance criteria in
Table 8 and/or those developed in section 7.3.3 or 8.4.5. If any
recovery fails its criteria, attempt to find and correct the cause of
the failure. See section 8.1.7 for disposition of failures.
8.8 DDT and endrin decomposition (breakdown)--If DDT and/or endrin
are to be analyzed using this method, the DDT/endrin decomposition test
in section 13.8 must be performed to reliably quantify these two
pesticides.
8.9 As part of the QC program for the laboratory, control charts or
statements of accuracy for wastewater samples must be assessed and
records maintained (40 CFR 136.7(c)(1)(viii)). After analysis of five or
more spiked wastewater samples as in section 8.3, calculate the average
percent recovery (PX) and the standard deviation of the
percent recovery (sp). Express the accuracy assessment as a percent
interval from PX -2sp to PX +2sp. For example, if
PX = 90% and sp = 10%, the accuracy interval is expressed as
70-110%. Update the accuracy assessment for each analyte on a regular
basis (e.g., after each 5-10 new accuracy measurements). If desired,
statements of accuracy for laboratory performance, independent of
performance on samples, may be developed using LCSs.
8.10 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of environmental measurements. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevant performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Collect samples as grab samples in amber or clear glass bottles,
or in refrigerated bottles using automatic sampling equipment. If clear
glass is used, protect samples from light. Collect 1-L of ambient
waters, effluents, and other aqueous samples. If the sensitivity of the
analytical system is sufficient, a smaller volume (e.g., 250 mL), but no
less than 100 mL, may be used. Conventional sampling practices
(Reference 15) should be followed, except that the bottle must not be
pre-rinsed with sample before collection. Automatic sampling equipment
must be as free as possible of polyvinyl chloride or other tubing or
other potential sources of contamination. If needed, collect additional
sample(s) for the MS/MSD (section 8.3).
9.2 Ice or refrigerate samples at <=6 [deg]C from the time of
collection until extraction, but do not freeze. If residual chlorine is
present, add 80 mg of sodium thiosulfate per liter of sample and mix
well. Any method suitable for field use may be employed to test for
residual chlorine (Reference 16). Add more sodium sulfate if 80 mg/L is
insufficient but do not add excess sodium thiosulfate. If sodium
thiosulfate interferes in the determination of the analytes, an
alternate preservative (e.g., ascorbic acid or sodium sulfite) may be
used. If preservative has been added, shake the sample vigorously for
one minute. Maintain the hermetic seal on the sample bottle until time
of analysis.
9.3 All samples must be extracted within 7 days of collection and
sample extracts must be analyzed within 40 days of extraction.
10. Extraction
10.1 This section contains procedures for separatory funnel liquid-
liquid extraction (SFLLE) and continuous liquid-liquid extraction
(CLLE). SFLLE is faster, but may not be as effective as CLLE for
recovery of polar analytes such as phenol. SFLLE is labor intensive and
may result in formation of emulsions that are difficult to break. CLLE
is less labor intensive, avoids emulsion formation, but requires more
time (18-24 hours) and more hood space, and may require more solvent.
The procedures assume base-neutral extraction followed by acid
extraction. For some matrices and analytes of interest, improved results
may be obtained by acid-neutral extraction followed by base extraction.
A single acid or base extraction may also be performed. If an extraction
scheme alternate to base-neutral followed by acid extraction is used,
all QC tests must be performed and all QC acceptance criteria must be
met with that extraction scheme as an integral part of this method.
Solid-phase extraction (SPE) may be used provided requirements in
section 8.1.2 are met.
10.2 Separatory funnel liquid-liquid extraction (SFLLE) and extract
concentration.
10.2.1 The SFLLE procedure below assumes a sample volume of 1 L.
When a different sample volume is extracted, adjust the volume of
methylene chloride accordingly.
10.2.2 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Pour the entire sample into the
separatory funnel. Pipet the surrogate standard spiking solution
(section 6.8) into the separatory funnel. If the sample will be used for
the LCS or MS or MSD, pipet the
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appropriate check sample concentrate (section 8.2.1 or 8.3.2) into the
separatory funnel. Mix well. Check the pH of the sample with wide-range
pH paper and adjust to pH 11-13 with sodium hydroxide solution.
10.2.3 Add 60 mL of methylene chloride to the sample bottle, seal,
and shake for approximately 30 seconds to rinse the inner surface.
Transfer the solvent to the separatory funnel and extract the sample by
shaking the funnel for two minutes with periodic venting to release
excess pressure. Allow the organic layer to separate from the water
phase for a minimum of 10 minutes. If the emulsion interface between
layers is more than one-third the volume of the solvent layer, the
analyst must employ mechanical techniques to complete the phase
separation. The optimum technique depends upon the sample, but may
include stirring, filtration of the emulsion through glass wool or
phase-separation paper, salting, centrifugation, or other physical
methods. Collect the methylene chloride extract in a flask. If the
emulsion cannot be broken (recovery of <80% of the methylene chloride),
transfer the sample, solvent, and emulsion into a continuous extractor
and proceed as described in section 10.3.
10.2.4 Add a second 60-mL volume of methylene chloride to the sample
bottle and repeat the extraction procedure a second time, combining the
extracts in the Erlenmeyer flask. Perform a third extraction in the same
manner.
10.2.5 Adjust the pH of the aqueous phase to less than 2 using
sulfuric acid. Serially extract the acidified aqueous phase three times
with 60 mL aliquots of methylene chloride. Collect and combine the
extracts in a flask in the same manner as the base/neutral extracts.
Note: Base/neutral and acid extracts may be combined for
concentration and analysis provided all QC tests are performed and all
QC acceptance criteria met for the analytes of interest with the
combined extract as an integral part of this method, and provided that
the analytes of interest are as reliably identified and quantified as
when the extracts are analyzed separately. If doubt exists as to whether
identification and quantitation will be affected by use of a combined
extract, the fractions must be analyzed separately.
10.2.6 For each fraction or the combined fractions, assemble a
Kuderna-Danish (K-D) concentrator by attaching a 10-mL concentrator tube
to a 500-mL evaporative flask. Other concentration devices or techniques
may be used in place of the K-D concentrator so long as the requirements
in section 8.2 are met.
10.2.7 For each fraction or the combined fractions, pour the extract
through a solvent-rinsed drying column containing about 10 cm of
anhydrous sodium sulfate, and collect the extract in the K-D
concentrator. Rinse the Erlenmeyer flask and column with 20-30 mL of
methylene chloride to complete the quantitative transfer.
10.2.8 Add one or two clean boiling chips and attach a three-ball
Snyder column to the evaporative flask for each fraction (section
10.2.7). Pre-wet the Snyder column by adding about 1 mL of methylene
chloride to the top. Place the K-D apparatus on a hot water bath (60-65
[deg]C) so that the concentrator tube is partially immersed in the hot
water, and the entire lower rounded surface of the flask is bathed with
hot vapor. Adjust the vertical position of the apparatus and the water
temperature as required to complete the concentration in 15-20 minutes.
At the proper rate of distillation, the balls of the column will
actively chatter but the chambers will not flood with condensed solvent.
When the apparent volume of liquid reaches 1 mL or other determined
amount, remove the K-D apparatus from the water bath and allow to drain
and cool for at least 10 minutes. Remove the Snyder column and rinse the
flask and its lower joint into the concentrator tube with 1-2 mL of
methylene chloride. A 5-mL syringe is recommended for this operation. If
the sample will be cleaned up, reserve the K-D apparatus for
concentration of the cleaned up extract. Adjust the volume to 5 mL with
methylene chloride and proceed to section 11 for cleanup; otherwise,
further concentrate the extract for GC/MS analysis per section 10.2.9 or
10.2.10.
10.2.9 Micro Kuderna-Danish concentration--Add another one or two
clean boiling chips to the concentrator tube for each fraction and
attach a two-ball micro-Snyder column. Pre-wet the Snyder column by
adding about 0.5 mL of methylene chloride to the top. Place the K-D
apparatus on a hot water bath (60-65 [deg]C) so that the concentrator
tube is partially immersed in hot water. Adjust the vertical position of
the apparatus and the water temperature as required to complete the
concentration in 5-10 minutes. At the proper rate of distillation the
balls of the column will actively chatter but the chambers will not
flood with condensed solvent. When the apparent volume of liquid reaches
about 1 mL or other determined amount, remove the K-D apparatus from the
water bath and allow it to drain and cool for at least 10 minutes.
Remove the Snyder column and rinse the flask and its lower joint into
the concentrator tube with approximately 0.2 mL of or methylene
chloride. Adjust the final volume to 1.0 mL or a volume appropriate to
the sensitivity desired (e.g., to meet lower MDLs or for selected ion
monitoring). Record the volume, stopper the concentrator tube and store
refrigerated if further processing will not be performed immediately. If
the extracts will be stored longer than two days, they should be
transferred to
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fluoropolymer-lined screw-cap vials and labeled base/neutral or acid
fraction as appropriate. Mark the level of the extract on the vial so
that solvent loss can be detected.
10.2.10 Nitrogen evaporation and solvent exchange--Extracts may be
concentrated for analysis using nitrogen evaporation in place of micro
K-D concentration (section 10.2.9). Extracts that have been cleaned up
using sulfur removal (section 11.2) and are ready for analysis are
exchanged into methylene chloride.
10.2.10.1 Transfer the vial containing the sample extract to the
nitrogen evaporation (blowdown) device (section 5.8). Lower the vial
into the water bath and begin concentrating. If the more volatile
analytes (section 1.2) are to be concentrated, use room temperature for
concentration; otherwise, a slightly elevated (e.g., 30-45 [deg]C) may
be used. During the solvent evaporation process, keep the solvent level
below the water level of the bath and do not allow the extract to become
dry. Adjust the flow of nitrogen so that the surface of the solvent is
just visibly disturbed. A large vortex in the solvent may cause analyte
loss.
10.2.10.2 Extracts to be solvent exchanged--When the volume of the
liquid is approximately 200 [micro]L, add 2 to 3 mL of methylene
chloride and continue concentrating to approximately 100 [micro]L.
Repeat the addition of solvent and concentrate once more. Adjust the
final extract volume to be consistent with the volume extracted and the
sensitivity desired.
10.2.10.3 For extracts that have been cleaned up by GPC and that are
to be concentrated to a nominal volume of 1 mL, adjust the final volume
to compensate the GPC loss. For a 50% GPC loss, concentrate the extract
to 1/2000 of the volume extracted. For example, if the volume extracted
is 950 mL, adjust the final volume to 0.48 mL. For extracts that have
not been cleaned up by GPC and are to be concentrated to a nominal
volume of 1.0 mL, adjust the final extract volume to 1/1000 of the
volume extracted. For example, if the volume extracted is 950 mL, adjust
the final extract volume to 0.95 mL. Alternative means of compensating
the loss during GPC are acceptable so long as they produce results as
accurate as results produced using the procedure detailed in this
Section. An alternative final volume may be used, if desired, and the
calculations adjusted accordingly.
Note: The difference in the volume fraction for an extract cleaned
up by GPC accounts for the loss in GPC cleanup. Also, by preserving the
ratio between the volume extracted and the final extract volume, the
concentrations and detection limits do not need to be adjusted for
differences in the volume extracted and the extract volume.
10.2.11 Transfer the concentrated extract to a vial with
fluoropolymer-lined cap. Seal the vial and label with the sample number.
Store in the dark at room temperature until ready for GC analysis. If GC
analysis will not be performed on the same day, store the vial in the
dark at <=6 [deg]C. Analyze the extract by GC/MS per the procedure in
section 12.
10.2.12 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to an appropriately sized
graduated cylinder. For sample volumes on the order of 1000 mL, record
the sample volume to the nearest 10 mL; for sample volumes on the order
of 100 mL, record the volume to the nearest 1 mL. Sample volumes may
also be determined by weighing the container before and after filling to
the mark with water.
10.3 Continuous liquid/liquid extraction (CLLE).
Note: With CLLE, phenol, 2,4-dimethyl phenol, and some other
analytes may be preferentially extracted into the base-neutral fraction.
Determine an analyte in the fraction in which it is identified and
quantified most reliably. Also, the short-chain phthalate esters (e.g.,
dimethyl phthalate, diethyl phthalate) and some other compounds may
hydrolyze during prolonged exposure to basic conditions required for
continuous extraction, resulting in low recovery of these analytes. When
these analytes are of interest, their recovery may be improved by
performing the acid extraction first.
10.3.1 Use CLLE when experience with a sample from a given source
indicates an emulsion problem, or when an emulsion is encountered during
SFLLE. CLLE may be used for all samples, if desired.
10.3.2 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Check the pH of the sample with
wide-range pH paper and adjust to pH 11-13 with sodium hydroxide
solution. Transfer the sample to the continuous extractor. Pipet
surrogate standard spiking solution (section 6.8) into the sample. If
the sample will be used for the LCS or MS or MSD, pipet the appropriate
check sample concentrate (section 8.2.1 or 8.3.2) into the extractor.
Mix well. Add 60 mL of methylene chloride to the sample bottle, seal,
and shake for 30 seconds to rinse the inner surface. Transfer the
solvent to the extractor.
10.3.3 Repeat the sample bottle rinse with an additional 50-100 mL
portion of methylene chloride and add the rinse to the extractor.
10.3.4 Add a suitable volume of methylene chloride to the distilling
flask (generally 200-500 mL), add sufficient reagent water to ensure
proper operation, and extract for 18-24 hours. A shorter or longer
extraction time may be used if all QC acceptance criteria are met. Test
and, if necessary, adjust the pH of the water during the second or third
hour of the extraction. After extraction, allow the apparatus to cool,
then detach the distilling flask. Dry, concentrate, and seal the extract
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per sections 10.2.6 through 10.2.11. See the note at section 10.2.5
regarding combining extracts of the base/neutral and acid fractions.
10.3.5 Charge the distilling flask with methylene chloride and
attach it to the continuous extractor. Carefully, while stirring, adjust
the pH of the aqueous phase to less than 2 using sulfuric acid. Extract
for 18-24 hours. A shorter or longer extraction time may be used if all
QC acceptance criteria are met. Test and, if necessary, adjust the pH of
the water during the second or third hour of the extraction. After
extraction, allow the apparatus to cool, then detach the distilling
flask. Dry, concentrate, and seal the extract per sections 10.2.6
through 10.2.11. Determine the sample volume per section 10.2.12.
11. Extract Cleanup
Note: Cleanup may not be necessary for relatively clean samples
(e.g., treated effluents, groundwater, drinking water). If particular
circumstances require the use of a cleanup procedure, the laboratory may
use any or all of the procedures below or any other appropriate
procedure. Before using a cleanup procedure, the laboratory must
demonstrate that the requirements of section 8.1.2 can be met using the
cleanup procedure as an integral part of this method.
11.1 Gel permeation chromatography (GPC).
11.1.1 Calibration.
11.1.1.1 Load the calibration solution (section 6.12) into the
sample loop.
11.1.1.2 Inject the calibration solution and record the signal from
the detector. The elution pattern will be corn oil, bis(2-ethylhexyl)
phthalate, pentachlorophenol, perylene, and sulfur.
11.1.1.3 Set the ``dump time'' to allow 85% removal of
the corn oil and 85% collection of the phthalate.
11.1.1.4 Set the ``collect time'' to the peak minimum between
perylene and sulfur.
11.1.1.5 Verify calibration with the calibration solution after
every 20 or fewer extracts. Calibration is verified if the recovery of
the pentachlorophenol is greater than 85%. If calibration is not
verified, recalibrate using the calibration solution, and re-extract and
clean up the preceding extracts using the calibrated GPC system.
11.1.2 Extract cleanup--GPC requires that the column not be
overloaded. The column specified in this method is designed to handle a
maximum of 0.5 g of high molecular weight material in a 5-mL extract. If
the extract is known or expected to contain more than 0.5 g, the extract
is split into fractions for GPC and the fractions are combined after
elution from the column. The solids content of the extract may be
obtained gravimetrically by evaporating the solvent from a 50-[micro]L
aliquot.
11.1.2.1 Filter the extract or load through the filter holder to
remove particulates. Load the extract into the sample loop. The maximum
capacity of the column is 0.5-1.0 g. If necessary, split the extract
into multiple aliquots to prevent column overload.
11.1.2.2 Elute the extract using the calibration data determined in
Section 11.1.1. Collect the eluate in the K-D apparatus reserved in
section 10.2.8.
11.1.3 Concentrate the cleaned up extract per sections 10.2.8 and
10.2.9 or 10.2.10.
11.1.4 Rinse the sample loading tube thoroughly with methylene
chloride between extracts to prepare for the next sample.
11.1.5 If a particularly dirty extract is encountered, run a
methylene chloride blank through the system to check for carry-over.
11.2 Sulfur removal.
Note: Separate procedures using copper or TBA sulfite are provided
in this section for sulfur removal. They may be used separately or in
combination, if desired.
11.2.1 Removal with copper (Reference 17).
Note: If an additional compound (Table 3) is to be determined;
sulfur is to be removed; copper will be used for sulfur removal; and a
sulfur matrix is known or suspected to be present, the laboratory must
demonstrate that the additional compound can be successfully extracted
and treated with copper in the sulfur matrix. Some of the additional
compounds (Table 3) are known not to be amenable to sulfur removal with
copper (e.g., Atrazine and Diazinon).
11.2.1.1 Quantitatively transfer the extract from section 10.2.8 to
a 40- to 50-mL flask or bottle. If there is evidence of water in the
concentrator tube after the transfer, rinse the tube with small portions
of hexane:acetone (40:60) and add to the flask or bottle. Mark and set
aside the concentrator tube for use in re-concentrating the extract.
11.2.1.2 Add 10-20 g of granular anhydrous sodium sulfate to the
flask. Swirl to dry the extract.
11.2.1.3 Add activated copper (section 6.13.1.4) and allow to stand
for 30--60 minutes, swirling occasionally. If the copper does not remain
bright, add more and swirl occasionally for another 30-60 minutes.
11.2.1.4 After drying and sulfur removal, quantitatively transfer
the extract to a nitrogen-evaporation vial or tube and proceed to
section 10.2.10 for nitrogen evaporation and solvent exchange, taking
care to leave the sodium sulfate and copper in the flask.
11.2.2 Removal with TBA sulfite.
11.2.2.1 Using small volumes of hexane, quantitatively transfer the
extract to a 40- to 50-mL centrifuge tube with fluoropolymer-lined screw
cap.
11.2.2.2 Add 1-2 mL of TBA sulfite reagent (section 6.13.2.4), 2-3
mL of 2-propanol, and approximately 0.7 g of sodium sulfite (section
6.13.2.2) crystals to the tube. Cap and
[[Page 285]]
shake for 1-2 minutes. If the sample is colorless or if the initial
color is unchanged, and if clear crystals (precipitated sodium sulfite)
are observed, sufficient sodium sulfite is present. If the precipitated
sodium sulfite disappears, add more crystalline sodium sulfite in
approximately 0.5 g portions until a solid residue remains after
repeated shaking.
11.2.2.3 Add 5-10 mL of reagent water and shake for 1-2 minutes.
Centrifuge to settle the solids.
11.2.2.4 Quantitatively transfer the hexane (top) layer through a
small funnel containing a few grams of granular anhydrous sodium sulfate
to a nitrogen-evaporation vial or tube and proceed to section 10.2.10
for nitrogen evaporation and solvent exchange.
12. Gas Chromatography/Mass Spectrometry
12.1 Establish the operating conditions in Table 4 or 5 for analysis
of a base/neutral or acid extract, respectively. For analysis of a
combined extract (section 10.2.5, note), use the operating conditions in
Table 4 MDLs and MLs for the analytes are given in Tables 1, 2, and 3.
Retention times for many of the analytes are given in Tables 4 and 5.
Examples of the separations achieved are shown in Figure 2 for the
combined extract. Alternative columns or chromatographic conditions may
be used if the requirements of section 8.2 are met. Verify system
performance per section 13.
12.2 Analysis of a standard or extract.
12.2.1 Bring the standard or concentrated extract (section 10.2.9 or
10.2.11) to room temperature and verify that any precipitate has
redissolved. Verify the level on the extract and bring to the mark with
solvent if required.
12.2.2 Add the internal standard solution (section 6.9) to the
extract. Mix thoroughly.
12.2.3 Inject an appropriate volume of the sample extract or
standard solution using split, splitless, solvent purge, large-volume,
or on-column injection. If the sample is injected manually the solvent-
flush technique should be used. The injection volume depends upon the
technique used and the ability to meet MDLs or reporting limits for
regulatory compliance. Injected volumes must be the same for standards
and sample extracts. Record the volume injected to two significant
figures.
12.2.3.1 Start the GC column oven program upon injection. Start MS
data collection after the solvent peak elutes. Stop data collection
after benzo(ghi)perylene elutes for the base/neutral or combined
fractions, or after pentachlorophenol elutes for the acid fraction.
Return the column to the initial temperature for analysis of the next
standard solution or extract.
12.2.3.2 If the concentration of any analyte of interest exceeds the
calibration range, either extract and analyze a smaller sample volume,
or dilute and analyze the diluted extract after bringing the
concentrations of the internal standards to the levels in the undiluted
extract.
12.2.4 Perform all qualitative and quantitative measurements as
described in Sections 14 and 15. When standards and extracts are not
being used for analyses, store them refrigerated at <=6 [deg]C protected
from light in screw-cap vials equipped with un-pierced fluoropolymer-
lined septa.
13. Performance Tests
13.1 At the beginning of each 12-hour shift during which standards
or extracts will be analyzed, perform the tests in sections 13.2-13.4 to
verify system performance. If an extract is concentrated for greater
sensitivity (e.g., by SIM), all tests must be performed at levels
consistent with the reduced extract volume.
13.2 DFTPP--Inject the DFTPP standard (section 6.10) and verify that
the criteria for DFTPP in section 7.2.1.1 and Table 9A (Reference 18)
for a quadrupole MS, or Table 9B (Reference 19) for a time-of-flight MS,
are met.
13.3 GC resolution--The resolution should be verified on the mid-
point concentration of the initial calibration as well as the laboratory
designated continuing calibration verification level if closely eluting
isomers are to be reported (e.g., benzo(b)fluoranthene and
benzo(k)fluoranthene). Sufficient gas chromatographic resolution is
achieved if the height of the valley between two isomer peaks is less
than 50% of the average of the two peak heights.
13.4 Calibration verification--Verify calibration per sections 7.3
and Table 6.
13.5 Peak tailing--Verify the tailing factor specifications are met
per Section 7.2.1.1.
13.6 Laboratory control sample and blank--Analyze the extracts of
the LCS and blank at the beginning of analyses of samples in the
extraction batch (section 3.1). The LCS must meet the requirements in
section 8.4, and the blank must meet the requirements in section 8.5
before sample extracts may be analyzed.
13.7 Analysis of DFTPP, the DDT/Endrin decomposition test (if used),
the LCS, and the blank are outside of the 12-hour analysis shift
(section 3.1). The total time for DFTPP, DDT/Endrin, the LCS, the blank,
and the 12-hour shift must not exceed 15 hours.
13.8 Decomposition of DDT and endrin--If DDT and/or endrin are to be
determined, this test must be performed prior to calibration
verification (section 13.4). The QC acceptance criteria (section 13.8.3)
must be met before analyzing samples for DDE and/or Endrin. DDT
decomposes to DDE and DDD. Endrin decomposes to endrin aldehyde and
endrin ketone.
13.8.1 Inject 1 [micro]L of the DDT and endrin decomposition
solution (section 6.14). As
[[Page 286]]
noted in section 6.14, other injection volumes may be used as long as
the concentrations of DDT and endrin in the solution are adjusted to
introduce the masses of the two analytes into the instrument that are
listed in section 6.14.
13.8.2 Measure the areas of the peaks for DDT, DDE, DDD, Endrin,
Endrin aldehyde, and Endrin ketone. Calculate the percent breakdown as
shown in the equations below:
[GRAPHIC] [TIFF OMITTED] TR28AU17.015
13.8.3 Both the % breakdown of DDT and of Endrin must be less than
20%, otherwise the system is not performing acceptably for DDT and
endrin. In this case, repair the GC column system that failed and repeat
the performance tests (sections 13.2 to 13.6) until the specification is
met.
Note: DDT and endrin decomposition are usually caused by
accumulation of particulates in the injector and in the front end of the
column. Cleaning and silanizing the injection port liner, and breaking
off a short section of the front end of the column will usually
eliminate the decomposition problem. Either of these corrective actions
may affect retention times, GC resolution, and calibration linearity.
14. Qualitative Identification
14.1 Identification is accomplished by comparison of data from
analysis of a sample or blank with data stored in the GC/MS data system
(sections 5.6.5 and 7.2.1.2). Identification of an analyte is confirmed
per sections 14.1.1 through 14.1.4.
14.1.1 The signals for the quantitation and secondary m/z's stored
in the data system for each analyte of interest must be present and must
maximize within the same two consecutive scans.
14.1.2 The retention time for the analyte should be within 10 seconds of the analyte in the calibration
verification run at the beginning of the shift (section 7.3 or 13.4).
Note: Retention time windows other than 10
seconds may be appropriate depending on the performance of the gas
chromatograph or observed retention time drifts due to certain types of
matrix effects. Relative retention time (RRT) may be used as an
alternative to absolute retention times if retention time drift is a
concern. RRT is a unitless quantity (see Sec. 22.2), although some
procedures refer to ``RRT units'' in providing the specification for the
agreement between the RRT values in the sample and the calibration
verification or other standard. When significant retention time drifts
are observed, dilutions or spiked samples may help the analyst determine
the effects of the matrix on elution of the target analytes and to
assist in qualitative identification.
14.1.3 Either the background corrected EICP areas, or the corrected
relative intensities of the mass spectral peaks at the GC peak maximum,
must agree within 50% to 200% (1/2 to 2 times) for the quantitation and
secondary m/z's in the reference mass spectrum stored in the data system
(section 7.2.1.2), or from a reference library. For example, if a peak
has an intensity of 20% relative to the base peak, the analyte is
identified if the intensity of the peak in the sample is in the range of
10% to 40% of the base peak. If identification is ambiguous, an
experienced spectrometrist (section 1.7) must determine the presence or
absence of the compound.
14.2 Structural isomers that produce very similar mass spectra
should be identified as individual isomers if they have sufficiently
different gas chromatographic retention times. Sufficient gas
chromatographic resolution is achieved if the height of the valley
between two isomer peaks is less than 50% of the average of the two peak
heights. Otherwise, structural isomers are identified as isomeric pairs.
15. Calculations
15.1 When an analyte has been identified, quantitation of that
analyte is based on the integrated abundance from the EICP of the
primary characteristic m/z in Table 4 or 5. Calculate the concentration
in the extract
[[Page 287]]
using the response factor (RF) determined in Section 7.2.2 and Equation
2. If the concentration of an analyte exceeds the calibration range,
dilute the extract by the minimum amount to bring the concentration into
the calibration range, and re-analyze the extract. Determine a dilution
factor (DF) from the amount of the dilution. For example, if the extract
is diluted by a factor of 2, DF = 2.
[GRAPHIC] [TIFF OMITTED] TR28AU17.016
where:
Cex = Concentration of the analyte in the extract, in
[micro]g/mL, and the other terms are as defined in section
7.2.2.
Calculate the concentration of the analyte in the sample using the
concentration in the extract, the extract volume, the sample volume, and
the dilution factor, per Equation 3:
[GRAPHIC] [TIFF OMITTED] TR28AU17.017
where:
Csamp = Concentration of the analyte in the sample
Cex = Concentration of the analyte in the extract, in
[micro]g/mL
Vex = Volume of extract (mL)
Vs = Volume of sample (L)
DF = Dilution factor
15.2 Reporting of results. As noted in section 1.4.1, EPA has
promulgated this method at 40 CFR part 136 for use in wastewater
compliance monitoring under the National Pollutant Discharge Elimination
System (NPDES). The data reporting practices described here are focused
on such monitoring needs and may not be relevant to other uses of the
method.
15.2.1 Report results for wastewater samples in [micro]g/L without
correction for recovery. (Other units may be used if required by in a
permit.) Report all QC data with the sample results.
15.2.2 Reporting level. Unless specified otherwise by a regulatory
authority or in a discharge permit, results for analytes that meet the
identification criteria are reported down to the concentration of the ML
established by the laboratory through calibration of the instrument (see
section 7.3.2 and the glossary for the derivation of the ML). EPA
considers the terms ``reporting limit,'' ``quantitation limit,'' ``limit
of quantitation,'' and ``minimum level'' to be synonymous.
15.2.2.1 Report a result for each analyte in each field sample or QC
standard at or above the ML to 3 significant figures. Report a result
for each analyte found in each field sample or QC standard below the ML
as ``ML'' where ML is the concentration of the analyte at the ML, or as
required by the regulatory/control authority or permit. Report a result
for each analyte in a blank at or above the MDL to 2 significant
figures. Report a result for each analyte found in a blank below the MDL
as ``MDL,'' where MDL is the concentration of the analyte at the MDL, or
as required by the regulatory/control authority or permit.
15.2.2.2 In addition to reporting results for samples and blanks
separately, the concentration of each analyte in a blank associated with
the sample may be subtracted from the result for that sample, but only
if requested or required by a regulatory authority or in a permit. In
this case, both the sample result and the blank results must be reported
together.
15.2.2.3 Report a result for an analyte found in a sample or extract
that has been diluted at the least dilute level at which the area at the
quantitation m/z is within the calibration range (i.e., above the ML for
the analyte) and the MS/MSD recovery and RPD are within their respective
QC acceptance criteria (Table 6). This may require reporting results for
some analytes from different analyses.
15.2.3 Results from tests performed with an analytical system that
is not in control (i.e., that does not meet acceptance criteria for any
QC test in this method) must be documented and reported (e.g., as a
qualifier on results), unless the failure is not required to be reported
as determined by the regulatory/control authority. Results associated
with a QC failure cannot be used to demonstrate regulatory compliance.
QC failures do not relieve a discharger or permittee of reporting
[[Page 288]]
timely results. If the holding time would be exceeded for a re-analysis
of the sample, the regulatory/control authority should be consulted for
disposition.
16. Method Performance
16.1 The basic version of this method was tested by 15 laboratories
using reagent water, drinking water, surface water, and industrial
wastewaters spiked at six concentrations over the range 5-1300 [micro]g/
L (Reference 2). Single operator precision, overall precision, and
method accuracy were found to be directly related to the concentration
of the analyte and essentially independent of the sample matrix. Linear
equations to describe these relationships are presented in Table 7.
16.2 As noted in section 1.1, this method was validated through an
interlaboratory study in the early 1980s. However, the fundamental
chemistry principles used in this method remain sound and continue to
apply.
16.3 A chromatogram of the combined acid/base/neutral calibration
standard is shown in Figure 2.
17. Pollution Prevention
17.1 Pollution prevention encompasses any technique that reduces or
eliminates the quantity or toxicity of waste at the point of generation.
Many opportunities for pollution prevention exist in laboratory
operations. EPA has established a preferred hierarchy of environmental
management techniques that places pollution prevention as the management
option of first choice. Whenever feasible, the laboratory should use
pollution prevention techniques to address waste generation. When wastes
cannot be reduced at the source, the Agency recommends recycling as the
next best option.
17.2 The analytes in this method are used in extremely small amounts
and pose little threat to the environment when managed properly.
Standards should be prepared in volumes consistent with laboratory use
to minimize the disposal of excess volumes of expired standards. This
method utilizes significant quantities of methylene chloride.
Laboratories are encouraged to recover and recycle this and other
solvents during extract concentration.
17.3 For information about pollution prevention that may be applied
to laboratories and research institutions, consult Less is Better:
Laboratory Chemical Management for Waste Reduction, available from the
American Chemical Society's Department of Governmental Relations and
Science Policy, 1155 16th Street NW., Washington DC 20036, 202-872-4477.
18. Waste Management
18.1 The laboratory is responsible for complying with all Federal,
State, and local regulations governing waste management, particularly
the hazardous waste identification rules and land disposal restrictions,
and to protect the air, water, and land by minimizing and controlling
all releases from fume hoods and bench operations. Compliance is also
required with any sewage discharge permits and regulations. An overview
of requirements can be found in Environmental Management Guide for Small
Laboratories (EPA 233-B-98-001).
18.2 Samples at pH <2, or pH 12, are hazardous and must
be handled and disposed of as hazardous waste, or neutralized and
disposed of in accordance with all federal, state, and local
regulations. It is the laboratory's responsibility to comply with all
federal, state, and local regulations governing waste management,
particularly the hazardous waste identification rules and land disposal
restrictions. The laboratory using this method has the responsibility to
protect the air, water, and land by minimizing and controlling all
releases from fume hoods and bench operations. Compliance is also
required with any sewage discharge permits and regulations. For further
information on waste management, see ``The Waste Management Manual for
Laboratory Personnel,'' also available from the American Chemical
Society at the address in section 17.3.
18.3 Many analytes in this method decompose above 500 [ordm]C. Low-
level waste such as absorbent paper, tissues, and plastic gloves may be
burned in an appropriate incinerator. Gross quantities of neat or highly
concentrated solutions of toxic or hazardous chemicals should be
packaged securely and disposed of through commercial or governmental
channels that are capable of handling these types of wastes.
18.4 For further information on waste management, consult The Waste
Management Manual for Laboratory Personnel and Less is Better-Laboratory
Chemical Management for Waste Reduction, available from the American
Chemical Society's Department of Government Relations and Science
Policy, 1155 16th Street NW., Washington, DC 20036, 202-872-4477.
19. References
1. ``Sampling and Analysis Procedures for Screening of Industrial
Effluents for Priority Pollutants,'' U.S. Environmental
Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268, March 1977, Revised April
1977.
2. ``EPA Method Study 30, Method 625, Base/Neutrals, Acids, and
Pesticides,'' EPA 600/4-84-053, National Technical Information
Service, PB84-206572, Springfield, Virginia 22161, June 1984.
3. 40 CFR part 136, appendix B.
[[Page 289]]
4. Olynyk, P., Budde, W.L. and Eichelberger, J.W. ``Method Detection
Limit for Methods 624 and 625,'' Unpublished report, May 14,
1980.
5. Annual Book of ASTM Standards, Volume 11.02, D3694-96, ``Standard
Practices for Preparation of Sample Containers and for
Preservation of Organic Constituents,'' American Society for
Testing and Materials, Philadelphia.
6. Solutions to Analytical Chemistry Problems with Clean Water Act
Methods, EPA 821-R-07-002, March 2007.
7. ``Carcinogens-Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for
Disease Control, National Institute for Occupational Safety
and Health, Publication No. 77-206, August 1977.
8. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR part
1910), Occupational Safety and Health Administration, OSHA
2206 (Revised, January 1976).
9. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 7th
Edition, 2003.
10. Johnson, R.A., and Wichern, D.W., ``Applied Multivariate Statistical
Analysis,'' 3rd edition, Prentice Hall, Englewood Cliffs, NJ,
1992.
11. 40 CFR 136.6(b)(4)(x).
12. 40 CFR 136.6(b)(2)(i).
13. Protocol for EPA Approval of New Methods for Organic and Inorganic
Analytes in Wastewater and Drinking Water (EPA-821-B-98-003)
March 1999.
14. Provost, L.P. and Elder, R.S. ``Interpretation of Percent Recovery
Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in section 8.3.3 is two times the value
1.22 derived in this report.)
15. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard
Practices for Sampling Water,'' American Society for Testing
and Materials, Philadelphia.
16. 40 CFR 136.3(a), Table IB, Chlorine--Total Residual.
17. ``Manual of Analytical Methods for the Analysis of Pesticides in
Human and Environmental Samples,'' EPA-600/8-80-038, U.S.
Environmental Protection Agency, Health Effects Research
Laboratory, Research Triangle Park, North Carolina.
18. Eichelberger, J.W., Harris, L.E., and Budde, W.L. ``Reference
Compound to Calibrate Ion Abundance Measurement in Gas
Chromatography-Mass Spectrometry,'' Analytical Chemistry, 47,
995 (1975).
19. Letter of approval of acceptance criteria for DFTPP for time-of-
flight mass spectrometers from William A. Telliard and Herb
Brass of EPA to Jack Cochran of LECO Corporation, February 9,
2005.
20. Tables
Table 1--Non Pesticide/PCB Base/Neutral Extractables \1\
----------------------------------------------------------------------------------------------------------------
Analyte CAS registry MDL \4\ (ug/L) ML \5\ (ug/L)
----------------------------------------------------------------------------------------------------------------
Acenaphthene.................................................... 83-32-9 1.9 5.7
Acenaphthylene.................................................. 208-96-8 3.5 10.5
Anthracene...................................................... 120-12-7 1.9 5.7
Benzidine \2\................................................... 92-87-5 44 132
Benzo(a)anthracene.............................................. 56-55-3 7.8 23.4
Benzo(a)pyrene.................................................. 50-32-8 2.5 7.5
Benzo(b)fluoranthene............................................ 205-99-2 4.8 14.4
Benzo(k)fluoranthene............................................ 207-08-9 2.5 7.5
Benzo(ghi)perylene.............................................. 191-24-2 4.1 12.3
Benzyl butyl phthalate.......................................... 85-68-7 2.5 7.5
bis(2-Chloroethoxy)methane...................................... 111-91-1 5.3 15.9
bis(2-Ethylhexyl)phthalate...................................... 117-81-7 2.5 7.5
bis(2-Chloroisopropyl) ether (2,2'-Oxybis[1-chloropropane])..... 108-60-1 5.7 17.1
4-Bromophenyl phenyl ether...................................... 101-55-3 1.9 5.7
2-Chloronaphthalene............................................. 91-58-7 1.9 5.7
4-Chlorophenyl phenyl ether..................................... 7005-72-3 4.2 12.6
Chrysene........................................................ 218-01-9 2.5 7.5
Dibenz(a,h)anthracene........................................... 53-70-3 2.5 7.5
Di-n-butylphthalate............................................. 84-74-2 2.5 7.5
3,3'-Dichlorobenzidine.......................................... 91-94-1 16.5 49.5
Diethyl phthalate............................................... 84-66-2 1.9 5.7
Dimethyl phthalate.............................................. 131-11-3 1.6 4.8
2,4-Dinitrotoluene.............................................. 121-14-2 5.7 17.1
2,6-Dinitrotoluene.............................................. 606-20-2 1.9 5.7
Di-n-octylphthalate............................................. 117-84-0 2.5 7.5
Fluoranthene.................................................... 206-44-0 2.2 6.6
Fluorene........................................................ 86-73-7 1.9 5.7
Hexachlorobenzene............................................... 118-74-1 1.9 5.7
Hexachlorobutadiene............................................. 87-68-3 0.9 2.7
Hexachloroethane................................................ 67-72-1 1.6 4.8
Indeno(1,2,3-cd)pyrene.......................................... 193-39-5 3.7 11.1
[[Page 290]]
Isophorone...................................................... 78-59-1 2.2 6.6
Naphthalene..................................................... 91-20-3 1.6 4.8
Nitrobenzene.................................................... 98-95-3 1.9 5.7
N-Nitrosodi-n-propylamine \3\................................... 621-64-7 -- --
Phenanthrene.................................................... 85-01-8 5.4 16.2
Pyrene.......................................................... 129-00-0 1.9 5.7
1,2,4-Trichlorobenzene.......................................... 120-82-1 1.9 5.7
----------------------------------------------------------------------------------------------------------------
\1\ All analytes in this table are Priority Pollutants (40 CFR part 423, appendix A).
\2\ Included for tailing factor testing.
\3\ See section 1.2.
\4\ MDL values from the 1984 promulgated version of Method 625.
\5\ ML = Minimum Level--see Glossary for definition and derivation.
Table 2--Acid Extractables \1\
----------------------------------------------------------------------------------------------------------------
Analyte CAS registry MDL \3\ (ug/L) ML \4\ (ug/L)
----------------------------------------------------------------------------------------------------------------
4-Chloro-3-methylphenol......................................... 59-50-7 3.0 9.0
2-Chlorophenol.................................................. 95-57-8 3.3 9.9
2,4-Dichlorophenol.............................................. 120-83-2 2.7 8.1
2,4-Dimethylphenol.............................................. 105-67-9 2.7 8.1
2,4-Dinitrophenol............................................... 51-28-5 42 126
2-Methyl-4,6-dinitrophenol...................................... 534-52-1 24 72
2-Nitrophenol................................................... 88-75-5 3.6 10.8
4-Nitrophenol................................................... 100-02-7 2.4 7.2
Pentachlorophenol \2\........................................... 87-86-5 3.6 10.8
Phenol.......................................................... 108-95-2 1.5 4.5
2,4,6-Trichlorophenol........................................... 88-06-2 2.7 8.1
----------------------------------------------------------------------------------------------------------------
\1\ All analytes in this table are Priority Pollutants (40 CFR part 423, appendix A).
\2\ See section 1.2; included for tailing factor testing.
\3\ MDL values from the 1984 promulgated version of Method 625.
\4\ ML = Minimum Level--see Glossary for definition and derivation.
Table 3--Additional Extractable Analytes \1\, \2\
----------------------------------------------------------------------------------------------------------------
Analyte CAS registry MDL \7\ (ug/L) ML \8\ (ug/L)
----------------------------------------------------------------------------------------------------------------
Acetophenone.................................................... 98-86-2
2-Acetylaminofluorene........................................... 53-96-3
1-Acetyl-2-thiourea............................................. 591-08-2
Alachlor........................................................ 15972-60-8
Aldrin \3\...................................................... 309-00-2 1.9 5.7
Ametryn......................................................... 834-12-8
2-Aminoanthraquinone............................................ 117-79-3
Aminoazobenzene................................................. 60-09-3
4-Aminobiphenyl................................................. 92-67-1
3-Amino-9-ethylcarbazole........................................ 132-32-1
Anilazine....................................................... 101-05-3
Aniline......................................................... 62-53-3
o-Anisidine..................................................... 90-04-0
Aramite......................................................... 140-57-8
Atraton......................................................... 1610-17-9
Atrazine........................................................ 1912-24-9
Azinphos-methyl................................................. 86-50-0
Barban.......................................................... 101-27-9
Benzanthrone.................................................... 82-05-3
Benzenethiol.................................................... 108-98-5
Benzoic acid.................................................... 65-85-0
2,3-Benzofluorene............................................... 243-17-4
p-Benzoquinone.................................................. 106-51-4
Benzyl alcohol.................................................. 100-51-6
alpha-BHC \3\,\4\............................................... 319-84-6
beta-BHC \3\.................................................... 319-85-7 3.1 9.3
gamma-BHC (Lindane) \3\,\4\..................................... 58-89-8 4.2 12.6
delta-BHC \3\................................................... 319-86-8
Biphenyl........................................................ 92-52-4
Bromacil........................................................ 314-40-9
2-Bromochlorobenzene............................................ 694-80-4
3-Bromochlorobenzene............................................ 108-39-2
[[Page 291]]
Bromoxynil...................................................... 1689-84-5
Butachlor....................................................... 2318-4669
Butylate........................................................ 2008-41-5
n-C10 (n-decane)................................................ 124-18-5
n-C12 (n-undecane).............................................. 112-40-2
n-C14 (n-tetradecane)........................................... 629-59-4
n-C16 (n-hexadecane)............................................ 544-76-3
n-C18 (n-octadecane)............................................ 593-45-3
n-C20 (n-eicosane).............................................. 112-95-8
n-C22 (n-docosane).............................................. 629-97-0
n-C24 (n-tetracosane)........................................... 646-31-1
n-C26 (n-hexacosane)............................................ 630-01-3
n-C28 (n-octacosane)............................................ 630-02-4
n-C30 (n-triacontane)........................................... 638-68-6
Captafol........................................................ 2425-06-1
Captan.......................................................... 133-06-2
Carbaryl........................................................ 63-25-2
Carbazole....................................................... 86-74-8
Carbofuran...................................................... 1563-66-2
Carboxin........................................................ 5234-68-4
Carbophenothion................................................. 786-19-6
Chlordane \3\,\5\............................................... 57-74-9
bis(2-Chloroethyl) ether \3\,\4\................................ 111-44-4 5.7 17.1
Chloroneb....................................................... 2675-77-6
4-Chloroaniline................................................. 106-47-8
Chlorobenzilate................................................. 510-15-6
Chlorfenvinphos................................................. 470-90-6
4-Chloro-2-methylaniline........................................ 95-69-2
3-(Chloromethyl)pyridine hydrochloride.......................... 6959-48-4
4-Chloro-2-nitroaniline......................................... 89-63-4
Chlorpropham.................................................... 101-21-3
Chlorothalonil.................................................. 1897-45-6
1-Chloronaphthalene............................................. 90-13-1
3-Chloronitrobenzene............................................ 121-73-3
4-Chloro-1,2-phenylenediamine................................... 95-83-0
4-Chloro-1,3-phenylenediamine................................... 5131-60-2
2-Chlorobiphenyl................................................ 2051-60-7
Chlorpyrifos.................................................... 2921-88-2
Coumaphos....................................................... 56-72-4
m + p-Cresol.................................................... 65794-96-9
o-Cresol........................................................ 95-48-7
p-Cresidine..................................................... 120-71-8
Crotoxyphos..................................................... 7700-17-6
2-Cyclohexyl-4,6-dinitro-phenol................................. 131-89-5
Cyanazine....................................................... 21725-46-2
Cycloate........................................................ 1134-23-2
p-Cymene........................................................ 99-87-6
Dacthal (DCPA).................................................. 1861-32-1
4,4'-DDD \3\.................................................... 72-54-8 2.8 8.4
4,4'-DDE \3\.................................................... 72-55-9 5.6 16.8
4,4'-DDT \3\.................................................... 50-29-3 4.7 14.1
Demeton-O....................................................... 298-03-3
Demeton-S....................................................... 126-75-0
Diallate (cis or trans)......................................... 2303-16-4
2,4-Diaminotoluene.............................................. 95-80-7
Diazinon........................................................ 333-41-5
Dibenz(a,j)acridine............................................. 224-42-0
Dibenzofuran.................................................... 132-64-9
Dibenzo(a,e)pyrene.............................................. 192-65-4
Dibenzothiophene................................................ 132-65-0
1,2-Dibromo-3-chloropropane..................................... 96-12-8
3,5-Dibromo-4-hydroxybenzonitrile............................... 1689-84-5
2,6-Di-tert-butyl-p-benzoquinone................................ 719-22-2
Dichlone........................................................ 117-80-6
2,3-Dichloroaniline............................................. 608-27-5
2,3-Dichlorobiphenyl............................................ 16605-91-7
2,6-Dichloro-4-nitroaniline..................................... 99-30-9
2,3-Dichloronitrobenzene........................................ 3209-22-1
1,3-Dichloro-2-propanol......................................... 96-23-1
2,6-Dichlorophenol.............................................. 120-83-2
Dichlorvos...................................................... 62-73-7
[[Page 292]]
Dicrotophos..................................................... 141-66-2
Dieldrin \3\.................................................... 60-57-1 2.5 7.5
1,2:3,4-Diepoxybutane........................................... 1464-53-5
Di(2-ethylhexyl) adipate........................................ 103-23-1
Diethylstilbestrol.............................................. 56-53-1
Diethyl sulfate................................................. 64-67-5
Dilantin (5,5-Diphenylhydantoin)................................ 57-41-0
Dimethoate...................................................... 60-51-5
3,3[min]-Dimethoxybenzidine..................................... 119-90-4
Dimethylaminoazobenzene......................................... 60-11-7
7,12-Dimethylbenz(a)anthracene.................................. 57-97-6
3,3[min]-Dimethylbenzidine...................................... 119-93-7
N,N-Dimethylformamide........................................... 68-12-2
3,6-Dimethylphenathrene......................................... 1576-67-6
alpha, alpha-Dimethylphenethylamine............................. 122-09-8
Dimethyl sulfone................................................ 67-71-0
1,2-Dinitrobenzene.............................................. 528-29-0
1,3-Dinitrobenzene.............................................. 99-65-0
1,4-Dinitrobenzene.............................................. 100-25-4
Dinocap......................................................... 39300-45-3
Dinoseb......................................................... 88-85-7
Diphenylamine................................................... 122-39-4
Diphenyl ether.................................................. 101-84-8
1,2-Diphenylhydrazine........................................... 122-66-7
Diphenamid...................................................... 957-51-7
Diphenyldisulfide............................................... 882-33-7
Disulfoton...................................................... 298-04-4
Disulfoton sulfoxide............................................ 2497-07-6
Disulfoton sulfone.............................................. 2497-06-5
Endosulfan I \3\,\4\............................................ 959-98-8
Endosulfan II \3\,\4\........................................... 33213-65-9
Endosulfan sulfate \3\.......................................... 1031-07-8 5.6 16.8
Endrin \3\,\4\.................................................. 72-20-8
Endrin aldehyde \3\,\4\......................................... 7421-93-4
Endrin ketone \3\,\4\........................................... 53494-70-5
EPN............................................................. 2104-64-5
EPTC............................................................ 759-94-4
Ethion.......................................................... 563-12-2
Ethoprop........................................................ 13194-48-4
Ethyl carbamate................................................. 51-79-6
Ethyl methanesulfonate.......................................... 65-50-0
Ethylenethiourea................................................ 96-45-7
Etridiazole..................................................... 2593-15-9
Ethynylestradiol-3-methyl ether................................. 72-33-3
Famphur......................................................... 52-85-7
Fenamiphos...................................................... 22224-92-6
Fenarimol....................................................... 60168-88-9
Fensulfothion................................................... 115-90-2
Fenthion........................................................ 55-38-9
Fluchloralin.................................................... 33245-39-5
Fluridone....................................................... 59756-60-4
Heptachlor \3\.................................................. 76-44-8 1.9 5.7
Heptachlor epoxide \3\.......................................... 1024-57-3 2.2 6.6
2,2[min],3,3[min],4,4[min],6-Heptachlorobiphenyl................ 52663-71-5
2,2[min],4,4[min],5[min],6-Hexachlorobiphenyl................... 60145-22-4
Hexachlorocyclopentadiene \3\,\4\............................... 77-47-4
Hexachlorophene................................................. 70-30-4
Hexachloropropene............................................... 1888-71-7
Hexamethylphosphoramide......................................... 680-31-9
Hexanoic acid................................................... 142-62-1
Hexazinone...................................................... 51235-04-2
Hydroquinone.................................................... 123-31-9
Isodrin......................................................... 465-73-6
2-Isopropylnaphthalene.......................................... 2027-17-0
Isosafrole...................................................... 120-58-1
Kepone.......................................................... 143-50-0
Leptophos....................................................... 21609-90-5
Longifolene..................................................... 475-20-7
Malachite green................................................. 569-64-2
Malathion....................................................... 121-75-5
Maleic anhydride................................................ 108-31-6
[[Page 293]]
Merphos......................................................... 150-50-5
Mestranol....................................................... 72-33-3
Methapyrilene................................................... 91-80-5
Methoxychlor.................................................... 72-43-5
2-Methylbenzothioazole.......................................... 120-75-2
3-Methylcholanthrene............................................ 56-49-5
4,4[min]-Methylenebis(2-chloroaniline).......................... 101-14-4
4,4[min]-Methylenebis(N,N-dimethylaniline)...................... 101-61-1
4,5-Methylenephenanthrene....................................... 203-64-5
1-Methylfluorene................................................ 1730-37-6
Methyl methanesulfonate......................................... 66-27-3
2-Methylnaphthalene............................................. 91-57-6
Methylparaoxon.................................................. 950-35-6
Methyl parathion................................................ 298-00-0
1-Methylphenanthrene............................................ 832-69-9
2-(Methylthio)benzothiazole..................................... 615-22-5
Metolachlor..................................................... 5218-45-2
Metribuzin...................................................... 21087-64-9
Mevinphos....................................................... 7786-34-7
Mexacarbate..................................................... 315-18-4
MGK 264......................................................... 113-48-4
Mirex........................................................... 2385-85-5
Molinate........................................................ 2212-67-1
Monocrotophos................................................... 6923-22-4
Naled........................................................... 300-76-5
Napropamide..................................................... 15299-99-7
1,4-Naphthoquinone.............................................. 130-15-4
1-Naphthylamine................................................. 134-32-7
2-Naphthylamine................................................. 91-59-8
1,5-Naphthalenediamine.......................................... 2243-62-1
Nicotine........................................................ 54-11-5
5-Nitroacenaphthene............................................. 602-87-9
2-Nitroaniline.................................................. 88-74-4
3-Nitroaniline.................................................. 99-09-2
4-Nitroaniline.................................................. 100-01-6
5-Nitro-o-anisidine............................................. 99-59-2
4-Nitrobiphenyl................................................. 92-93-3
Nitrofen........................................................ 1836-75-5
5-Nitro-o-toluidine............................................. 99-55-8
Nitroquinoline-1-oxide.......................................... 56-57-5
N-Nitrosodi-n-butylamine \ 4\................................... 924-16-3
N-Nitrosodiethylamine \4\....................................... 55-18-5
N-Nitrosodimethylamine \3\,\4\.................................. 62-75-9
N-Nitrosodiphenylamine \3\,\4\.................................. 86-30-6
N-Nitrosomethylethylamine \4\................................... 10595-95-6
N-Nitrosomethylphenylamine \4\.................................. 614-00-6
N-Nitrosomorpholine \4\......................................... 59-89-2
N-Nitrosopiperidine \4\......................................... 100-75-5
N-Nitrosopyrrolidine \4\........................................ 930-55-2
trans-Nonachlor................................................. 39765-80-5
Norflurazon..................................................... 27314-13-2
2,2[min],3,3[min],4,5[min],6,6[min]-Octachlorobiphenyl.......... 40186-71-8
Octamethyl pyrophosphoramide.................................... 152-16-9
4,4'-Oxydianiline............................................... 101-80-4
Parathion....................................................... 56-38-2
PCB-1016 \3\,\5\................................................ 12674-11-2
PCB-1221 \3\,\5\................................................ 11104-28-2 30 90
PCB-1232 \3\,\5\................................................ 11141-16-5
PCB-1242 \3\,\5\................................................ 53469-21-9
PCB-1248 \3\,\5\................................................ 12672-29-6
PCB-1254 \3\,\5\................................................ 11097-69-1 36 108
PCB-1260 \3\,\5\................................................ 11098-82-5
PCB-1268 \3\,\5\................................................ 11100-14-4
Pebulate........................................................ 1114-71-2
Pentachlorobenzene.............................................. 608-93-5
Pentachloronitrobenzene......................................... 82-68-8
2,2[min],3,4[min],6-Pentachlorobiphenyl......................... 68194-05-8
Pentachloroethane............................................... 76-01-7
Pentamethylbenzene.............................................. 700-12-9
Perylene........................................................ 198-55-0
Phenacetin...................................................... 62-44-2
[[Page 294]]
cis-Permethrin.................................................. 61949-76-6
trans-Permethrin................................................ 61949-77-7
Phenobarbital................................................... 50-06-6
Phenothiazene................................................... 92-84-2
1,4-Phenylenediamine............................................ 624-18-0
1-Phenylnaphthalene............................................. 605-02-7
2-Phenylnaphthalene............................................. 612-94-2
Phorate......................................................... 298-02-2
Phosalone....................................................... 2310-18-0
Phosmet......................................................... 732-11-6
Phosphamidon.................................................... 13171-21-6
Phthalic anhydride.............................................. 85-44-9
alpha-Picoline (2-Methylpyridine)............................... 109-06-8
Piperonyl sulfoxide............................................. 120-62-7
Prometon........................................................ 1610-18-0
Prometryn....................................................... 7287-19-6
Pronamide....................................................... 23950-58-5
Propachlor...................................................... 1918-16-7
Propazine....................................................... 139-40-2
Propylthiouracil................................................ 51-52-5
Pyridine........................................................ 110-86-1
Resorcinol (1,3-Benzenediol).................................... 108-46-3
Safrole......................................................... 94-59-7
Simazine........................................................ 122-34-9
Simetryn........................................................ 1014-70-6
Squalene........................................................ 7683-64-9
Stirofos........................................................ 22248-79-9
Strychnine...................................................... 57-24-9
Styrene \9\..................................................... 100-42-5
Sulfallate...................................................... 95-06-7
Tebuthiuron..................................................... 34014-18-1
Terbacil........................................................ 5902-51-2
Terbufos........................................................ 13071-79-9
Terbutryn....................................................... 886-50-0
alpha-Terpineol................................................. 98-55-5
1,2,4,5-Tetrachlorobenzene...................................... 95-94-3
2,2[min],4,4[min]-Tetrachlorobiphenyl........................... 2437-79-8
2,3,7,8-Tetrachlorodibenzo-p-dioxin............................. 1746-01-6
2,3,4,6-Tetrachlorophenol....................................... 58-90-2
Tetrachlorvinphos............................................... 22248-79-9
Tetraethyl dithiopyrophosphate.................................. 3689-24-5
Tetraethyl pyrophosphate........................................ 107-49-3
Thianaphthene (2,3-Benzothiophene).............................. 95-15-8
Thioacetamide................................................... 62-55-5
Thionazin....................................................... 297-97-2
Thiophenol (Benzenethiol)....................................... 108-98-5
Thioxanthone.................................................... 492-22-8
Toluene-1,3-diisocyanate........................................ 26471-62-5
Toluene-2,4-diisocyanate........................................ 584-84-9
o-Toluidine..................................................... 95-53-4
Toxaphene \3\,\5\............................................... 8001-35-2
Triadimefon..................................................... 43121-43-3
1,2,3-Trichlorobenzene.......................................... 87-61-6
2,4,5-Trichlorobiphenyl......................................... 15862-07-4
2,3,6-Trichlorophenol........................................... 933-75-5
2,4,5-Trichlorophenol........................................... 95-95-4
Tricyclazole.................................................... 41814-78-2
Trifluralin..................................................... 1582-09-8
1,2,3-Trimethoxybenzene......................................... 634-36-6
2,4,5-Trimethylaniline.......................................... 137-17-7
Trimethyl phosphate............................................. 512-56-1
Triphenylene.................................................... 217-59-4
Tripropyleneglycolmethyl ether.................................. 20324-33-8
1,3,5-Trinitrobenzene........................................... 99-35-4
Tris(2,3-dibromopropyl) phosphate............................... 126-72-7
Tri-p-tolyl phosphate........................................... 78-32-0
O,O,O-Triethyl phosphorothioate................................. 126-68-1
Trithiane....................................................... 291-29-4
Vernolate....................................................... 1929-77-7 ..............
----------------------------------------------------------------------------------------------------------------
\1\ Compounds that have been demonstrated amenable to extraction and gas chromatography.
\2\ Determine each analyte in the fraction that gives the most accurate result.
[[Page 295]]
\3\ Priority Pollutant (40 CFR part 423, appendix A).
\4\ See section 1.2.
\5\ These compounds are mixtures of various isomers.
\6\ Detected as azobenzene.
\7\ MDL values from the 1984 promulgated version of Method 625.
\8\ ML = Minimum Level--see Glossary for definition and derivation.
\9\ Styrene may be susceptible to losses during sampling, preservation, and/or extraction of full-volume (1 L)
water samples. However, styrene is not regulated at 40 CFR part 136, and it is also listed as an analyte in
EPA Method 624.1 and EPA Method 1625C, where such losses may be less than using Method 625.1.
Table 4--Chromatographic Conditions and Characteristic m/z's for Base/Neutral Extractables
--------------------------------------------------------------------------------------------------------------------------------------------------------
Characteristic m/z's
Retention -----------------------------------------------------------------------------
Analyte time (sec) Electron impact ionization Chemical ionization
\1\ -----------------------------------------------------------------------------
Primary Second Second Methane Methane Methane
--------------------------------------------------------------------------------------------------------------------------------------------------------
N-Nitrosodimethylamine....................................... 385 42 74 44 ...........
bis(2-Chloroethyl) ether..................................... 704 93 63 95 63 107 109
bis(2-Chloroisopropyl) ether................................. 799 45 77 79 77 135 137
Hexachloroethane............................................. 823 117 201 199 199 201 203
N-Nitrosodi-n-propylamine.................................... 830 130 42 101 ...........
Nitrobenzene................................................. 849 77 123 65 124 152 164
Isophorone................................................... 889 82 95 138 139 167 178
bis(2-Chloroethoxy) methane.................................. 939 93 95 123 65 107 137
1,2,4-Trichlorobenzene....................................... 958 180 182 145 181 183 209
Naphthalene.................................................. 967 128 129 127 129 157 169
Hexachlorobutadiene.......................................... 1006 225 223 227 223 225 227
Hexachlorocyclopentadiene.................................... 1142 237 235 272 235 237 239
2-Chloronaphthalene.......................................... 1200 162 164 127 163 191 203
Acenaphthylene............................................... 1247 152 151 153 152 153 181
Dimethyl phthalate........................................... 1273 163 194 164 151 163 164
2,6-Dinitrotoluene........................................... 1300 165 89 121 183 211 223
Acenaphthene................................................. 1304 154 153 152 154 155 183
2,4-Dinitrotoluene........................................... 1364 165 63 182 183 211 223
Fluorene..................................................... 1401 166 165 167 166 167 195
4-Chlorophenyl phenyl ether.................................. 1409 204 206 141 ...........
Diethyl phthalate............................................ 1414 149 177 150 177 223 251
N-Nitrosodiphenylamine....................................... 1464 169 168 167 169 170 198
4-Bromophenyl phenyl ether................................... 1498 248 250 141 249 251 277
alpha-BHC.................................................... 1514 183 181 109 ...........
Hexachlorobenzene............................................ 1522 284 142 249 284 286 288
beta-BHC..................................................... 1544 183 181 109 ...........
gamma-BHC.................................................... 1557 181 183 109 ...........
Phenanthrene................................................. 1583 178 179 176 178 179 207
Anthracene................................................... 1592 178 179 176 178 179 207
delta-BHC.................................................... 1599 183 109 181 ...........
Heptachlor................................................... 1683 100 272 274 ...........
Di-n-butyl phthalate......................................... 1723 149 150 104 149 205 279
Aldrin....................................................... 1753 66 263 220 ...........
Fluoranthene................................................. 1817 202 101 100 203 231 243
Heptachlor epoxide........................................... 1820 353 355 351 ...........
gamma-Chlordane.............................................. 1834 373 375 377 ...........
Pyrene....................................................... 1852 202 101 100 203 231 243
Benzidine\ 2\................................................ 1853 184 92 185 185 213 225
alpha-Chlordane.............................................. 1854 373 375 377 ...........
Endosulfan I................................................. 1855 237 339 341 ...........
4,4[min]-DDE................................................. 1892 246 248 176 ...........
Dieldrin..................................................... 1907 79 263 279 ...........
Endrin....................................................... 1935 81 263 82 ...........
Endosulfan II................................................ 2014 237 339 341 ...........
4,4[min]-DDD................................................. 2019 235 237 165 ...........
Endrin aldehyde.............................................. 2031 67 345 250 ...........
Butyl benzyl phthalate....................................... 2060 149 91 206 149 299 327
Endosulfan sulfate........................................... 2068 272 387 422 ...........
4,4[min]-DDT................................................. 2073 235 237 165 ...........
Chrysene..................................................... 2083 228 226 229 228 229 257
3,3[min]-Dichlorobenzidine................................... 2086 252 254 126 ...........
Benzo(a)anthracene........................................... 2090 228 229 226 228 229 257
[[Page 296]]
bis(2-Ethylhexyl) phthalate.................................. 2124 149 167 279 149
Di-n-octyl phthalate......................................... 2240 149 43 57 ...........
Benzo(b)fluoranthene......................................... 2286 252 253 125 252 253 281
Benzo(k)fluoranthene......................................... 2293 252 253 125 252 253 281
Benzo(a)pyrene............................................... 2350 252 253 125 252 253 281
Indeno(1,2,3-cd) pyrene...................................... 2650 276 138 277 276 277 305
Dibenz(a,h)anthracene........................................ 2660 278 139 279 278 279 307
Benzo(ghi)perylene........................................... 2750 276 138 277 276 277 305
Toxaphene.................................................... ........... 159 231 233 ...........
PCB 1016..................................................... ........... 224 260 294 ...........
PCB 1221..................................................... ........... 190 224 260 ...........
PCB 1232..................................................... ........... 190 224 260 ...........
PCB 1242..................................................... ........... 224 260 294 ...........
PCB 1248..................................................... ........... 294 330 262 ...........
PCB 1254..................................................... ........... 294 330 362 ...........
PCB 1260..................................................... ........... 330 362 394 ........... ...........
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Column: 30 m x 0.25 mm ID; 94% methyl, 5% phenyl, 1% vinyl bonded phase fused silica capillary.
Conditions: 5 min at 30 [deg]C; 30-280 at 8 [deg]C per min; isothermal at 280 [deg]C until benzo(ghi)perylene elutes.
Gas velocity: 30 cm/sec at 30 [deg]C (at constant pressure).
\2\ See section 1.2; included for tailing factor testing.
Table 5--Chromatographic Conditions and Characteristic m/z's for Acid Extractables
--------------------------------------------------------------------------------------------------------------------------------------------------------
Characteristic m/z's
Retention -----------------------------------------------------------------------------
Analyte Time (sec) Electron impact ionization Chemical ionization
\1\ -----------------------------------------------------------------------------
Prime Second Second Methane Methane Methane
--------------------------------------------------------------------------------------------------------------------------------------------------------
2-Chlorophenol............................................... 705 128 64 130 129 131 157
Phenol....................................................... 700 94 65 66 95 123 135
2-Nitrophenol................................................ 900 139 65 109 140 168 122
2,4-Dimethylphenol........................................... 924 122 107 121 123 151 163
2,4-Dichlorophenol........................................... 947 162 164 98 163 165 167
4-Chloro-3-methylphenol...................................... 1091 142 107 144 143 171 183
2,4,6-Trichlorophenol........................................ 1165 196 198 200 197 199 201
2,4-Dinitrophenol............................................ 1325 184 63 154 185 213 225
4-Nitrophenol................................................ 1354 65 139 109 140 168 122
2-Methyl-4,6-dinitrophenol................................... 1435 198 182 77 199 227 239
Pentachlorophenol............................................ 1561 266 264 268 267 265 269
--------------------------------------------------------------------------------------------------------------------------------------------------------
Column: 30 m x 0.25 mm ID; 94% methyl, 5% phenyl, 1% vinyl bonded phase fused silica capillary.
Conditions: 5 min at 30 [deg]C; 30-250 at 8 [deg]C per min; isothermal at 280 [deg]C until pentachlorophenol elutes.
Gas velocity: 30 cm/sec at 30 [deg]C (at constant pressure).
Table 6--QC Acceptance Criteria--Method 625 \1\
----------------------------------------------------------------------------------------------------------------
Range for Q Limit for s Range for X Range for P1, Limit for RPD
Analyte (%) \2\ (%) \3\ (%) \3\ P2(%) \3\ (%)
----------------------------------------------------------------------------------------------------------------
Acenaphthene.................... 70-130 29 60-132 47-145 48
Acenaphthylene.................. 60-130 45 54-126 33-145 74
Aldrin.......................... 7-152 39 7-152 D-166 81
Anthracene...................... 58-130 40 43-120 27-133 66
Benzo(a)anthracene.............. 42-133 32 42-133 33-143 53
Benzo(b)fluoranthene............ 42-140 43 42-140 24-159 71
Benzo(k)fluoranthene............ 25-146 38 25-146 11-162 63
Benzo(a)pyrene.................. 32-148 43 32-148 17-163 72
Benzo(ghi)perylene.............. 13-195 61 D-195 D-219 97
Benzyl butyl phthalate.......... 43-140 36 D-140 D-152 60
beta-BHC........................ 42-131 37 42-131 24-149 61
delta-BHC....................... D-130 77 D-120 D-120 129
bis(2-Chloroethyl)ether......... 52-130 65 43-126 12-158 108
bis(2-Chloroethoxy)methane...... 52-164 32 49-165 33-184 54
bis(2-Chloroisopropyl) ether.... 63-139 46 63-139 36-166 76
bis(2-Ethylhexyl) phthalate..... 43-137 50 29-137 8-158 82
[[Page 297]]
4-Bromophenyl phenyl ether...... 70-130 26 65-120 53-127 43
2-Chloronaphthalene............. 70-130 15 65-120 60-120 24
4-Chlorophenyl phenyl ether..... 57-145 36 38-145 25-158 61
Chrysene........................ 44-140 53 44-140 17-168 87
4,4[min]-DDD.................... D-135 56 D-135 D-145 93
4,4[min]-DDE.................... 19-130 46 19-120 4-136 77
4,4[min]-DDT.................... D-171 81 D-171 D-203 135
Dibenz(a,h)anthracene........... 13-200 75 D-200 D-227 126
Di-n-butyl phthalate............ 52-130 28 8-120 1-120 47
3,3[min]-Dichlorobenzidine...... 18-213 65 8-213 D-262 108
Dieldrin........................ 70-130 38 44-119 29-136 62
Diethyl phthalate............... 47-130 60 D-120 D-120 100
Dimethyl phthalate.............. 50-130 110 D-120 D-120 183
2,4-Dinitrotoluene.............. 53-130 25 48-127 39-139 42
2,6-Dinitrotoluene.............. 68-137 29 68-137 50-158 48
Di-n-octyl phthalate............ 21-132 42 19-132 4-146 69
Endosulfan sulfate.............. D-130 42 D-120 D-120 70
Endrin aldehyde................. D-189 45 D-189 D-209 75
Fluoranthene.................... 47-130 40 43-121 26-137 66
Fluorene........................ 70-130 23 70-120 59-121 38
Heptachlor...................... D-172 44 D-172 D-192 74
Heptachlor epoxide.............. 70-130 61 71-120 26-155 101
Hexachlorobenzene............... 38-142 33 8-142 D-152 55
Hexachlorobutadiene............. 68-130 38 38-120 24-120 62
Hexachloroethane................ 55-130 32 55-120 40-120 52
Indeno(1,2,3-cd)pyrene.......... 13-151 60 D-151 D-171 99
Isophorone...................... 52-180 56 47-180 21-196 93
Naphthalene..................... 70-130 39 36-120 21-133 65
Nitrobenzene.................... 54-158 37 54-158 35-180 62
N-Nitrosodi-n-propylamine....... 59-170 52 14-198 D-230 87
PCB-1260........................ 19-130 77 19-130 D-164 128
Phenanthrene.................... 67-130 24 65-120 54-120 39
Pyrene.......................... 70-130 30 70-120 52-120 49
1,2,4-Trichlorobenzene.......... 61-130 30 57-130 44-142 50
4-Chloro-3-methylphenol......... 68-130 44 41-128 22-147 73
2-Chlorophenol.................. 55-130 37 36-120 23-134 61
2,4-Dichlorophenol.............. 64-130 30 53-122 39-135 50
2,4-Dimethylphenol.............. 58-130 35 42-120 32-120 58
2,4-Dinitrophenol............... 39-173 79 D-173 D-191 132
2-Methyl-4,6-dinitrophenol...... 56-130 122 53-130 D-181 203
2-Nitrophenol................... 61-163 33 45-167 29-182 55
4-Nitrophenol................... 35-130 79 13-129 D-132 131
Pentachlorophenol............... 42-152 52 38-152 14-176 86
Phenol.......................... 48-130 39 17-120 5-120 64
2,4,6-Trichlorophenol........... 69-130 35 52-129 37-144 58
----------------------------------------------------------------------------------------------------------------
\1\ Acceptance criteria are based upon method performance data in Table 7 and from EPA Method 1625. Where
necessary, limits for recovery have been broadened to assure applicability to concentrations below those used
to develop Table 7.
\2\ Test concentration = 100 [micro]g/mL.
\3\ Test concentration = 100 [micro]g/L.
Q = Calibration verification (sections 7.3.1 and 13.4).
s = Standard deviation for four recovery measurements in the DOC test (section 8.2.4).
X = Average recovery for four recovery measurements in the DOC test (section 8.2.4).
P1, P2 = MS/MSD recovery (section 8.3.2, section 8.4.2).
RPD = MS/MSD relative percent difference (RPD; section 8.3.3).
D = Detected; result must be greater than zero.
Table 7--Precision and Recovery as Functions of Concentration--Method 625 \1\
----------------------------------------------------------------------------------------------------------------
Single analyst Overall
Recovery, precision, precision,
Analyte X[min] sr[min] S[min]
([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
Acenaphthene................................................. 0.96C + 0.19 0.15 X-0.12 0.21 X-0.67
Acenaphthylene............................................... 0.89C + 0.74 0.24 X-1.06 0.26 X-0.54
Aldrin....................................................... 0.78C + 1.66 0.27 X-1.28 0.43 X + 1.13
Anthracene................................................... 0.80C + 0.68 0.21 X-0.32 0.27 X-0.64
Benzo(a)anthracene........................................... 0.88C-0.60 0.15 X + 0.93 0.26 X-0.28
Benzo(b)fluoranthene......................................... 0.93C-1.80 0.22 X + 0.43 0.29 X + 0.96
Benzo(k)fluoranthene......................................... 0.87C-1.56 0.19 X + 1.03 0.35 X + 0.40
Benzo(a)pyrene............................................... 0.90C-0.13 0.22 X + 0.48 0.32 X + 1.35
Benzo(ghi)perylene........................................... 0.98C-0.86 0.29 X + 2.40 0.51 X-0.44
Benzyl butyl phthalate....................................... 0.66C-1.68 0.18 X + 0.94 0.53 X + 0.92
[[Page 298]]
beta-BHC..................................................... 0.87C-0.94 0.20 X-0.58 0.30 X-1.94
delta-BHC.................................................... 0.29C-1.09 0.34 X + 0.86 0.93 X-0.17
bis(2-Chloroethyl) ether..................................... 0.86C-1.54 0.35 X-0.99 0.35 X + 0.10
bis(2-Chloroethoxy) methane.................................. 1.12C-5.04 0.16 X + 1.34 0.26 X + 2.01
bis(2-Chloroisopropyl) ether................................. 1.03C-2.31 0.24 X + 0.28 0.25 X + 1.04
bis(2-Ethylhexyl) phthalate.................................. 0.84C-1.18 0.26 X + 0.73 0.36 X + 0.67
4-Bromophenyl phenyl ether................................... 0.91C-1.34 0.13 X + 0.66 0.16 X + 0.66
2-Chloronaphthalene.......................................... 0.89C + 0.01 0.07 X + 0.52 0.13 X + 0.34
4-Chlorophenyl phenyl ether.................................. 0.91C + 0.53 0.20 X-0.94 0.30 X-0.46
Chrysene..................................................... 0.93C-1.00 0.28 X + 0.13 0.33 X-0.09
4,4[min]-DDD................................................. 0.56C-0.40 0.29 X-0.32 0.66 X-0.96
4,4[min]-DDE................................................. 0.70C-0.54 0.26 X-1.17 0.39 X-1.04
4,4[min]-DDT................................................. 0.79C-3.28 0.42 X + 0.19 0.65 X-0.58
Dibenz(a,h)anthracene........................................ 0.88C + 4.72 0.30 X + 8.51 0.59 X + 0.25
Di-n-butyl phthalate......................................... 0.59C + 0.71 0.13 X + 1.16 0.39 X + 0.60
3,3'-Dichlorobenzidine....................................... 1.23C-12.65 0.28 X + 7.33 0.47 X + 3.45
Dieldrin..................................................... 0.82C-0.16 0.20 X-0.16 0.26 X-0.07
Diethyl phthalate............................................ 0.43C + 1.00 0.28 X + 1.44 0.52 X + 0.22
Dimethyl phthalate........................................... 0.20C + 1.03 0.54 X + 0.19 1.05 X-0.92
2,4-Dinitrotoluene........................................... 0.92C-4.81 0.12 X + 1.06 0.21 X + 1.50
2,6-Dinitrotoluene........................................... 1.06C-3.60 0.14 X + 1.26 0.19 X + 0.35
Di-n-octyl phthalate......................................... 0.76C-0.79 0.21 X + 1.19 0.37 X + 1.19
Endosulfan sulfate........................................... 0.39C + 0.41 0.12 X + 2.47 0.63 X-1.03
Endrin aldehyde.............................................. 0.76C-3.86 0.18 X + 3.91 0.73 X-0.62
Fluoranthene................................................. 0.81C + 1.10 0.22 X + 0.73 0.28 X-0.60
Fluorene..................................................... 0.90C-0.00 0.12 X + 0.26 0.13 X + 0.61
Heptachlor................................................... 0.87C-2.97 0.24 X-0.56 0.50 X-0.23
Heptachlor epoxide........................................... 0.92C-1.87 0.33 X-0.46 0.28 X + 0.64
Hexachlorobenzene............................................ 0.74C + 0.66 0.18 X-0.10 0.43 X-0.52
Hexachlorobutadiene.......................................... 0.71C-1.01 0.19 X + 0.92 0.26 X + 0.49
Hexachloroethane............................................. 0.73C-0.83 0.17 X + 0.67 0.17 X + 0.80
Indeno(1,2,3-cd)pyrene....................................... 0.78C-3.10 0.29 X + 1.46 0.50 X + 0.44
Isophorone................................................... 1.12C + 1.41 0.27 X + 0.77 0.33 X + 0.26
Naphthalene.................................................. 0.76C + 1.58 0.21 X-0.41 0.30 X-0.68
Nitrobenzene................................................. 1.09C-3.05 0.19 X + 0.92 0.27 X + 0.21
N-Nitrosodi-n-propylamine.................................... 1.12C-6.22 0.27 X + 0.68 0.44 X + 0.47
PCB-1260..................................................... 0.81C-10.86 0.35 X + 3.61 0.43 X + 1.82
Phenanthrene................................................. 0.87C-0.06 0.12 X + 0.57 0.15 X + 0.25
Pyrene....................................................... 0.84C-0.16 0.16 X + 0.06 0.15 X + 0.31
1,2,4-Trichlorobenzene....................................... 0.94C-0.79 0.15 X + 0.85 0.21 X + 0.39
4-Chloro-3-methylphenol...................................... 0.84C + 0.35 0.23 X + 0.75 0.29 X + 1.31
2-Chlorophenol............................................... 0.78C + 0.29 0.18 X + 1.46 0.28 X + 0.97
2,4-Dichlorophenol........................................... 0.87C + 0.13 0.15 X + 1.25 0.21 X + 1.28
2,4-Dimethylphenol........................................... 0.71C + 4.41 0.16 X + 1.21 0.22 X + 1.31
2,4-Dinitrophenol............................................ 0.81C-18.04 0.38 X + 2.36 0.42 X + 26.29
2-Methyl-4,6-Dinitrophenol................................... 1.04C-28.04 0.05 X + 42.29 0.26 X + 23.10
2-Nitrophenol................................................ 1.07C-1.15 0.16 X + 1.94 0.27 X + 2.60
4-Nitrophenol................................................ 0.61C-1.22 0.38 X + 2.57 0.44 X + 3.24
Pentachlorophenol............................................ 0.93C + 1.99 0.24 X + 3.03 0.30 X + 4.33
Phenol....................................................... 0.43C + 1.26 0.26 X + 0.73 0.35 X + 0.58
2,4,6-Trichlorophenol........................................ 0.91C-0.18 0.16 X + 2.22 0.22 X + 1.81
----------------------------------------------------------------------------------------------------------------
\1\ Regressions based on data from Reference 2.
X[min] = Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/
L.
sr[min] = Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S[min] = Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C = True value for the concentration, in [micro]g/L.
X = Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
Table 8--Suggested Internal and Surrogate Standards
------------------------------------------------------------------------
Range for surrogate recovery
(%) \1\
Base/neutral fraction -------------------------------
Calibration Recovery from
verification samples
------------------------------------------------------------------------
Acenaphthalene-d8....................... 66-152 33-168
Acenaphthene-d10........................ 71-141 30-180
Aniline-d5..............................
Anthracene-d10.......................... 58-171 23-142
[[Page 299]]
Benzo(a)anthracene-d12.................. 28-357 22-329
Benzo(a)pyrene-d12...................... 32-194 32-194
4-Chloroaniline-d4...................... 1-145 1-145
bis(2-Chloroethyl) ether-d8............. 52-194 25-222
Chrysene-d12............................ 23-290 23-290
Decafluorobiphenyl......................
4,4[min]-Dibromobiphenyl................
4,4[min]-Dibromooctafluorobiphenyl......
1,4-Dichlorobenzene-d4.................. 65-153 11-245
2,2[min]-Difluorobiphenyl...............
Dimethyl phthalate-d6................... 47-211 1-500
Fluoranthene-d10........................ 47-215 30-187
Fluorene-d10............................ 61-164 38-172
4-Fluoroaniline.........................
1-Fluoronaphthalene.....................
2-Fluoronaphthalene.....................
2-Methylnaphthalene-d10................. 50-150 50-150
Naphthalene-d8.......................... 71-141 22-192
Nitrobenzene-d5......................... 46-219 15-314
2,3,4,5,6-Pentafluorobiphenyl...........
Perylene-d12............................
Phenanthrene-d10........................ 67-149 34-168
Pyrene-d10.............................. 48-210 28-196
Pyridine-d5.............................
Acid fraction...........................
2-Chlorophenol-d4....................... 55-180 33-180
2,4-Dichlorophenol-d3................... 64-157 34-182
4,6-Dinitro-2-methylphenol-d2........... 56-177 22-307
2-Fluorophenol..........................
4-Methylphenol-d8....................... 25-111 25-111
2-Nitrophenol-d4........................ 61-163 37-163
4-Nitrophenol-d4........................ 35-287 6-500
Pentafluorophenol.......................
2-Perfluoromethylphenol.................
Phenol-d5............................... 48-208 8-424
------------------------------------------------------------------------
\1\ Recovery from samples is the wider of the criteria in the CLP SOW
for organics or in Method 1625.
Table 9A--DFTPP Key m/z's and Abundance Criteria for Quadrupole
Instruments \1\
------------------------------------------------------------------------
m/z Abundance criteria
------------------------------------------------------------------------
51.......................... 30-60 percent of m/z 198.
68.......................... Less than 2 percent of m/z 69.
70.......................... Less than 2 percent of m/z 69.
127......................... 40-60 percent of base peak m/z 198.
197......................... Less than 1 percent of m/z 198.
198......................... Base peak, 100 percent relative abundance.
199......................... 5-9 percent of m/z 198.
275......................... 10-30 percent of m/z 198.
365......................... Greater than 1 percent of m/z 198.
441......................... Present but less than m/z 443.
442......................... 40-100 percent of m/z 198.
443......................... 17-23 percent of m/z 442.
------------------------------------------------------------------------
\1\ Criteria in these tables are for quadrupole and time-of-flight
instruments. Alternative tuning criteria from other published EPA
reference methods may be used provided method performance is not
adversely affected. Alternative tuning criteria specified by an
instrument manufacturer may also be used for another type of mass
spectrometer, provided method performance is not adversely affected.
Table 9B--DFTPP Key m/z's and Abundance Criteria for Time-of-flight
Instruments \1\
------------------------------------------------------------------------
m/z Abundance criteria
------------------------------------------------------------------------
51.......................... 10-85 percent of the base peak.
68.......................... Less than 2 percent of m/z 69.
70.......................... Less than 2 percent of m/z 69.
127......................... 10-80 percent of the base peak.
197......................... Less than 2 percent of Mass 198.
[[Page 300]]
198......................... Base peak, or greater than 50% of m/z 442.
199......................... 5-9 percent of m/z 198.
275......................... 10-60 percent of the base peak.
365......................... Greater than 0.5 percent of m/z 198.
441......................... Less than 150 percent of m/z 443.
442......................... Base peak or greater than 30 percent of m/
z 198.
443......................... 15-24 percent of m/z 442.
------------------------------------------------------------------------
\1\ Criteria in these tables are for quadrupole and time-of-flight
instruments. Alternative tuning criteria from other published EPA
reference methods may be used provided method performance is not
adversely affected. Alternative tuning criteria specified by an
instrument manufacturer may also be used for another type of mass
spectrometer, or for an alternative carrier gas, provided method
performance is not adversely affected.
21. Figures
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[GRAPHIC] [TIFF OMITTED] TR28AU17.018
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[GRAPHIC] [TIFF OMITTED] TR28AU17.019
22. Glossary
These definitions and purposes are specific to this method but have
been conformed to common usage to the extent possible.
22.1 Units of weight and measure and their abbreviations.
22.1.1 Symbols.
[deg]C degrees Celsius
[micro]g microgram
[micro]L microliter
< less than
greater than
<= less than or equal to
% percent
22.1.2 Abbreviations (in alphabetical order).
cm centimeter
g gram
h hour
ID inside diameter
in. inch
L liter
m mass or meter
mg milligram
min minute
mL milliliter
mm millimeter
ms millisecond
m/z mass-to-charge ratio
N normal; gram molecular weight of solute divided by hydrogen equivalent
of solute, per liter of solution
ng nanogram
pg picogram
ppb part-per-billion
ppm part-per-million
ppt part-per-trillion
psig pounds-per-square inch gauge
22.2 Definitions and acronyms (in alphabetical order).
Analyte--A compound or mixture of compounds (e.g., PCBs) tested for
by this method. The analytes are listed in Tables 1-3.
Batch--See Extraction.
Blank--An aliquot of reagent water that is treated exactly as a
sample including exposure to all glassware, equipment, solvents,
reagents, internal standards, and surrogates that are used with samples.
The blank is used to determine if analytes or interferences are present
in the laboratory environment, the reagents, or the apparatus.
Calibration--The process of determining the relationship between the
output or response of a measuring instrument and the value of an input
standard. Historically, EPA has referred to a multi-point calibration as
the ``initial calibration,'' to differentiate it from a single-point
calibration verification.
Calibration standard--A solution prepared from stock solutions and/
or a secondary standards and containing the analytes of interest,
surrogates, and internal standards. The calibration standard is used to
calibrate the response of the GC/MS instrument against analyte
concentration.
[[Page 303]]
Calibration verification standard--The mid-point calibration
standard used to verify calibration. See sections 7.3 and 13.4.
Descriptor--In SIM, the beginning and ending retention times for the
RT window, the m/z's sampled in the RT window, and the dwell time at
each m/z.
Extracted ion current profile (EICP)--The line described by the
signal at a given m/z.
Extraction Batch--A set of up to 20 field samples (not including QC
samples) started through the extraction process on a given 24-hour shift
(section 3.1). Each extraction batch must be accompanied by a blank
(section 8.5), a laboratory control sample (LCS, section 8.4), and a
matrix spike and duplicate (MS/MSD; Section 8.3), resulting in a minimum
of five analyses (1 sample, 1 blank, 1 LCS, 1 MS, and 1 MSD) and a
maximum of 24 analyses (20 field samples, 1 blank, 1 LCS, 1 MS, and 1
MSD) for the batch. If greater than 20 samples are to be extracted in a
24-hour shift, the samples must be separated into extraction batches of
20 or fewer samples.
Field Duplicates--Two samples collected at the same time and placed
under identical conditions, and treated identically throughout field and
laboratory procedures. Results of analyses of the field duplicates
provide an estimate of the precision associated with sample collection,
preservation, and storage, as well as with laboratory procedures.
Field blank--An aliquot of reagent water or other reference matrix
that is placed in a sample container in the field, and treated as a
sample in all respects, including exposure to sampling site conditions,
storage, preservation, and all analytical procedures. The purpose of the
field blank is to determine if the field or sample transporting
procedures and environments have contaminated the sample.
GC--Gas chromatograph or gas chromatography.
Internal standard--A compound added to an extract or standard
solution in a known amount and used as a reference for quantitation of
the analytes of interest and surrogates. In this method the internal
standards are stable isotopically labeled analogs of selected method
analytes (Table 8). Also see Internal standard quantitation.
Internal standard quantitation--A means of determining the
concentration of an analyte of interest (Tables 1-3) by reference to a
compound not expected to be found in a sample.
DOC--Initial demonstration of capability (section 8.2); four
aliquots of reagent water spiked with the analytes of interest and
analyzed to establish the ability of the laboratory to generate
acceptable precision and recovery. A DOC is performed prior to the first
time this method is used and any time the method or instrumentation is
modified.
Laboratory Control Sample (LCS; laboratory fortified blank; section
8.4)--An aliquot of reagent water spiked with known quantities of the
analytes of interest and surrogates. The LCS is analyzed exactly like a
sample. Its purpose is to assure that the results produced by the
laboratory remain within the limits specified in this method for
precision and recovery.
Laboratory fortified sample matrix--See Matrix spike.
Laboratory reagent blank--A blank run on laboratory reagents; e.g.,
methylene chloride (section 11.1.5).
Matrix spike (MS) and matrix spike duplicate (MSD) (laboratory
fortified sample matrix and duplicate)--Two aliquots of an environmental
sample to which known quantities of the analytes of interest and
surrogates are added in the laboratory. The MS/MSD are prepared and
analyzed exactly like a field sample. Their purpose is to quantify any
additional bias and imprecision caused by the sample matrix. The
background concentrations of the analytes in the sample matrix must be
determined in a separate aliquot and the measured values in the MS/MSD
corrected for background concentrations.
May--This action, activity, or procedural step is neither required
nor prohibited.
May not--This action, activity, or procedural step is prohibited.
Method blank--See blank.
Method detection limit (MDL)--A detection limit determined by the
procedure at 40 CFR part 136, appendix B. The MDLs determined by EPA in
the original version of the method are listed in Tables 1, 2 and 3. As
noted in section 1.5, use the MDLs in Tables 1, 2, and 3 in conjunction
with current MDL data from the laboratory actually analyzing samples to
assess the sensitivity of this procedure relative to project objectives
and regulatory requirements (where applicable).
Minimum level (ML)--The term ``minimum level'' refers to either the
sample concentration equivalent to the lowest calibration point in a
method or a multiple of the method detection limit (MDL), whichever is
higher. Minimum levels may be obtained in several ways: They may be
published in a method; they may be based on the lowest acceptable
calibration point used by a laboratory; or they may be calculated by
multiplying the MDL in a method, or the MDL determined by a laboratory,
by a factor of 3. For the purposes of NPDES compliance monitoring, EPA
considers the following terms to be synonymous: ``quantitation limit,''
``reporting limit,'' and ``minimum level.''
MS--Mass spectrometer or mass spectrometry, or matrix spike (a QC
sample type).
MSD--Matrix spike duplicate (a QC sample type).
Must--This action, activity, or procedural step is required.
[[Page 304]]
m/z--The ratio of the mass of an ion (m) detected in the mass
spectrometer to the charge (z) of that ion.
Preparation blank--See blank.
Quality control check sample (QCS)--See Laboratory Control Sample.
Reagent water--Water demonstrated to be free from the analytes of
interest and potentially interfering substances at the MDLs for the
analytes in this method.
Regulatory compliance limit (or regulatory concentration limit)--A
limit on the concentration or amount of a pollutant or contaminant
specified in a nationwide standard, in a permit, or otherwise
established by a regulatory/control authority.
Relative retention time (RRT)--The ratio of the retention time of an
analyte to the retention time of its associated internal standard. RRT
compensates for small changes in the GC temperature program that can
affect the absolute retention times of the analyte and internal
standard. RRT is a unitless quantity.
Relative standard deviation (RSD)--The standard deviation times 100
divided by the mean. Also termed ``coefficient of variation.''
RF--Response factor. See section 7.2.2.
RSD--See relative standard deviation.
Safety Data Sheet (SDS)--Written information on a chemical's
toxicity, health hazards, physical properties, fire, and reactivity,
including storage, spill, and handling precautions that meet the
requirements of OSHA, 29 CFR 1910.1200(g) and appendix D to Sec.
1910.1200. United Nations Globally Harmonized System of Classification
and Labelling of Chemicals (GHS), third revised edition, United Nations,
2009.
Selected Ion Monitoring (SIM)--An MS technique in which a few m/z's
are monitored. When used with gas chromatography, the m/z's monitored
are usually changed periodically throughout the chromatographic run, to
correlate with the characteristic m/z's of the analytes, surrogates, and
internal standards as they elute from the chromatographic column. The
technique is often used to increase sensitivity and minimize
interferences.
Signal-to-noise ratio (S/N)--The height of the signal as measured
from the mean (average) of the noise to the peak maximum divided by the
width of the noise.
Should--This action, activity, or procedural step is suggested but
not required.
SPE--Solid-phase extraction; an extraction technique in which an
analyte is extracted from an aqueous solution by passage over or through
a material capable of reversibly adsorbing the analyte. Also termed
liquid-solid extraction.
Stock solution--A solution containing an analyte that is prepared
using a reference material traceable to EPA, the National Institute of
Science and Technology (NIST), or a source that will attest to the
purity, authenticity, and concentration of the standard.
Surrogate--A compound unlikely to be found in a sample, and which is
spiked into sample in a known amount before extraction or other
processing, and is quantitated with the same procedures used to quantify
other sample components. The purpose of the surrogate is to monitor
method performance with each sample.
Method 1613, Revision B
Tetra- Through Octa-Chlorinated Dioxins and Furans by Isotope Dilution
HRGC/HRMS
1.0 Scope and Application
1.1 This method is for determination of tetra- through octa-
chlorinated dibenzo-p-dioxins (CDDs) and dibenzofurans (CDFs) in water,
soil, sediment, sludge, tissue, and other sample matrices by high
resolution gas chromatography/high resolution mass spectrometry (HRGC/
HRMS). The method is for use in EPA's data gathering and monitoring
programs associated with the Clean Water Act, the Resource Conservation
and Recovery Act, the Comprehensive Environmental Response, Compensation
and Liability Act, and the Safe Drinking Water Act. The method is based
on a compilation of EPA, industry, commercial laboratory, and academic
methods (References 1-6).
1.2 The seventeen 2,3,7,8-substituted CDDs/CDFs listed in Table 1
may be determined by this method. Specifications are also provided for
separate determination of 2,3,7,8-tetrachloro-dibenzo-p-dioxin (2,3,7,8-
TCDD) and 2,3,7,8-tetrachloro-dibenzofuran (2,3,7,8-TCDF).
1.3 The detection limits and quantitation levels in this method are
usually dependent on the level of interferences rather than instrumental
limitations. The minimum levels (MLs) in Table 2 are the levels at which
the CDDs/CDFs can be determined with no interferences present. The
Method Detection Limit (MDL) for 2,3,7,8-TCDD has been determined as 4.4
pg/L (parts-per-quadrillion) using this method.
1.4 The GC/MS portions of this method are for use only by analysts
experienced with HRGC/HRMS or under the close supervision of such
qualified persons. Each laboratory that uses this method must
demonstrate the ability to generate acceptable results using the
procedure in Section 9.2.
1.5 This method is ``performance-based''. The analyst is permitted
to modify the method to overcome interferences or lower the cost of
measurements, provided that all performance criteria in this method are
met. The requirements for establishing method equivalency are given in
Section 9.1.2.
[[Page 305]]
1.6 Any modification of this method, beyond those expressly
permitted, shall be considered a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
2.0 Summary of Method
Flow charts that summarize procedures for sample preparation,
extraction, and analysis are given in Figure 1 for aqueous and solid
samples, Figure 2 for multi-phase samples, and Figure 3 for tissue
samples.
2.1 Extraction.
2.1.1 Aqueous samples (samples containing less than 1% solids)--
Stable isotopically labeled analogs of 15 of the 2,3,7,8-substituted
CDDs/CDFs are spiked into a 1 L sample, and the sample is extracted by
one of three procedures:
2.1.1.1 Samples containing no visible particles are extracted with
methylene chloride in a separatory funnel or by the solid-phase
extraction technique summarized in Section 2.1.1.3. The extract is
concentrated for cleanup.
2.1.1.2 Samples containing visible particles are vacuum filtered
through a glass-fiber filter. The filter is extracted in a Soxhlet/Dean-
Stark (SDS) extractor (Reference 7), and the filtrate is extracted with
methylene chloride in a separatory funnel. The methylene chloride
extract is concentrated and combined with the SDS extract prior to
cleanup.
2.1.1.3 The sample is vacuum filtered through a glass-fiber filter
on top of a solid-phase extraction (SPE) disk. The filter and disk are
extracted in an SDS extractor, and the extract is concentrated for
cleanup.
2.1.2 Solid, semi-solid, and multi-phase samples (but not tissue)--
The labeled compounds are spiked into a sample containing 10 g (dry
weight) of solids. Samples containing multiple phases are pressure
filtered and any aqueous liquid is discarded. Coarse solids are ground
or homogenized. Any non-aqueous liquid from multi-phase samples is
combined with the solids and extracted in an SDS extractor. The extract
is concentrated for cleanup.
2.1.3 Fish and other tissue--The sample is extracted by one of two
procedures:
2.1.3.1 Soxhlet or SDS extraction--A 20 g aliquot of sample is
homogenized, and a 10 g aliquot is spiked with the labeled compounds.
The sample is mixed with sodium sulfate, allowed to dry for 12-24 hours,
and extracted for 18-24 hours using methylene chloride:hexane (1:1) in a
Soxhlet extractor. The extract is evaporated to dryness, and the lipid
content is determined.
2.1.3.2 HCl digestion--A 20 g aliquot is homogenized, and a 10 g
aliquot is placed in a bottle and spiked with the labeled compounds.
After equilibration, 200 mL of hydrochloric acid and 200 mL of methylene
chloride:hexane (1:1) are added, and the bottle is agitated for 12-24
hours. The extract is evaporated to dryness, and the lipid content is
determined.
2.2 After extraction, \37\Cl4-labeled 2,3,7,8-TCDD is
added to each extract to measure the efficiency of the cleanup process.
Sample cleanups may include back-extraction with acid and/or base, and
gel permeation, alumina, silica gel, Florisil and activated carbon
chromatography. High-performance liquid chromatography (HPLC) can be
used for further isolation of the 2,3,7,8-isomers or other specific
isomers or congeners. Prior to the cleanup procedures cited above,
tissue extracts are cleaned up using an anthropogenic isolation column,
a batch silica gel adsorption, or sulfuric acid and base back-
extraction, depending on the tissue extraction procedure used.
2.3 After cleanup, the extract is concentrated to near dryness.
Immediately prior to injection, internal standards are added to each
extract, and an aliquot of the extract is injected into the gas
chromatograph. The analytes are separated by the GC and detected by a
high-resolution (=10,000) mass spectrometer. Two exact m/z's
are monitored for each analyte.
2.4 An individual CDD/CDF is identified by comparing the GC
retention time and ion-abundance ratio of two exact m/z's with the
corresponding retention time of an authentic standard and the
theoretical or acquired ion-abundance ratio of the two exact m/z's. The
non-2,3,7,8 substituted isomers and congeners are identified when
retention times and ion-abundance ratios agree within predefined limits.
Isomer specificity for 2,3,7,8-TCDD and 2,3,7,8-TCDF is achieved using
GC columns that resolve these isomers from the other tetra-isomers.
2.5 Quantitative analysis is performed using selected ion current
profile (SICP) areas, in one of three ways:
2.5.1 For the 15 2,3,7,8-substituted CDDs/CDFs with labeled analogs
(see Table 1), the GC/MS system is calibrated, and the concentration of
each compound is determined using the isotope dilution technique.
2.5.2 For 1,2,3,7,8,9-HxCDD, OCDF, and the labeled compounds, the
GC/MS system is calibrated and the concentration of each compound is
determined using the internal standard technique.
2.5.3 For non-2,3,7,8-substituted isomers and for all isomers at a
given level of chlorination (i.e., total TCDD), concentrations are
determined using response factors from calibration of the CDDs/CDFs at
the same level of chlorination.
2.6 The quality of the analysis is assured through reproducible
calibration and testing of the extraction, cleanup, and GC/MS systems.
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3.0 Definitions
Definitions are given in the glossary at the end of this method.
4.0 Contamination and Interferences
4.1 Solvents, reagents, glassware, and other sample processing
hardware may yield artifacts and/or elevated baselines causing
misinterpretation of chromatograms (References 8-9). Specific selection
of reagents and purification of solvents by distillation in all-glass
systems may be required. Where possible, reagents are cleaned by
extraction or solvent rinse.
4.2 Proper cleaning of glassware is extremely important, because
glassware may not only contaminate the samples but may also remove the
analytes of interest by adsorption on the glass surface.
4.2.1 Glassware should be rinsed with solvent and washed with a
detergent solution as soon after use as is practical. Sonication of
glassware containing a detergent solution for approximately 30 seconds
may aid in cleaning. Glassware with removable parts, particularly
separatory funnels with fluoropolymer stopcocks, must be disassembled
prior to detergent washing.
4.2.2 After detergent washing, glassware should be rinsed
immediately, first with methanol, then with hot tap water. The tap water
rinse is followed by another methanol rinse, then acetone, and then
methylene chloride.
4.2.3 Do not bake reusable glassware in an oven as a routine part of
cleaning. Baking may be warranted after particularly dirty samples are
encountered but should be minimized, as repeated baking of glassware may
cause active sites on the glass surface that will irreversibly adsorb
CDDs/CDFs.
4.2.4 Immediately prior to use, the Soxhlet apparatus should be pre-
extracted with toluene for approximately three hours (see Sections
12.3.1 through 12.3.3). Separatory funnels should be shaken with
methylene chloride/toluene (80/20 mixture) for two minutes, drained, and
then shaken with pure methylene chloride for two minutes.
4.3 All materials used in the analysis shall be demonstrated to be
free from interferences by running reference matrix method blanks
initially and with each sample batch (samples started through the
extraction process on a given 12-hour shift, to a maximum of 20
samples).
4.3.1 The reference matrix must simulate, as closely as possible,
the sample matrix under test. Ideally, the reference matrix should not
contain the CDDs/CDFs in detectable amounts, but should contain
potential interferents in the concentrations expected to be found in the
samples to be analyzed. For example, a reference sample of human adipose
tissue containing pentachloronaphthalene can be used to exercise the
cleanup systems when samples containing pentachloronaphthalene are
expected.
4.3.2 When a reference matrix that simulates the sample matrix under
test is not available, reagent water (Section 7.6.1) can be used to
simulate water samples; playground sand (Section 7.6.2) or white quartz
sand (Section 7.3.2) can be used to simulate soils; filter paper
(Section 7.6.3) can be used to simulate papers and similar materials;
and corn oil (Section 7.6.4) can be used to simulate tissues.
4.4 Interferences coextracted from samples will vary considerably
from source to source, depending on the diversity of the site being
sampled. Interfering compounds may be present at concentrations several
orders of magnitude higher than the CDDs/CDFs. The most frequently
encountered interferences are chlorinated biphenyls, methoxy biphenyls,
hydroxydiphenyl ethers, benzylphenyl ethers, polynuclear aromatics, and
pesticides. Because very low levels of CDDs/CDFs are measured by this
method, the elimination of interferences is essential. The cleanup steps
given in Section 13 can be used to reduce or eliminate these
interferences and thereby permit reliable determination of the CDDs/CDFs
at the levels shown in Table 2.
4.5 Each piece of reusable glassware should be numbered to associate
that glassware with the processing of a particular sample. This will
assist the laboratory in tracking possible sources of contamination for
individual samples, identifying glassware associated with highly
contaminated samples that may require extra cleaning, and determining
when glassware should be discarded.
4.6 Cleanup of tissue--The natural lipid content of tissue can
interfere in the analysis of tissue samples for the CDDs/CDFs. The lipid
contents of different species and portions of tissue can vary widely.
Lipids are soluble to varying degrees in various organic solvents and
may be present in sufficient quantity to overwhelm the column
chromatographic cleanup procedures used for cleanup of sample extracts.
Lipids must be removed by the lipid removal procedures in Section 13.7,
followed by alumina (Section 13.4) or Florisil (Section 13.8), and
carbon (Section 13.5) as minimum additional cleanup steps. If
chlorodiphenyl ethers are detected, as indicated by the presence of
peaks at the exact m/z's monitored for these interferents, alumina and/
or Florisil cleanup must be employed to eliminate these interferences.
5.0 Safety
5.1 The toxicity or carcinogenicity of each compound or reagent used
in this method has not been precisely determined; however, each chemical
compound should be
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treated as a potential health hazard. Exposure to these compounds should
be reduced to the lowest possible level.
5.1.1 The 2,3,7,8-TCDD isomer has been found to be acnegenic,
carcinogenic, and teratogenic in laboratory animal studies. It is
soluble in water to approximately 200 ppt and in organic solvents to
0.14%. On the basis of the available toxicological and physical
properties of 2,3,7,8-TCDD, all of the CDDs/CDFs should be handled only
by highly trained personnel thoroughly familiar with handling and
cautionary procedures and the associated risks.
5.1.2 It is recommended that the laboratory purchase dilute standard
solutions of the analytes in this method. However, if primary solutions
are prepared, they shall be prepared in a hood, and a NIOSH/MESA
approved toxic gas respirator shall be worn when high concentrations are
handled.
5.2 The laboratory is responsible for maintaining a current
awareness file of OSHA regulations regarding the safe handling of the
chemicals specified in this method. A reference file of material safety
data sheets (MSDSs) should also be made available to all personnel
involved in these analyses. It is also suggested that the laboratory
perform personal hygiene monitoring of each analyst who uses this method
and that the results of this monitoring be made available to the
analyst. Additional information on laboratory safety can be found in
References 10-13. The references and bibliography at the end of
Reference 13 are particularly comprehensive in dealing with the general
subject of laboratory safety.
5.3 The CDDs/CDFs and samples suspected to contain these compounds
are handled using essentially the same techniques employed in handling
radioactive or infectious materials. Well-ventilated, controlled access
laboratories are required. Assistance in evaluating the health hazards
of particular laboratory conditions may be obtained from certain
consulting laboratories and from State Departments of Health or Labor,
many of which have an industrial health service. The CDDs/CDFs are
extremely toxic to laboratory animals. Each laboratory must develop a
strict safety program for handling these compounds. The practices in
References 2 and 14 are highly recommended.
5.3.1 Facility--When finely divided samples (dusts, soils, dry
chemicals) are handled, all operations (including removal of samples
from sample containers, weighing, transferring, and mixing) should be
performed in a glove box demonstrated to be leak tight or in a fume hood
demonstrated to have adequate air flow. Gross losses to the laboratory
ventilation system must not be allowed. Handling of the dilute solutions
normally used in analytical and animal work presents no inhalation
hazards except in the case of an accident.
5.3.2 Protective equipment--Disposable plastic gloves, apron or lab
coat, safety glasses or mask, and a glove box or fume hood adequate for
radioactive work should be used. During analytical operations that may
give rise to aerosols or dusts, personnel should wear respirators
equipped with activated carbon filters. Eye protection equipment
(preferably full face shields) must be worn while working with exposed
samples or pure analytical standards. Latex gloves are commonly used to
reduce exposure of the hands. When handling samples suspected or known
to contain high concentrations of the CDDs/CDFs, an additional set of
gloves can also be worn beneath the latex gloves.
5.3.3 Training--Workers must be trained in the proper method of
removing contaminated gloves and clothing without contacting the
exterior surfaces.
5.3.4 Personal hygiene--Hands and forearms should be washed
thoroughly after each manipulation and before breaks (coffee, lunch, and
shift).
5.3.5 Confinement--Isolated work areas posted with signs, segregated
glassware and tools, and plastic absorbent paper on bench tops will aid
in confining contamination.
5.3.6 Effluent vapors--The effluents of sample splitters from the
gas chromatograph (GC) and from roughing pumps on the mass spectrometer
(MS) should pass through either a column of activated charcoal or be
bubbled through a trap containing oil or high-boiling alcohols to
condense CDD/CDF vapors.
5.3.7 Waste Handling--Good technique includes minimizing
contaminated waste. Plastic bag liners should be used in waste cans.
Janitors and other personnel must be trained in the safe handling of
waste.
5.3.8 Decontamination
5.3.8.1 Decontamination of personnel--Use any mild soap with plenty
of scrubbing action.
5.3.8.2 Glassware, tools, and surfaces--Chlorothene NU Solvent is
the least toxic solvent shown to be effective. Satisfactory cleaning may
be accomplished by rinsing with Chlorothene, then washing with any
detergent and water. If glassware is first rinsed with solvent, then the
dish water may be disposed of in the sewer. Given the cost of disposal,
it is prudent to minimize solvent wastes.
5.3.9 Laundry--Clothing known to be contaminated should be collected
in plastic bags. Persons who convey the bags and launder the clothing
should be advised of the hazard and trained in proper handling. The
clothing may be put into a washer without contact if the launderer knows
of the potential problem. The washer should be run through a cycle
before being used again for other clothing.
5.3.10 Wipe tests--A useful method of determining cleanliness of
work surfaces and
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tools is to wipe the surface with a piece of filter paper. Extraction
and analysis by GC with an electron capture detector (ECD) can achieve a
limit of detection of 0.1 [micro]g per wipe; analysis using this method
can achieve an even lower detection limit. Less than 0.1 [micro]g per
wipe indicates acceptable cleanliness; anything higher warrants further
cleaning. More than 10 [micro]g on a wipe constitutes an acute hazard
and requires prompt cleaning before further use of the equipment or work
space, and indicates that unacceptable work practices have been
employed.
5.3.11 Table or wrist-action shaker--The use of a table or wrist-
action shaker for extraction of tissues presents the possibility of
breakage of the extraction bottle and spillage of acid and flammable
organic solvent. A secondary containment system around the shaker is
suggested to prevent the spread of acid and solvents in the event of
such a breakage. The speed and intensity of shaking action should also
be adjusted to minimize the possibility of breakage.
6.0 Apparatus and Materials
Note: Brand names, suppliers, and part numbers are for illustration
purposes only and no endorsement is implied. Equivalent performance may
be achieved using apparatus and materials other than those specified
here. Meeting the performance requirements of this method is the
responsibility of the laboratory.
6.1 Sampling Equipment for Discrete or Composite Sampling
6.1.1 Sample bottles and caps
6.1.1.1 Liquid samples (waters, sludges and similar materials
containing 5% solids or less)--Sample bottle, amber glass, 1.1 L
minimum, with screw cap.
6.1.1.2 Solid samples (soils, sediments, sludges, paper pulps,
filter cake, compost, and similar materials that contain more than 5%
solids)--Sample bottle, wide mouth, amber glass, 500 mL minimum.
6.1.1.3 If amber bottles are not available, samples shall be
protected from light.
6.1.1.4 Bottle caps--Threaded to fit sample bottles. Caps shall be
lined with fluoropolymer.
6.1.1.5 Cleaning
6.1.1.5.1 Bottles are detergent water washed, then solvent rinsed
before use.
6.1.1.5.2 Liners are detergent water washed, rinsed with reagent
water (Section 7.6.1) followed by solvent, and baked at approximately
200 [deg]C for a minimum of 1 hour prior to use.
6.1.2 Compositing equipment--Automatic or manual compositing system
incorporating glass containers cleaned per bottle cleaning procedure
above. Only glass or fluoropolymer tubing shall be used. If the sampler
uses a peristaltic pump, a minimum length of compressible silicone
rubber tubing may be used in the pump only. Before use, the tubing shall
be thoroughly rinsed with methanol, followed by repeated rinsing with
reagent water to minimize sample contamination. An integrating flow
meter is used to collect proportional composite samples.
6.2 Equipment for Glassware Cleaning--Laboratory sink with overhead
fume hood.
6.3 Equipment for Sample Preparation
6.3.1 Laboratory fume hood of sufficient size to contain the sample
preparation equipment listed below.
6.3.2 Glove box (optional).
6.3.3 Tissue homogenizer--VirTis Model 45 Macro homogenizer
(American Scientific Products H-3515, or equivalent) with stainless
steel Macro-shaft and Turbo-shear blade.
6.3.4 Meat grinder--Hobart, or equivalent, with 3-5 mm holes in
inner plate.
6.3.5 Equipment for determining percent moisture
6.3.5.1 Oven--Capable of maintaining a temperature of 110 5 [deg]C.
6.3.5.2 Dessicator.
6.3.6 Balances
6.3.6.1 Analytical--Capable of weighing 0.1 mg.
6.3.6.2 Top loading--Capable of weighing 10 mg.
6.4 Extraction Apparatus
6.4.1 Water samples
6.4.1.1 pH meter, with combination glass electrode.
6.4.1.2 pH paper, wide range (Hydrion Papers, or equivalent).
6.4.1.3 Graduated cylinder, 1 L capacity.
6.4.1.4 Liquid/liquid extraction--Separatory funnels, 250 mL, 500
mL, and 2000 mL, with fluoropolymer stopcocks.
6.4.1.5 Solid-phase extraction
6.4.1.5.1 One liter filtration apparatus, including glass funnel,
glass frit support, clamp, adapter, stopper, filtration flask, and
vacuum tubing (Figure 4). For wastewater samples, the apparatus should
accept 90 or 144 mm disks. For drinking water or other samples
containing low solids, smaller disks may be used.
6.4.1.5.2 Vacuum source capable of maintaining 25 in. Hg, equipped
with shutoff valve and vacuum gauge.
6.4.1.5.3 Glass-fiber filter--Whatman GMF 150 (or equivalent), 1
micron pore size, to fit filtration apparatus in Section 6.4.1.5.1.
6.4.1.5.4 Solid-phase extraction disk containing octadecyl
(C18) bonded silica uniformly enmeshed in an inert matrix--
Fisher Scientific 14-378F (or equivalent), to fit filtration apparatus
in Section 6.4.1.5.1.
6.4.2 Soxhlet/Dean-Stark (SDS) extractor (Figure 5)--For filters and
solid/sludge samples.
6.4.2.1 Soxhlet--50 mm ID, 200 mL capacity with 500 mL flask (Cal-
Glass LG-6900, or equivalent, except substitute 500 mL round-bottom
flask for 300 mL flat-bottom flask).
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6.4.2.2 Thimble--43 x 123 to fit Soxhlet (Cal-Glass LG-6901-122, or
equivalent).
6.4.2.3 Moisture trap--Dean Stark or Barret with fluoropolymer
stopcock, to fit Soxhlet.
6.4.2.4 Heating mantle--Hemispherical, to fit 500 mL round-bottom
flask (Cal-Glass LG-8801-112, or equivalent).
6.4.2.5 Variable transformer--Powerstat (or equivalent), 110 volt,
10 amp.
6.4.3 Apparatus for extraction of tissue.
6.4.3.1 Bottle for extraction (if digestion/extraction using HCl is
used)'' 500-600 mL wide-mouth clear glass, with fluoropolymer-lined cap.
6.4.3.2 Bottle for back-extraction--100-200 mL narrow-mouth clear
glass with fluoropolymer-lined cap.
6.4.3.3 Mechanical shaker--Wrist-action or platform-type rotary
shaker that produces vigorous agitation (Sybron Thermolyne Model LE
``Big Bill'' rotator/shaker, or equivalent).
6.4.3.4 Rack attached to shaker table to permit agitation of four to
nine samples simultaneously.
6.4.4 Beakers--400-500 mL.
6.4.5 Spatulas--Stainless steel.
6.5 Filtration Apparatus.
6.5.1 Pyrex glass wool--Solvent-extracted by SDS for three hours
minimum.
Note: Baking glass wool may cause active sites that will
irreversibly adsorb CDDs/CDFs.
6.5.2 Glass funnel--125-250 mL.
6.5.3 Glass-fiber filter paper--Whatman GF/D (or equivalent), to fit
glass funnel in Section 6.5.2.
6.5.4 Drying column--15-20 mm ID Pyrex chromatographic column
equipped with coarse-glass frit or glass-wool plug.
6.5.5 Buchner funnel--15 cm.
6.5.6 Glass-fiber filter paper--to fit Buchner funnel in Section
6.5.5.
6.5.7 Filtration flasks--1.5-2.0 L, with side arm.
6.5.8 Pressure filtration apparatus--Millipore YT30 142 HW, or
equivalent.
6.6 Centrifuge Apparatus.
6.6.1 Centrifuge--Capable of rotating 500 mL centrifuge bottles or
15 mL centrifuge tubes at 5,000 rpm minimum.
6.6.2 Centrifuge bottles--500 mL, with screw-caps, to fit
centrifuge.
6.6.3 Centrifuge tubes--12-15 mL, with screw-caps, to fit
centrifuge.
6.7 Cleanup Apparatus.
6.7.1 Automated gel permeation chromatograph (Analytical Biochemical
Labs, Inc, Columbia, MO, Model GPC Autoprep 1002, or equivalent).
6.7.1.1 Column--600-700 mm long x 25 mm ID, packed with 70 g of
SX-3 Bio-beads (Bio-Rad Laboratories, Richmond, CA, or equivalent).
6.7.1.2 Syringe--10 mL, with Luer fitting.
6.7.1.3 Syringe filter holder--stainless steel, and glass-fiber or
fluoropolymer filters (Gelman 4310, or equivalent).
6.7.1.4 UV detectors--254 nm, preparative or semi-preparative flow
cell (Isco, Inc., Type 6; Schmadzu, 5 mm path length; Beckman-Altex
152W, 8 [micro]L micro-prep flow cell, 2 mm path; Pharmacia UV-1, 3 mm
flow cell; LDC Milton-Roy UV-3, monitor 1203; or equivalent).
6.7.2 Reverse-phase high-performance liquid chromatograph.
6.7.2.1 Column oven and detector--Perkin-Elmer Model LC-65T (or
equivalent) operated at 0.02 AUFS at 235 nm.
6.7.2.2 Injector--Rheodyne 7120 (or equivalent) with 50 [micro]L
sample loop.
6.7.2.3 Column--Two 6.2 mm x 250 mm Zorbax-ODS columns in series
(DuPont Instruments Division, Wilmington, DE, or equivalent), operated
at 50 [deg]C with 2.0 mL/min methanol isocratic effluent.
6.7.2.4 Pump--Altex 110A (or equivalent).
6.7.3 Pipets.
6.7.3.1 Disposable, pasteur--150 mm long x 5-mm ID (Fisher
Scientific 13-678-6A, or equivalent).
6.7.3.2 Disposable, serological--10 mL (6 mm ID).
6.7.4 Glass chromatographic columns.
6.7.4.1 150 mm long x 8-mm ID, (Kontes K-420155, or equivalent) with
coarse-glass frit or glass-wool plug and 250 mL reservoir.
6.7.4.2 200 mm long x 15 mm ID, with coarse-glass frit or glass-wool
plug and 250 mL reservoir.
6.7.4.3 300 mm long x 25 mm ID, with 300 mL reservoir and glass or
fluoropolymer stopcock.
6.7.5 Stirring apparatus for batch silica cleanup of tissue
extracts.
6.7.5.1 Mechanical stirrer--Corning Model 320, or equivalent.
6.7.5.2 Bottle--500-600 mL wide-mouth clear glass.
6.7.6 Oven--For baking and storage of adsorbents, capable of
maintaining a constant temperature (5 [deg]C) in
the range of 105-250 [deg]C.
6.8 Concentration Apparatus.
6.8.1 Rotary evaporator--Buchi/Brinkman-American Scientific No.
E5045-10 or equivalent, equipped with a variable temperature water bath.
6.8.1.1 Vacuum source for rotary evaporator equipped with shutoff
valve at the evaporator and vacuum gauge.
6.8.1.2 A recirculating water pump and chiller are recommended, as
use of tap water for cooling the evaporator wastes large volumes of
water and can lead to inconsistent performance as water temperatures and
pressures vary.
6.8.1.3 Round-bottom flask--100 mL and 500 mL or larger, with
ground-glass fitting compatible with the rotary evaporator.
6.8.2 Kuderna-Danish (K-D) Concentrator.
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6.8.2.1 Concentrator tube--10 mL, graduated (Kontes K-570050-1025,
or equivalent) with calibration verified. Ground-glass stopper (size 19/
22 joint) is used to prevent evaporation of extracts.
6.8.2.2 Evaporation flask--500 mL (Kontes K-570001-0500, or
equivalent), attached to concentrator tube with springs (Kontes K-
662750-0012 or equivalent).
6.8.2.3 Snyder column--Three-ball macro (Kontes K-503000-0232, or
equivalent).
6.8.2.4 Boiling chips.
6.8.2.4.1 Glass or silicon carbide--Approximately 10/40 mesh,
extracted with methylene chloride and baked at 450 [deg]C for one hour
minimum.
6.8.2.4.2 Fluoropolymer (optional)--Extracted with methylene
chloride.
6.8.2.5 Water bath--Heated, with concentric ring cover, capable of
maintaining a temperature within 2 [deg]C,
installed in a fume hood.
6.8.3 Nitrogen blowdown apparatus--Equipped with water bath
controlled in the range of 30-60 [deg]C (N-Evap, Organomation
Associates, Inc., South Berlin, MA, or equivalent), installed in a fume
hood.
6.8.4 Sample vials.
6.8.4.1 Amber glass--2-5 mL with fluoropolymer-lined screw-cap.
6.8.4.2 Glass--0.3 mL, conical, with fluoropolymer-lined screw or
crimp cap.
6.9 Gas Chromatograph--Shall have splitless or on-column injection
port for capillary column, temperature program with isothermal hold, and
shall meet all of the performance specifications in Section 10.
6.9.1 GC column for CDDs/CDFs and for isomer specificity for
2,3,7,8-TCDD--60 5 m long x 0.32 0.02 mm ID; 0.25 [micro]m 5% phenyl, 94% methyl, 1%
vinyl silicone bonded-phase fused-silica capillary column (J&W DB-5, or
equivalent).
6.9.2 GC column for isomer specificity for 2,3,7,8-TCDF--30 5 m long x 0.32 0.02 mm ID; 0.25
[micro]m bonded-phase fused-silica capillary column (J&W DB-225, or
equivalent).
6.10 Mass Spectrometer--28-40 eV electron impact ionization, shall
be capable of repetitively selectively monitoring 12 exact m/z's minimum
at high resolution (=10,000) during a period of approximately
one second, and shall meet all of the performance specifications in
Section 10.
6.11 GC/MS Interface--The mass spectrometer (MS) shall be interfaced
to the GC such that the end of the capillary column terminates within 1
cm of the ion source but does not intercept the electron or ion beams.
6.12 Data System--Capable of collecting, recording, and storing MS
data.
7.0 Reagents and Standards
7.1 pH Adjustment and Back-Extraction.
7.1.1 Potassium hydroxide--Dissolve 20 g reagent grade KOH in 100 mL
reagent water.
7.1.2 Sulfuric acid--Reagent grade (specific gravity 1.84).
7.1.3 Hydrochloric acid--Reagent grade, 6N.
7.1.4 Sodium chloride--Reagent grade, prepare at 5% (w/v) solution
in reagent water.
7.2 Solution Drying and Evaporation.
7.2.1 Solution drying--Sodium sulfate, reagent grade, granular,
anhydrous (Baker 3375, or equivalent), rinsed with methylene chloride
(20 mL/g), baked at 400 [deg]C for one hour minimum, cooled in a
dessicator, and stored in a pre-cleaned glass bottle with screw-cap that
prevents moisture from entering. If, after heating, the sodium sulfate
develops a noticeable grayish cast (due to the presence of carbon in the
crystal matrix), that batch of reagent is not suitable for use and
should be discarded. Extraction with methylene chloride (as opposed to
simple rinsing) and baking at a lower temperature may produce sodium
sulfate that is suitable for use.
7.2.2 Tissue drying--Sodium sulfate, reagent grade, powdered,
treated and stored as above.
7.2.3 Prepurified nitrogen.
7.3 Extraction.
7.3.1 Solvents--Acetone, toluene, cyclohexane, hexane, methanol,
methylene chloride, and nonane; distilled in glass, pesticide quality,
lot-certified to be free of interferences.
7.3.2 White quartz sand, 60/70 mesh--For Soxhlet/Dean-Stark
extraction (Aldrich Chemical, Cat. No. 27-437-9, or equivalent). Bake at
450 [deg]C for four hours minimum.
7.4 GPC Calibration Solution--Prepare a solution containing 300 mg/
mL corn oil, 15 mg/mL bis(2-ethylhexyl) phthalate, 1.4 mg/mL
pentachlorophenol, 0.1 mg/mL perylene, and 0.5 mg/mL sulfur.
7.5 Adsorbents for Sample Cleanup.
7.5.1 Silica gel.
7.5.1.1 Activated silica gel--100-200 mesh, Supelco 1-3651 (or
equivalent), rinsed with methylene chloride, baked at 180 [deg]C for a
minimum of one hour, cooled in a dessicator, and stored in a precleaned
glass bottle with screw-cap that prevents moisture from entering.
7.5.1.2 Acid silica gel (30% w/w)--Thoroughly mix 44.0 g of
concentrated sulfuric acid with 100.0 g of activated silica gel in a
clean container. Break up aggregates with a stirring rod until a uniform
mixture is obtained. Store in a bottle with a fluoropolymer-lined screw-
cap.
7.5.1.3 Basic silica gel--Thoroughly mix 30 g of 1N sodium hydroxide
with 100 g of activated silica gel in a clean container. Break up
aggregates with a stirring rod until a uniform mixture is obtained.
Store in a bottle with a fluoropolymer-lined screw-cap.
7.5.1.4 Potassium silicate.
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7.5.1.4.1 Dissolve 56 g of high purity potassium hydroxide (Aldrich,
or equivalent) in 300 mL of methanol in a 750-1000 mL flat-bottom flask.
7.5.1.4.2 Add 100 g of silica gel and a stirring bar, and stir on a
hot plate at 60-70 [deg]C for one to two hours.
7.5.1.4.3 Decant the liquid and rinse the potassium silicate twice
with 100 mL portions of methanol, followed by a single rinse with 100 mL
of methylene chloride.
7.5.1.4.4 Spread the potassium silicate on solvent-rinsed aluminum
foil and dry for two to four hours in a hood.
7.5.1.4.5 Activate overnight at 200-250 [deg]C.
7.5.2 Alumina--Either one of two types of alumina, acid or basic,
may be used in the cleanup of sample extracts, provided that the
laboratory can meet the performance specifications for the recovery of
labeled compounds described in Section 9.3. The same type of alumina
must be used for all samples, including those used to demonstrate
initial precision and recovery (Section 9.2) and ongoing precision and
recovery (Section 15.5).
7.5.2.1 Acid alumina--Supelco 19996-6C (or equivalent). Activate by
heating to 130 [deg]C for a minimum of 12 hours.
7.5.2.2 Basic alumina--Supelco 19944-6C (or equivalent). Activate by
heating to 600 [deg]C for a minimum of 24 hours. Alternatively, activate
by heating in a tube furnace at 650-700 [deg]C under an air flow rate of
approximately 400 cc/minute. Do not heat over 700 [deg]C, as this can
lead to reduced capacity for retaining the analytes. Store at 130 [deg]C
in a covered flask. Use within five days of baking.
7.5.3 Carbon.
7.5.3.1 Carbopak C--(Supelco 1-0258, or equivalent).
7.5.3.2 Celite 545--(Supelco 2-0199, or equivalent).
7.5.3.3 Thoroughly mix 9.0 g Carbopak C and 41.0 g Celite 545 to
produce an 18% w/w mixture. Activate the mixture at 130 [deg]C for a
minimum of six hours. Store in a dessicator.
7.5.4 Anthropogenic isolation column--Pack the column in Section
6.7.4.3 from bottom to top with the following:
7.5.4.1 2 g silica gel (Section 7.5.1.1).
7.5.4.2 2 g potassium silicate (Section 7.5.1.4).
7.5.4.3 2 g granular anhydrous sodium sulfate (Section 7.2.1).
7.5.4.4 10 g acid silica gel (Section 7.5.1.2).
7.5.4.5 2 g granular anhydrous sodium sulfate.
7.5.5 Florisil column.
7.5.5.1 Florisil--60-100 mesh, Floridin Corp (or equivalent).
Soxhlet extract in 500 g portions for 24 hours.
7.5.5.2 Insert a glass wool plug into the tapered end of a graduated
serological pipet (Section 6.7.3.2). Pack with 1.5 g (approx 2 mL) of
Florisil topped with approx 1 mL of sodium sulfate (Section 7.2.1) and a
glass wool plug.
7.5.5.3 Activate in an oven at 130-150 [deg]C for a minimum of 24
hours and cool for 30 minutes. Use within 90 minutes of cooling.
7.6 Reference Matrices--Matrices in which the CDDs/CDFs and
interfering compounds are not detected by this method.
7.6.1 Reagent water--Bottled water purchased locally, or prepared by
passage through activated carbon.
7.6.2 High-solids reference matrix--Playground sand or similar
material. Prepared by extraction with methylene chloride and/or baking
at 450 [deg]C for a minimum of four hours.
7.6.3 Paper reference matrix--Glass-fiber filter, Gelman Type A, or
equivalent. Cut paper to simulate the surface area of the paper sample
being tested.
7.6.4 Tissue reference matrix--Corn or other vegetable oil. May be
prepared by extraction with methylene chloride.
7.6.5 Other matrices--This method may be verified on any reference
matrix by performing the tests given in Section 9.2. Ideally, the matrix
should be free of the CDDs/CDFs, but in no case shall the background
level of the CDDs/CDFs in the reference matrix exceed three times the
minimum levels in Table 2. If low background levels of the CDDs/CDFs are
present in the reference matrix, the spike level of the analytes used in
Section 9.2 should be increased to provide a spike-to-background ratio
in the range of 1:1 to 5:1 (Reference 15).
7.7 Standard Solutions--Purchased as solutions or mixtures with
certification to their purity, concentration, and authenticity, or
prepared from materials of known purity and composition. If the chemical
purity is 98% or greater, the weight may be used without correction to
compute the concentration of the standard. When not being used,
standards are stored in the dark at room temperature in screw-capped
vials with fluoropolymer-lined caps. A mark is placed on the vial at the
level of the solution so that solvent loss by evaporation can be
detected. If solvent loss has occurred, the solution should be replaced.
7.8 Stock Solutions.
7.8.1 Preparation--Prepare in nonane per the steps below or purchase
as dilute solutions (Cambridge Isotope Laboratories (CIL), Woburn, MA,
or equivalent). Observe the safety precautions in Section 5, and the
recommendation in Section 5.1.2.
7.8.2 Dissolve an appropriate amount of assayed reference material
in solvent. For example, weigh 1-2 mg of 2,3,7,8-TCDD to three
significant figures in a 10 mL ground-glass-stoppered volumetric flask
and fill to the mark with nonane. After the TCDD is completely
dissolved, transfer the solution to a clean 15 mL vial with
fluoropolymer-lined cap.
7.8.3 Stock standard solutions should be checked for signs of
degradation prior to the
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preparation of calibration or performance test standards. Reference
standards that can be used to determine the accuracy of calibration
standards are available from CIL and may be available from other
vendors.
7.9 PAR Stock Solution
7.9.1 All CDDs/CDFs--Using the solutions in Section 7.8, prepare the
PAR stock solution to contain the CDDs/CDFs at the concentrations shown
in Table 3. When diluted, the solution will become the PAR (Section
7.14).
7.9.2 If only 2,3,7,8-TCDD and 2,3,7,8-TCDF are to be determined,
prepare the PAR stock solution to contain these compounds only.
7.10 Labeled-Compound Spiking Solution.
7.10.1 All CDDs/CDFs--From stock solutions, or from purchased
mixtures, prepare this solution to contain the labeled compounds in
nonane at the concentrations shown in Table 3. This solution is diluted
with acetone prior to use (Section 7.10.3).
7.10.2 If only 2,3,7,8-TCDD and 2,3,7,8-TCDF are to be determined,
prepare the labeled-compound solution to contain these compounds only.
This solution is diluted with acetone prior to use (Section 7.10.3).
7.10.3 Dilute a sufficient volume of the labeled compound solution
(Section 7.10.1 or 7.10.2) by a factor of 50 with acetone to prepare a
diluted spiking solution. Each sample requires 1.0 mL of the diluted
solution, but no more solution should be prepared than can be used in
one day.
7.11 Cleanup Standard--Prepare \37\Cl\4\-2,3,7,8-TCDD in nonane at
the concentration shown in Table 3. The cleanup standard is added to all
extracts prior to cleanup to measure the efficiency of the cleanup
process.
7.12 Internal Standard(s).
7.12.1 All CDDs/CDFs--Prepare the internal standard solution to
contain \13\C\12\-1,2,3,4-TCDD and \13\C\2\-1,2,3,7,8,9-HxCDD in nonane
at the concentration shown in Table 3.
7.12.2 If only 2,3,7,8-TCDD and 2,3,7,8-TCDF are to be determined,
prepare the internal standard solution to contain \13\C\12\-1,2,3,4-TCDD
only.
7.13 Calibration Standards (CS1 through CS5)--Combine the solutions
in Sections 7.9 through 7.12 to produce the five calibration solutions
shown in Table 4 in nonane. These solutions permit the relative response
(labeled to native) and response factor to be measured as a function of
concentration. The CS3 standard is used for calibration verification
(VER). If only 2,3,7,8-TCDD and 2,3,7,8-TCDF are to be determined,
combine the solutions appropriate to these compounds.
7.14 Precision and Recovery (PAR) Standard--Used for determination
of initial (Section 9.2) and ongoing (Section 15.5) precision and
recovery. Dilute 10 [micro]L of the precision and recovery standard
(Section 7.9.1 or 7.9.2) to 2.0 mL with acetone for each sample matrix
for each sample batch. One mL each are required for the blank and OPR
with each matrix in each batch.
7.15 GC Retention Time Window Defining Solution and Isomer
Specificity Test Standard--Used to define the beginning and ending
retention times for the dioxin and furan isomers and to demonstrate
isomer specificity of the GC columns employed for determination of
2,3,7,8-TCDD and 2,3,7,8-TCDF. The standard must contain the compounds
listed in Table 5 (CIL EDF--4006, or equivalent), at a minimum. It is
not necessary to monitor the window-defining compounds if only 2,3,7,8-
TCDD and 2,3,7,8-TCDF are to be determined. In this case, an isomer-
specificity test standard containing the most closely eluted isomers
listed in Table 5 (CIL EDF-4033, or equivalent) may be used.
7.16 QC Check Sample--A QC Check Sample should be obtained from a
source independent of the calibration standards. Ideally, this check
sample would be a certified reference material containing the CDDs/CDFs
in known concentrations in a sample matrix similar to the matrix under
test.
7.17 Stability of Solutions--Standard solutions used for
quantitative purposes (Sections 7.9 through 7.15) should be analyzed
periodically, and should be assayed against reference standards (Section
7.8.3) before further use.
8.0 Sample Collection, Preservation, Storage, and Holding Times
8.1 Collect samples in amber glass containers following conventional
sampling practices (Reference 16). Aqueous samples that flow freely are
collected in refrigerated bottles using automatic sampling equipment.
Solid samples are collected as grab samples using wide-mouth jars.
8.2 Maintain aqueous samples in the dark at 0-4 [deg]C from the time
of collection until receipt at the laboratory. If residual chlorine is
present in aqueous samples, add 80 mg sodium thiosulfate per liter of
water. EPA Methods 330.4 and 330.5 may be used to measure residual
chlorine (Reference 17). If sample pH is greater than 9, adjust to pH 7-
9 with sulfuric acid.
Maintain solid, semi-solid, oily, and mixed-phase samples in the
dark at <4 [deg]C from the time of collection until receipt at the
laboratory.
Store aqueous samples in the dark at 0-4 [deg]C. Store solid, semi-
solid, oily, mixed-phase, and tissue samples in the dark at <-10 [deg]C.
8.3 Fish and Tissue Samples.
8.3.1 Fish may be cleaned, filleted, or processed in other ways in
the field, such that the laboratory may expect to receive whole fish,
fish fillets, or other tissues for analysis.
8.3.2 Fish collected in the field should be wrapped in aluminum
foil, and must be maintained at a temperature less than 4 [deg]C
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from the time of collection until receipt at the laboratory.
8.3.3 Samples must be frozen upon receipt at the laboratory and
maintained in the dark at <-10 [deg]C until prepared. Maintain unused
sample in the dark at <-10 [deg]C.
8.4 Holding Times.
8.4.1 There are no demonstrated maximum holding times associated
with CDDs/CDFs in aqueous, solid, semi-solid, tissues, or other sample
matrices. If stored in the dark at 0-4 [deg]C and preserved as given
above (if required), aqueous samples may be stored for up to one year.
Similarly, if stored in the dark at <-10 [deg]C, solid, semi-solid,
multi-phase, and tissue samples may be stored for up to one year.
8.4.2 Store sample extracts in the dark at <-10 [deg]C until
analyzed. If stored in the dark at <-10 [deg]C, sample extracts may be
stored for up to one year.
9.0 Quality Assurance/Quality Control
9.1 Each laboratory that uses this method is required to operate a
formal quality assurance program (Reference 18). The minimum
requirements of this program consist of an initial demonstration of
laboratory capability, analysis of samples spiked with labeled compounds
to evaluate and document data quality, and analysis of standards and
blanks as tests of continued performance. Laboratory performance is
compared to established performance criteria to determine if the results
of analyses meet the performance characteristics of the method.
If the method is to be applied to sample matrix other than water
(e.g., soils, filter cake, compost, tissue) the most appropriate
alternate matrix (Sections 7.6.2 through 7.6.5) is substituted for the
reagent water matrix (Section 7.6.1) in all performance tests.
9.1.1 The analyst shall make an initial demonstration of the ability
to generate acceptable accuracy and precision with this method. This
ability is established as described in Section 9.2.
9.1.2 In recognition of advances that are occurring in analytical
technology, and to allow the analyst to overcome sample matrix
interferences, the analyst is permitted certain options to improve
separations or lower the costs of measurements. These options include
alternate extraction, concentration, cleanup procedures, and changes in
columns and detectors. Alternate determinative techniques, such as the
substitution of spectroscopic or immuno-assay techniques, and changes
that degrade method performance, are not allowed. If an analytical
technique other than the techniques specified in this method is used,
that technique must have a specificity equal to or better than the
specificity of the techniques in this method for the analytes of
interest.
9.1.2.1 Each time a modification is made to this method, the analyst
is required to repeat the procedure in Section 9.2. If the detection
limit of the method will be affected by the change, the laboratory is
required to demonstrate that the MDL (40 CFR part 136, appendix B) is
lower than one-third the regulatory compliance level or one-third the ML
in this method, whichever is higher. If calibration will be affected by
the change, the analyst must recalibrate the instrument per Section 10.
9.1.2.2 The laboratory is required to maintain records of
modifications made to this method. These records include the following,
at a minimum:
9.1.2.2.1 The names, titles, addresses, and telephone numbers of the
analyst(s) who performed the analyses and modification, and of the
quality control officer who witnessed and will verify the analyses and
modifications.
9.1.2.2.2 A listing of pollutant(s) measured, by name and CAS
Registry number.
9.1.2.2.3 A narrative stating reason(s) for the modifications.
9.1.2.2.4 Results from all quality control (QC) tests comparing the
modified method to this method, including:
(a) Calibration (Section 10.5 through 10.7).
(b) Calibration verification (Section 15.3).
(c) Initial precision and recovery (Section 9.2).
(d) Labeled compound recovery (Section 9.3).
(e) Analysis of blanks (Section 9.5).
(f) Accuracy assessment (Section 9.4).
9.1.2.2.5 Data that will allow an independent reviewer to validate
each determination by tracing the instrument output (peak height, area,
or other signal) to the final result. These data are to include:
(a) Sample numbers and other identifiers.
(b) Extraction dates.
(c) Analysis dates and times.
(d) Analysis sequence/run chronology.
(e) Sample weight or volume (Section 11).
(f) Extract volume prior to each cleanup step (Section 13).
(g) Extract volume after each cleanup step (Section 13).
(h) Final extract volume prior to injection (Section 14).
(i) Injection volume (Section 14.3).
(j) Dilution data, differentiating between dilution of a sample or
extract (Section 17.5).
(k) Instrument and operating conditions.
(l) Column (dimensions, liquid phase, solid support, film thickness,
etc).
(m) Operating conditions (temperatures, temperature program, flow
rates).
(n) Detector (type, operating conditions, etc).
(o) Chromatograms, printer tapes, and other recordings of raw data.
(p) Quantitation reports, data system outputs, and other data to
link the raw data to the results reported.
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9.1.3 Analyses of method blanks are required to demonstrate freedom
from contamination (Section 4.3). The procedures and criteria for
analysis of a method blank are described in Sections 9.5 and 15.6.
9.1.4 The laboratory shall spike all samples with labeled compounds
to monitor method performance. This test is described in Section 9.3.
When results of these spikes indicate atypical method performance for
samples, the samples are diluted to bring method performance within
acceptable limits. Procedures for dilution are given in Section 17.5.
9.1.5 The laboratory shall, on an ongoing basis, demonstrate through
calibration verification and the analysis of the ongoing precision and
recovery aliquot that the analytical system is in control. These
procedures are described in Sections 15.1 through 15.5.
9.1.6 The laboratory shall maintain records to define the quality of
data that is generated. Development of accuracy statements is described
in Section 9.4.
9.2 Initial Precision and Recovery (IPR)--To establish the ability
to generate acceptable precision and recovery, the analyst shall perform
the following operations.
9.2.1 For low solids (aqueous) samples, extract, concentrate, and
analyze four 1 L aliquots of reagent water spiked with the diluted
labeled compound spiking solution (Section 7.10.3) and the precision and
recovery standard (Section 7.14) according to the procedures in Sections
11 through 18. For an alternative sample matrix, four aliquots of the
alternative reference matrix (Section 7.6) are used. All sample
processing steps that are to be used for processing samples, including
preparation (Section 11), extraction (Section 12), and cleanup (Section
13), shall be included in this test.
9.2.2 Using results of the set of four analyses, compute the average
concentration (X) of the extracts in ng/mL and the standard deviation of
the concentration (s) in ng/mL for each compound, by isotope dilution
for CDDs/CDFs with a labeled analog, and by internal standard for
1,2,3,7,8,9-HxCDD, OCDF, and the labeled compounds.
9.2.3 For each CDD/CDF and labeled compound, compare s and X with
the corresponding limits for initial precision and recovery in Table 6.
If only 2,3,7,8-TCDD and 2,3,7,8-TCDF are to be determined, compare s
and X with the corresponding limits for initial precision and recovery
in Table 6a. If s and X for all compounds meet the acceptance criteria,
system performance is acceptable and analysis of blanks and samples may
begin. If, however, any individual s exceeds the precision limit or any
individual X falls outside the range for accuracy, system performance is
unacceptable for that compound. Correct the problem and repeat the test
(Section 9.2).
9.3 The laboratory shall spike all samples with the diluted labeled
compound spiking solution (Section 7.10.3) to assess method performance
on the sample matrix.
9.3.1 Analyze each sample according to the procedures in Sections 11
through 18.
9.3.2 Compute the percent recovery of the labeled compounds and the
cleanup standard using the internal standard method (Section 17.2).
9.3.3 The recovery of each labeled compound must be within the
limits in Table 7 when all 2,3,7,8-substituted CDDs/CDFs are determined,
and within the limits in Table 7a when only 2,3,7,8-TCDD and 2,3,7,8-
TCDF are determined. If the recovery of any compound falls outside of
these limits, method performance is unacceptable for that compound in
that sample. To overcome such difficulties, water samples are diluted
and smaller amounts of soils, sludges, sediments, and other matrices are
reanalyzed per Section 18.4.
9.4 Recovery of labeled compounds from samples should be assessed
and records should be maintained.
9.4.1 After the analysis of five samples of a given matrix type
(water, soil, sludge, pulp, etc.) for which the labeled compounds pass
the tests in Section 9.3, compute the average percent recovery (R) and
the standard deviation of the percent recovery (SR) for the labeled
compounds only. Express the assessment as a percent recovery interval
from R-2SR to R = 2SR for each matrix. For
example, if R = 90% and SR = 10% for five analyses of pulp,
the recovery interval is expressed as 70-110%.
9.4.2 Update the accuracy assessment for each labeled compound in
each matrix on a regular basis (e.g., after each 5-10 new measurements).
9.5 Method Blanks--Reference matrix method blanks are analyzed to
demonstrate freedom from contamination (Section 4.3).
9.5.1 Prepare, extract, clean up, and concentrate a method blank
with each sample batch (samples of the same matrix started through the
extraction process on the same 12-hour shift, to a maximum of 20
samples). The matrix for the method blank shall be similar to sample
matrix for the batch, e.g., a 1 L reagent water blank (Section 7.6.1),
high-solids reference matrix blank (Section 7.6.2), paper matrix blank
(Section 7.6.3); tissue blank (Section 7.6.4) or alternative reference
matrix blank (Section 7.6.5). Analyze the blank immediately after
analysis of the OPR (Section 15.5) to demonstrate freedom from
contamination.
9.5.2 If any 2,3,7,8-substituted CDD/CDF (Table 1) is found in the
blank at greater than the minimum level (Table 2) or one-third the
regulatory compliance level, whichever is greater; or if any potentially
interfering compound is found in the blank at the minimum level for each
level of
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chlorination given in Table 2 (assuming a response factor of 1 relative
to the \13\C12-1,2,3,4-TCDD internal standard for compounds
not listed in Table 1), analysis of samples is halted until the blank
associated with the sample batch shows no evidence of contamination at
this level. All samples must be associated with an uncontaminated method
blank before the results for those samples may be reported for
regulatory compliance purposes.
9.6 QC Check Sample--Analyze the QC Check Sample (Section 7.16)
periodically to assure the accuracy of calibration standards and the
overall reliability of the analytical process. It is suggested that the
QC Check Sample be analyzed at least quarterly.
9.7 The specifications contained in this method can be met if the
apparatus used is calibrated properly and then maintained in a
calibrated state. The standards used for calibration (Section 10),
calibration verification (Section 15.3), and for initial (Section 9.2)
and ongoing (Section 15.5) precision and recovery should be identical,
so that the most precise results will be obtained. A GC/MS instrument
will provide the most reproducible results if dedicated to the settings
and conditions required for the analyses of CDDs/CDFs by this method.
9.8 Depending on specific program requirements, field replicates may
be collected to determine the precision of the sampling technique, and
spiked samples may be required to determine the accuracy of the analysis
when the internal standard method is used.
10.0 Calibration
10.1 Establish the operating conditions necessary to meet the
minimum retention times for the internal standards in Section 10.2.4 and
the relative retention times for the CDDs/CDFs in Table 2.
10.1.1 Suggested GC operating conditions:
Injector temperature: 270 [deg]C
Interface temperature: 290 [deg]C
Initial temperature: 200 [deg]C
Initial time: Two minutes
Temperature program:
200-220 [deg]C, at 5 [deg]C/minute
220 [deg]C for 16 minutes
220-235 [deg]C, at 5 [deg]C/minute
235 [deg]C for seven minutes
235-330 [deg]C, at 5 [deg]C/minute
Note: All portions of the column that connect the GC to the ion
source shall remain at or above the interface temperature specified
above during analysis to preclude condensation of less volatile
compounds.
Optimize GC conditions for compound separation and sensitivity. Once
optimized, the same GC conditions must be used for the analysis of all
standards, blanks, IPR and OPR aliquots, and samples.
10.1.2 Mass spectrometer (MS) resolution--Obtain a selected ion
current profile (SICP) of each analyte in Table 3 at the two exact m/z's
specified in Table 8 and at =10,000 resolving power by
injecting an authentic standard of the CDDs/CDFs either singly or as
part of a mixture in which there is no interference between closely
eluted components.
10.1.2.1 The analysis time for CDDs/CDFs may exceed the long-term
mass stability of the mass spectrometer. Because the instrument is
operated in the high-resolution mode, mass drifts of a few ppm (e.g., 5
ppm in mass) can have serious adverse effects on instrument performance.
Therefore, a mass-drift correction is mandatory and a lock-mass m/z from
PFK is used for drift correction. The lock-mass m/z is dependent on the
exact m/z's monitored within each descriptor, as shown in Table 8. The
level of PFK metered into the HRMS during analyses should be adjusted so
that the amplitude of the most intense selected lock-mass m/z signal
(regardless of the descriptor number) does not exceed 10% of the full-
scale deflection for a given set of detector parameters. Under those
conditions, sensitivity changes that might occur during the analysis can
be more effectively monitored.
Note: Excessive PFK (or any other reference substance) may cause
noise problems and contamination of the ion source necessitating
increased frequency of source cleaning.
10.1.2.2 If the HRMS has the capability to monitor resolution during
the analysis, it is acceptable to terminate the analysis when the
resolution falls below 10,000 to save reanalysis time.
10.1.2.3 Using a PFK molecular leak, tune the instrument to meet the
minimum required resolving power of 10,000 (10% valley) at m/z 304.9824
(PFK) or any other reference signal close to m/z 304 (from TCDF). For
each descriptor (Table 8), monitor and record the resolution and exact
m/z's of three to five reference peaks covering the mass range of the
descriptor. The resolution must be greater than or equal to 10,000, and
the deviation between the exact m/z and the theoretical m/z (Table 8)
for each exact m/z monitored must be less than 5 ppm.
10.2 Ion Abundance Ratios, Minimum Levels, Signal-to-Noise Ratios,
and Absolute Retention Times--Choose an injection volume of either 1
[micro]L or 2 [micro]L, consistent with the capability of the HRGC/HRMS
instrument. Inject a 1 [micro]L or 2 [micro]L aliquot of the CS1
calibration solution (Table 4) using the GC conditions from Section
10.1.1. If only 2,3,7,8-TCDD and 2,3,7,8-TCDF are to be determined, the
operating conditions and specifications below apply to analysis of those
compounds only.
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10.2.1 Measure the SICP areas for each analyte, and compute the ion
abundance ratios at the exact m/z's specified in Table 8. Compare the
computed ratio to the theoretical ratio given in Table 9.
10.2.1.1 The exact m/z's to be monitored in each descriptor are
shown in Table 8. Each group or descriptor shall be monitored in
succession as a function of GC retention time to ensure that all CDDs/
CDFs are detected. Additional m/z's may be monitored in each descriptor,
and the m/z's may be divided among more than the five descriptors listed
in Table 8, provided that the laboratory is able to monitor the m/z's of
all the CDDs/CDFs that may elute from the GC in a given retention-time
window. If only 2,3,7,8-TCDD and 2,3,7,8-TCDF are to be determined, the
descriptors may be modified to include only the exact m/z's for the
tetra-and penta-isomers, the diphenyl ethers, and the lock m/z's.
10.2.1.2 The mass spectrometer shall be operated in a mass-drift
correction mode, using perfluorokerosene (PFK) to provide lock m/z's.
The lock-mass for each group of m/z's is shown in Table 8. Each lock
mass shall be monitored and shall not vary by more than 20% throughout its respective retention time window.
Variations of the lock mass by more than 20% indicate the presence of
coeluting interferences that may significantly reduce the sensitivity of
the mass spectrometer. Reinjection of another aliquot of the sample
extract will not resolve the problem. Additional cleanup of the extract
may be required to remove the interferences.
10.2.2 All CDDs/CDFs and labeled compounds in the CS1 standard shall
be within the QC limits in Table 9 for their respective ion abundance
ratios; otherwise, the mass spectrometer shall be adjusted and this test
repeated until the m/z ratios fall within the limits specified. If the
adjustment alters the resolution of the mass spectrometer, resolution
shall be verified (Section 10.1.2) prior to repeat of the test.
10.2.3 Verify that the HRGC/HRMS instrument meets the minimum levels
in Table 2. The peaks representing the CDDs/CDFs and labeled compounds
in the CS1 calibration standard must have signal-to-noise ratios (S/N)
greater than or equal to 10.0. Otherwise, the mass spectrometer shall be
adjusted and this test repeated until the minimum levels in Table 2 are
met.
10.2.4 The absolute retention time of \13\C12-1,2,3,4-
TCDD (Section 7.12) shall exceed 25.0 minutes on the DB-5 column, and
the retention time of \13\C12-1,2,3,4-TCDD shall exceed 15.0
minutes on the DB-225 column; otherwise, the GC temperature program
shall be adjusted and this test repeated until the above-stated minimum
retention time criteria are met.
2010.3 Retention-Time Windows--Analyze the window defining mixtures
(Section 7.15) using the optimized temperature program in Section 10.1.
Table 5 gives the elution order (first/last) of the window-defining
compounds. If 2,3,7,8-TCDD and 2,3,7,8-TCDF only are to be analyzed,
this test is not required.
10.4 Isomer Specificity.
10.4.1 Analyze the isomer specificity test standards (Section 7.15)
using the procedure in Section 14 and the optimized conditions for
sample analysis (Section 10.1.1).
10.4.2 Compute the percent valley between the GC peaks that elute
most closely to the 2,3,7,8-TCDD and TCDF isomers, on their respective
columns, per Figures 6 and 7.
10.4.3 Verify that the height of the valley between the most closely
eluted isomers and the 2,3,7,8-substituted isomers is less than 25%
(computed as 100 x/y in Figures 6 and 7). If the valley exceeds 25%,
adjust the analytical conditions and repeat the test or replace the GC
column and recalibrate (Sections 10.1.2 through 10.7).
10.5 Calibration by Isotope Dilution--Isotope dilution calibration
is used for the 15 2,3,7,8-substituted CDDs/CDFs for which labeled
compounds are added to samples prior to extraction. The reference
compound for each CDD/CDF compound is shown in Table 2.
10.5.1 A calibration curve encompassing the concentration range is
prepared for each compound to be determined. The relative response (RR)
(labeled to native) vs. concentration in standard solutions is plotted
or computed using a linear regression. Relative response is determined
according to the procedures described below. Five calibration points are
employed.
10.5.2 The response of each CDD/CDF relative to its labeled analog
is determined using the area responses of both the primary and secondary
exact m/z's specified in Table 8, for each calibration standard, as
follows:
[GRAPHIC] [TIFF OMITTED] TR15SE97.002
where:
A1n and A2n = The areas of the primary and
secondary m/z's for the CDD/CDF.
A1l and A2l = The areas of the primary and
secondary m/z's for the labeled compound.
Cl = The concentration of the labeled compound in the
calibration standard (Table 4).
Cn = The concentration of the native compound in the
calibration standard (Table 4).
10.5.3 To calibrate the analytical system by isotope dilution,
inject a volume of calibration standards CS1 through CS5 (Section 7.13
and Table 4) identical to the volume chosen in Section 10.2, using the
procedure in Section 14 and the conditions in Section
[[Page 317]]
10.1.1 and Table 2. Compute the relative response (RR) at each
concentration.
10.5.4 Linearity--If the relative response for any compound is
constant (less than 20% coefficient of variation) over the five-point
calibration range, an averaged relative response may be used for that
compound; otherwise, the complete calibration curve for that compound
shall be used over the five-point calibration range.
10.6 Calibration by Internal Standard--The internal standard method
is applied to determination of 1,2,3,7,8,9-HxCDD (Section 17.1.2), OCDF
(Section 17.1.1), the non 2,3,7,8-substituted compounds, and to the
determination of labeled compounds for intralaboratory statistics
(Sections 9.4 and 15.5.4).
10.6.1 Response factors--Calibration requires the determination of
response factors (RF) defined by the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE97.003
where:
A1s and A2s = The areas of the primary and
secondary m/z's for the CDD/CDF.
A1is and A2is = The areas of the primary and
secondary m/z's for the internal standard.
Cis = The concentration of the internal standard (Table 4).
Cs = The concentration of the compound in the calibration
standard (Table 4).
Note: There is only one m/z for \37\Cl4-2,3,7,8-TCDD. See
Table 8.
10.6.2 To calibrate the analytical system by internal standard,
inject 1.0 [micro]L or 2.0 [micro]L of calibration standards CS1 through
CS5 (Section 7.13 and Table 4) using the procedure in Section 14 and the
conditions in Section 10.1.1 and Table 2. Compute the response factor
(RF) at each concentration.
10.6.3 Linearity--If the response factor (RF) for any compound is
constant (less than 35% coefficient of variation) over the five-point
calibration range, an averaged response factor may be used for that
compound; otherwise, the complete calibration curve for that compound
shall be used over the five-point range.
10.7 Combined Calibration--By using calibration solutions (Section
7.13 and Table 4) containing the CDDs/CDFs and labeled compounds and the
internal standards, a single set of analyses can be used to produce
calibration curves for the isotope dilution and internal standard
methods. These curves are verified each shift (Section 15.3) by
analyzing the calibration verification standard (VER, Table 4).
Recalibration is required if any of the calibration verification
criteria (Section 15.3) cannot be met.
10.8 Data Storage--MS data shall be collected, recorded, and stored.
10.8.1 Data acquisition--The signal at each exact m/z shall be
collected repetitively throughout the monitoring period and stored on a
mass storage device.
10.8.2 Response factors and multipoint calibrations--The data system
shall be used to record and maintain lists of response factors (response
ratios for isotope dilution) and multipoint calibration curves.
Computations of relative standard deviation (coefficient of variation)
shall be used to test calibration linearity. Statistics on initial
performance (Section 9.2) and ongoing performance (Section 15.5) should
be computed and maintained, either on the instrument data system, or on
a separate computer system.
11.0 Sample Preparation
11.1 Sample preparation involves modifying the physical form of the
sample so that the CDDs/CDFs can be extracted efficiently. In general,
the samples must be in a liquid form or in the form of finely divided
solids in order for efficient extraction to take place. Table 10 lists
the phases and suggested quantities for extraction of various sample
matrices.
For samples known or expected to contain high levels of the CDDs/
CDFs, the smallest sample size representative of the entire sample
should be used (see Section 17.5).
For all samples, the blank and IPR/OPR aliquots must be processed
through the same steps as the sample to check for contamination and
losses in the preparation processes.
11.1.1 For samples that contain particles, percent solids and
particle size are determined using the procedures in Sections 11.2 and
11.3, respectively.
11.1.2 Aqueous samples--Because CDDs/CDFs may be bound to suspended
particles, the preparation of aqueous samples is dependent on the solids
content of the sample.
11.1.2.1 Aqueous samples visibly absent particles are prepared per
Section 11.4 and extracted directly using the separatory funnel or SPE
techniques in Sections 12.1 or 12.2, respectively.
11.1.2.2 Aqueous samples containing visible particles and containing
one percent suspended solids or less are prepared using the procedure in
Section 11.4. After preparation, the sample is extracted directly using
the SPE technique in 12.2 or filtered per Section 11.4.3. After
filtration, the particles and filter are extracted using the SDS
procedure in Section 12.3 and the filtrate is extracted using the
separatory funnel procedure in Section 12.1.
11.1.2.3 For aqueous samples containing greater than one percent
solids, a sample aliquot sufficient to provide 10 g of dry solids is
used, as described in Section 11.5.
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11.1.3 Solid samples are prepared using the procedure described in
Section 11.5 followed by extraction via the SDS procedure in Section
12.3.
11.1.4 Multiphase samples--The phase(s) containing the CDDs/CDFs is
separated from the non-CDD/CDF phase using pressure filtration and
centrifugation, as described in Section 11.6. The CDDs/CDFs will be in
the organic phase in a multiphase sample in which an organic phase
exists.
11.1.5 Procedures for grinding, homogenization, and blending of
various sample phases are given in Section 11.7.
11.1.6 Tissue samples--Preparation procedures for fish and other
tissues are given in Section 11.8.
11.2 Determination of Percent Suspended Solids.
Note: This aliquot is used for determining the solids content of the
sample, not for determination of CDDs/CDFs.
11.2.1 Aqueous liquids and multi-phase samples consisting of mainly
an aqueous phase.
11.2.1.1 Dessicate and weigh a GF/D filter (Section 6.5.3) to three
significant figures.
11.2.1.2 Filter 10.0 0.02 mL of well-mixed
sample through the filter.
11.2.1.3 Dry the filter a minimum of 12 hours at 110 5 [deg]C and cool in a dessicator.
11.2.1.4 Calculate percent solids as follows:
[GRAPHIC] [TIFF OMITTED] TR15SE97.004
11.2.2 Non-aqueous liquids, solids, semi-solid samples, and multi-
phase samples in which the main phase is not aqueous; but not tissues.
11.2.2.1 Weigh 5-10 g of sample to three significant figures in a
tared beaker.
11.2.2.2 Dry a minimum of 12 hours at 110 5
[deg]C, and cool in a dessicator.
11.2.2.3 Calculate percent solids as follows:
[GRAPHIC] [TIFF OMITTED] TR15SE97.005
11.3 Determination of Particle Size.
11.3.1 Spread the dried sample from Section 11.2.2.2 on a piece of
filter paper or aluminum foil in a fume hood or glove box.
11.3.2 Estimate the size of the particles in the sample. If the size
of the largest particles is greater than 1 mm, the particle size must be
reduced to 1 mm or less prior to extraction using the procedures in
Section 11.7.
11.4 Preparation of Aqueous Samples Containing 1% Suspended Solids
or Less.
11.4.1 Aqueous samples visibly absent particles are prepared per the
procedure below and extracted directly using the separatory funnel or
SPE techniques in Sections 12.1 or 12.2, respectively. Aqueous samples
containing visible particles and one percent suspended solids or less
are prepared using the procedure below and extracted using either the
SPE technique in Section 12.2 or further prepared using the filtration
procedure in Section 11.4.3. The filtration procedure is followed by SDS
extraction of the filter and particles (Section 12.3) and separatory
funnel extraction of the filtrate (Section 12.1). The SPE procedure is
followed by SDS extraction of the filter and disk.
11.4.2 Preparation of sample and QC aliquots.
11.4.2.1 Mark the original level of the sample on the sample bottle
for reference. Weigh the sample plus bottle to 1.
11.4.2.2 Spike 1.0 mL of the diluted labeled-compound spiking
solution (Section 7.10.3) into the sample bottle. Cap the bottle and mix
the sample by careful shaking. Allow the sample to equilibrate for one
to two hours, with occasional shaking.
11.4.2.3 For each sample or sample batch (to a maximum of 20
samples) to be extracted during the same 12-hour shift, place two 1.0 L
aliquots of reagent water in clean sample bottles or flasks.
11.4.2.4 Spike 1.0 mL of the diluted labeled-compound spiking
solution (Section 7.10.3) into both reagent water aliquots. One of these
aliquots will serve as the method blank.
11.4.2.5 Spike 1.0 mL of the PAR standard (Section 7.14) into the
remaining reagent water aliquot. This aliquot will serve as the OPR
(Section 15.5).
11.4.2.6 If SPE is to be used, add 5 mL of methanol to the sample,
cap and shake the
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sample to mix thoroughly, and proceed to Section 12.2 for extraction. If
SPE is not to be used, and the sample is visibly absent particles,
proceed to Section 12.1 for extraction. If SPE is not to be used and the
sample contains visible particles, proceed to the following section for
filtration of particles.
11.4.3 Filtration of particles.
11.4.3.1 Assemble a Buchner funnel (Section 6.5.5) on top of a clean
filtration flask. Apply vacuum to the flask, and pour the entire
contents of the sample bottle through a glass-fiber filter (Section
6.5.6) in the Buchner funnel, swirling the sample remaining in the
bottle to suspend any particles.
11.4.3.2 Rinse the sample bottle twice with approximately 5 mL
portions of reagent water to transfer any remaining particles onto the
filter.
11.4.3.3 Rinse any particles off the sides of the Buchner funnel
with small quantities of reagent water.
11.4.3.4 Weigh the empty sample bottle to 1 g.
Determine the weight of the sample by difference. Save the bottle for
further use.
11.4.3.5 Extract the filtrate using the separatory funnel procedure
in Section 12.1.
11.4.3.6 Extract the filter containing the particles using the SDS
procedure in Section 12.3.
11.5 Preparation of Samples Containing Greater Than 1% Solids.
11.5.1 Weigh a well-mixed aliquot of each sample (of the same matrix
type) sufficient to provide 10 g of dry solids (based on the solids
determination in Section 11.2) into a clean beaker or glass jar.
11.5.2 Spike 1.0 mL of the diluted labeled compound spiking solution
(Section 7.10.3) into the sample.
11.5.3 For each sample or sample batch (to a maximum of 20 samples)
to be extracted during the same 12-hour shift, weigh two 10 g aliquots
of the appropriate reference matrix (Section 7.6) into clean beakers or
glass jars.
11.5.4 Spike 1.0 mL of the diluted labeled compound spiking solution
(Section 7.10.3) into each reference matrix aliquot. One aliquot will
serve as the method blank. Spike 1.0 mL of the PAR standard (Section
7.14) into the other reference matrix aliquot. This aliquot will serve
as the OPR (Section 15.5).
11.5.5 Stir or tumble and equilibrate the aliquots for one to two
hours.
11.5.6 Decant excess water. If necessary to remove water, filter the
sample through a glass-fiber filter and discard the aqueous liquid.
11.5.7 If particles 1mm are present in the sample (as
determined in Section 11.3.2), spread the sample on clean aluminum foil
in a hood. After the sample is dry, grind to reduce the particle size
(Section 11.7).
11.5.8 Extract the sample and QC aliquots using the SDS procedure in
Section 12.3.
11.6 Multiphase Samples.
11.6.1 Using the percent solids determined in Section 11.2.1 or
11.2.2, determine the volume of sample that will provide 10 g of solids,
up to 1 L of sample.
11.6.2 Pressure filter the amount of sample determined in Section
11.6.1 through Whatman GF/D glass-fiber filter paper (Section 6.5.3).
Pressure filter the blank and OPR aliquots through GF/D papers also. If
necessary to separate the phases and/or settle the solids, centrifuge
these aliquots prior to filtration.
11.6.3 Discard any aqueous phase (if present). Remove any non-
aqueous liquid present and reserve the maximum amount filtered from the
sample (Section 11.6.1) or 10 g, whichever is less, for combination with
the solid phase (Section 12.3.5).
11.6.4 If particles 1mm are present in the sample (as
determined in Section 11.3.2) and the sample is capable of being dried,
spread the sample and QC aliquots on clean aluminum foil in a hood.
After the aliquots are dry or if the sample cannot be dried, reduce the
particle size using the procedures in Section 11.7 and extract the
reduced particles using the SDS procedure in Section 12.3. If particles
1mm are not present, extract the particles and filter in the
sample and QC aliquots directly using the SDS procedure in Section 12.3.
11.7 Sample grinding, homogenization, or blending--Samples with
particle sizes greater than 1 mm (as determined in Section 11.3.2) are
subjected to grinding, homogenization, or blending. The method of
reducing particle size to less than 1 mm is matrix-dependent. In
general, hard particles can be reduced by grinding with a mortar and
pestle. Softer particles can be reduced by grinding in a Wiley mill or
meat grinder, by homogenization, or in a blender.
11.7.1 Each size-reducing preparation procedure on each matrix shall
be verified by running the tests in Section 9.2 before the procedure is
employed routinely.
11.7.2 The grinding, homogenization, or blending procedures shall be
carried out in a glove box or fume hood to prevent particles from
contaminating the work environment.
11.7.3 Grinding--Certain papers and pulps, slurries, and amorphous
solids can be ground in a Wiley mill or heavy duty meat grinder. In some
cases, reducing the temperature of the sample to freezing or to dry ice
or liquid nitrogen temperatures can aid in the grinding process. Grind
the sample aliquots from Section 11.5.7 or 11.6.4 in a clean grinder. Do
not allow the sample temperature to exceed 50 [deg]C. Grind the blank
and reference matrix aliquots using a clean grinder.
11.7.4 Homogenization or blending--Particles that are not ground
effectively, or particles greater than 1 mm in size after grinding, can
often be reduced in size by high speed homogenization or blending.
Homogenize and/or blend the particles or filter from
[[Page 320]]
Section 11.5.7 or 11.6.4 for the sample, blank, and OPR aliquots.
11.7.5 Extract the aliquots using the SDS procedure in Section 12.3.
11.8 Fish and Other Tissues--Prior to processing tissue samples, the
laboratory must determine the exact tissue to be analyzed. Common
requests for analysis of fish tissue include whole fish--skin on, whole
fish--skin removed, edible fish fillets (filleted in the field or by the
laboratory), specific organs, and other portions. Once the appropriate
tissue has been determined, the sample must be homogenized.
11.8.1 Homogenization.
11.8.1.1 Samples are homogenized while still frozen, where
practical. If the laboratory must dissect the whole fish to obtain the
appropriate tissue for analysis, the unused tissues may be rapidly
refrozen and stored in a clean glass jar for subsequent use.
11.8.1.2 Each analysis requires 10 g of tissue (wet weight).
Therefore, the laboratory should homogenize at least 20 g of tissue to
allow for re-extraction of a second aliquot of the same homogenized
sample, if re-analysis is required. When whole fish analysis is
necessary, the entire fish is homogenized.
11.8.1.3 Homogenize the sample in a tissue homogenizer (Section
6.3.3) or grind in a meat grinder (Section 6.3.4). Cut tissue too large
to feed into the grinder into smaller pieces. To assure homogeneity,
grind three times.
11.8.1.4 Transfer approximately 10 g (wet weight) of homogenized
tissue to a clean, tared, 400-500 mL beaker. For the alternate HCl
digestion/extraction, transfer the tissue to a clean, tared 500-600 mL
wide-mouth bottle. Record the weight to the nearest 10 mg.
11.8.1.5 Transfer the remaining homogenized tissue to a clean jar
with a fluoropolymer-lined lid. Seal the jar and store the tissue at <-
10 [deg]C. Return any tissue that was not homogenized to its original
container and store at <-10 [deg]C.
11.8.2 QC aliquots.
11.8.2.1 Prepare a method blank by adding approximately 10 g of the
oily liquid reference matrix (Section 7.6.4) to a 400-500 mL beaker. For
the alternate HCl digestion/extraction, add the reference matrix to a
500-600 mL wide-mouth bottle. Record the weight to the nearest 10 mg.
11.8.2.2 Prepare a precision and recovery aliquot by adding
approximately 10 g of the oily liquid reference matrix (Section 7.6.4)
to a separate 400-500 mL beaker or wide-mouth bottle, depending on the
extraction procedure to be used. Record the weight to the nearest 10 mg.
If the initial precision and recovery test is to be performed, use four
aliquots; if the ongoing precision and recovery test is to be performed,
use a single aliquot.
11.8.3 Spiking
11.8.3.1 Spike 1.0 mL of the labeled compound spiking solution
(Section 7.10.3) into the sample, blank, and OPR aliquot.
11.8.3.2 Spike 1.0 mL of the PAR standard (Section 7.14) into the
OPR aliquot.
11.8.4 Extract the aliquots using the procedures in Section 12.4.
12.0 Extraction and Concentration
Extraction procedures include separatory funnel (Section 12.1) and
solid phase (Section 12.2) for aqueous liquids; Soxhlet/Dean-Stark
(Section 12.3) for solids, filters, and SPE disks; and Soxhlet
extraction (Section 12.4.1) and HCl digestion (Section 12.4.2) for
tissues. Acid/base back-extraction (Section 12.5) is used for initial
cleanup of extracts.
Macro-concentration procedures include rotary evaporation (Section
12.6.1), heating mantle (Section 12.6.2), and Kuderna-Danish (K-D)
evaporation (Section 12.6.3). Micro-concentration uses nitrogen blowdown
(Section 12.7).
12.1 Separatory funnel extraction of filtrates and of aqueous
samples visibly absent particles.
12.1.1 Pour the spiked sample (Section 11.4.2.2) or filtrate
(Section 11.4.3.5) into a 2 L separatory funnel. Rinse the bottle or
flask twice with 5 mL of reagent water and add these rinses to the
separatory funnel.
12.1.2 Add 60 mL methylene chloride to the empty sample bottle
(Section 12.1.1), seal, and shake 60 seconds to rinse the inner surface.
Transfer the solvent to the separatory funnel, and extract the sample by
shaking the funnel for two minutes with periodic venting. Allow the
organic layer to separate from the aqueous phase for a minimum of 10
minutes. If an emulsion forms and is more than one-third the volume of
the solvent layer, employ mechanical techniques to complete the phase
separation (see note below). Drain the methylene chloride extract
through a solvent-rinsed glass funnel approximately one-half full of
granular anhydrous sodium sulfate (Section 7.2.1) supported on clean
glass-fiber paper into a solvent-rinsed concentration device (Section
12.6).
Note: If an emulsion forms, the analyst must employ mechanical
techniques to complete the phase separation. The optimum technique
depends upon the sample, but may include stirring, filtration through
glass wool, use of phase separation paper, centrifugation, use of an
ultrasonic bath with ice, addition of NaCl, or other physical methods.
Alternatively, solid-phase or other extraction techniques may be used to
prevent emulsion formation. Any alternative technique is acceptable so
long as the requirements in Section 9 are met.
Experience with aqueous samples high in dissolved organic materials
(e.g., paper mill effluents) has shown that acidification of the
[[Page 321]]
sample prior to extraction may reduce the formation of emulsions. Paper
industry methods suggest that the addition of up to 400 mL of ethanol to
a 1 L effluent sample may also reduce emulsion formation. However,
studies by EPA suggest that the effect may be a result of sample
dilution, and that the addition of reagent water may serve the same
function. Mechanical techniques may still be necessary to complete the
phase separation. If either acidification or addition of ethanol is
utilized, the laboratory must perform the startup tests described in
Section 9.2 using the same techniques.
12.1.3 Extract the water sample two more times with 60 mL portions
of methylene chloride. Drain each portion through the sodium sulfate
into the concentrator. After the third extraction, rinse the separatory
funnel with at least 20 mL of methylene chloride, and drain this rinse
through the sodium sulfate into the concentrator. Repeat this rinse at
least twice. Set aside the funnel with sodium sulfate if the extract is
to be combined with the extract from the particles.
12.1.4 Concentrate the extract using one of the macro-concentration
procedures in Section 12.6.
12.1.4.1 If the extract is from a sample visibly absent particles
(Section 11.1.2.1), adjust the final volume of the concentrated extract
to approximately 10 mL with hexane, transfer to a 250 mL separatory
funnel, and back-extract using the procedure in Section 12.5.
12.1.4.2 If the extract is from the aqueous filtrate (Section
11.4.3.5), set aside the concentration apparatus for addition of the SDS
extract from the particles (Section 12.3.9.1.2).
12.2 SPE of Samples Containing Less Than 1% Solids (References 19-
20).
12.2.1 Disk preparation.
12.2.1.1 Place an SPE disk on the base of the filter holder (Figure
4) and wet with toluene. While holding a GMF 150 filter above the SPE
disk with tweezers, wet the filter with toluene and lay the filter on
the SPE disk, making sure that air is not trapped between the filter and
disk. Clamp the filter and SPE disk between the 1 L glass reservoir and
the vacuum filtration flask.
12.2.1.2 Rinse the sides of the filtration flask with approx 15 mL
of toluene using a squeeze bottle or syringe. Apply vacuum momentarily
until a few drops appear at the drip tip. Release the vacuum and allow
the filter/disk to soak for approx one minute. Apply vacuum and draw all
of the toluene through the filter/disk. Repeat the wash step with approx
15 mL of acetone and allow the filter/disk to air dry.
12.2.1.3 Re-wet the filter/disk with approximately 15 mL of
methanol, allowing the filter/disk to soak for approximately one minute.
Pull the methanol through the filter/disk using the vacuum, but retain a
layer of methanol approximately 1 mm thick on the filter. Do not allow
the disk to go dry from this point until the end of the extraction.
12.2.1.4 Rinse the filter/disk with two 50-mL portions of reagent
water by adding the water to the reservoir and pulling most through,
leaving a layer of water on the surface of the filter.
12.2.2 Extraction.
12.2.2.1 Pour the spiked sample (Section 11.4.2.2), blank (Section
11.4.2.4), or IPR/OPR aliquot (Section 11.4.2.5) into the reservoir and
turn on the vacuum to begin the extraction. Adjust the vacuum to
complete the extraction in no less than 10 minutes. For samples
containing a high concentration of particles (suspended solids),
filtration times may be eight hours or longer.
12.2.2.2 Before all of the sample has been pulled through the
filter/disk, rinse the sample bottle with approximately 50 mL of reagent
water to remove any solids, and pour into the reservoir. Pull through
the filter/disk. Use additional reagent water rinses until all visible
solids are removed.
12.2.2.3 Before all of the sample and rinses have been pulled
through the filter/disk, rinse the sides of the reservoir with small
portions of reagent water.
12.2.2.4 Allow the filter/disk to dry, then remove the filter and
disk and place in a glass Petri dish. Extract the filter and disk per
Section 12.3.
12.3 SDS Extraction of Samples Containing Particles, and of Filters
and/or Disks.
12.3.1 Charge a clean extraction thimble (Section 6.4.2.2) with 5.0
g of 100/200 mesh silica (Section 7.5.1.1) topped with 100 g of quartz
sand (Section 7.3.2).
Note: Do not disturb the silica layer throughout the extraction
process.
12.3.2 Place the thimble in a clean extractor. Place 30-40 mL of
toluene in the receiver and 200-250 mL of toluene in the flask.
12.3.3 Pre-extract the glassware by heating the flask until the
toluene is boiling. When properly adjusted, one to two drops of toluene
will fall per second from the condenser tip into the receiver. Extract
the apparatus for a minimum of three hours.
12.3.4 After pre-extraction, cool and disassemble the apparatus.
Rinse the thimble with toluene and allow to air dry.
12.3.5 Load the wet sample, filter, and/or disk from Section
11.4.3.6, 11.5.8, 11.6.4, 11.7.3, 11.7.4, or 12.2.2.4 and any nonaqueous
liquid from Section 11.6.3 into the thimble and manually mix into the
sand layer with a clean metal spatula, carefully breaking up any large
lumps of sample.
12.3.6 Reassemble the pre-extracted SDS apparatus, and add a fresh
charge of toluene to the receiver and reflux flask. Apply power
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to the heating mantle to begin refluxing. Adjust the reflux rate to
match the rate of percolation through the sand and silica beds until
water removal lessens the restriction to toluene flow. Frequently check
the apparatus for foaming during the first two hours of extraction. If
foaming occurs, reduce the reflux rate until foaming subsides.
12.3.7 Drain the water from the receiver at one to two hours and
eight to nine hours, or sooner if the receiver fills with water. Reflux
the sample for a total of 16-24 hours. Cool and disassemble the
apparatus. Record the total volume of water collected.
12.3.8 Remove the distilling flask. Drain the water from the Dean-
Stark receiver and add any toluene in the receiver to the extract in the
flask.
12.3.9 Concentrate the extract using one of the macro-concentration
procedures in Section 12.6 per the following:
12.3.9.1 Extracts from the particles in an aqueous sample containing
less than 1% solids (Section 11.4.3.6).
12.3.9.1.1 Concentrate the extract to approximately 5 mL using the
rotary evaporator or heating mantle procedures in Section 12.6.1 or
12.6.2.
12.3.9.1.2 Quantitatively transfer the extract through the sodium
sulfate (Section 12.1.3) into the apparatus that was set aside (Section
12.1.4.2) and reconcentrate to the level of the toluene.
12.3.9.1.3 Adjust to approximately 10 mL with hexane, transfer to a
250 mL separatory funnel, and proceed with back-extraction (Section
12.5).
12.3.9.2 Extracts from particles (Sections 11.5 through 11.6) or
from the SPE filter and disk (Section 12.2.2.4)--Concentrate to
approximately 10 mL using the rotary evaporator or heating mantle
(Section 12.6.1 or 12.6.2), transfer to a 250 mL separatory funnel, and
proceed with back-extraction (Section 12.5).
12.4 Extraction of Tissue--Two procedures are provided for tissue
extraction.
12.4.1 Soxhlet extraction (Reference 21).
12.4.1.1 Add 30-40 g of powdered anhydrous sodium sulfate to each of
the beakers (Section 11.8.4) and mix thoroughly. Cover the beakers with
aluminum foil and allow to equilibrate for 12-24 hours. Remix prior to
extraction to prevent clumping.
12.4.1.2 Assemble and pre-extract the Soxhlet apparatus per Sections
12.3.1 through 12.3.4, except use the methylene chloride:hexane (1:1)
mixture for the pre-extraction and rinsing and omit the quartz sand. The
Dean-Stark moisture trap may also be omitted, if desired.
12.4.1.3 Reassemble the pre-extracted Soxhlet apparatus and add a
fresh charge of methylene chloride:hexane to the reflux flask.
12.4.1.4 Transfer the sample/sodium sulfate mixture (Section
12.4.1.1) to the Soxhlet thimble, and install the thimble in the Soxhlet
apparatus.
12.4.1.5 Rinse the beaker with several portions of solvent mixture
and add to the thimble. Fill the thimble/receiver with solvent. Extract
for 18-24 hours.
12.4.1.6 After extraction, cool and disassemble the apparatus.
12.4.1.7 Quantitatively transfer the extract to a macro-
concentration device (Section 12.6), and concentrate to near dryness.
Set aside the concentration apparatus for re-use.
12.4.1.8 Complete the removal of the solvent using the nitrogen
blowdown procedure (Section 12.7) and a water bath temperature of 60
[deg]C. Weigh the receiver, record the weight, and return the receiver
to the blowdown apparatus, concentrating the residue until a constant
weight is obtained.
12.4.1.9 Percent lipid determination--The lipid content is
determined by extraction of tissue with the same solvent system
(methylene chloride:hexane) that was used in EPA's National Dioxin Study
(Reference 22) so that lipid contents are consistent with that study.
12.4.1.9.1 Redissolve the residue in the receiver in hexane and
spike 1.0 mL of the cleanup standard (Section 7.11) into the solution.
12.4.1.9.2 Transfer the residue/hexane to the anthropogenic
isolation column (Section 13.7.1) or bottle for the acidified silica gel
batch cleanup (Section 13.7.2), retaining the boiling chips in the
concentration apparatus. Use several rinses to assure that all material
is transferred. If necessary, sonicate or heat the receiver slightly to
assure that all material is re-dissolved. Allow the receiver to dry.
Weigh the receiver and boiling chips.
12.4.1.9.3 Calculate the lipid content to the nearest three
significant figures as follows:
[GRAPHIC] [TIFF OMITTED] TR15SE97.006
12.4.1.9.4 It is not necessary to determine the lipid content of the
blank, IPR, or OPR aliquots.
12.4.2 HCl digestion/extraction and concentration (References 23-
26).
12.4.2.1 Add 200 mL of 6 N HCl and 200 mL of methylene
chloride:hexane (1:1) to the sample and QC aliquots (Section 11.8.4).
12.4.2.2 Cap and shake each bottle one to three times. Loosen the
cap in a hood to vent excess pressure. Shake each bottle for 10-30
seconds and vent.
12.4.2.3 Tightly cap and place on shaker. Adjust the shaker action
and speed so that the acid, solvent, and tissue are in constant motion.
However, take care to avoid such violent action that the bottle may be
dislodged from the shaker. Shake for 12-24 hours.
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12.4.2.4 After digestion, remove the bottles from the shaker. Allow
the bottles to stand so that the solvent and acid layers separate.
12.4.2.5 Decant the solvent through a glass funnel with glass-fiber
filter (Sections 6.5.2 through 6.5.3) containing approximately 10 g of
granular anhydrous sodium sulfate (Section 7.2.1) into a macro-
concentration apparatus (Section 12.6). Rinse the contents of the bottle
with two 25 mL portions of hexane and pour through the sodium sulfate
into the apparatus.
12.4.2.6 Concentrate the solvent to near dryness using a macro-
concentration procedure (Section 12.6).
12.4.2.7 Complete the removal of the solvent using the nitrogen
blowdown apparatus (Section 12.7) and a water bath temperature of 60
[deg]C. Weigh the receiver, record the weight, and return the receiver
to the blowdown apparatus, concentrating the residue until a constant
weight is obtained.
12.4.2.8 Percent lipid determination--The lipid content is
determined in the same solvent system [methylene chloride:hexane (1:1)]
that was used in EPA's National Dioxin Study (Reference 22) so that
lipid contents are consistent with that study.
12.4.2.8.1 Redissolve the residue in the receiver in hexane and
spike 1.0 mL of the cleanup standard (Section 7.11) into the solution.
12.4.2.8.2 Transfer the residue/hexane to the narrow-mouth 100-200
mL bottle retaining the boiling chips in the receiver. Use several
rinses to assure that all material is transferred, to a maximum hexane
volume of approximately 70 mL. Allow the receiver to dry. Weigh the
receiver and boiling chips.
12.4.2.8.3 Calculate the percent lipid per Section 12.4.1.9.3. It is
not necessary to determine the lipid content of the blank, IPR, or OPR
aliquots.
12.4.2.9 Clean up the extract per Section 13.7.3.
12.5 Back-Extraction with Base and Acid.
12.5.1 Spike 1.0 mL of the cleanup standard (Section 7.11) into the
separatory funnels containing the sample and QC extracts from Section
12.1.4.1, 12.3.9.1.3, or 12.3.9.2.
12.5.2 Partition the extract against 50 mL of potassium hydroxide
solution (Section 7.1.1). Shake for two minutes with periodic venting
into a hood. Remove and discard the aqueous layer. Repeat the base
washing until no color is visible in the aqueous layer, to a maximum of
four washings. Minimize contact time between the extract and the base to
prevent degradation of the CDDs/CDFs. Stronger potassium hydroxide
solutions may be employed for back-extraction, provided that the
laboratory meets the specifications for labeled compound recovery and
demonstrates acceptable performance using the procedure in Section 9.2.
12.5.3 Partition the extract against 50 mL of sodium chloride
solution (Section 7.1.4) in the same way as with base. Discard the
aqueous layer.
12.5.4 Partition the extract against 50 mL of sulfuric acid (Section
7.1.2) in the same way as with base. Repeat the acid washing until no
color is visible in the aqueous layer, to a maximum of four washings.
12.5.5 Repeat the partitioning against sodium chloride solution and
discard the aqueous layer.
12.5.6 Pour each extract through a drying column containing 7-10 cm
of granular anhydrous sodium sulfate (Section 7.2.1). Rinse the
separatory funnel with 30-50 mL of solvent, and pour through the drying
column. Collect each extract in a round-bottom flask. Re-concentrate the
sample and QC aliquots per Sections 12.6 through 12.7, and clean up the
samples and QC aliquots per Section 13.
12.6 Macro-Concentration--Extracts in toluene are concentrated using
a rotary evaporator or a heating mantle; extracts in methylene chloride
or hexane are concentrated using a rotary evaporator, heating mantle, or
Kuderna-Danish apparatus.
12.6.1 Rotary evaporation--Concentrate the extracts in separate
round-bottom flasks.
12.6.1.1 Assemble the rotary evaporator according to manufacturer's
instructions, and warm the water bath to 45 [deg]C. On a daily basis,
preclean the rotary evaporator by concentrating 100 mL of clean
extraction solvent through the system. Archive both the concentrated
solvent and the solvent in the catch flask for a contamination check if
necessary. Between samples, three 2-3 mL aliquots of solvent should be
rinsed down the feed tube into a waste beaker.
12.6.1.2 Attach the round-bottom flask containing the sample extract
to the rotary evaporator. Slowly apply vacuum to the system, and begin
rotating the sample flask.
12.6.1.3 Lower the flask into the water bath, and adjust the speed
of rotation and the temperature as required to complete concentration in
15-20 minutes. At the proper rate of concentration, the flow of solvent
into the receiving flask will be steady, but no bumping or visible
boiling of the extract will occur.
Note: If the rate of concentration is too fast, analyte loss may
occur.
12.6.1.4 When the liquid in the concentration flask has reached an
apparent volume of approximately 2 mL, remove the flask from the water
bath and stop the rotation. Slowly and carefully admit air into the
system. Be sure not to open the valve so quickly that the sample is
blown out of the flask. Rinse the feed tube with approximately 2 mL of
solvent.
[[Page 324]]
12.6.1.5 Proceed to Section 12.6.4 for preparation for back-
extraction or micro-concentration and solvent exchange.
12.6.2 Heating mantle--Concentrate the extracts in separate round-
bottom flasks.
12.6.2.1 Add one or two clean boiling chips to the round-bottom
flask, and attach a three-ball macro Snyder column. Prewet the column by
adding approximately 1 mL of solvent through the top. Place the round-
bottom flask in a heating mantle, and apply heat as required to complete
the concentration in 15-20 minutes. At the proper rate of distillation,
the balls of the column will actively chatter, but the chambers will not
flood.
12.6.2.2 When the liquid has reached an apparent volume of
approximately 10 mL, remove the round-bottom flask from the heating
mantle and allow the solvent to drain and cool for at least 10 minutes.
Remove the Snyder column and rinse the glass joint into the receiver
with small portions of solvent.
12.6.2.3 Proceed to Section 12.6.4 for preparation for back-
extraction or micro-concentration and solvent exchange.
12.6.3 Kuderna-Danish (K-D)--Concentrate the extracts in separate
500 mL K-D flasks equipped with 10 mL concentrator tubes. The K-D
technique is used for solvents such as methylene chloride and hexane.
Toluene is difficult to concentrate using the K-D technique unless a
water bath fed by a steam generator is used.
12.6.3.1 Add one to two clean boiling chips to the receiver. Attach
a three-ball macro Snyder column. Prewet the column by adding
approximately 1 mL of solvent through the top. Place the K-D apparatus
in a hot water bath so that the entire lower rounded surface of the
flask is bathed with steam.
12.6.3.2 Adjust the vertical position of the apparatus and the water
temperature as required to complete the concentration in 15-20 minutes.
At the proper rate of distillation, the balls of the column will
actively chatter but the chambers will not flood.
12.6.3.3 When the liquid has reached an apparent volume of 1 mL,
remove the K-D apparatus from the bath and allow the solvent to drain
and cool for at least 10 minutes. Remove the Snyder column and rinse the
flask and its lower joint into the concentrator tube with 1-2 mL of
solvent. A 5 mL syringe is recommended for this operation.
12.6.3.4 Remove the three-ball Snyder column, add a fresh boiling
chip, and attach a two-ball micro Snyder column to the concentrator
tube. Prewet the column by adding approximately 0.5 mL of solvent
through the top. Place the apparatus in the hot water bath.
12.6.3.5 Adjust the vertical position and the water temperature as
required to complete the concentration in 5-10 minutes. At the proper
rate of distillation, the balls of the column will actively chatter but
the chambers will not flood.
12.6.3.6 When the liquid reaches an apparent volume of 0.5 mL,
remove the apparatus from the water bath and allow to drain and cool for
at least 10 minutes.
12.6.3.7 Proceed to 12.6.4 for preparation for back-extraction or
micro-concentration and solvent exchange.
12.6.4 Preparation for back-extraction or micro-concentration and
solvent exchange.
12.6.4.1 For back-extraction (Section 12.5), transfer the extract to
a 250 mL separatory funnel. Rinse the concentration vessel with small
portions of hexane, adjust the hexane volume in the separatory funnel to
10-20 mL, and proceed to back-extraction (Section 12.5).
12.6.4.2 For determination of the weight of residue in the extract,
or for clean-up procedures other than back-extraction, transfer the
extract to a blowdown vial using two to three rinses of solvent. Proceed
with micro-concentration and solvent exchange (Section 12.7).
12.7 Micro-Concentration and Solvent Exchange.
12.7.1 Extracts to be subjected to GPC or HPLC cleanup are exchanged
into methylene chloride. Extracts to be cleaned up using silica gel,
alumina, carbon, and/or Florisil are exchanged into hexane.
12.7.2 Transfer the vial containing the sample extract to a nitrogen
blowdown device. Adjust the flow of nitrogen so that the surface of the
solvent is just visibly disturbed.
Note: A large vortex in the solvent may cause analyte loss.
12.7.3 Lower the vial into a 45 [deg]C water bath and continue
concentrating.
12.7.3.1 If the extract is to be concentrated to dryness for weight
determination (Sections 12.4.1.8, 12.4.2.7, and 13.7.1.4), blow dry
until a constant weight is obtained.
12.7.3.2 If the extract is to be concentrated for injection into the
GC/MS or the solvent is to be exchanged for extract cleanup, proceed as
follows:
12.7.4 When the volume of the liquid is approximately 100 L, add 2-3
mL of the desired solvent (methylene chloride for GPC and HPLC, or
hexane for the other cleanups) and continue concentration to
approximately 100 [micro]L. Repeat the addition of solvent and
concentrate once more.
12.7.5 If the extract is to be cleaned up by GPC, adjust the volume
of the extract to 5.0 mL with methylene chloride. If the extract is to
be cleaned up by HPLC, further concentrate the extract to 30 [micro]L.
Proceed with GPC or HPLC cleanup (Section 13.2 or 13.6, respectively).
12.7.6 If the extract is to be cleaned up by column chromatography
(alumina, silica gel, Carbopak/Celite, or Florisil), bring the final
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volume to 1.0 mL with hexane. Proceed with column cleanups (Sections
13.3 through 13.5 and 13.8).
12.7.7 If the extract is to be concentrated for injection into the
GC/MS (Section 14), quantitatively transfer the extract to a 0.3 mL
conical vial for final concentration, rinsing the larger vial with
hexane and adding the rinse to the conical vial. Reduce the volume to
approximately 100 [micro]L. Add 10 [micro]L of nonane to the vial, and
evaporate the solvent to the level of the nonane. Seal the vial and
label with the sample number. Store in the dark at room temperature
until ready for GC/MS analysis. If GC/MS analysis will not be performed
on the same day, store the vial at <-10 [deg]C.
13.0 Extract Cleanup
13.1 Cleanup may not be necessary for relatively clean samples
(e.g., treated effluents, groundwater, drinking water). If particular
circumstances require the use of a cleanup procedure, the analyst may
use any or all of the procedures below or any other appropriate
procedure. Before using a cleanup procedure, the analyst must
demonstrate that the requirements of Section 9.2 can be met using the
cleanup procedure. If only 2,3,7,8-TCDD and 2,3,7,8-TCDF are to be
determined, the cleanup procedures may be optimized for isolation of
these two compounds.
13.1.1 Gel permeation chromatography (Section 13.2) removes high
molecular weight interferences that cause GC column performance to
degrade. It should be used for all soil and sediment extracts and may be
used for water extracts that are expected to contain high molecular
weight organic compounds (e.g., polymeric materials, humic acids).
13.1.2 Acid, neutral, and basic silica gel (Section 13.3), alumina
(Section 13.4), and Florisil (Section 13.8) are used to remove nonpolar
and polar interferences. Alumina and Florisil are used to remove
chlorodiphenyl ethers.
13.1.3 Carbopak/Celite (Section 13.5) is used to remove nonpolar
interferences.
13.1.4 HPLC (Section 13.6) is used to provide specificity for the
2,3,7,8-substituted and other CDD and CDF isomers.
13.1.5 The anthropogenic isolation column (Section 13.7.1),
acidified silica gel batch adsorption procedure (Section 13.7.2), and
sulfuric acid and base back-extraction (Section 13.7.3) are used for
removal of lipids from tissue samples.
13.2 Gel Permeation Chromatography (GPC).
13.2.1 Column packing.
13.2.1.1 Place 70-75 g of SX-3 Bio-beads (Section 6.7.1.1) in a 400-
500 mL beaker.
13.2.1.2 Cover the beads with methylene chloride and allow to swell
overnight (a minimum of 12 hours).
13.2.1.3 Transfer the swelled beads to the column (Section 6.7.1.1)
and pump solvent through the column, from bottom to top, at 4.5-5.5 mL/
minute prior to connecting the column to the detector.
13.2.1.4 After purging the column with solvent for one to two hours,
adjust the column head pressure to 7-10 psig and purge for four to five
hours to remove air. Maintain a head pressure of 7-10 psig. Connect the
column to the detector (Section 6.7.1.4).
13.2.2 Column calibration.
13.2.2.1 Load 5 mL of the calibration solution (Section 7.4) into
the sample loop.
13.2.2.2 Inject the calibration solution and record the signal from
the detector. The elution pattern will be corn oil, bis(2-ethyl
hexyl)phthalate, pentachlorophenol, perylene, and sulfur.
13.2.2.3 Set the ``dump time'' to allow 85% removal of
the corn oil and 85% collection of the phthalate.
13.2.2.4 Set the ``collect time'' to the peak minimum between
perylene and sulfur.
13.2.2.5 Verify the calibration with the calibration solution after
every 20 extracts. Calibration is verified if the recovery of the
pentachlorophenol is greater than 85%. If calibration is not verified,
the system shall be recalibrated using the calibration solution, and the
previous 20 samples shall be re-extracted and cleaned up using the
calibrated GPC system.
13.2.3 Extract cleanup--GPC requires that the column not be
overloaded. The column specified in this method is designed to handle a
maximum of 0.5 g of high molecular weight material in a 5 mL extract. If
the extract is known or expected to contain more than 0.5 g, the extract
is split into aliquots for GPC, and the aliquots are combined after
elution from the column. The residue content of the extract may be
obtained gravimetrically by evaporating the solvent from a 50 [micro]L
aliquot.
13.2.3.1 Filter the extract or load through the filter holder
(Section 6.7.1.3) to remove the particles. Load the 5.0 mL extract onto
the column.
13.2.3.2 Elute the extract using the calibration data determined in
Section 13.2.2. Collect the eluate in a clean 400-500 mL beaker.
13.2.3.3 Rinse the sample loading tube thoroughly with methylene
chloride between extracts to prepare for the next sample.
13.2.3.4 If a particularly dirty extract is encountered, a 5.0 mL
methylene chloride blank shall be run through the system to check for
carry-over.
13.2.3.5 Concentrate the eluate per Sections 12.6 and 12.7 for
further cleanup or injection into the GC/MS.
13.3 Silica Gel Cleanup.
13.3.1 Place a glass-wool plug in a 15 mm ID chromatography column
(Section 6.7.4.2). Pack the column bottom to top with: 1 g silica gel
(Section 7.5.1.1), 4 g basic silica gel (Section 7.5.1.3), 1 g silica
gel, 8 g acid silica
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gel (Section 7.5.1.2), 2 g silica gel, and 4 g granular anhydrous sodium
sulfate (Section 7.2.1). Tap the column to settle the adsorbents.
13.3.2 Pre-elute the column with 50-100 mL of hexane. Close the
stopcock when the hexane is within 1 mm of the sodium sulfate. Discard
the eluate. Check the column for channeling. If channeling is present,
discard the column and prepare another.
13.3.3 Apply the concentrated extract to the column. Open the
stopcock until the extract is within 1 mm of the sodium sulfate.
13.3.4 Rinse the receiver twice with 1 mL portions of hexane, and
apply separately to the column. Elute the CDDs/CDFs with 100 mL hexane,
and collect the eluate.
13.3.5 Concentrate the eluate per Sections 12.6 and 12.7 for further
cleanup or injection into the HPLC or GC/MS.
13.3.6 For extracts of samples known to contain large quantities of
other organic compounds (such as paper mill effluents), it may be
advisable to increase the capacity of the silica gel column. This may be
accomplished by increasing the strengths of the acid and basic silica
gels. The acid silica gel (Section 7.5.1.2) may be increased in strength
to as much as 44% w/w (7.9 g sulfuric acid added to 10 g silica gel).
The basic silica gel (Section 7.5.1.3) may be increased in strength to
as much as 33% w/w (50 mL 1N NaOH added to 100 g silica gel), or the
potassium silicate (Section 7.5.1.4) may be used.
Note: The use of stronger acid silica gel (44% w/w) may lead to
charring of organic compounds in some extracts. The charred material may
retain some of the analytes and lead to lower recoveries of CDDs/CDFs.
Increasing the strengths of the acid and basic silica gel may also
require different volumes of hexane than those specified above to elute
the analytes off the column. Therefore, the performance of the method
after such modifications must be verified by the procedure in Section
9.2.
13.4 Alumina Cleanup.
13.4.1 Place a glass-wool plug in a 15 mm ID chromatography column
(Section 6.7.4.2).
13.4.2 If using acid alumina, pack the column by adding 6 g acid
alumina (Section 7.5.2.1). If using basic alumina, substitute 6 g basic
alumina (Section 7.5.2.2). Tap the column to settle the adsorbents.
13.4.3 Pre-elute the column with 50-100 mL of hexane. Close the
stopcock when the hexane is within 1 mm of the alumina.
13.4.4 Discard the eluate. Check the column for channeling. If
channeling is present, discard the column and prepare another.
13.4.5 Apply the concentrated extract to the column. Open the
stopcock until the extract is within 1 mm of the alumina.
13.4.6 Rinse the receiver twice with 1 mL portions of hexane and
apply separately to the column. Elute the interfering compounds with 100
mL hexane and discard the eluate.
13.4.7 The choice of eluting solvents will depend on the choice of
alumina (acid or basic) made in Section 13.4.2.
13.4.7.1 If using acid alumina, elute the CDDs/CDFs from the column
with 20 mL methylene chloride:hexane (20:80 v/v). Collect the eluate.
13.4.7.2 If using basic alumina, elute the CDDs/CDFs from the column
with 20 mL methylene chloride:hexane (50:50 v/v). Collect the eluate.
13.4.8 Concentrate the eluate per Sections 12.6 and 12.7 for further
cleanup or injection into the HPLC or GC/MS.
13.5 Carbon Column.
13.5.1 Cut both ends from a 10 mL disposable serological pipet
(Section 6.7.3.2) to produce a 10 cm column. Fire-polish both ends and
flare both ends if desired. Insert a glass-wool plug at one end, and
pack the column with 0.55 g of Carbopak/Celite (Section 7.5.3.3) to form
an adsorbent bed approximately 2 cm long. Insert a glass-wool plug on
top of the bed to hold the adsorbent in place.
13.5.2 Pre-elute the column with 5 mL of toluene followed by 2 mL of
methylene chloride: methanol:toluene (15:4:1 v/v), 1 mL of methylene
chloride:cyclohexane (1:1 v/v), and 5 mL of hexane. If the flow rate of
eluate exceeds 0.5 mL/minute, discard the column.
13.5.3 When the solvent is within 1 mm of the column packing, apply
the sample extract to the column. Rinse the sample container twice with
1 mL portions of hexane and apply separately to the column. Apply 2 mL
of hexane to complete the transfer.
13.5.4 Elute the interfering compounds with two 3 mL portions of
hexane, 2 mL of methylene chloride:cyclohexane (1:1 v/v), and 2 mL of
methylene chloride:methanol:toluene (15:4:1 v/v). Discard the eluate.
13.5.5 Invert the column, and elute the CDDs/CDFs with 20 mL of
toluene. If carbon particles are present in the eluate, filter through
glass-fiber filter paper.
13.5.6 Concentrate the eluate per Sections 12.6 and 12.7 for further
cleanup or injection into the HPLC or GC/MS.
13.6 HPLC (Reference 6).
13.6.1 Column calibration.
13.6.1.1 Prepare a calibration standard containing the 2,3,7,8-
substituted isomers and/or other isomers of interest at a concentration
of approximately 500 pg/[micro]L in methylene chloride.
13.6.1.2 Inject 30 [micro]L of the calibration solution into the
HPLC and record the signal from the detector. Collect the eluant for
reuse. The elution order will be the tetra- through octa-isomers.
13.6.1.3 Establish the collection time for the tetra-isomers and for
the other isomers of interest. Following calibration, flush the
injection system with copious quantities of
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methylene chloride, including a minimum of five 50 [micro]L injections
while the detector is monitored, to ensure that residual CDDs/CDFs are
removed from the system.
13.6.1.4 Verify the calibration with the calibration solution after
every 20 extracts. Calibration is verified if the recovery of the CDDs/
CDFs from the calibration standard (Section 13.6.1.1) is 75-125%
compared to the calibration (Section 13.6.1.2). If calibration is not
verified, the system shall be recalibrated using the calibration
solution, and the previous 20 samples shall be re-extracted and cleaned
up using the calibrated system.
13.6.2 Extract cleanup--HPLC requires that the column not be
overloaded. The column specified in this method is designed to handle a
maximum of 30 [micro]L of extract. If the extract cannot be concentrated
to less than 30 [micro]L, it is split into fractions and the fractions
are combined after elution from the column.
13.6.2.1 Rinse the sides of the vial twice with 30 [micro]L of
methylene chloride and reduce to 30 [micro]L with the evaporation
apparatus (Section 12.7).
13.6.2.2 Inject the 30 [micro]L extract into the HPLC.
13.6.2.3 Elute the extract using the calibration data determined in
Section 13.6.1. Collect the fraction(s) in a clean 20 mL concentrator
tube containing 5 mL of hexane:acetone (1:1 v/v).
13.6.2.4 If an extract containing greater than 100 ng/mL of total
CDD or CDF is encountered, a 30 [micro]L methylene chloride blank shall
be run through the system to check for carry-over.
13.6.2.5 Concentrate the eluate per Section 12.7 for injection into
the GC/MS.
13.7 Cleanup of Tissue Lipids--Lipids are removed from the Soxhlet
extract using either the anthropogenic isolation column (Section 13.7.1)
or acidified silica gel (Section 13.7.2), or are removed from the HCl
digested extract using sulfuric acid and base back-extraction (Section
13.7.3).
13.7.1 Anthropogenic isolation column (References 22 and 27)--Used
for removal of lipids from the Soxhlet/SDS extraction (Section 12.4.1).
13.7.1.1 Prepare the column as given in Section 7.5.4.
13.7.1.2 Pre-elute the column with 100 mL of hexane. Drain the
hexane layer to the top of the column, but do not expose the sodium
sulfate.
13.7.1.3 Load the sample and rinses (Section 12.4.1.9.2) onto the
column by draining each portion to the top of the bed. Elute the CDDs/
CDFs from the column into the apparatus used for concentration (Section
12.4.1.7) using 200 mL of hexane.
13.7.1.4 Concentrate the cleaned up extract (Sections 12.6 through
12.7) to constant weight per Section 12.7.3.1. If more than 500 mg of
material remains, repeat the cleanup using a fresh anthropogenic
isolation column.
13.7.1.5 Redissolve the extract in a solvent suitable for the
additional cleanups to be used (Sections 13.2 through 13.6 and 13.8).
13.7.1.6 Spike 1.0 mL of the cleanup standard (Section 7.11) into
the residue/solvent.
13.7.1.7 Clean up the extract using the procedures in Sections 13.2
through 13.6 and 13.8. Alumina (Section 13.4) or Florisil (Section 13.8)
and carbon (Section 13.5) are recommended as minimum additional cleanup
steps.
13.7.1.8 Following cleanup, concentrate the extract to 10 [micro]L
as described in Section 12.7 and proceed with the analysis in Section
14.
13.7.2 Acidified silica gel (Reference 28)--Procedure alternate to
the anthropogenic isolation column (Section 13.7.1) that is used for
removal of lipids from the Soxhlet/SDS extraction (Section 12.4.1).
13.7.2.1 Adjust the volume of hexane in the bottle (Section
12.4.1.9.2) to approximately 200 mL.
13.7.2.2 Spike 1.0 mL of the cleanup standard (Section 7.11) into
the residue/solvent.
13.7.2.3 Drop the stirring bar into the bottle, place the bottle on
the stirring plate, and begin stirring.
13.7.2.4 Add 30-100 g of acid silica gel (Section 7.5.1.2) to the
bottle while stirring, keeping the silica gel in motion. Stir for two to
three hours.
Note: 30 grams of silica gel should be adequate for most samples and
will minimize contamination from this source.
13.7.2.5 After stirring, pour the extract through approximately 10 g
of granular anhydrous sodium sulfate (Section 7.2.1) contained in a
funnel with glass-fiber filter into a macro contration device (Section
12.6). Rinse the bottle and sodium sulfate with hexane to complete the
transfer.
13.7.2.6 Concentrate the extract per Sections 12.6 through 12.7 and
clean up the extract using the procedures in Sections 13.2 through 13.6
and 13.8. Alumina (Section 13.4) or Florisil (Section 13.8) and carbon
(Section 13.5) are recommended as minimum additional cleanup steps.
13.7.3 Sulfuric acid and base back-extraction. Used with HCl
digested extracts (Section 12.4.2).
13.7.3.1 Spike 1.0 mL of the cleanup standard (Section 7.11) into
the residue/solvent (Section 12.4.2.8.2).
13.7.3.2 Add 10 mL of concentrated sulfuric acid to the bottle.
Immediately cap and shake one to three times. Loosen cap in a hood to
vent excess pressure. Cap and shake the bottle so that the residue/
solvent is exposed to the acid for a total time of approximately 45
seconds.
13.7.3.3 Decant the hexane into a 250 mL separatory funnel making
sure that no acid
[[Page 328]]
is transferred. Complete the quantitative transfer with several hexane
rinses.
13.7.3.4 Back extract the solvent/residue with 50 mL of potassium
hydroxide solution per Section 12.5.2, followed by two reagent water
rinses.
13.7.3.5 Drain the extract through a filter funnel containing
approximately 10 g of granular anhydrous sodium sulfate in a glass-fiber
filter into a macro concentration device (Section 12.6).
13.7.3.6 Concentrate the cleaned up extract to a volume suitable for
the additional cleanups given in Sections 13.2 through 13.6 and 13.8.
Gel permeation chromatography (Section 13.2), alumina (Section 13.4) or
Florisil (Section 13.8), and Carbopak/Celite (Section 13.5) are
recommended as minimum additional cleanup steps.
13.7.3.7 Following cleanup, concentrate the extract to 10 L as
described in Section 12.7 and proceed with analysis per Section 14.
13.8 Florisil Cleanup (Reference 29).
13.8.1 Pre-elute the activated Florisil column (Section 7.5.3) with
10 mL of methylene chloride followed by 10 mL of hexane:methylene
chloride (98:2 v/v) and discard the solvents.
13.8.2 When the solvent is within 1 mm of the packing, apply the
sample extract (in hexane) to the column. Rinse the sample container
twice with 1 mL portions of hexane and apply to the column.
13.8.3 Elute the interfering compounds with 20 mL of
hexane:methylene chloride (98:2) and discard the eluate.
13.8.4 Elute the CDDs/CDFs with 35 mL of methylene chloride and
collect the eluate. Concentrate the eluate per Sections 12.6 through
12.7 for further cleanup or for injection into the HPLC or GC/MS.
14.0 HRGC/HRMS Analysis
14.1 Establish the operating conditions given in Section 10.1.
14.2 Add 10 uL of the appropriate internal standard solution
(Section 7.12) to the sample extract immediately prior to injection to
minimize the possibility of loss by evaporation, adsorption, or
reaction. If an extract is to be reanalyzed and evaporation has
occurred, do not add more instrument internal standard solution. Rather,
bring the extract back to its previous volume (e.g., 19 L) with pure
nonane only (18 L if 2 L injections are used).
14.3 Inject 1.0 [micro]L or 2.0 [micro]L of the concentrated extract
containing the internal standard solution, using on-column or splitless
injection. The volume injected must be identical to the volume used for
calibration (Section 10). Start the GC column initial isothermal hold
upon injection. Start MS data collection after the solvent peak elutes.
Stop data collection after the OCDD and OCDF have eluted. If only
2,3,7,8-TCDD and 2,3,7,8-TCDF are to be determined, stop data collection
after elution of these compounds. Return the column to the initial
temperature for analysis of the next extract or standard.
15.0 System and Laboratory Performance
15.1 At the beginning of each 12-hour shift during which analyses
are performed, GC/MS system performance and calibration are verified for
all CDDs/CDFs and labeled compounds. For these tests, analysis of the
CS3 calibration verification (VER) standard (Section 7.13 and Table 4)
and the isomer specificity test standards (Section 7.15 and Table 5)
shall be used to verify all performance criteria. Adjustment and/or
recalibration (Section 10) shall be performed until all performance
criteria are met. Only after all performance criteria are met may
samples, blanks, IPRs, and OPRs be analyzed.
15.2 MS Resolution--A static resolving power of at least 10,000 (10%
valley definition) must be demonstrated at the appropriate m/z before
any analysis is performed. Static resolving power checks must be
performed at the beginning and at the end of each 12-hour shift
according to procedures in Section 10.1.2. Corrective actions must be
implemented whenever the resolving power does not meet the requirement.
15.3 Calibration Verification.
15.3.1 Inject the VER standard using the procedure in Section 14.
15.3.2 The m/z abundance ratios for all CDDs/CDFs shall be within
the limits in Table 9; otherwise, the mass spectrometer shall be
adjusted until the m/z abundance ratios fall within the limits
specified, and the verification test shall be repeated. If the
adjustment alters the resolution of the mass spectrometer, resolution
shall be verified (Section 10.1.2) prior to repeat of the verification
test.
15.3.3 The peaks representing each CDD/CDF and labeled compound in
the VER standard must be present with S/N of at least 10; otherwise, the
mass spectrometer shall be adjusted and the verification test repeated.
15.3.4 Compute the concentration of each CDD/CDF compound by isotope
dilution (Section 10.5) for those compounds that have labeled analogs
(Table 1). Compute the concentration of the labeled compounds by the
internal standard method (Section 10.6). These concentrations are
computed based on the calibration data in Section 10.
15.3.5 For each compound, compare the concentration with the
calibration verification limit in Table 6. If only 2,3,7,8-TCDD and
2,3,7,8-TCDF are to be determined, compare the concentration to the
limit in Table 6a. If all compounds meet the acceptance criteria,
calibration has been verified and analysis of standards and sample
extracts may proceed. If, however, any compound fails its respective
limit, the measurement system is not performing properly for
[[Page 329]]
that compound. In this event, prepare a fresh calibration standard or
correct the problem causing the failure and repeat the resolution
(Section 15.2) and verification (Section 15.3) tests, or recalibrate
(Section 10).
15.4 Retention Times and GC Resolution.
15.4.1 Retention times.
15.4.1.1 Absolute--The absolute retention times of the
\13\C12-1,2,3,4-TCDD and \13\C12-1,2,3,7,8,9-HxCDD
GCMS internal standards in the verification test (Section 15.3) shall be
within 15 seconds of the retention times obtained
during calibration (Sections 10.2.1 and 10.2.4).
15.4.1.2 Relative--The relative retention times of CDDs/CDFs and
labeled compounds in the verification test (Section 15.3) shall be
within the limits given in Table 2.
15.4.2 GC resolution.
15.4.2.1 Inject the isomer specificity standards (Section 7.15) on
their respective columns.
15.4.2.2 The valley height between 2,3,7,8-TCDD and the other tetra-
dioxin isomers at m/z 319.8965, and between 2,3,7,8-TCDF and the other
tetra-furan isomers at m/z 303.9016 shall not exceed 25% on their
respective columns (Figures 6 and 7).
15.4.3 If the absolute retention time of any compound is not within
the limits specified or if the 2,3,7,8-isomers are not resolved, the GC
is not performing properly. In this event, adjust the GC and repeat the
verification test (Section 15.3) or recalibrate (Section 10), or replace
the GC column and either verify calibration or recalibrate.
15.5 Ongoing Precision and Recovery.
15.5.1 Analyze the extract of the ongoing precision and recovery
(OPR) aliquot (Section 11.4.2.5, 11.5.4, 11.6.2, 11.7.4, or 11.8.3.2)
prior to analysis of samples from the same batch.
15.5.2 Compute the concentration of each CDD/CDF by isotope dilution
for those compounds that have labeled analogs (Section 10.5). Compute
the concentration of 1,2,3,7,8,9-HxCDD, OCDF, and each labeled compound
by the internal standard method (Section 10.6).
15.5.3 For each CDD/CDF and labeled compound, compare the
concentration to the OPR limits given in Table 6. If only 2,3,7,8-TCDD
and 2,3,7,8-TCDF are to be determined, compare the concentration to the
limits in Table 6a. If all compounds meet the acceptance criteria,
system performance is acceptable and analysis of blanks and samples may
proceed. If, however, any individual concentration falls outside of the
range given, the extraction/concentration processes are not being
performed properly for that compound. In this event, correct the
problem, re-prepare, extract, and clean up the sample batch and repeat
the ongoing precision and recovery test (Section 15.5).
15.5.4 Add results that pass the specifications in Section 15.5.3 to
initial and previous ongoing data for each compound in each matrix.
Update QC charts to form a graphic representation of continued
laboratory performance. Develop a statement of laboratory accuracy for
each CDD/CDF in each matrix type by calculating the average percent
recovery (R) and the standard deviation of percent recovery
(SR). Express the accuracy as a recovery interval from R-
2SR to R = 2SR. For example, if R = 95% and
SR = 5%, the accuracy is 85-105%.
15.6 Blank--Analyze the method blank extracted with each sample
batch immediately following analysis of the OPR aliquot to demonstrate
freedom from contamination and freedom from carryover from the OPR
analysis. The results of the analysis of the blank must meet the
specifications in Section 9.5.2 before sample analyses may proceed.
16.0 Qualitative Determination
A CDD, CDF, or labeled compound is identified in a standard, blank,
or sample when all of the criteria in Sections 16.1 through 16.4 are
met.
16.1 The signals for the two exact m/z's in Table 8 must be present
and must maximize within the same two seconds.
16.2 The signal-to-noise ratio (S/N) for the GC peak at each exact
m/z must be greater than or equal to 2.5 for each CDD or CDF detected in
a sample extract, and greater than or equal to 10 for all CDDs/CDFs in
the calibration standard (Sections 10.2.3 and 15.3.3).
16.3 The ratio of the integrated areas of the two exact m/z's
specified in Table 8 must be within the limit in Table 9, or within
10% of the ratio in the midpoint (CS3) calibration
or calibration verification (VER), whichever is most recent.
16.4 The relative retention time of the peak for a 2,3,7,8-
substituted CDD or CDF must be within the limit in Table 2. The
retention time of peaks representing non-2,3,7,8-substituted CDDs/CDFs
must be within the retention time windows established in Section 10.3.
16.5 Confirmatory Analysis--Isomer specificity for 2,3,7,8-TCDF
cannot be achieved on the DB-5 column. Therefore, any sample in which
2,3,7,8-TCDF is identified by analysis on a DB-5 column must have a
confirmatory analysis performed on a DB-225, SP-2330, or equivalent GC
column. The operating conditions in Section 10.1.1 may be adjusted to
optimize the analysis on the second GC column, but the GC/MS must meet
the mass resolution and calibration specifications in Section 10.
16.6 If the criteria for identification in Sections 16.1 through
16.5 are not met, the CDD or CDF has not been identified and the results
may not be reported for regulatory compliance purposes. If interferences
preclude identification, a new aliquot of sample
[[Page 330]]
must be extracted, further cleaned up, and analyzed.
17.0 Quantitative Determination
17.1 Isotope Dilution Quantitation--By adding a known amount of a
labeled compound to every sample prior to extraction, correction for
recovery of the CDD/CDF can be made because the CDD/CDF and its labeled
analog exhibit similar effects upon extraction, concentration, and gas
chromatography. Relative response (RR) values are used in conjunction
with the initial calibration data described in Section 10.5 to determine
concentrations directly, so long as labeled compound spiking levels are
constant, using the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE97.007
where:
Cex = The concentration of the CDD/CDF in the extract, and
the other terms are as defined in Section 10.5.2.
17.1.1 Because of a potential interference, the labeled analog of
OCDF is not added to the sample. Therefore, OCDF is quantitated against
labeled OCDD. As a result, the concentration of OCDF is corrected for
the recovery of the labeled OCDD. In instances where OCDD and OCDF
behave differently during sample extraction, concentration, and cleanup
procedures, this may decrease the accuracy of the OCDF results. However,
given the low toxicity of this compound relative to the other dioxins
and furans, the potential decrease in accuracy is not considered
significant.
17.1.2 Because \13\C12-1,2,3,7,8,9-HxCDD is used as an
instrument internal standard (i.e., not added before extraction of the
sample), it cannot be used to quantitate the 1,2,3,7,8,9-HxCDD by strict
isotope dilution procedures. Therefore, 1,2,3,7,8,9-HxCDD is quantitated
using the averaged response of the labeled analogs of the other two
2,3,7,8-substituted HxCDD's: 1,2,3,4,7,8-HxCDD and 1,2,3,6,7,8-HxCDD. As
a result, the concentration of 1,2,3,7,8,9-HxCDD is corrected for the
average recovery of the other two HxCDD's.
17.1.3 Any peaks representing non-2,3,7,8-substituted CDDs/CDFs are
quantitated using an average of the response factors from all of the
labeled 2,3,7,8-isomers at the same level of chlorination.
17.2 Internal Standard Quantitation and Labeled Compound Recovery.
17.2.1 Compute the concentrations of 1,2,3,7,8,9-HxCDD, OCDF, the
\13\C-labeled analogs and the \37\C-labeled cleanup standard in the
extract using the response factors determined from the initial
calibration data (Section 10.6) and the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE97.008
where:
Cex = The concentration of the CDD/CDF in the extract, and
the other terms are as defined in Section 10.6.1.
Note: There is only one m/z for the \37\Cl-labeled standard.
17.2.2 Using the concentration in the extract determined above,
compute the percent recovery of the \13\C-labeled compounds and the
\37\C-labeled cleanup standard using the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE97.009
17.3 The concentration of a CDD/CDF in the solid phase of the sample
is computed using the concentration of the compound in the extract and
the weight of the solids (Section 11.5.1), as follows:
[GRAPHIC] [TIFF OMITTED] TR15SE97.010
where:
Cex = The concentration of the compound in the extract.
Vex = The extract volume in mL.
Ws = The sample weight (dry weight) in kg.
17.4 The concentration of a CDD/CDF in the aqueous phase of the
sample is computed using the concentration of the compound in
[[Page 331]]
the extract and the volume of water extracted (Section 11.4 or 11.5), as
follows:
[GRAPHIC] [TIFF OMITTED] TR15SE97.011
where:
Cex = The concentration of the compound in the extract.
Vex = The extract volume in mL.
Vs = The sample volume in liters.
17.5 If the SICP area at either quantitation m/z for any compound
exceeds the calibration range of the system, a smaller sample aliquot is
extracted.
17.5.1 For aqueous samples containing 1% solids or less, dilute 100
mL, 10 mL, etc., of sample to 1 L with reagent water and re-prepare,
extract, clean up, and analyze per Sections 11 through 14.
17.5.2 For samples containing greater than 1% solids, extract an
amount of sample equal to \1/10\, \1/100\, etc., of the amount used in
Section 11.5.1. Re-prepare, extract, clean up, and analyze per Sections
11 through 14.
17.5.3 If a smaller sample size will not be representative of the
entire sample, dilute the sample extract by a factor of 10, adjust the
concentration of the instrument internal standard to 100 pg/[micro]L in
the extract, and analyze an aliquot of this diluted extract by the
internal standard method.
17.6 Results are reported to three significant figures for the CDDs/
CDFs and labeled compounds found in all standards, blanks, and samples.
17.6.1 Reporting units and levels.
17.6.1.1 Aqueous samples--Report results in pg/L (parts-per-
quadrillion).
17.6.1.2 Samples containing greater than 1% solids (soils,
sediments, filter cake, compost)--Report results in ng/kg based on the
dry weight of the sample. Report the percent solids so that the result
may be corrected.
17.6.1.3 Tissues--Report results in ng/kg of wet tissue, not on the
basis of the lipid content of the sample. Report the percent lipid
content, so that the data user can calculate the concentration on a
lipid basis if desired.
17.6.1.4 Reporting level.
17.6.1.4.1 Standards (VER, IPR, OPR) and samples--Report results at
or above the minimum level (Table 2). Report results below the minimum
level as not detected or as required by the regulatory authority.
17.6.1.4.2 Blanks--Report results above one-third the ML.
17.6.2 Results for CDDs/CDFs in samples that have been diluted are
reported at the least dilute level at which the areas at the
quantitation m/z's are within the calibration range (Section 17.5).
17.6.3 For CDDs/CDFs having a labeled analog, results are reported
at the least dilute level at which the area at the quantitation m/z is
within the calibration range (Section 17.5) and the labeled compound
recovery is within the normal range for the method (Section 9.3 and
Tables 6, 6a, 7, and 7a).
17.6.4 Additionally, if requested, the total concentration of all
isomers in an individual level of chlorination (i.e., total TCDD, total
TCDF, total Paced, etc.) may be reported by summing the concentrations
of all isomers identified in that level of chlorination, including both
2,3,7,8-substituted and non-2,3,7,8-substituted isomers.
18.0 Analysis of Complex Samples
18.1 Some samples may contain high levels (10 ng/L;
1000 ng/kg) of the compounds of interest, interfering
compounds, and/or polymeric materials. Some extracts will not
concentrate to 10 [micro]L (Section 12.7); others may overload the GC
column and/or mass spectrometer.
18.2 Analyze a smaller aliquot of the sample (Section 17.5) when the
extract will not concentrate to 10 [micro]L after all cleanup procedures
have been exhausted.
18.3 Chlorodiphenyl Ethers--If chromatographic peaks are detected at
the retention time of any CDDs/CDFs in any of the m/z channels being
monitored for the chlorodiphenyl ethers (Table 8), cleanup procedures
must be employed until these interferences are removed. Alumina (Section
13.4) and Florisil (Section 13.8) are recommended for removal of
chlorodiphenyl ethers.
18.4 Recovery of Labeled Compounds--In most samples, recoveries of
the labeled compounds will be similar to those from reagent water or
from the alternate matrix (Section 7.6).
18.4.1 If the recovery of any of the labeled compounds is outside of
the normal range (Table 7), a diluted sample shall be analyzed (Section
17.5).
18.4.2 If the recovery of any of the labeled compounds in the
diluted sample is outside of normal range, the calibration verification
standard (Section 7.13) shall be analyzed and calibration verified
(Section 15.3).
[[Page 332]]
18.4.3 If the calibration cannot be verified, a new calibration must
be performed and the original sample extract reanalyzed.
18.4.4 If the calibration is verified and the diluted sample does
not meet the limits for labeled compound recovery, the method does not
apply to the sample being analyzed and the result may not be reported
for regulatory compliance purposes. In this case, alternate extraction
and cleanup procedures in this method must be employed to resolve the
interference. If all cleanup procedures in this method have been
employed and labeled compound recovery remains outside of the normal
range, extraction and/or cleanup procedures that are beyond this scope
of this method will be required to analyze these samples.
19.0 Pollution Prevention
19.1 The solvents used in this method pose little threat to the
environment when managed properly. The solvent evaporation techniques
used in this method are amenable to solvent recovery, and it is
recommended that the laboratory recover solvents wherever feasible.
19.2 Standards should be prepared in volumes consistent with
laboratory use to minimize disposal of standards.
20.0 Waste Management
20.1 It is the laboratory's responsibility to comply with all
federal, state, and local regulations governing waste management,
particularly the hazardous waste identification rules and land disposal
restrictions, and to protect the air, water, and land by minimizing and
controlling all releases from fume hoods and bench operations.
Compliance is also required with any sewage discharge permits and
regulations.
20.2 Samples containing HCl to pH <2 are hazardous and must be
neutralized before being poured down a drain or must be handled as
hazardous waste.
20.3 The CDDs/CDFs decompose above 800 [deg]C. Low-level waste such
as absorbent paper, tissues, animal remains, and plastic gloves may be
burned in an appropriate incinerator. Gross quantities (milligrams)
should be packaged securely and disposed of through commercial or
governmental channels that are capable of handling extremely toxic
wastes.
20.4 Liquid or soluble waste should be dissolved in methanol or
ethanol and irradiated with ultraviolet light with a wavelength shorter
than 290 nm for several days. Use F40 BL or equivalent lamps. Analyze
liquid wastes, and dispose of the solutions when the CDDs/CDFs can no
longer be detected.
20.5 For further information on waste management, consult ``The
Waste Management Manual for Laboratory Personnel'' and ``Less is
Better--Laboratory Chemical Management for Waste Reduction,'' available
from the American Chemical Society's Department of Government Relations
and Science Policy, 1155 16th Street N.W., Washington, D.C. 20036.
21.0 Method Performance
Method performance was validated and performance specifications were
developed using data from EPA's international interlaboratory validation
study (References 30-31) and the EPA/paper industry Long-Term
Variability Study of discharges from the pulp and paper industry (58 FR
66078).
22.0 References
1. Tondeur, Yves. ``Method 8290: Analytical Procedures and Quality
Assurance for Multimedia Analysis of Polychlorinated Dibenzo-p-dioxins
and Dibenzofurans by High Resolution Gas Chromatography/High Resolution
Mass Spectrometry,'' USEPA EMSL, Las Vegas, Nevada, June 1987.
2. ``Measurement of 2,3,7,8-Tetrachlorinated Dibenzo-p-dioxin (TCDD)
and 2,3,7,8-Tetrachlorinated Dibenzofuran (TCDF) in Pulp, Sludges,
Process Samples and Wastewaters from Pulp and Paper Mills,'' Wright
State University, Dayton, OH 45435, June 1988.
3. ``NCASI Procedures for the Preparation and Isomer Specific
Analysis of Pulp and Paper Industry Samples for 2,3,7,8-TCDD and
2,3,7,8-TCDF,'' National Council of the Paper Industry for Air and
Stream Improvement Inc., 260 Madison Avenue, New York, NY 10016,
Technical Bulletin No. 551, Pre-Release Copy, July 1988.
4. ``Analytical Procedures and Quality Assurance Plan for the
Determination of PCDD/PCDF in Fish,'' USEPA, Environmental Research
Laboratory, 6201 Congdon Boulevard, Duluth, MN 55804, April 1988.
5. Tondeur, Yves. ``Proposed GC/MS Methodology for the Analysis of
PCDDs and PCDFs in Special Analytical Services Samples,'' Triangle
Laboratories, Inc., 801-10 Capitola Dr, Research Triangle Park, NC
27713, January 1988; updated by personal communication September 1988.
6. Lamparski, L.L. and Nestrick, T.J. ``Determination of Tetra-,
Hexa-, Hepta-, and Octachlorodibenzo-p-dioxin Isomers in Particulate
Samples at Parts per Trillion Levels,'' Analytical Chemistry, 52: 2045-
2054, 1980.
7. Lamparski, L.L. and Nestrick, T.J. ``Novel Extraction Device for
the Determination of Chlorinated Dibenzo-p-dioxins (PCDDs) and
Dibenzofurans (PCDFs) in Matrices Containing Water,'' Chemosphere,
19:27-31, 1989.
8. Patterson, D.G., et. al. ``Control of Interferences in the
Analysis of Human Adipose Tissue for 2,3,7,8-Tetrachlorodibenzo-p-
[[Page 333]]
dioxin,'' Environmental Toxicological Chemistry, 5:355-360, 1986.
9. Stanley, John S. and Sack, Thomas M. ``Protocol for the Analysis
of 2,3,7,8-Tetrachlorodibenzo-p-dioxin by High Resolution Gas
Chromatography/High Resolution Mass Spectrometry,'' USEPA EMSL, Las
Vegas, Nevada 89114, EPA 600/4-86-004, January 1986.
10. ``Working with Carcinogens,'' Department of Health, Education, &
Welfare, Public Health Service, Centers for Disease Control, NIOSH,
Publication 77-206, August 1977, NTIS PB-277256.
11. ``OSHA Safety and Health Standards, General Industry,'' OSHA
2206, 29 CFR 1910.
12. ``Safety in Academic Chemistry Laboratories,'' ACS Committee on
Chemical Safety, 1979.
13. ``Standard Methods for the Examination of Water and
Wastewater,'' 18th edition and later revisions, American Public Health
Association, 1015 15th St, N.W., Washington, DC 20005, 1-35: Section
1090 (Safety), 1992.
14. ``Method 613--2,3,7,8-Tetrachlorodibenzo-p-dioxin,'' 40 CFR 136
(49 FR 43234), October 26, 1984, Section 4.1.
15. Provost, L.P. and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15: 56-83, 1983.
16. ``Standard Practice for Sampling Water,'' ASTM Annual Book of
Standards, ASTM, 1916 Race Street, Philadelphia, PA 19103-1187, 1980.
17. ``Methods 330.4 and 330.5 for Total Residual Chlorine,'' USEPA,
EMSL, Cincinnati, OH 45268, EPA 600/4-79-020, March 1979.
18. ``Handbook of Analytical Quality Control in Water and Wastewater
Laboratories,'' USEPA EMSL, Cincinnati, OH 45268, EPA-600/4-79-019,
March 1979.
19. Williams, Rick. Letter to Bill Telliard, June 4, 1993, available
from the EPA Sample Control Center operated by DynCorp Viar, Inc., 300 N
Lee St, Alexandria, VA 22314, 703-519-1140.
20. Barkowski, Sarah. Fax to Sue Price, August 6, 1992, available
from the EPA Sample Control Center operated by DynCorp Viar, Inc., 300 N
Lee St, Alexandria VA 22314, 703-519-1140.
21. ``Analysis of Multi-media, Multi-concentration Samples for
Dioxins and Furans, PCDD/PCDF Analyses Data Package'', Narrative for
Episode 4419, MRI Project No. 3091-A, op.cit. February 12, 1993,
Available from the EPA Sample Control Center operated by DynCorp Viar
Inc, 300 N Lee St, Alexandria, VA 22314 (703-519-1140).
22. ``Analytical Procedures and Quality Assurance Plan for the
Determination of PCDD/PCDF in Fish'', U.S. Environmental Protection
Agency, Environmental Research Laboratory, Duluth, MN 55804, EPA/600/3-
90/022, March 1990.
23. Afghan, B.K., Carron, J., Goulden, P.D., Lawrence, J., Leger,
D., Onuska, F., Sherry, J., and Wilkenson, R.J., ``Recent Advances in
Ultratrace Analysis of Dioxins and Related Halogenated Hydrocarbons'',
Can J. Chem., 65: 1086-1097, 1987.
24. Sherry, J.P. and Tse, H. ``A Procedure for the Determination of
Polychlorinated Dibenzo-p-dioxins in Fish'', Chemosphere, 20: 865-872,
1990.
25. ``Preliminary Fish Tissue Study'', Results of Episode 4419,
available from the EPA Sample Control Center operated by DynCorp Viar,
Inc., 300 N Lee St, Alexandria, VA 22314, 703-519-1140.
26. Nestrick, Terry L. DOW Chemical Co., personal communication with
D.R. Rushneck, April 8, 1993. Details available from the U.S.
Environmental Protection Agency Sample Control Center operated by
DynCorp Viar Inc, 300 N Lee St, Alexandria, VA 22314, 703-519-1140.
27. Barnstadt, Michael. ``Big Fish Column'', Triangle Laboratories
of RTP, Inc., SOP 129-90, 27 March 27, 1992.
28. ``Determination of Polychlorinated Dibenzo-p-Dioxins (PCDD) and
Dibenzofurans (PCDF) in Environmental Samples Using EPA Method 1613'',
Chemical Sciences Department, Midwest Research Institute, 425 Volker
Boulevard, Kansas City, MO 44110-2299, Standard Operating Procedure No.
CS-153, January 15, 1992.
29. Ryan, John J. Raymonde Lizotte and William H. Newsome, J.
Chromatog. 303 (1984) 351-360.
30. Telliard, William A., McCarty, Harry B., and Riddick, Lynn S.
``Results of the Interlaboratory Validation Study of USEPA Method 1613
for the Analysis of Tetra-through Octachlorinated Dioxins and Furans by
Isotope Dilution GC/MS,'' Chemosphere, 27, 41-46 (1993).
31. ``Results of the International Interlaboratory Validation Study
of USEPA Method 1613'', October 1994, available from the EPA Sample
Control Center operated by DynCorp Viar, Inc., 300 N Lee St, Alexandria,
VA 22314, 703-519-1140.
23.0 Tables and Figures
[[Page 334]]
Table 1--Chlorinated Dibenzo-p-Dioxins and Furans Determined by Isotope Dilution and Internal Standard High
Resolution Gas Chromatography (HRGC)/High Resolution Mass Spectrometry (HRMS)
----------------------------------------------------------------------------------------------------------------
CDDs/CDFs \1\ CAS registry Labeled analog CAS registry
----------------------------------------------------------------------------------------------------------------
2,3,7,8-TCDD.................................. 1746-01-6 \13\C12-2,3,7,8-TCDD............ 76523-40-5
\37\Cl4-2,3,7,8-TCDD............ 85508-50-5
Total TCDD.................................... 41903-57-5
2,3,7,8-TCDF.................................. 51207-31-9 \13\C12-2,3,7,8-TCDF............ 89059-46-1
Total-TCDF.................................... 55722-27-5
1,2,3,7,8-PeCDD............................... 40321-76-4 \13\C12-1,2,3,7,8-PeCDD......... 109719-79-1
Total-PeCDD................................... 36088-22-9
1,2,3,7,8-PeCDF............................... 57117-41-6 \13\C12-1,2,3,7,8-PeCDF......... 109719-77-9
2,3,4,7,8-PeCDF............................... 57117-31-4 \13\C12-2,3,4,7,8-PeCDF......... 116843-02-8
Total-PeCDF................................... 30402-15-4
1,2,3,4,7,8-HxCDD............................. 39227-28-6 \13\C12-1,2,3,4,7,8-HxCDD....... 109719-80-4
1,2,3,6,7,8-HxCDD............................. 57653-85-7 \13\C12-1,2,3,6,7,8-HxCDD....... 109719-81-5
1,2,3,7,8,9-HxCDD............................. 19408-74-3 \13\C12-1,2,3,7,8,9-HxCDD....... 109719-82-6
Total-HxCDD................................... 34465-46-8
1,2,3,4,7,8-HxCDF............................. 70648-26-9 \13\C12-1,2,3,4,7,8-HxCDF....... 114423-98-2
1,2,3,6,7,8-HxCDF............................. 57117-44-9 \13\C12-1,2,3,6,7,8-HxCDF....... 116843-03-9
1,2,3,7,8,9-HxCDF............................. 72918-21-9 \13\C12-1,2,3,7,8,9-HxCDF....... 116843-04-0
2,3,4,6,7,8-HxCDF............................. 60851-34-5 \13\C12-2,3,4,6,7,8-HxCDF....... 116843-05-1
Total-HxCDF................................... 55684-94-1
1,2,3,4,6,7,8-HpCDD........................... 35822-46-9 \13\C12-1,2,3,4,6,7,8-HpCDD..... 109719-83-7
Total-HpCDD................................... 37871-00-4
1,2,3,4,6,7,8-HpCDF........................... 67562-39-4 \13\C12-1,2,3,4,6,7,8-HpCDF..... 109719-84-8
1,2,3,4,7,8,9-HpCDF........................... 55673-89-7 \13\C12-1,2,3,4,7,8,9-HpCDF..... 109719-94-0
Total-HpCDF................................... 38998-75-3
OCDD.......................................... 3268-87-9 \13\C12-OCDD.................... 114423-97-1
OCDF.......................................... 39001-02-0 Not used........................
----------------------------------------------------------------------------------------------------------------
\1\ Chlorinated dibenzo-p-dioxins and chlorinated dibenzofurans.
TCDD = Tetrachlorodibenzo-p-dioxin.
TCDF = Tetrachlorodibenzofuran.
PeCDD = Pentachlorodibenzo-p-dioxin.
PeCDF = Pentachlorodibenzofuran.
HxCDD = Hexachlorodibenzo-p-dioxin.
HxCDF = Hexachlorodibenzofuran.
HpCDD = Heptachlorodibenzo-p-dioxin.
HpCDF = Heptachlorodibenzofuran.
OCDD = Octachlorodibenzo-p-dioxin.
OCDF = Octachlorodibenzofuran.
Table 2--Retention Time References, Quantitation References, Relative Retention Times, and Minimum Levels for
CDDS and DCFS
----------------------------------------------------------------------------------------------------------------
Minimum level \1\
--------------------------------
Retention time and Relative Extract
CDD/CDF quantitation reference retention time Water (pg/ Solid (ng/ (pg/
L; ppq) kg; ppt) [micro]L;
ppb)
----------------------------------------------------------------------------------------------------------------
Compounds using \13\ C12-1,2,3,4-TCDD as the Injection Internal Standard
----------------------------------------------------------------------------------------------------------------
2,3,7,8-TCDF......................... \13\ C12-2,3,7,8-TCDF... 0.999-1.003 10 1 0.5
2,3,7,8-TCDD......................... \13\ C12-2,3,7,8-TCDD... 0.999-1.002 10 1 0.5
1,2,3,7,8-Pe......................... \13\ C12-1,2,3,7,8-PeCDF 0.999-1.002 50 5 2.5
2,3,4,7,8-PeCDF...................... \13\ C12-2,3,4,7,8-PeCDF 0.999-1.002 50 5 2.5
1,2,3,7,8-PeCDD...................... \13\ C12-1,2,3,7,8-PeCDD 0.999-1.002 50 5 2.5
\13\ C12-2,3,7,8-TCDF................ \13\ C12-1,2,3,4-TCDD... 0.923-1.103
\13\ C12-2,3,7,8-TCDD................ \13\ C12-1,2,3,4-TCDD... 0.976-1.043
\13\ C12-2,3,7,8-TCDD................ \13\ C12-1,2,3,4-TCDD... 0.989-1.052
\13\ C12-1,2,3,7,8-PeCDF............. \13\ C12-1,2,3,4-TCDD... 1.000-1.425
\13\ C12-2,3,4,7,8-PeCDF............. \13\ C12-1,2,3,4-TCDD... 1.001-1.526
\13\ C12-1,2,3,7,8-PeCDF............. \13\ C12-1,2,3,4-TCDD... 1.000-1.567
----------------------------------------------------------------------------------------------------------------
Compounds using \13\ C12-1,2,3,7,8,9-HxCDD as the Injection Internal Standard
----------------------------------------------------------------------------------------------------------------
1,2,3,4,7,8-HxCDF.................... \13\ C12-1,2,3,4,7,8- 0.999-1.001 50 5 2.5
HxCDF.
1,2,3,6,7,8-HxCDF.................... \13\ C12-1,2,3,6,7,8- 0.997-1.005 50 5 2.5
HxCDF.
1,2,3,7,8,9-HxCDF.................... \13\ C12-1,2,3,7,8,9- 0.999-1.001 50 5 2.5
HxCDF.
2,3,4,6,7,8-HxCDF.................... \13\ C12-2,3,4,6,7,8- 0.999-1.001 50 5 2.5
HxCDF.
1,2,3,4,7,8-HxCDD.................... \13\ C12-1,2,3,4,7,8- 0.999-1.001 50 5 2.5
HxCDD.
1,2,3,6,7,8-HxCDD.................... \13\ C12-1,2,3,6,7,8- 0.998-1.004 50 5 2.5
HxCDD.
1,2,3,7,8,9-HxCDD.................... (\2\)................... 1.000-1.019 50 5 2.5
1,2,3,4,6,7,8-HpCDF.................. \13\ C12-1,2,3,4,6,7,8- 0.999-1.001 50 5 2.5
HpCDF.
[[Page 335]]
1,2,3,4,7,8,9-HpCDF.................. \13\ C12-1,2,3,4,7,8,9- 0.999-1.001 50 5 2.5
HpCDF.
1,2,3,4,6,7,8-HpCDD.................. \13\ C12-1,2,3,4,6,7,8- 0.999-1.001 50 5 2.5
HpCDD.
OCDF................................. \13\ C12-OCDD........... 0.999-1.001 100 10 5.0
OCDD................................. \13\ C12-OCDD........... 0.999-1.001 100 10 5.0
1,2,3,4,6,7,8,-HxCDF................. \13\ C12-1,2,3,7,8,9- 0.949-0.975
HpCDD.
\13\ C121,2,3,7,8,9-HxCDF............ \13\ C12-1,2,3,7,8,9- 0.977-1.047
HpCDD.
\13\ C122,3,4,6,7,8,-HxCDF........... \13\ C12-1,2,3,7,8,9- 0.959-1.021
HpCDD.
\13\ C121,2,3,4,7,8,-HxCDF........... \13\ C12-1,2,3,7,8,9- 0.977-1.000
HpCDD.
\13\ C121,2,3,6,7,8,-HxCDF........... \13\ C12-1,2,3,7,8,9- 0.981-1.003
HpCDD.
\13\ C121,2,3,4,6,7,8-HxCDF.......... \13\ C12-1,2,3,7,8,9- 1.043-1.085
HpCDD.
\13\ C121,2,3,4,7,8,9-HxCDF.......... \13\ C12-1,2,3,7,8,9- 1.057-1.151
HpCDD.
\13\ C121,2,3,4,6,7,8-HxCDF.......... \13\ C12-1,2,3,7,8,9- 1.086-1.110
HpCDD.
\13\ C12OCDD......................... \13\ C12-1,2,3,7,8,9- 1.032-1.311
HpCDD.
----------------------------------------------------------------------------------------------------------------
\1\ The Minimum Level (ML) for each analyte is defined as the level at which the entire analytical system must
give a recognizable signal and acceptable calibration point. It is equivalent to the concentration of the
lowest calibration standard, assuming that all method-specified sample weights, volumes, and cleanup
procedures have been employed.
\2\ The retention time reference for 1,2,3,7,8,9-HxCDD is \13\C12-1,2,3,6,7,8-HxCDD, and 1,2,3,7,8,9-HxCDD is
quantified using the averaged responses for \13\C12-1,2,3,4,7,8-HxCDD and \13\C12-1,2,3,6,7,8-HxCDD.
Table 3--Concentration of Stock and Spiking Solutions Containing CDDS/CDFS and Labeled Compounds
----------------------------------------------------------------------------------------------------------------
Labeled Labeled
compound compound PAR stock PAR spiking
CDD/CDF stock spiking solution solution \4\
solution \1\ solution \3\ (ng/mL) (ng/mL)
(ng/mL) \2\ (ng/mL)
----------------------------------------------------------------------------------------------------------------
2,3,7,8-TCDD.............................................. ............ ........... 40 0.8
2,3,7,8-TCDF.............................................. ............ ........... 40 0.8
1,2,3,7,8-PeCDD........................................... ............ ........... 200 4
1,2,3,7,8-PeCDF........................................... ............ ........... 200 4
2,3,4,7,8-PeCDF........................................... ............ ........... 200 4
1,2,3,4,7,8-HxCDD......................................... ............ ........... 200 4
1,2,3,6,7,8-HxCDD......................................... ............ ........... 200 4
1,2,3,7,8,9-HxCDD......................................... ............ ........... 200 4
1,2,3,4,7,8-HxCDF......................................... ............ ........... 200 4
1,2,3,6,7,8-HxCDF......................................... ............ ........... 200 4
1,2,3,7,8,9-HxCDF......................................... ............ ........... 200 4
2,3,4,6,7,8-HxCDF......................................... ............ ........... 200 4
1,2,3,4,6,7,8-HpCDD....................................... ............ ........... 200 4
1,2,3,4,6,7,8-HpCDF....................................... ............ ........... 200 4
1,2,3,4,7,8,9-HpCDF....................................... ............ ........... 200 4
OCDD...................................................... ............ ........... 400 8
OCDF...................................................... ............ ........... 400 8
\13\C12-2,3,7,8-TCDD...................................... 100 2
\13\C12-2,3,7,8-TCDF...................................... 100 2
\13\C12-1,2,3,7,8-PeCDD................................... 100 2
\13\C12-1,2,3,7,8-PeCDF................................... 100 2
\13\C12-2,3,4,7,8-PeCDF................................... 100 2
\13\C12-1,2,3,4,7,8-HxCDD................................. 100 2
\13\C12-1,2,3,6,7,8-HxCDD................................. 100 2
\13\C12-1,2,3,4,7,8-HxCDF................................. 100 2
\13\C12-1,2,3,6,7,8-HxCDF................................. 100 2
\13\C12-1,2,3,7,8,9-HxCDF................................. 100 2
\13\C12-2,3,4,6,7,8-HxCDF................................. 100 2
\13\C12-1,2,3,4,6,7,8-HpCDD............................... 100 2
\13\C12-1,2,3,4,6,7,8-HpCDF............................... 100 2
\13\C12-1,2,3,4,7,8,9-HpCDF............................... 100 2
\13\C12-OCDD.............................................. 200 4
Cleanup Standard \5\
\37\Cl4-2,3,7,8-TCDD.................................. 0.8
Internal Standards \6\
\13\C12-1,2,3,4-TCDD.................................. 200
\13\C12-1,2,3,7,8,9-HxCDD............................. 200
----------------------------------------------------------------------------------------------------------------
\1\ Section 7.10--prepared in nonane and diluted to prepare spiking solution.
\2\ Section 7.10.3--prepared in acetone from stock solution daily.
[[Page 336]]
\3\ Section 7.9--prepared in nonane and diluted to prepare spiking solution.
\4\ Section 7.14--prepared in acetone from stock solution daily.
\5\ Section 7.11--prepared in nonane and added to extract prior to cleanup.
\6\ Section 7.12--prepared in nonane and added to the concentrated extract immediately prior to injection into
the GC (Section 14.2).
Table 4--Concentration of CDDS/CDFS in Calibration and Calibration Verification Solutions \1\ (Section 15.3)
----------------------------------------------------------------------------------------------------------------
CDD/CDF CS2 (ng/mL) CS3 (ng/mL) CS4 (ng/mL) CS5 (ng/mL)
----------------------------------------------------------------------------------------------------------------
2,3,7,8-TCDD.................................. 0.5 2 10 40 200
2,3,7,8-TCDF.................................. 0.5 2 10 40 200
1,2,3,7,8-PeCDD............................... 2.5 10 50 200 1000
1,2,3,7,8-PeCDF............................... 2.5 10 50 200 1000
2,3,4,7,8-PeCDF............................... 2.5 10 50 200 1000
1,2,3,4,7,8-HxCDD............................. 2.5 10 50 200 1000
1,2,3,6,7,8-HxCDD............................. 2.5 10 50 200 1000
1,2,3,7,8,9-HxCDD............................. 2.5 10 50 200 1000
1,2,3,4,7,8-HxCDF............................. 2.5 10 50 200 1000
1,2,3,6,7,8-HxCDF............................. 2.5 10 50 200 1000
1,2,3,7,8,9-HxCDF............................. 2.5 10 50 200 1000
2,3,4,6,7,8-HxCDF............................. 2.5 10 50 200 1000
1,2,3,4,6,7,8-HpCDD........................... 2.5 10 50 200 1000
1,2,3,4,6,7,8-HpCDF........................... 2.5 10 50 200 1000
1,2,3,4,7,8,9-HpCDF........................... 2.5 10 50 200 1000
OCDD.......................................... 5.0 20 100 400 2000
OCDF.......................................... 5.0 20 100 400 2000
\13\ C12-2,3,7,8-TCDD......................... 100 100 100 100 100
\13\ C12-2,3,7,8-TCDF......................... 100 100 100 100 100
\13\ C12-1,2,3,7,8-PeCDD...................... 100 100 100 100 100
\13\ C12-PeCDF................................ 100 100 100 100 100
\13\ C12-2,3,4,7,8-PeCDF...................... 100 100 100 100 100
\13\ C12-1,2,3,4,7,8-HxCDD.................... 100 100 100 100 100
\13\ C12-1,2,3,6,7,8-HxCDD.................... 100 100 100 100 100
\13\ C12-1,2,3,4,7,8-HxCDF.................... 100 100 100 100 100
\13\ C12-1,2,3,6,7,8-HxCDF.................... 100 100 100 100 100
\13\ C12-1,2,3,7,8,9-HxCDF.................... 100 100 100 100 100
\13\ C12-1,2,3,4,6,7,8-HpCDD.................. 100 100 100 100 100
\13\ C12-1,2,3,4,6,7,8-HpCDF.................. 100 100 100 100 100
\13\ C12-1,2,3,4,7,8,9-Hp CDF................. 100 100 100 100 100
\13\ C12-OCDD................................. 200 200 200 200 200
Cleanup Standard:
\37\ C14-2,3,7,8-TCDD..................... 0.5 2 10 40 200
Internal Standards:
\13\ C12-1,2,3,4-TCDD......................... 100 100 100 100 100
\13\ C12-1,2,3,7,8,9-HxCDD.................... 100 100 100 100 100
----------------------------------------------------------------------------------------------------------------
Table 5--GC Retention Time Window Defining Solution and Isomer Specificity Test Standard (Section 7.15)
----------------------------------------------------------------------------------------------------------------
DB-5 column GC retention-time window defining solution
-----------------------------------------------------------------------------------------------------------------
CDD/CDF First eluted Last eluted
----------------------------------------------------------------------------------------------------------------
TCDF................................. 1,3,6,8-.................................. 1,2,8,9-
TCDD................................. 1,3,6,8-.................................. 1,2,8,9-
PeCDF................................ 1,3,4,6,8-................................ 1,2,3,8,9-
PeCDD................................ 1,2,4,7,9-................................ 1,2,3,8,9-
HxCDF................................ 1,2,3,4,6,8-.............................. 1,2,3,4,8,9-
HxCDD................................ 1,2,4,6,7,9-.............................. 1,2,3,4,6,7-
HpCDF................................ 1,2,3,4,6,7,8-............................ 1,2,3,4,7,8,9-
HpCDD................................ 1,2,3,4,6,7,9-............................ 1,2,3,4,6,7,8-
----------------------------------------------------------------------------------------------------------------
DB-5 Column TCDD Specificity Test Standard
1,2,3,7 = 1,2,3,8-TCDD
2,3,7,8-TCDD
1,2,3,9-TCDD
DB-225 Column TCDF Isomer Specificity Test Standard
2,3,4,7-TCDF
2,3,7,8-TCDF
1,2,3,9-TCDF
[[Page 337]]
Table 6--Acceptance Criteria for Performance Tests When All CDDS/CDFS Are Tested \1\
----------------------------------------------------------------------------------------------------------------
IPR \2 3\
CDD/CDF Test conc. ---------------------------- OPR (ng/mL) VER (ng/mL)
(ng/mL) s (ng/mL) X (ng/mL)
----------------------------------------------------------------------------------------------------------------
2,3,7,8-TCDD............................... 10 2.8 8.3-12.9 6.7-15.8 7.8-12.9
2,3,7,8-TCDF............................... 10 2.0 8.7-13.7 7.5-15.8 8.4-12.0
1,2,3,7,8-PeCDD............................ 50 7.5 38-66 35-71 39-65
1,2,3,7,8-PeCDF............................ 50 7.5 43-62 40-67 41-60
2,3,4,7,8-PeCDF............................ 50 8.6 36-75 34-80 41-61
1,2,3,4,7,8-HxCDD.......................... 50 9.4 39-76 35-82 39-64
1,2,3,6,7,8-HxCDD.......................... 50 7.7 42-62 38-67 39-64
1,2,3,7,8,9-HxCDD.......................... 50 11.1 37-71 32-81 41-61
1,2,3,4,7,8-HxCDF.......................... 50 8.7 41-59 36-67 45-56
1,2,3,6,7,8-HxCDF.......................... 50 6.7 46-60 42-65 44-57
1,2,3,7,8,9-HxCDF.......................... 50 6.4 42-61 39-65 45-56
2,3,4,6,7,8-HxCDF.......................... 50 7.4 37-74 35-78 44-57
1,2,3,4,6,7,8-HpCDD........................ 50 7.7 38-65 35-70 43-58
1,2,3,4,6,7,8-HpCDF........................ 50 6.3 45-56 41-61 45-55
1,2,3,4,7,8,9-HpCDF........................ 50 8.1 43-63 39-69 43-58
OCDD....................................... 100 19 89-127 78-144 79-126
OCDF....................................... 100 27 74-146 63-170 63-159
\13\C12-2,3,7,8-TCDD....................... 100 37 28-134 20-175 82-121
\13\C12-2,3,7,8-TCDF....................... 100 35 31-113 22-152 71-140
\13\C12-1,2,3,7,8-PeCDD.................... 100 39 27-184 21-227 62-160
\13\C12-1,2,3,7,8-PeCDF.................... 100 34 27-156 21-192 76-130
\13\C12-2,3,4,7,8-PeCDF.................... 100 38 16-279 13-328 77-130
\13\C12-1,2,3,4,7,8-HxCDD.................. 100 41 29-147 21-193 85-117
\13\C12-1,2,3,6,7,8-HxCDD.................. 100 38 34-122 25-163 85-118
\13\C12-1,2,3,4,7,8-HxCDF.................. 100 43 27-152 19-202 76-131
\13\C12-1,2,3,6,7,8-HxCDF.................. 100 35 30-122 21-159 70-143
\13\C12-1,2,3,7,8,9-HxCDF.................. 100 40 24-157 17-205 74-135
\13\C12-2,3,4,6,7,8,-HxCDF................. 100 37 29-136 22-176 73-137
\13\C12-1,2,3,4,6,7,8-HpCDD................ 100 35 34-129 26-166 72-138
\13\C12-1,2,3,4,6,7,8-HpCDF................ 100 41 32-110 21-158 78-129
\13\C12-1,2,3,4,7,8,9-HpCDF................ 100 40 28-141 20-186 77-129
\13\C12-OCDD............................... 200 95 41-276 26-397 96-415
\37\Cl4-2,3,7,8-TCDD....................... 10 3.6 3.9-15.4 3.1-19.1 7.9-12.7
----------------------------------------------------------------------------------------------------------------
\1\ All specifications are given as concentration in the final extract, assuming a 20 [micro]L volume.
\2\ s = standard deviation of the concentration.
\3\ X = average concentration.
Table 6a--Acceptance Criteria for Performance Tests When Only Tetra Compounds are Tested \1\
----------------------------------------------------------------------------------------------------------------
IPR \2 3\
CDD/CDF Test Conc. --------------------------- OPR (ng/mL) VER (ng/mL)
(ng/mL) s (ng/mL) X (ng/mL)
----------------------------------------------------------------------------------------------------------------
2,3,7,8-TCDD................................ 10 2.7 8.7-12.4 7.314.6 8.2-12.3
2,3,7,8-TCDF................................ 10 2.0 9.1-13.1 8.0-14.7 8.6-11.6
\13\C12-2,3,7,8-TCDD........................ 100 35 32-115 25-141 85-117
\13\C12-2,3,7,8-TCDF........................ 100 34 35-99 26-126 76-131
\37\Cl4-2,3,7,8-TCDD........................ 10 3.4 4.5-13.4 3.7-15.8 8.3-12.1
----------------------------------------------------------------------------------------------------------------
\1\ All specifications are given as concentration in the final extract, assuming a 20 [micro]L volume.
\2\ s = standard deviation of the concentration.
\3\ X = average concentration.
Table 7--Labeled Compounds Recovery in Samples When all CDDS/CDFS are
Tested
------------------------------------------------------------------------
Labeled compound recovery
Compound Test conc. --------------------------
(ng/mL) (ng/mL) \1\ (%)
------------------------------------------------------------------------
\13\C12-2,3,7,8-TCDD............ 100 25-164 25-164
\13\C12-2,3,7,8-TCDF............ 100 24-169 24-169
\13\C12-1,2,3,7,8-PeCDD......... 100 25-181 25-181
\13\C12-1,2,3,7,8-PeCDF......... 100 24-185 24-185
\13\C12-2,3,4,7,8-PeCDF......... 100 21-178 21-178
\13\C12-1,2,3,4,7,8-HxCDD....... 100 32-141 32-141
\13\C12-1,2,3,6,7,8-HxCDD....... 100 28-130 28-130
\13\C12-1,2,3,4,7,8-HxCDF....... 100 26-152 26-152
\13\C12-1,2,3,6,7,8-HxCDF....... 100 26-123 26-123
[[Page 338]]
\13\C12-1,2,3,7,8,9-HxCDF....... 100 29-147 29-147
\13\C12-2,3,4,6,7,8-HxCDF....... 100 28-136 28-136
\13\C12-1,2,3,4,6,7,8-HpCDD..... 100 23-140 23-140
\13\C12-1,2,3,4,6,7,8-HpCDF..... 100 28-143 28-143
\13\C12-1,2,3,4,7,8,9-HpCDF..... 100 26-138 26-138
\13\C12-OCDD.................... 200 34-313 17-157
\37\Cl4-2,3,7,8-TCDD............ 10 3.5-19.7 35-197
------------------------------------------------------------------------
\1\ Specification given as concentration in the final extract, assuming
a 20-[micro]L volume.
Table 7a--Labeled Compound Recovery in Samples When Only Tetra Compounds
are Tested
------------------------------------------------------------------------
Labeled compound recovery
Compound Test conc. --------------------------
(ng/mL) (ng/mL) \1\ (%)
------------------------------------------------------------------------
\13\C12-2,3,7,8-TCDD............ 100 31-137 31-137
\13\C12-2,3,7,8-TCDF............ 100 29-140 29-140
\37\Cl4-2,3,7,8-TCDD............ 10 4.2-16.4 42-164
------------------------------------------------------------------------
\1\ Specification given as concentration in the final extract, assuming
a 20 [micro]L volume.
Table 8--Descriptors, Exact M/Z's, M/Z Types, and Elemental Compositions of the CDDs and CDFs
----------------------------------------------------------------------------------------------------------------
Exact M/Z
Descriptor \1\ M/Z type Elemental composition Substance \2\
----------------------------------------------------------------------------------------------------------------
1........................ 292.9825 Lock C7F11.................... PFK
303.9016 M C12H4\35\Cl4O............ TCDF
305.8987 M = 2 C12H4\35\Cl3\37\ClO...... TCDF
315.9419 M \13\C12H4\35\Cl4O........ TCDF \3\
317.9389 M = 2 \13\C12H4\35\Cl3\37\ClO.. TCDF \3\
319.8965 M C12H4\35\Cl4O2........... TCDD
321.8936 M = 2 C12H4\35\Cl3\37\ClO2..... TCDD
327.8847 M C12H4\37\Cl4O2........... TCDD \4\
330.9792 QC C7F13.................... PFK
331.9368 M \13\C12H4\35\Cl4O2....... TCDD \3\
333.9339 M = 2 \13\C12H4\35\Cl3\37\ClO2. TCDD \3\
375.8364 M = 2 C12H4\35\Cl5\37\ClO...... HxCDPE
2........................ 339.8597 M = 2 C12H3\35\Cl4\37\ClO...... PeCDF
341.8567 M = 4 C12H3\35\Cl3\37\Cl2O..... PeCDF
351.9000 M = 2 \13\C12H3\35\Cl4\37\ClO.. PeCDF
353.8970 M = 4 \13\C12H3\35\Cl3\37\Cl2O. PeCDF \3\
354.9792 Lock C9F13.................... PFK
355.8546 M = 2 C12H3\35\Cl4\37\ClO2..... PeCDD
357.8516 M = 4 C12H3\35\Cl3\37\Cl2O2.... PeCDD
367.8949 M = 2 \13\C12H3\35\Cl4\37\ClO2. PeCDD \3\
369.8919 M = 4 \13\C12H3\35\Cl3\37\Cl2O2 PeCDD \3\
409.7974 M = 2 C12H3\35\Cl6\37\ClO...... HpCDPE
3........................ 373.8208 M = 2 C12H2\35\Cl5\37\ClO...... HxCDF
375.8178 M = 4 C12H2\35\Cl4\37\Cl2O..... HxCDF
383.8639 M \13\C12H2\35\Cl6O........ HxCDF \3\
385.8610 M = 2 \13\C12H2\35\Cl5\37\ClO.. HxCDF \3\
389.8157 M = 2 C12H2\35\Cl5\37\ClO2..... HxCDD
391.8127 M = 4 C12H2\35\Cl4\37\Cl2O2.... HxCDD
392.9760 Lock C9F15.................... PFK
401.8559 M = 2 \13\C12H2\35\Cl5\37\ClO2. HxCDD \3\
403.8529 M = 4 \13\C12H2\35\Cl4\37\Cl2O2 HxCDD \3\
430.9729 QC C9F17.................... PFK
445.7555 M = 4 C12H2\35\Cl6\37\Cl2O..... OCDPE
4........................ 407.7818 M = 2 C12H\35\Cl6\37\ClO....... HpCDF
409.7789 M = 4 C12H\35\Cl5\37\Cl2O...... HpCDF
417.8253 M \13\C12H\35\Cl7O......... HpCDF \3\
419.8220 M = 2 \13\C12H\35\Cl6\37\ClO... HpCDF \3\
423.7766 M = 2 C12H\35\Cl6\37\ClO2...... HpCDD
425.7737 M = 4 C12H\35\Cl5\37\Cl2O2..... HpCDD
[[Page 339]]
430.9729 Lock C9F17.................... PFK
435.8169 M = 2 \13\C12H\35\Cl6\37\ClO2.. HpCDD \3\
437.8140 M = 4 \13\C12H\35\Cl5\37\Cl2O2. HpCDD \3\
479.7165 M = 4 C12H\35\Cl7\37\Cl2O...... NCDPE
5........................ 441.7428 M = 2 C12\35\Cl7\37\ClO........ OCDF
442.9728 Lock C10F17................... PFK
443.7399 M = 4 C12\35\Cl6\37\Cl2O....... OCDF
457.7377 M = 2 C12\35\Cl7\37\ClO2....... OCDD
459.7348 M = 4 C12\35\Cl6\37\Cl2O2...... OCDD
469.7779 M = 2 \13\C12\35\Cl7\37\ClO2... OCDD \3\
471.7750 M = 4 \13\C12\35\Cl6\37\Cl2O2.. OCDD \3\
513.6775 M = 4 C12\35\Cl8\37\Cl2O....... DCDPE
----------------------------------------------------------------------------------------------------------------
\1\ Nuclidic masses used:
H = 1.007825.
O = 15.994915.
C = 12.00000.
\35\Cl = 34.968853.
\13\C = 13.003355.
\37\Cl = 36.965903.
F = 18.9984.
\2\ TCDD = Tetrachlorodibenzo-p-dioxin.
PeCDD = Pentachlorodibenzo-p-dioxin.
HxCDD = Hexachlorodibenzo-p-dioxin.
HpCDD = Heptachlorodibenzo-p-dioxin.
OCDD = Octachlorodibenzo-p-dioxin.
HxCDPE = Hexachlorodiphenyl ether.
OCDPE = Octachlorodiphenyl ether.
DCDPE = Decachlorodiphenyl ether.
TCDF = Tetrachlorodibenzofuran.
PeCDF = Pentachlorodibenzofuran.
HxCDF = Hexachlorodibenzofuran.
HpCDF = Heptachlorodibenzofuran.
OCDF = Octachlorodibenzofuran.
HpCDPE = Heptachlorodiphenyl ether.
NCDPE = Nonachlorodiphenyl ether.
PFK = Perfluorokerosene.
\3\ Labeled compound.
\4\ There is only one m/z for \37\Cl4-2,3,7,8,-TCDD (cleanup standard).
Table 9--Theoretical Ion Abundance Ratios and QC Limits
----------------------------------------------------------------------------------------------------------------
QC limit \1\
Number of chlorine atoms M/Z's forming ratio Theoretical -------------------------
ratio Lower Upper
----------------------------------------------------------------------------------------------------------------
4 \2\................................... M/(M = 2)...................... 0.77 0.65 0.89
5....................................... (M = 2)/(M = 4)................ 1.55 1.32 1.78
6....................................... (M = 2)/(M = 4)................ 1.24 1.05 1.43
6 \3\................................... M/(M = 2)...................... 0.51 0.43 0.59
7....................................... (M = 2)/(M = 4)................ 1.05 0.88 1.20
7 \4\................................... M/(M = 2)...................... 0.44 0.37 0.51
8....................................... (M = 2)/(M = 4)................ 0.89 0.76 1.02
----------------------------------------------------------------------------------------------------------------
\1\ QC limits represent 15% windows around the theoretical ion abundance ratios.
\2\ Does not apply to \37\Cl4-2,3,7,8-TCDD (cleanup standard).
\3\ Used for \13\C12-HxCDF only.
\4\ Used for \13\C12-HpCDF only.
Table 10--Suggested Sample Quantities To Be Extracted for Various Matrices \1\
----------------------------------------------------------------------------------------------------------------
Quantity
Sample Matrix \2\ Example Percent solids Phase extracted
----------------------------------------------------------------------------------------------------------------
Single-phase:
Aqueous...................... Drinking water...... <1 (\3\)............... 1000 mL.
Groundwater
Treated wastewater
Solid........................ Dry soil............ 20 Solid............... 10 g.
Compost
Ash
Organic...................... Waste solvent....... <1 Organic............. 10 g.
Waste oil
Organic polymer
Tissue....................... Fish................ .............. Organic............. 10 g.
Human adipose
[[Page 340]]
Multi-phase:
Liquid/Solid:
Aqueous/Solid............ Wet soil............ 1-30 Solid............... 10 g.
Untreated effluent..
Digested municipal
sludge.
Filter cake.........
Paper pulp..........
Organic/solid............ Industrial sludge... 1-100 Both................ 10 g.
Oily waste
Liquid/Liquid:
Aqueous/organic.......... In-process effluent. <1 Organic............. 10 g.
Untreated effluent
Drum waste
Aqueous/organic/solid.... Untreated effluent.. 1 Organic and solid... 10 g.
Drum waste
----------------------------------------------------------------------------------------------------------------
\1\ The quantity of sample to be extracted is adjusted to provide 10 g of solids (dry weight). One liter of
aqueous samples containing 1% solids will contain 10 g of solids. For aqueous samples containing greater than
1% solids, a lesser volume is used so that 10 g of solids (dry weight) will be extracted.
\2\ The sample matrix may be amorphous for some samples. In general, when the CDDs/CDFs are in contact with a
multiphase system in which one of the phases is water, they will be preferentially dispersed in or adsorbed on
the alternate phase because of their low solubility in water.
\3\ Aqueous samples are filtered after spiking with the labeled compounds. The filtrate and the materials
trapped on the filter are extracted separately, and the extracts are combined for cleanup and analysis.
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24.0 Glossary of Definitions and Purposes
These definitions and purposes are specific to this method but have
been conformed to common usage as much as possible.
24.1 Units of weight and Measure and Their Abbreviations.
24.1.1 Symbols:
[deg]C--degrees Celsius
[micro]L--microliter
[micro]m--micrometer
<--less than
--greater than
%--percent
24.1.2 Alphabetical abbreviations:
amp--ampere
cm--centimeter
g--gram
h--hour
D--inside diameter
in.--inch
L--liter
M--Molecular ion
m--meter
mg--milligram
min--minute
mL--milliliter
mm--millimeter
m/z--mass-to-charge ratio
[[Page 348]]
N--normal; gram molecular weight of solute divided by hydrogen
equivalent of solute, per liter of solution
OD--outside diameter
pg--picogram
ppb--part-per-billion
ppm--part-per-million
ppq--part-per-quadrillion
ppt--part-per-trillion
psig--pounds-per-square inch gauge
v/v--volume per unit volume
w/v--weight per unit volume
24.2 Definitions and Acronyms (in Alphabetical Order).
Analyte--A CDD or CDF tested for by this method. The analytes are
listed in Table 1.
Calibration Standard (CAL)--A solution prepared from a secondary
standard and/or stock solutions and used to calibrate the response of
the instrument with respect to analyte concentration.
Calibration Verification Standard (VER)--The mid-point calibration
standard (CS3) that is used in to verify calibration. See Table 4.
CDD--Chlorinated Dibenzo-p-ioxin--The isomers and congeners of
tetra-through octa-chlorodibenzo-p-dioxin.
CDF--Chlorinated Dibenzofuran--The isomers and congeners of tetra-
through octa-chlorodibenzofuran.
CS1, CS2, CS3, CS4, CS5--See Calibration standards and Table 4.
Field Blank--An aliquot of reagent water or other reference matrix
that is placed in a sample container in the laboratory or the field, and
treated as a sample in all respects, including exposure to sampling site
conditions, storage, preservation, and all analytical procedures. The
purpose of the field blank is to determine if the field or sample
transporting procedures and environments have contaminated the sample.
GC--Gas chromatograph or gas chromatography.
GPC--Gel permeation chromatograph or gel permeation chromatography.
HPLC--High performance liquid chromatograph or high performance
liquid chromatography.
HRGC--High resolution GC.
HRMS--High resolution MS.
IPR--Initial precision and recovery; four aliquots of the diluted
PAR standard analyzed to establish the ability to generate acceptable
precision and accuracy. An IPR is performed prior to the first time this
method is used and any time the method or instrumentation is modified.
K-D--Kuderna-Danish concentrator; a device used to concentrate the
analytes in a solvent.
Laboratory Blank--See method blank.
Laboratory Control sample (LCS)--See ongoing precision and recovery
standard (OPR).
Laboratory Reagent Blank--See method blank.
May--This action, activity, or procedural step is neither required
nor prohibited.
May Not--This action, activity, or procedural step is prohibited.
Method Blank--An aliquot of reagent water that is treated exactly as
a sample including exposure to all glassware, equipment, solvents,
reagents, internal standards, and surrogates that are used with samples.
The method blank is used to determine if analytes or interferences are
present in the laboratory environment, the reagents, or the apparatus.
Minimum Level (ML)--The level at which the entire analytical system
must give a recognizable signal and acceptable calibration point for the
analyte. It is equivalent to the concentration of the lowest calibration
standard, assuming that all method-specified sample weights, volumes,
and cleanup procedures have been employed.
MS--Mass spectrometer or mass spectrometry.
Must--This action, activity, or procedural step is required.
OPR--Ongoing precision and recovery standard (OPR); a laboratory
blank spiked with known quantities of analytes. The OPR is analyzed
exactly like a sample. Its purpose is to assure that the results
produced by the laboratory remain within the limits specified in this
method for precision and recovery.
PAR--Precision and recovery standard; secondary standard that is
diluted and spiked to form the IPR and OPR.
PFK--Perfluorokerosene; the mixture of compounds used to calibrate
the exact m/z scale in the HRMS.
Preparation Blank--See method blank.
Primary Dilution Standard--A solution containing the specified
analytes that is purchased or prepared from stock solutions and diluted
as needed to prepare calibration solutions and other solutions.
Quality Control Check Sample (QCS)--A sample containing all or a
subset of the analytes at known concentrations. The QCS is obtained from
a source external to the laboratory or is prepared from a source of
standards different from the source of calibration standards. It is used
to check laboratory performance with test materials prepared external to
the normal preparation process.
Reagent Water--Water demonstrated to be free from the analytes of
interest and potentially interfering substances at the method detection
limit for the analyte.
Relative Standard Deviation (RSD)--The standard deviation times 100
divided by the mean. Also termed ``coefficient of variation.''
RF--Response factor. See Section 10.6.1.
RR--Relative response. See Section 10.5.2.
RSD--See relative standard deviation.
[[Page 349]]
SDS--Soxhlet/Dean-Stark extractor; an extraction device applied to
the extraction of solid and semi-solid materials (Reference 7).
Should--This action, activity, or procedural step is suggested but
not required.
SICP--Selected ion current profile; the line described by the signal
at an exact m/z.
SPE--Solid-phase extraction; an extraction technique in which an
analyte is extracted from an aqueous sample by passage over or through a
material capable of reversibly adsorbing the analyte. Also termed
liquid-solid extraction.
Stock Solution--A solution containing an analyte that is prepared
using a reference material traceable to EPA, the National Institute of
Science and Technology (NIST), or a source that will attest to the
purity and authenticity of the reference material.
TCDD--Tetrachlorodibenzo-p-dioxin.
TCDF--Tetrachlorodibenzofuran.
VER--See calibration verification standard.
Method 1624 Revision B--Volatile Organic Compounds by Isotope Dilution
GC/MS
1. Scope and Application
1.1 This method is designed to determine the volatile toxic organic
pollutants associated with the 1976 Consent Decree and additional
compounds amenable to purge and trap gas chromatography-mass
spectrometry (GC/MS).
1.2 The chemical compounds listed in table 1 may be determined in
municipal and industrial discharges by this method. The methmd is
designed to meet the survey requirements of Effluent Guidelines Division
(EGD) and the National Pollutants Discharge Elimination System (NPDES)
under 40 CFR 136.1 and 136.5. Any modifications of this method, beyond
those expressly permitted, shall be considered as major modifications
subject to application and approval of alternate test procedures under
40 CFR 136.4 and 136.5.
1.3 The detection limit of this method is usually dependent on the
level of interferences rather than instrumental limitations. The limits
in table 2 represent the minimum quantity that can be detected with no
interferences present.
1.4 The GC/MS portions of this method are for use only by analysts
experienced with GC/MS or under the close supervision of such qualified
persons. Laboratories unfamiliar with the analyses of environmental
samples by GC/MS should run the performance tests in reference 1 before
beginning.
2. Summary of Method
2.1 Stable isotopically labeled analogs of the compounds of interest
are added to a 5 mL water sample. The sample is purged at 20-25 [deg]C
with an inert gas in a specially designed chamber. The volatile organic
compounds are transferred from the aqueous phase into the gaseous phase
where they are passed into a sorbent column and trapped. After purging
is completed, the trap is backflushed and heated rapidly to desorb the
compounds into a gas chromatograph (GC). The compounds are separated by
the GC and detected by a mass spectrometer (MS) (references 2 and 3).
The labeled compounds serve to correct the variability of the analytical
technique.
2.2 Identification of a compound (qualitative analysis) is performed
by comparing the GC retention time and the background corrected
characteristic spectral masses with those of authentic standards.
2.3 Quantitative analysis is performed by GC/MS using extracted ion
current profile (EICP) areas. Isotope dilution is used when labeled
compounds are available; otherwise, an internal standard method is used.
2.4 Quality is assured through reproducible calibration and testing
of the purge and trap and GC/MS systems.
3. Contamination and Interferences
3.1 Impurities in the purge gas, organic compounds out-gassing from
the plumbing upstream of the trap, and solvent vapors in the laboratory
account for the majority of contamination problems. The analytical
system is demonstrated to be free from interferences under conditions of
the analysis by analyzing blanks initially and with each sample lot
(samples analyzed on the same 8 hr shift), as described in Section 8.5.
3.2 Samples can be contaminated by diffusion of volatile organic
compounds (particularly methylene chloride) through the bottle seal
during shipment and storage. A field blank prepared from reagent water
and carried through the sampling and handling protocol serves as a check
on such contamination.
3.3 Contamination by carry-over can occur when high level and low
level samples are analyzed sequentially. To reduce carry-over, the
purging device and sample syringe are rinsed between samples with
reagent water. When an unusually concentrated sample is encountered, it
is followed by analysis of a reagent water blank to check for carry-
over. For samples containing large amounts of water soluble materials,
suspended solids, high boiling compounds, or high levels or purgeable
compounds, the purge device is washed with soap solution, rinsed with
tap and distilled water, and dried in an oven at 100-125 [deg]C. The
trap and other parts of the system are also subject to contamination;
therefore, frequent bakeout and purging of the entire system may be
required.
3.4 Interferences resulting from samples will vary considerably from
source to source, depending on the diversity of the industrial complex
or municipality being sampled.
[[Page 350]]
4. Safety
4.1 The toxicity or carcinogenicity of each compound or reagent used
in this method has not been precisely determined; however, each chemical
compound should be treated as a potential health hazard. Exposure to
these compounds should be reduced to the lowest possible level. The
laboratory is responsible for maintaining a current awareness file of
OSHA regulations regarding the safe handling of the chemicals specified
in this method. A reference file of data handling sheets should also be
made available to all personnel involved in these analyses. Additional
information on laboratory safety can be found in references 4-6.
4.2 The following compounds covered by this method have been
tentatively classified as known or suspected human or mammalian
carcinogens: benzene, carbon tetrachloride, chloroform, and vinyl
chloride. Primary standards of these toxic compounds should be prepared
in a hood, and a NIOSH/MESA approved toxic gas respirator should be worn
when high concentrations are handled.
5. Apparatus and Materials
5.1 Sample bottles for discrete sampling.
5.1.1 Bottle--25 to 40 mL with screw cap (Pierce 13075, or
equivalent). Detergent wash, rinse with tap and distilled water, and dry
at 105 [deg]C for one hr minimum before use.
5.1.2 Septum--Teflon-faced silicone (Pierce 12722, or equivalent),
cleaned as above and baked at 100-200 [deg]C, for one hour minimum.
5.2 Purge and trap device--consists of purging device, trap, and
desorber. Complete devices are commercially available.
5.2.1 Purging device--designed to accept 5 mL samples with water
column at least 3 cm deep. The volume of the gaseous head space between
the water and trap shall be less than 15 mL. The purge gas shall be
introduced less than 5 mm from the base of the water column and shall
pass through the water as bubbles with a diameter less than 3 mm. The
purging device shown in Figure 1 meets these criteria.
5.2.2 Trap--25 to 30 cm x 2.5 mm i.d. minimum, containing the
following:
5.2.2.1 Methyl silicone packing--one 0.2 cm, 3
percent OV-1 on 60/80 mesh Chromosorb W, or equivalent.
5.2.2.2 Porous polymer--15 1.0 cm, Tenax GC
(2,6-diphenylene oxide polymer), 60/80 mesh, chromatographic grade, or
equivalent.
5.2.2.3 Silica gel--8 1.0 cm, Davison
Chemical, 35/60 mesh, grade 15, or equivalent. The trap shown in Figure
2 meets these specifications.
5.2.3 Desorber--shall heat the trap to 175 5
[deg]C in 45 seconds or less. The polymer section of the trap shall not
exceed 180 [deg]C, and the remaining sections shall not exceed 220
[deg]C. The desorber shown in Figure 2 meets these specifications.
5.2.4 The purge and trap device may be a separate unit or coupled to
a GC as shown in Figures 3 and 4.
5.3 Gas chromatograph--shall be linearly temperature programmable
with initial and final holds, shall contain a glass jet separator as the
MS interface, and shall produce results which meet the calibration
(Section 7), quality assurance (Section 8), and performance tests
(Section 11) of this method.
5.3.1 Column--2.8 0.4 m x 2 0.5 mm i. d. glass, packekd with one percent SP-1000 on
Carbopak B, 60/80 mesh, or equivalent.
5.4 Mass spectrometer--70 eV electron impact ionization; shall
repetitively scan from 20 to 250 amu every 2-3 seconds, and produce a
unit resolution (valleys between m/z 174-176 less than 10 percent of the
height of the m/z 175 peak), background corrected mass spectrum from 50
ng 4-bromo-fluorobenzene (BFB) injected into the GC. The BFB spectrum
shall meet the mass-intensity criteria in Table 3. All portions of the
GC column, transfer lines, and separator which connect the GC column to
the ion source shall remain at or above the column temperature during
analysis to preclude condensation of less volatile compounds.
5.5 Data system--shall collect and record MS data, store mass
intensity data in spectral libraries, process GC/MS data and generate
reports, and shall calculate and record response factors.
5.5.1 Data acquisition--mass spectra shall be collected continuously
throughout the analysis and stored on a mass storage device.
5.5.2 Mass spectral libraries--user created libraries containing
mass spectra obtained from analysis of authentic standards shall be
employed to reverse search GC/MS runs for the compounds of interest
(Section 7.2).
5.5.3 Data processing--the data system shall be used to search,
locate, identify, and quantify the compounds of interest in each GC/MS
analysis. Software routines shall be employed to compute retention times
and EICP areas. Displays of spectra, mass chromatograms, and library
comparisons are required to verify results.
5.5.4 Response factors and multipoint calibrations--the data system
shall be used to record and maintain lists of response factors (response
ratios for isotope dilution) and generate multi-point calibration curves
(Section 7). Computations of relative standard deviation (coefficient of
variation) are useful for testing calibration linearity. Statistics on
initial and on-going performance shall be maintained (Sections 8 and
11).
5.6 Syringes--5 mL glass hypodermic, with Luer-lok tips.
5.7 Micro syringes--10, 25, and 100 uL.
5.8 Syringe valves--2-way, with Luer ends (Telfon or Kel-F).
[[Page 351]]
5.9 Syringe--5 mL, gas-tight, with shut-off valve.
5.10 Bottles--15 mL., screw-cap with Telfon liner.
5.11 Balance--analytical, capable of weighing 0.1 mg.
6. Reagents and Standards
6.1 Reagent water--water in which the compounds of interest and
interfering compounds are not detected by this method (Section 11.7). It
may be generated by any of the following methods:
6.1.1 Activated carbon--pass tap water through a carbon bed (Calgon
Filtrasorb-300, or equivalent).
6.1.2 Water purifier--pass tap water through a purifier (Millipore
Super Q, or equivalent).
6.1.3 Boil and purge--heat tap water to 90-100 [deg]C and bubble
contaminant free inert gas through it for approx one hour. While still
hot, transfer the water to screw-cap bottles and seal with a Teflon-
lined cap.
6.2 Sodium thiosulfate--ACS granular.
6.3 Methanol--pesticide quality or equivalent.
6.4 Standard solutions--purchased as solution or mixtures with
certification to their purity, concentration, and authenticity, or
prepared from materials of known purity and composition. If compound
purity is 96 percent or greater, the weight may be used without
correction to calculate the concentration of the standard.
6.5 Preparation of stock solutions--prepare in methanol using liquid
or gaseous standards per the steps below. Observe the safety precautions
given in Section 4.
6.5.1 Place approx 9.8 mL of methanol in a 10 mL ground glass
stoppered volumetric flask. Allow the flask to stand unstoppered for
approximately 10 minutes or until all methanol wetted surfaces have
dried. In each case, weigh the flask, immediately add the compound, then
immediately reweigh to prevent evaporation losses from affecting the
measurement.
6.5.1.1 Liquids--using a 100 [micro]L syringe, permit 2 drops of
liquid to fall into the methanol without contacting the leck of the
flask. Alternatively, inject a known volume of the compound into the
methanol in the flask using a micro-syringe.
6.5.1.2 Gases (chloromethane, bromomethane, chloroethane, vinyl
chloride)--fill a valved 5 mL gas-tight syringe with the compound. Lower
the needle to approximately 5 mm above the methanol meniscus. Slowly
introduce the compound above the surface of the meniscus. The gas will
dissolve rapidly in the methanol.
6.5.2 Fill the flask to volume, stopper, then mix by inverting
several times. Calculate the concentration in mg/mL ([micro]g/[micro]L)
from the weight gain (or density if a known volume was injected).
6.5.3 Transfer the stock solution to a Teflon sealed screw-cap-
bottle. Store, with minimal headspace, in the dark at -10 to -20 [deg]C.
6.5.4 Prepare fresh standards weekly for the gases and 2-
chloroethylvinyl ether. All other standards are replaced after one
month, or sooner if comparison with check standards indicate a change in
concentration. Quality control check standards that can be used to
determine the accuracy of calibration standards are available from the
US Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio.
6.6 Labeled compound spiking solution--from stock standard solutions
prepared as above, or from mixtures, prepare the spiking solution to
contain a concentration such that a 5-10 [micro]L spike into each 5 mL
sample, blank, or aqueous standard analyzed will result in a
concentration of 20 [micro]g/L of each labeled compound. For the gases
and for the water soluble compounds (acrolein, acrylonitrile, acetone,
diethyl ether, and MEK), a concentration of 100 [micro]g/L may be used.
Include the internal standards (Section 7.5) in this solution so that a
concentration of 20 [micro]g/L in each sample, blank, or aqueous
standard will be produced.
6.7 Secondary standards--using stock solutions, prepare a secondary
standard in methanol to contain each pollutant at a concentration of 500
[micro]g/mL For the gases and water soluble compounds (Section 6.6), a
concentration of 2.5 mg/mL may be used.
6.7.1 Aqueous calibration standards--using a 25 [micro]L syringe,
add 20 [micro]L of the secondary standard (Section 6.7) to 50, 100, 200,
500, and 1000 mL of reagent water to produce concentrations of 200, 100,
50, 20, and 10 [micro]g/L, respectively. If the higher concentration
standard for the gases and water soluble compounds was chosen (Section
6.6), these compounds will be at concentrations of 1000, 500, 250, 100,
and 50 [micro]g/L in the aqueous calibration standards.
6.7.2 Aqueous performance standard--an aqueous standard containing
all pollutants, internal standards, labeled compounds, and BFB is
prepared daily, and analyzed each shift to demonstrate performance
(Section 11). This standard shall contain either 20 or 100 [micro]g/L of
the labeled and pollutant gases and water soluble compounds, 10
[micro]g/L BFB, and 20 [micro]g/L of all other pollutants, labeled
compounds, and internal standards. It may be the nominal 20 [micro]g/L
aqueous calibration standard (Section 6.7.1).
6.7.3 A methanolic standard containing all pollutants and internal
standards is prepared to demonstrate recovery of these compounds when
syringe injection and purge and trap analyses are compared. This
standard shall contain either 100 [micro]g/mL or 500 [micro]g/mL of the
gases and water soluble compounds, and 100 [micro]g/mL of the remaining
pollutants
[[Page 352]]
and internal standards (consistent with the amounts in the aqueous
performance standard in 6.7.2).
6.7.4 Other standards which may be needed are those for test of BFB
performance (Section 7.1) and for collection of mass spectra for storage
in spectral libraries (Section 7.2).
7. Calibration
7.1 Assemble the gas chromatographic apparatus and establish
operating conditions given in table 2. By injecting standards into the
GC, demonstrate that the analytical system meets the detection limits in
table 2 and the mass-intensity criteria in table 3 for 50 ng BFB.
7.2 Mass spectral libraries--detection and identification of the
compound of interest are dependent upon the spectra stored in user
created libraries.
7.2.1 Obtain a mass spectrum of each pollutant and labeled compound
and each internal standard by analyzing an authentic standard either
singly or as part of a mixture in which there is no interference between
closely eluted components. That only a single compound is present is
determined by examination of the spectrum. Fragments not attributable to
the compound under study indicate the presence of an interfering
compound. Adjust the analytical conditions and scan rate (for this test
only) to produce an undistorted spectrum at the GC peak maximum. An
undistorted spectrum will usually be obtained if five complete spectra
are collected across the upper half of the GC peak. Software algorithms
designed to ``enhance'' the spectrum may eliminate distortion, but may
also eliminate authentic m/z's or introduce other distortion.
7.2.3 The authentic reference spectrum is obtained under BFB tuning
conditions (Section 7.1 and table 3) to normalize it to spectra from
other instruments.
7.2.4 The spectrum is edited by saving the 5 most intense mass
spectral peaks and all other mass spectral peaks greater than 10 percent
of the base peak. This spectrum is stored for reverse search and for
compound confirmation.
7.3 Assemble the purge and trap device. Pack the trap as shown in
Figure 2 and condition overnight at 170-180 [deg]C by backflushing with
an inert gas at a flow rate of 20-30 mL/min. Condition traps daily for a
minimum of 10 minutes prior to use.
7.3.1 Analyze the aqueous performance standard (Section 6.7.2)
according to the purge and trap procedure in Section 10. Compute the
area at the primary m/z (table 4) for each compound. Compare these areas
to those obtained by injecting one [micro]L of the methanolic standard
(Section 6.7.3) to determine compound recovery. The recovery shall be
greater than 20 percent for the water soluble compounds, and 60-110
percent for all other compounds. This recovery is demonstrated initially
for each purge and trap GC/MS system. The test is repeated only if the
purge and trap or GC/MS systems are modified in any way that might
result in a change in recovery.
7.3.2 Demonstrate that 100 ng toluene (or toluene-d8) produces an
area at m/z 91 (or 99) approx one-tenth that required to exceed the
linear range of the system. The exact value must be determined by
experience for each instrument. It is used to match the calibration
range of the instrument to the analytical range and detection limits
required.
7.4 Calibration by isotope dilution--the isotope dilution approach
is used for the purgeable organic compounds when appropriate labeled
compounds are available and when interferences do not preclude the
analysis. If labeled compounds are not available, or interferences are
present, internal standard methods (Section 7.5 or 7.6) are used. A
calibration curve encompassing the concentration range of interest is
prepared for each compound determined. The relative response (RR) vs
concentration ([micro]g/L) is plotted or computed using a linear
regression. An example of a calibration curve for toluene using toluene-
d8 is given in figure 5. Also shown are the 10
percent error limits (dotted lines). Relative response is determined
according to the procedures described below. A minimum of five data
points are required for calibration (Section 7.4.4).
7.4.1 The relative response (RR) of pollutant to labeled compound is
determined from isotope ratio values calculated from acquired data.
Three isotope ratios are used in this process:
RX = the isotope ratio measured in the pure pollutant
(figure 6A).
Ry = the isotope ratio of pure labeled compound (figure
6B).
Rm = the isotope ratio measured in the analytical mixture
of the pollutant and labeled compounds (figure 6C).
The correct way to calculate RR is: RR = (Ry-
Rm) (RX + 1)/(Rm-
RX)(Ry + 1) If Rm is not between
2Ry and 0.5RX, the method does not apply and the
sample is analyzed by internal or external standard methods (Section 7.5
or 7.6).
7.4.2 In most cases, the retention times of the pollutant and
labeled compound are the same and isotope ratios (R's) can be calculated
from the EICP areas, where: R = (area at m1/z)/(area at
m2/z) If either of the areas is zero, it is assigned a value
of one in the calculations; that is, if: area of m1/z =
50721, and area of m2/z = 0, then R = 50721/1 = 50720. The m/
z's are always selected such that RXRy.
When there is a difference in retention times (RT) between the pollutant
and labeled compounds, special precautions are required to determine the
isotope ratios.
RX, Ry, and Rm are defined as
follows:
[[Page 353]]
RX=[area m1/z (at RT1)]/1
Ry = 1/[area m2/z (at RT2)]
Rm=[area m1/z (at RT1)]/[area
m2/z (at RT2)]
7.4.3 An example of the above calculations can be taken from the
data plotted in figure 6 for toluene and toluene-d8. For these data,
RX = 168920/1 = 168900, Ry = 1/60960 = 0.00001640,
and Rm = 96868/82508 = 1.174. The RR for the above data is
then calculated using the equation given in Section 7.4.1. For the
example, RR = 1.174.
Note: Not all labeled compounds elute before their pollutant
analogs.
7.4.4 To calibrate the analytical system by isotope dilution,
analyze a 5 mL aliquot of each of the aqueous calibration standards
(Section 6.7.1) spiked with an appropriate constant amount of the
labeled compound spiking solution (Section 6.6), using the purge and
trap procedure in section 10. Compute the RR at each concentration.
7.4.5 Linearity--if the ratio of relative response to concentration
for any compound is constant (less than 20 percent coefficient of
variation) over the 5 point calibration range, an averaged relative
response/concentration ratio may be used for that compound; otherwise,
the complete calibration curve for that compound shall be used over the
5 point calibration range.
7.5 Calibration by internal standard--used when criteria for isotope
dilution (Section 7.4) cannot be met. The method is applied to
pollutants having no labeled analog and to the labeled compounds. The
internal standards used for volatiles analyses are bromochloromethane,
2-bromo-1-chloropropane, and 1,4-dichlorobutane. Concentrations of the
labeled compounds and pollutants without labeled analogs are computed
relative to the nearest eluted internal standard, as shown in table 2.
7.5.1 Response factors--calibration requires the determination of
response factors (RF) which are defined by the following equation:
RF = (AsxCis)/(AisxCs),
where As is the EICP area at the characteristic m/z for the
compound in the daily standard. Ais is the EICP area at the
characteristic m/z for the internal standard.
Cis is the concentration (ug/L) of the internal standard
Cs is the concentration of the pollutant in the daily
standard.
7.5.2 The response factor is determined at 10, 20, 50, 100, and 200
ug/L for the pollutants (optionally at five times these concentrations
for gases and water soluble pollutants--see Section 6.7), in a way
analogous to that for calibration by isotope dilution (Section 7.4.4).
The RF is plotted against concentration for each compound in the
standard (Cs) to produce a calibration curve.
7.5.3 Linearity--if the response factor (RF) for any compound is
constant (less than 35 percent coefficient of variation) over the 5
point calibration range, an averaged response factor may be used for
that compound; otherwise, the complete calibration curve for that
compound shall be used over the 5 point range.
7.6 Combined calibration--by adding the isotopically labeled
compounds and internal standards (Section 6.6) to the aqueous
calibration standards (Section 6.7.1), a single set of analyses can be
used to produce calibration curves for the isotope dilution and internal
standard methods. These curves are verified each shift (Section 11.5) by
purging the aqueous performance standard (Section 6.7.2). Recalibration
is required only if calibration and on-going performance (Section 11.5)
criteria cannot be met.
8. Quality Assurance/Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality assurance program. The minimum requirements of this
program consist of an initial demonstration of laboratory capability,
analysis of samples spiked with labeled compounds to evaluate and
document data quality, and analysis of standards and blanks as tests of
continued performance. Laboratory performance is compared to established
performance criteria to determine if the results of analyses meet the
performance characteristics of the method.
8.1.1 The analyst shall make an initial demonstration of the ability
to generate acceptable accuracy and precision with this method. This
ability is established as described in Section 8.2.
8.1.2 The analyst is permitted to modify this method to improve
separations or lower the costs of measurements, provided all performance
specifications are met. Each time a modification is made to the method,
the analyst is required to repeat the procedure in Section 8.2 to
demonstrate method performance.
8.1.3 Analyses of blanks are required to demonstrate freedom from
contamination and that the compounds of interest and interfering
compounds have not been carried over from a previous analysis (Section
3). The procedures and criteria for analysis of a blank are described in
Sections 8.5 and 11.7.
8.1.4 The laboratory shall spike all samples with labeled compounds
to monitor method performance. This test is described in Section 8.3.
When results of these spikes indicate atypical method performance for
samples, the samples are diluted to bring method performance within
acceptable limits (Section 14.2).
8.1.5 The laboratory shall, on an on-going basis, demonstrate
through the analysis of the aqueous performance standard (Section 6.7.2)
that the analysis system is in control. This procedure is described in
Sections 11.1 and 11.5.
[[Page 354]]
8.1.6 The laboratory shall maintain records to define the quality of
data that is generated. Development of accuracy statements is described
in Sections 8.4 and 11.5.2.
8.2 Initial precision and accuracy--to establish the ability to
generate acceptable precision and accuracy, the analyst shall perform
the following operations:
8.2.1 Analyze two sets of four 5-mL aliquots (8 aliquots total) of
the aqueous performance standard (Section 6.7.2) according to the method
beginning in Section 10.
8.2.2 Using results of the first set of four analyses in Section
8.2.1, compute the average recovery (X) in [micro]g/L and the standard
deviation of the recovery (s) in [micro]g/L for each compound, by
isotope dilution for polluitants with a labeled analog, and by internal
standard for labeled compounds and pollutants with no labeled analog.
8.2.3 For each compound, compare s and X with the corresponding
limits for initial precision and accuracy found in table 5. If s and X
for all compounds meet the acceptance criteria, system performance is
acceptable and analysis of blanks and samples may begin. If individual X
falls outside the range for accuracy, system performance is unacceptable
for that compound.
Note: The large number of compounds in table 5 present a substantial
probability that one or more will fail one of the acceptance criteria
when all compoulds are analyzed. To determine if the analytical system
is out of control, or if the failure can be attributed to probability,
proceed as follows:
8.2.4 Using the results of the second set of four analyses, compute
s and X for only those compounds which failed the test of the first set
of four analyses (Section 8.2.3). If these compounds now pass, system
performance is acceptable for all compounds and analysis of blanks and
samples may begin. If, however, any of the same compounds fail again,
the analysis system is not performing properly for the compound(s) in
question. In this event, correct the problem and repeat the entire test
(Section 8.2.1).
8.3 The laboratory shall spike all samples with labeled compounds to
assess method performance on the sample matrix.
8.3.1 Spike and analyze each sample according to the method
beginning in Section 10.
8.3.2 Compute the percent recovery (P) of the labeled compounds
using the internal standard method (Section 7.5).
8.3.3 Compare the percent recovery for each compound with the
corresponding labeled compound recovery limit in table 5. If the
recovery of any compound falls outside its warning limit, method
performance is unacceptable for that compound in that sample. Therefore,
the sample matrix is complex and the sample is to be diluted and
reanalyzed, per Section 14.2.
8.4 As part of the QA program for the laboratory, method accuracy
for wastewater samples shall be assessed and records shall be
maintained. After the analysis of five wastewater samples for which the
labeled compounds pass the tests in Section 8.3.3, compute the average
percent recovery (P) and the standard deviation of the percent recovery
(sp) for the labeled compounds only. Express the accuracy
assessment as a percent recovery interval from P-2sp to P +
2sp. For example, if P = 90% and sp = 10%, the
accuracy interval is expressed as 70-110%. Update the accuracy
assessment for each compound on a regular basis (e.g. after each 5-10
new accuracy measurements).
8.5 Blanks--reagent water blanks are analyzed to demonstrate freedom
from carry-over (Section 3) and contamination.
8.5.1 The level at which the purge and trap system will carry
greater than 5 [micro]g/L of a pollutant of interest (table 1) into a
succeeding blank shall be determined by analyzing successively larger
concentrations of these compounds. When a sample contains this
concentration or more, a blank shall be analyzed immediately following
this sample to demonstrate no carry-over at the 5 [micro]g/L level.
8.5.2 With each sample lot (samples analyzed on the same 8 hr
shift), a blank shall be analyzed immediately after analysis of the
aqueous performance standard (Section 11.1) to demonstrate freedom from
contamination. If any of the compounds of interest (table 1) or any
potentially interfering compound is found in a blank at greater than 10
[micro]g/L (assuming a response factor of 1 relative to the nearest
eluted internal standard for compounds not listed in table 1), analysis
of samples is halted until the source of contamination is eliminated and
a blank shows no evidence of contamination at this level.
8.6 The specifications contained in this method can be met if the
apparatus used is calibrated properly, then maintained in a calibrated
state.
The standards used for calibration (Section 7), calibration
verification (Section 11.5) and for initial (Section 8.2) and on-going
(Section 11.5) precision and accuracy should be identical, so that the
most precise results will be obtained. The GC/MS instrument in
particular will provide the most reproducible results if dedicated to
the settings and conditions required for the analyses of volatiles by
this method.
8.7 Depending on specific program requirements, field replicates may
be collected to determine the precision of the sampling technique, and
spiked samples may be required to determine the accuracy of the analysis
when internal or external standard methods are used.
[[Page 355]]
9. Sample Collection, Preservation, and Handling
9.1 Grab samples are collected in glass containers having a total
volume greater than 20 mL. Fill sample bottles so that no air bubbles
pass through the sample as the bottle is filled. Seal each bottle so
that no air bubbles are entrapped. Maintain the hermetic seal on the
sample bottle until time of analysis.
9.2 Samples are maintained at 0-4 [deg]C from the time of collection
until analysis. If the sample contains residual chlorine, add sodium
thiosulfate preservative (10 mg/40 mL) to the empty sample bottles just
prior to shipment to the sample site. EPA Methods 330.4 and 330.5 may be
used for measurement of residual chlorine (Reference 8). If preservative
has been added, shake bottle vigorously for one minute immediately after
filling.
9.3 Experimental evidence indicates that some aromatic compounds,
notably benzene, toluene, and ethyl benzene are susceptible to rapid
biological degradation under certain environmental conditions.
Refrigeration alone may not be adequate to preserve these compounds in
wastewaters for more than seven days. For this reason, a separate sample
should be collected, acidified, and analyzed when these aromatics are to
be determined. Collect about 500 mL of sample in a clean container.
Adjust the pH of the sample to about 2 by adding HCl (1 + 1) while
stirring. Check pH with narrow range (1.4 to 2.8) pH paper. Fill a
sample container as described in Section 9.1. If residual chlorine is
present, add sodium thiosulfate to a separate sample container and fill
as in Section 9.1.
9.4 All samples shall be analyzed within 14 days of collection.
10. Purge, Trap, and GC/MS Analysis
10.1 Remove standards and samples from cold storage and bring to 20-
25 [deg].
10.2 Adjust the purge gas flow rate to 40 4
mL/min. Attach the trap inlet to the purging device and set the valve to
the purge mode (figure 3). Open the syringe valve located on the purging
device sample introduction needle (figure 1).
10.3 Remove the plunger from a 5-mL syringe and attach a closed
syringe valve. Open the sample bottle and carefully pour the sample into
the syringe barrel until it overflows. Replace the plunger and compress
the sample. Open the syringe valve and vent any residual air while
adjusting the sample volume to 5.0 mL. Because this process of taking an
aliquot destroys the validity of the sample for future analysis, fill a
second syringe at this time to protect against possible loss of data.
Add an appropriate amount of the labeled compound spiking solution
(Section 6.6) through the valve bore, then close the valve.
10.4 Attach the syringe valve assembly to the syringe valve on the
purging device. Open both syringe valves and inject the sample into the
purging chamber.
10.5 Close both valves and purge the sample for 11.0 0.1 minutes at 20-25 [deg]C.
10.6 After the 11 minute purge time, attach the trap to the
chromatograph and set the purge and trap apparatus to the desorb mode
(figure 4). Desorb the trapped compounds into the GC column by heating
the trap to 170-180 [deg]C while backflushing with carrier gas at 20-60
mL/min for four minutes. Start MS data acquisition upon start of the
desorb cycle, and start the GC column temperature program 3 minutes
later. Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are retention times and
detection limits that were achieved under these conditions. Other
columns may be used provided the requirements in Section 8 can be met.
If the priority pollutant gases produce GC peaks so broad that the
precision and recovery specifications (Section 8.2) cannot be met, the
column may be cooled to ambient or sub-ambient temperatures to sharpen
these peaks.
10.7 While analysis of the desorbed compounds proceeds, empty the
purging chamber using the sample introduction syringe. Wash the chamber
with two 5-mL portions of reagent water. After the purging device has
been emptied, allow the purge gas to vent through the chamber until the
frit is dry, so that it is ready for the next sample.
10.8 After desorbing the sample for four minutes, recondition the
trap by returning to the purge mode. Wait 15 seconds, then close the
syringe valve on the purging device to begin gas flow through the trap.
Maintain the trap temperature at 170-180 [deg]C. After approximately
seven minutes, turn off the trap heater and open the syringe valve to
stop the gas flow through the trap. When cool, the trap is ready for the
next sample.
11. System Performance
11.1 At the beginning of each 8 hr shift during which analyses are
performed, system calibration and performance shall be verified for all
pollutants and labeled compounds. For these tests, analysis of the
aqueous performance standard (Section 6.7.2) shall be used to verify all
performance criteria. Adjustment and/or recalibration (per Section 7)
shall be performed until all performance criteria are met. Only after
all performance criteria are met may blanks and samples be analyzed.
11.2 BFB spectrum validity--the criteria in table 3 shall be met.
11.3 Retention times--the absolute retention times of all compounds
shall approximate those given in Table 2.
[[Page 356]]
11.4 GC resolution--the valley height between toluene and toluene-d8
(at m/z 91 and 99 plotted on the same graph) shall be less than 10
percent of the taller of the two peaks.
11.5 Calibration verification and on-going precision and accuracy--
compute the concentration of each polutant (Table 1) by isotope dilution
(Section 7.4) for those compmunds which have labeled analogs. Compute
the concentration of each pollutant (Table 1) which has no labeled
analog by the internal standard method (Section 7.5). Compute the
concentration of the labeled compounds by the internal standard method.
These concentrations are computed based on the calibration data
determined in Section 7.
11.5.1 For each pollutant and labeled compound, compare the
concentration with the corresponding limit for on-going accuracy in
Table 5. If all compmunds meet the acceptance criteria, system
performance is acceptable and analysis of blanks and samples may
continue. If any individual value falls outside the range given, system
performance is unacceptable for that compound.
Note: The large number of compounds in Table 5 present a substantial
probability that one or more will fail the acceptance criteria when all
compounds are analyzed. To determine if the analytical system is out of
control, or if the failure may be attributed to probability, proceed as
follows:
11.5.1.1 Analyze a second aliquot of the aqueous performance
standard (Section 6.7.2).
11.5.1.2 Compute the concentration for only those compounds which
failed the first test (Section 11.5.1). If these compounds now pass,
system performance is acceptable for all compounds and analyses of
blanks and samples may proceed. If, however, any of the compounds fail
again, the measurement system is not performing properly for these
compounds. In this event, locate and correct the problem or recalibrate
the system (Section 7), and repeat the entire test (Section 11.1) for
all compounds.
11.5.2 Add results which pass the specification in 11.5.1.2 to
initial (Section 8.2) and previous on-going data. Update QC charts to
form a graphic representation of laboratory performance (Figure 7).
Develop a statement of accuracy for each pollutant and labeled compound
by calculating the average percentage recovery (R) and the standard
deviation of percent recovery (sr). Express the accuracy as a
recovery interval from R-2sr to R + 2sr. For
example, if R = 95% and sr = 5%, the accuracy is 85-105
percent.
12. Qualitative Determination--Accomplished by Comparison of Data from
Analysis of a Sample or Blank with Data from Analysis of the Shift
Standard (Section 11.1). Identification is Confirmed When Spectra and
Retention Times Agree Per the Criteria Below
12.1 Labeled compounds and pollutants having no labeled analog:
12.1.1 The signals for all characteristic masses stored in the
spectral library (Section 7.2.4) shall be present and shall maximize
within the same two consecutive scans.
12.1.2 Either (1) the background corrected EICP areas, or (2) the
corrected relative intensities of the mass spectral peaks at the GC peak
maximum shall agree within a factor of two (0.5 to 2 times) for all
masses stored in the library.
12.1.3 The retention time relative to the nearest eluted internal
standard shall be within 7 scans or 20 seconds, whichever is greater.
12.2 Pollutants having a labeled analog:
12.2.1 The signals for all characteristic masses stored in the
spectral library (Section 7.2.4) shall be present and shall maximize
within the same two consecutive scans.
12.2.2 Either (1) the background corrected EICP areas, or (2) the
corrected relative intensities of the mass spectral peaks at the GC peak
maximum shall agree within a factor of two for all masses stored in the
spectral library.
12.2.3 The retention time difference between the pollutant and its
labeled analog shall agree within 2 scans or
6 seconds (whichever is greater) of this
difference in the shift standard (Section 11.1).
12.3 Masses present in the experimental mass spectrum that are not
present in the reference mass spectrum shall be accounted for by
contaminant or background ions. If the experimental mass spectrum is
contaminated, an experienced spectrometrist (Section 1.4) is to
determine the presence or absence of the compound.
13. Quantitative Determination
13.1 Isotope dilution--by adding a known amount of a labeled
compound to every sample prior to purging, correction for recovery of
the pollutant can be made because the pollutant and its labeled analog
exhibit the same effects upon purging, desorption, and gas
chromatography. Relative response (RR) values for sample mixtures are
used in conjunction with calibration curves described in Section 7.4 to
determine concentrations directly, so long as labeled compound spiking
levels are constant. For the toluene example given in Figure 6 (Section
7.4.3), RR would be equal to 1.174. For this RR value, the toluene
calibration curve given in Figure 5 indicates a concentration of 31.8
[micro]g/L.
[[Page 357]]
13.2 Internal standard--calculate the concentration using the
response factor determined from calibration data (Section 7.5) and the
following equation:
Concentration = (As x Cis)/(Ais x
RF) where the terms are as defined in Section 7.5.1.
13.3 If the EICP area at the quantitation mass for any compound
exceeds the calibration range of the system, the sample is diluted by
successive factors of 10 and these dilutions are analyzed until the area
is within the calibration range.
13.4 Report results for all pollutants and labeled compounds (Table
1) found in all standards, blanks, and samples, in [micro]g/L to three
significant figures. Results for samples which have been diluted are
reported at the least dilute level at which the area at the quantitation
mass is within the calibration range (Section 13.3) and the labeled
compound recovery is within the normal range for the Method (Section
14.2).
14. Analysis of Complex Samples
14.1 Untreated effluents and other samples frequently contain high
levels (1000 [micro]g/L) of the compounds of interest and of
interfering compounds. Some samples will foam excessively when purged;
others will overload the trap/or GC column.
14.2 Dilute 0.5 mL of sample with 4.5 mL of reagent water and
analyze this diluted sample when labeled compound recovery is outside
the range given in Table 5. If the recovery remains outside of the range
for this diluted sample, the aqueous performance standard shall be
analyzed (Section 11) and calibration verified (Section 11.5). If the
recovery for the labeled compmund in the aqueous performance standard is
outside the range given in Table 5, the analytical system is out of
control. In this case, the instrumelt shall be repaired, the performance
specifications in Section 11 shall be met, and the analysis of the
undiluted sample shall be repeated. If the recovery for the aqueous
performance standard is within the range given in Table 5, the method
does not work on the sample being analyzed and the result may not be
reported for regulatory compliance purposes.
14.3 Reverse search computer programs can misinterpret the spectrum
of chromatographically unresolved pollutant and labeled compound pairs
with overlapping spectra when a high level of the pollutant is present.
Examine each chromatogram for peaks greater than the height of the
internal standard peaks. These peaks can obscure the compounds of
interest.
15. Method Performance
15.1 The specifications for this method were taken from the inter-
laboratory validation of EPA Method 624 (reference 9). Method 1624 has
been shown to yield slightly better performance on treated effluents
than Method 624. Additional method performance data can be found in
Reference 10.
References
1. ``Performance Tests for the Evaluation of Computerized Gas
Chromatography/Mass Spectrometry Equipment and Laboratories,'' USEPA,
EMSL/Cincinnati, OH 45268, EPA-600/4-80-025 (April 1980).
2. Bellar, T.A. and Lichtenberg, J.J., ``Journal American Water
Works Association,'' 66, 739 (1974).
3. Bellar, T.A. and Lichtenberg, J.J., ``Semi-automated Headspace
Analysis of Drinking Waters and Industrial Waters for Purgeable Volatile
Organic Compounds,'' in Measurement of Organic Pollutants Water and
Wastewater, C.E. VanHall, ed., American Society for Testing Materials,
Philadelphia, PA, Special Technical Publication 686, (1978).
4. ``Working with Carcinogens,'' DHEW, PHS, NIOSH, Publication 77-
206 (1977).
5. ``OSHA Safety and Health Standards, General Industry,'' 29 CFR
part 1910, OSHA 2206, (1976).
6. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety (1979).
7. ``Handbook of Analytical Quality Control in Water and Wastewater
Laboratories,'' USEPA, EMSL/Cincinnati, OH 45268, EPA-4-79-019 (March
1979).
8. ``Methods 330.4 and 330.5 for Total Residual Chlorine,'' USEPA,
EMSL/Cincinnati, OH 45268, EPA-4-79-020 (March 1979).
9. ``EPA Method Study 29 EPA Method 624--Purgeables,'' EPA 600/4-84-
054, National Technical Information Service, PB84-209915, Springfield,
Virginia 22161, June 1984.
10. ``Colby, B.N., Beimer, R.G., Rushneck, D.R., and Telliard, W.A.,
``Isotope Dilution Gas Chromatography-Mass Spectrometry for the
Determination of Priority Pollutants in Industrial Effluents,'' USEPA,
Effluent Guidelines Division, Washington, DC 20460 (1980).
Table 1--Volatile Organic Compounds Analyzed by Isotope Dilution Gc/MS
------------------------------------------------------------------------
CAS
Compound Storet registry EPA-EGD NPDES
------------------------------------------------------------------------
Acetone...................... 81552 67-64-1 516 V
Acrolein..................... 34210 107-02-8 002 V 001 V
Acrylonitrile................ 34215 107-13-1 003 V 002 V
Benzene...................... 34030 71-43-2 004 V 003 V
Bromodichloromethane......... 32101 75-27-4 048 V 012 V
[[Page 358]]
Bromoform.................... 32104 75-25-2 047 V 005 V
Bromomethane................. 34413 74-83-9 046 V 020 V
Carbon tetrachloride......... 32102 56-23-5 006 V 006 V
Chlorobenzene................ 34301 108-90-7 007 V 007 V
Chloroethane................. 34311 75-00-3 016 V 009 V
2-chloroethylvinyl ether..... 34576 110-75-8 019 V 010 V
Chloroform................... 32106 67-66-1 023 V 011 V
Chloromethane................ 34418 74-87-3 045 V 021 V
Dibromochloromethane......... 32105 124-48-1 051 V 008 V
1,1-dichloroethane........... 34496 75-34-3 013 V 014 V
1,2-dichloroethane........... 34536 107-06-2 010 V 015 V
1,1-dichloroethene........... 34501 75-35-4 029 V 016 V
Trans-1,2-dichloroethane..... 34546 156-60-5 030 V 026 V
1,2-dichloropropane.......... 34541 78-87-5 032 V 017 V
Cis-1,3-dichloropropene...... 34704 10061-01-5
Trans-1,3-dichloropropene.... 34699 10061-02-6 033 V
Diethyl ether................ 81576 60-29-7 515 V
P-dioxane.................... 81582 123-91-1 527 V
Ethylbenzene................. 34371 100-41-4 038 V 019 V
Methylene chloride........... 34423 75-09-2 044 V 022 V
Methyl ethyl ketone.......... 81595 78-93-3 514 V
1,1,2,2-tetrachloroethane.... 34516 79-34-5 015 V 023 V
Tetrachlorethene............. 34475 127-18-4 085 V 024 V
Toluene...................... 34010 108-88-3 086 V 025 V
1,1,1-trichloroethane........ 34506 71-55-6 011 V 027 V
1,1,2-trichloroethane........ 34511 79-00-5 014 V 028 V
Trichloroethene.............. 39180 79-01-6 087 V 029 V
Vinyl chloride............... 39175 75-01-4 088 V 031 V
------------------------------------------------------------------------
Table 2--Gas Chromatography of Purgeable Organic Compounds by Isotope
Dilution GC/MS
------------------------------------------------------------------------
Mean Minimum
EGD Ref retention level (2)
No. Compound EGD time ([micro]g/
(1) No. (sec) L)
------------------------------------------------------------------------
181 Bromochloromethane (I.S.).............. 181 730 10
245 Chloromethane-d3....................... 181 147 50
345 Chloromethane.......................... 245 148 50
246 Bromomethane-d3........................ 181 243 50
346 Bromomethane........................... 246 246 50
288 Vinyl chloride-d3...................... 181 301 50
388 Vinyl chloride......................... 288 304 10
216 Chloroethane-d5........................ 181 378 50
316 Chloroethane........................... 216 386 50
244 Methylene chloride-d2.................. 181 512 10
344 Methylene chloride..................... 244 517 10
616 Acetone-d6............................. 181 554 50
716 Acetone................................ 616 565 50
002 Acrolein............................... 181 566 50
203 Acrylonitrile-d3....................... 181 606 50
303 Acrylonitrile.......................... 203 612 50
229 1,1-dichloroethene-d2.................. 181 696 10
329 1,1-dichloroethene..................... 229 696 10
213 1,1-dichloroethane-d3.................. 181 778 10
313 1,1-dichloroethane..................... 213 786 10
615 Diethyl ether-d10...................... 181 804 50
715 Diethyl ether.......................... 615 820 50
230 Trans-1,2-dichloroethene-d2............ 181 821 10
330 Trans-1,2-dichloroethene............... 230 821 10
614 Methyl ethyl ketone-d3................. 181 840 50
714 Methyl ethyl ketone.................... 614 848 50
223 Chloroform-13C1........................ 181 861 10
323 Chloroform............................. 223 861 10
210 1,2-dichloroethane-d4.................. 181 901 10
310 1,2-dichloroethane..................... 210 910 10
211 1,1,1-trichloroethane-13C2............. 181 989 10
311 1,1,1-trichloroethane.................. 211 999 10
527 p-dioxane.............................. 181 1001 10
206 Carbon tetrachloride-13C1.............. 182 1018 10
306 Carbon tetrachloride................... 206 1018 10
248 Bromodichloromethane-13C1.............. 182 1045 10
348 Bromodichloromethane................... 248 1045 10
232 1,2-dichloropropane-d6................. 182 1123 10
332 1.2-dichloropropane.................... 232 1134 10
233 Trans-1,3-dichloropropene-d4........... 182 1138 10
333 Trans-1,3-dichloropropene.............. 233 1138 10
287 Trichloroethene-13C1................... 182 1172 10
387 Trichloroethene........................ 287 1187 10
204 Benzene-d6............................. 182 1200 10
304 Benzene................................ 204 1212 10
251 Chlorodibromemethane-13C1.............. 182 1222 10
351 Chlorodibromomethane................... 251 1222 10
214 1,1,2-trichloroethane-13C2............. 182 1224 10
314 1,1,2-trichloroethane.................. 214 1224 10
019 2-chloroethylvinyl ether............... 182 1278 10
182 2-bromo-1-chloropropane (I.S.)......... 182 1306 10
247 Bromoform-13C1......................... 182 1386 10
347 Bromoform.............................. 247 1386 10
215 1,1,2,2-tetrachloroethane-d2........... 183 1525 10
315 1,1,2,2-tetrachloroethane.............. 215 1525 10
285 Tetrachloroethene-13C2................. 183 1528 10
385 Tetrachloroethene...................... 285 1528 10
183 1,4-dichlorobutale (int std)........... 183 1555 10
286 Toluene-d8............................. 183 1603 10
386 Toluene................................ 286 1619 10
[[Page 359]]
207 Chlorobenzene-d5....................... 183 1679 10
307 Chlorobenzene.......................... 207 1679 10
238 Ethylbenzene-d10....................... 183 1802 10
338 Ethylbenzene........................... 238 1820 10
185 Bromofluorobenzene..................... 183 1985 10
------------------------------------------------------------------------
(1) Reference numbers beginning with 0, 1 or 5 indicate a pollutant
quantified by the internal standard method; reference numbers
beginning with 2 or 6 indicate a labeled compound quantified by the
internal standard method; reference numbers beginning with 3 or 7
indicate a pollutant quantified by isotope dilution.
(2) This is a minimum level at which the analytical system shall give
recognizable mass spectra (background corrected) and acceptable
calibration points. Column: 2.4m (8 ft) x 2 mm i.d. glass, packed with
one percent SP-1000 coated on 60/80 Carbopak B. Carrier gas: helium at
40 mL/min. Temperature program: 3 min at 45 [deg]C, 8 [deg]C per min
to 240 [deg]C, hold at 240 [deg]C for 15 minutes.
Note: The specifications in this table were developed from data
collected from three wastewater laboratories.
Table 3--BFB Mass-Intensity Specifications
------------------------------------------------------------------------
Mass Intensity required
------------------------------------------------------------------------
50 15 to 40 percent of mass 95.
75 30 to 60 percent of mass 95.
95 base peak, 100 percent.
96 5 to 9 percent of mass 95.
173 <2 percent of mass 174.
174 50 percent of mass 95.
175 5 to 9 percent of mass 174
176 95 to 101 percent of mass 174
177 5 to 9 percent of mass 176.
------------------------------------------------------------------------
Table 4--Volatile Organic Compound Characteristic Masses
------------------------------------------------------------------------
Primary m/
Labeled compound Analog z's
------------------------------------------------------------------------
Acetone............................................ d6 58/64
Acrolein........................................... d2 56/58
Acrylonitrile...................................... d3 53/56
Benzene............................................ d6 78/84
Bromodichloromethane............................... 13C 83/86
Bromoform.......................................... 13C 173/176
Bromomethale....................................... d3 96/99
Carbon tetrachloride............................... 13C 47/48
Chlorobenzene...................................... d5 112/117
Chloroethane....................................... d5 64/71
2-chloroethylvinyl ether........................... d7 106/113
Chloroform......................................... 13C 85/86
Chloromethane...................................... d3 50/53
Dibromochloromethane............................... 13C 129/130
1,1-dichloroethane................................. d3 63/66
1,2-dichloroethane................................. d4 62/67
1,1-dichloroethene................................. d2 61/65
Trans-1,2-dichloroethene........................... d2 61/65
1,2-dichloropropane................................ d6 63/67
Cis-1,3-dichloropropene............................ d4 75/79
Trans-1,3-dichloropropene.......................... d4 75/79
Diethyl ether...................................... d10 74/84
p-dioxane.......................................... d8 88/96
Ethylbenzene....................................... d10 106/116
Methylene chloride................................. d2 84/88
Methyl ethyl ketone................................ d3 72/75
1,1,2,2-tetrachloroethane.......................... d2 83/84
Tetrachloroethene.................................. 13C2 166/172
Toluene............................................ d8 92/99
1,1,1-trichloroethane.............................. d3 97/102
1,1,2-trichloroethane.............................. 13C2 83/84
Trichloroethene.................................... 13C 95/133
Vinyl chloride..................................... d3 62/65
------------------------------------------------------------------------
Table 5--Acceptance Criteria for Performance Tests
----------------------------------------------------------------------------------------------------------------
Acceptance criteria at 20 [micro]g/L
------------------------------------------------------
Initial precision and Labeled On-going
accuracy section 8.2.3 compound accuracy
Compound ----------------------------- recovery sec. 11.5
sec. 8.3 ------------
s ([micro]g/ and 14.2
L) X ([micro]g/L) ------------- R ([micro]g/
P (percent) L)
----------------------------------------------------------------------------------------------------------------
Acetone.................................................. Note 1
Acrolein................................................. Note 2
Acrylonitrile............................................ Note 2
Benzene.................................................. 9.0 13.0-28.2 ns-196 4-33
Bromodichloromethane..................................... 8.2 6.5-31.5 ns-199 4-34
Bromoform................................................ 7.0 7.4-35.1 ns-214 6-36
Bromomethane............................................. 25.0 d-54.3 ns-414 d-61
Carbon tetrachloride..................................... 6.9 15.9-24.8 42-165 12-30
Chlorobenzene............................................ 8.2 14.2-29.6 ns-205 4-35
Chloroethane............................................. 14.8 2.1-46.7 ns-308 d-51
2-chloroethylvinyl ether................................. 36.0 d-69.8 ns-554 d-79
Chloroform............................................... 7.9 11.6-26.3 18-172 8-30
Chloromethane............................................ 26.0 d-55.5 ns-410 d-64
Dibromochloromethane..................................... 7.9 11.2-29.1 16-185 8-32
1,1-dichloroethane....................................... 6.7 11.4-31.4 23-191 9-33
1,2-dichloroethane....................................... 7.7 11.6-30.1 12-192 8-33
1,1-dichloroethene....................................... 11.7 d-49.8 ns-315 d-52
Trans-1,2-dichloroethene................................. 7.4 10.5-31.5 15-195 8-34
[[Page 360]]
1,2-dichloropropane...................................... 19.2 d-46.8 ns-343 d-51
Cis-1,3-dichloropropene.................................. 22.1 d-51.0 ns-381 d-56
Trans-1,3-dichloropropene................................ 14.5 d-40.2 ns-284 d-44
Diethyl ether............................................ Note 1
P-dioxane................................................ Note 1
Ethyl benzene............................................ 9.6 15.6-28.5 ns-203 5-35
Methylene chloride....................................... 9.7 d-49.8 ns-316 d-50
Methyl ethyl ketone...................................... Note 1
1,1,2,2-tetrachloroethane................................ 9.6 10.7-30.0 5-199 7-34
Tetrachloroethene........................................ 6.6 15.1-28.5 31-181 11-32
Toluene.................................................. 6.3 14.5-28.7 4-193 6-33
1,1,1-trichloroethane.................................... 5.9 10.5-33.4 12-200 8-35
1,1,2-trichloroethane.................................... 7.1 11.8-29.7 21-184 9-32
Trichloroethene.......................................... 8.9 16.6-29.5 35-196 12-34
Vinyl chloride........................................... 27.9 d-58.5 ns-452 d-65
----------------------------------------------------------------------------------------------------------------
d = detected; result must be greater than zero.
ns = no specification; limit would be below detection limit.
Specifications not available for these compounds at time of release of this method.
Specifications not developed for these compounds; use method 603.
[[Page 361]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.055
[[Page 362]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.056
Method 1625 Revision B--Semivolatile Organic Compounds by Isotope
Dilution GC/MS
1. Scope and Application
1.1 This method is designed to determine the semivolatile toxic
organic pollutants associated with the 1976 Consent Decree and
additional compounds amenable to extraction and analysis by capillary
column gas chromatography-mass spectrometry (GC/MS).
1.2 The chemical compounds listed in Tables 1 and 2 may be
determined in municipal and industrial discharges by this method. The
method is designed to meet the survey
[[Page 363]]
requirements of Effluent Guidelines Division (EGD) and the National
Pollutants Discharge Elimination System (NPDES) under 40 CFR 136.1. Any
modifications of this method, beyond those expressly permitted, shall be
considered as major modifications subject to application and approval of
alternate test procedures under 40 CFR 136.4 and 136.5.
1.3 The detection limit of this method is usually dependent on the
level of interferences rather than instrumental limitations. The limits
listed in Tables 3 and 4 represent the minimum quantity that can be
detected with no interferences present.
1.4 The GC/MS portions of this method are for use only by analysts
experienced with GC/MS or under the close supervision of such qualified
persons. Laboratories unfamiliar with analyses of environmental samples
by GC/MS should run the performance tests in reference 1 before
beginning.
2. Summary of Method
2.1 Stable isotopically labeled analogs of the compounds of interest
are added to a one liter wastewater sample. The sample is extracted at
pH 12-13, then at pH <2 with methylene chloride using continuous
extraction techniques. The extract is dried over sodium sulfate and
concentrated to a volume of one mL. An internal standard is added to the
extract, and the extract is injected into the gas chromatograph (GC).
The compounds are separated by GC and detected by a mass spectrometer
(MS). The labeled compounds serve to correct the variability of the
analytical technique.
2.2 Identification of a compound (qualitative analysis) is performed
by comparing the GC retention time and background corrected
characteristic spectral masses with those of authentic standards.
2.3 Quantitative analysis is performed by GC/MS using extracted ion
current profile (EICP) areas. Isotope dilution is used when labeled
compounds are available; otherwise, an internal standard method is used.
2.4 Quality is assured through reproducible calibration and testing
of the extraction and GC/MS systems.
3. Contamination and Interferences
3.1 Solvents, reagents, glassware, and other sample processing
hardware may yield artifacts and/or elevated baselines causing
misinterpretation of chromatograms and spectra. All materials shall be
demonstrated to be free from interferences under the conditions of
analysis by running method blanks initially and with each sample lot
(samples started through the extraction process on a given 8 hr shift,
to a maximum of 20). Specific selection of reagents and purification of
solvents by distillation in all-glass systems may be required. Glassware
and, where possible, reagents are cleaned by solvent rinse and baking at
450 [deg]C for one hour minimum.
3.2 Interferences coextracted from samples will vary considerably
from source to source, depending on the diversity of the industrial
complex or municipality being samples.
4. Safety
4.1 The toxicity or carcinogenicity of each compound or reagent used
in this method has not been precisely determined; however, each chemical
compound should be treated as a potential health hazard. Exposure to
these compounds should be reduced to the lowest possible level. The
laboratory is responsible for maintaining a current awareness file of
OSHA regulations regarding the safe handling of the chemicals specified
in this method. A reference file of data handling sheets should also be
made available to all personnel involved in these analyses. Additional
information on laboratory safety can be found in references 2-4.
4.2 The following compounds covered by this method have been
tentatively classified as known or suspected human or mammalian
carcinogens: benzidine benzo(a)anthracene, 3,3'-dichlorobenzidine,
benzo(a)pyrene, dibenzo(a,h)anthracene, N-nitrosodimethylamine, and
[beta]-naphtylamine. Primary standards of these compounds shall be
prepared in a hood, and a NIOSH/MESA approved toxic gas respirator
should be worn when high concentrations are handled.
5. Apparatus and Materials
5.1 Sampling equipment for discrete or composite sampling.
5.1.1 Sample bottle, amber glass, 1.1 liters minimum. If amber
bottles are not available, samples shall be protected from light.
Bottles are detergent water washed, then solvent rinsed or baked at 450
[deg]C for one hour minimum before use.
5.1.2 Bottle caps--threaded to fit sample bottles. Caps are lined
with Teflon. Aluminum foil may be substituted if the sample is not
corrosive. Liners are detergent water washed, then reagent water
(Section 6.5) and solvent rinsed, and baked at approximately 200 [deg]C
for one hour minimum before use.
5.1.3 Compositing equipment--automatic or manual compositing system
incorporating glass containers for collection of a minimum 1.1 liters.
Sample containers are kept at 0 to 4 [deg]C during sampling. Glass or
Teflon tubing only shall be used. If the sampler uses a peristaltic
pump, a minimum length of compressible silicone rubber tubing may be
used in the pump only. Before use, the tubing is thoroughly rinsed with
methanol, followed by repeated rinsings with reagent water (Section 6.5)
to minimize sample contamination. An integrating flow meter is used to
collect proportional composite samples.
[[Page 364]]
5.2 Continuous liquid-liquid extractor--Teflon or glass conncecting
joints and stopcocks without lubrication (Hershberg-Wolf Extractor) one
liter capacity, Ace Glass 6841-10, or equivalent.
5.3 Drying column--15 to 20 mm i.d. Pyrex chromatographic column
equipped with coarse glass frit or glass wool plug.
5.4 Kuderna-Danish (K-D) apparatus
5.4.1 Concentrator tube--10mL, graduated (Kontes K-570050-1025, or
equivalent) with calibration verified. Ground glass stopper (size 19/22
joint) is used to prevent evaporation of extracts.
5.4.2 Evaporation flask--500 mL (Kontes K-570001-0500, or
equivalent), attached to concentrator tube with springs (Kontes K-
662750-0012).
5.4.3 Snyder column--three ball macro (Kontes K-503000-0232, or
equivalent).
5.4.4 Snyder column--two ball micro (Kontes K-469002-0219, or
equivalent).
5.4.5 Boiling chips--approx 10/40 mesh, extracted with methylene
chloride and baked at 450 [deg]C for one hr minimum.
5.5 Water bath--heated, with concentric ring cover, capable of
temperature control 2 [deg]C, installed in a fume
hood.
5.6 Sample vials--amber glass, 2-5 mL with Teflon-lined screw cap.
5.7 Analytical balance--capable of weighing 0.1 mg.
5.8 Gas chromatograph--shall have splitless or on-column injection
port for capillary column, temperature program with 30 [deg]C hold, and
shall meet all of the performance specifications in Section 12.
5.8.1 Column--30 5 m x 0.25 0.02 mm i.d. 5% phenyl, 94% methyl, 1% vinyl silicone
bonded phase fused silica capillary column (J & W DB-5, or equivalent).
5.9 Mass spectrometer--70 eV electron impact ionization, shall
repetitively scan from 35 to 450 amu in 0.95 to 1.00 second, and shall
produce a unit resolution (valleys between m/z 441-442 less than 10
percent of the height of the 441 peak), backgound corrected mass
spectrum from 50 ng decafluorotriphenylphosphine (DFTPP) introduced
through the GC inlet. The spectrum shall meet the mass-intensity
criteria in Table 5 (reference 5). The mass spectrometer shall be
interfaced to the GC such that the end of the capillary column
terminates within one centimeter of the ion source but does not
intercept the electron or ion beams. All portions of the column which
connect the GC to the ion source shall remain at or above the column
temperature during analysis to preclude condensation of less volatile
compounds.
5.10 Data system--shall collect and record MS data, store mass-
intensity data in spectral libraries, process GC/MS data, generate
reports, and shall compute and record response factors.
5.10.1 Data acquisition--mass spectra shall be collected
continuously throughout the analysis and stored on a mass storage
device.
5.10.2 Mass spectral libraries--user created libraries containing
mass spectra obtained from analysis of authentic standards shall be
employed to reverse search GC/MS runs for the compounds of interest
(Section 7.2).
5.10.3 Data processing--the data system shall be used to search,
locate, identify, and quantify the compounds of interest in each GC/MS
analysis. Software routines shall be employed to compute retention times
and peak areas. Displays of spectra, mass chromatograms, and library
comparisons are required to verify results.
5.10.4 Response factors and multipoint calibrations--the data system
shall be used to record and maintain lists of response factors (response
ratios for isotope dilution) and multipoint calibration curves (Section
7). Computations of relative standard deviation (coefficient of
variation) are useful for testing calibration linearity. Statistics on
initial (Section 8.2) and on-going (Section 12.7) performance shall be
computed and maintained.
6. Reagents and Standards
6.1 Sodium hydroxide--reagent grade, 6N in reagent water.
6.2 Sulfuric acid--reagent grade, 6N in reagent water.
6.3 Sodium sulfate--reagent grade, granular anhydrous, rinsed with
methylene chloride (20 mL/g) and conditioned at 450 [deg]C for one hour
minimum.
6.4 Methylene chloride--distilled in glass (Burdick and Jackson, or
equivalent).
6.5 Reagent water--water in which the compounds of interest and
interfering compounds are not detected by this method.
6.6 Standard solutions--purchased as solutions or mixtures with
certification to their purity, concentration, and authenticity, or
prepared from materials of known purity and composition. If compound
purity is 96 percent or greater, the weight may be used without
correction to compute the concentration of the standard. When not being
used, standards are stored in the dark at -20 to -10 [deg]C in screw-
capped vials with Teflon-lined lids. A mark is placed on the vial at the
level of the solution so that solvent evaporation loss can be detected.
The vials are brought to room temperature prior to use. Any precipitate
is redissolved and solvent is added if solvent loss has occurred.
6.7 Preparation of stock solutions--prepare in methylene chloride,
benzene, p-dioxane, or a mixture of these solvents per the steps below.
Observe the safety precautions in Section 4. The large number of labeled
and unlabeled acid, base/neutral, and Appendix C compounds used for
combined
[[Page 365]]
calibration (Section 7) and calibration verification (12.5) require high
concentratimns (approx 40 mg/mL) when individual stock solutions are
prepared, so that dilutions of mixtures will permit calibration with all
compounds in a single set of solutions. The working range for most
compounds is 10-200 [micro]g/mL. Compounds with a reduced MS response
may be prepared at higher concentrations.
6.7.1 Dissolve an appropriate amount of assayed reference material
in a suitable solvent. For example, weigh 400 mg naphthalene in a 10 mL
ground glass stoppered volumetric flask and fill to the mark with
benzene. After the naphthalene is completely dissolved, transfer the
solution to a 15 mL vial with Teflon-lined cap.
6.7.2 Stock standard solutions should be checked for signs of
degradation prior to the preparation of calibration or performance test
standards. Quality control check samples that can be used to determine
the accuracy of calibration standards are available from the US
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268.
6.7.3 Stock standard solutions shall be replaced after six months,
or sooner if comparison with quality control check samples indicates a
change in concentration.
6.8 Labeled compound spiking solution--from stock standard solutions
prepared as above, or from mixtures, prepare the spiking solution at a
concentration of 200 [micro]g/mL, or at a concentration appropriate to
the MS response of each compound.
6.9 Secondary standard--using stock solutions (Section 6.7), prepare
a secondary standard containing all of the compounds in Tables 1 and 2
at a concentration of 400 [micro]g/mL, or higher concentration
appropriate to the MS response of the compound.
6.10 Internal standard solution--prepare 2,2'-difluorobiphenyl (DFB)
at a concentration of 10 mg/mL in benzene.
6.11 DFTPP solution--prepare at 50 [micro]g/mL in acetone.
6.12 Solutions for obtaining authentic mass spectra (Section 7.2)--
prepare mixtures of compounds at concentrations which will assure
authentic spectra are obtained for storage in libraries.
6.13 Calibration solutions--combine 0.5 mL of the solution in
Section 6.8 with 25, 50, 125, 250, and 500 uL of the solution in section
6.9 and bring to 1.00 mL total volume each. This will produce
calibration solutions of nominal 10, 20, 50, 100, and 200 [micro]g/mL of
the pollutants and a constant nominal 100 [micro]g/mL of the labeled
compounds. Spike each solution with 10 [micro]L of the internal standard
solution (Section 6.10). These solutions permit the relative response
(labeled to unlabeled) to be measured as a function of concentration
(Section 7.4).
6.14 Precision and recovery standard--used for determination of
initial (Section 8.2) and on-going (Section 12.7) precision and
recovery. This solution shall contain the pollutants and labeled
compounds at a nominal concentration of 100 [micro]g/mL.
6.15 Stability of solutions--all standard solutions (Sections 6.8-
6.14) shall be analyzed within 48 hours of preparation and on a monthly
basis thereafter for signs of degradation. Standards will remain
acceptable if the peak area at the quantitation mass relative to the DFB
internal standard remains within 15 percent of the
area obtained in the initial analysis of the standard.
7. Calibration
7.1 Assemble the GC/MS and establish the operating conditions in
Table 3. Analyze standards per the procedure in Section 11 to
demonstrate that the analytical system meets the detection limits in
Tables 3 and 4, and the mass-intensity criteria in Table 5 for 50 ng
DFTPP.
7.2 Mass spectral libraries--detection and identification of
compounds of interest are dependent upon spectra stored in user created
libraries.
7.2.1 Obtain a mass spectrum of each pollutant, labeled compound,
and the internal standard by analyzing an authentic standard either
singly or as part of a mixture in which there is no interference between
closely eluted components. That only a single compound is present is
determined by examination of the spectrum. Fragments not attributable to
the compound under study indicate the presence of an interfering
compound.
7.2.2 Adjust the analytical conditions and scan rate (for this test
only) to produce an undistorted spectrum at the GC peak maximum. An
undistorted spectrum will usually be obtained if five complete spectra
are collected across the upper half of the GC peak. Software algorithms
designed to ``enhance'' the spectrum may eliminate distortion, but may
also eliminate authentic masses or introduce other distortion.
7.2.3 The authentic reference spectrum is obtained under DFTPP
tuning conditions (Section 7.1 and Table 5) to normalize it to spectra
from other instruments.
7.2.4 The spectrum is edited by saving the 5 most intense mass
spectral peaks and all other mass spectral peaks greater than 10 percent
of the base peak. This edited spectrum is stored for reverse search and
for compound confirmation.
7.3 Analytical range--demonstrate that 20 ng anthracene or
phenanthrene produces an area at m/z 178 approx one-tenth that required
to exceed the linear range of the system. The exact value must be
determined by experience for each instrument. It is used to match the
calibration range of the instrument to the analytical range and
detection limits required, and to diagnose instrument
[[Page 366]]
sensitivity problems (Section 15.4). The 20 ug/mL calibration standard
(Section 6.13) can be used to demonstrate this performance.
7.3.1 Polar compound detection--demonstrate that unlabeled
pentachlorophenol and benzidine are detectable at the 50 [micro]g/mL
level (per all criteria in Section 13). The 50 [micro]g/mL calibration
standard (Section 6.13) can be used to demonstrate this performance.
7.4 Calibration with isotope dilution--isotope dilution is used when
(1) labeled compounds are available, (2) interferences do not preclude
its use, and (3) the quantitation mass extracted ion current profile
(EICP) area for the compound is in the calibration range. If any of
these conditions preclude isotope dilution, internal standard methods
(Section 7.5 or 7.6) are used.
7.4.1 A calibration curve encompassing the concentration range is
prepared for each compound to be determined. The relative response
(pollutant to labeled) vs concentration in standard solutions is plotted
or computed using a linear regression. The example in Figure 1 shows a
calibration curve for phenol using phenol-d5 as the isotopic diluent.
Also shown are the 10 percent error limits (dotted
lines). Relative Reponse (RR) is determined according to the procedures
described below. A minimum of five data points are employed for
calibration.
7.4.2 The relative response of a pollutant to its labeled analog is
determined from isotope ratio values computed from acquired data. Three
isotope ratios are used in this process:
RX = the isotope ratio measured for the pure pollutant.
Ry = the isotope ratio measured for the labeled compound.
Rm = the isotope ratio of an analytical mixture of
pollutant and labeled compounds.
The m/z's are selected such that
RXRy. If Rm is not between
2Ry and 0.5RX, the method does not apply and the
sample is analyzed by internal or external standard methods.
7.4.3 Capillary columns usually separate the pollutant-labeled pair,
with the labeled compound eluted first (Figure 2). For this case,
RX = [area m1/z]/1, at the retention time of the
pollutant (RT2). Ry = 1/[area m2/z, at
the retention time of the labeled compound RT1).
Rm = [area at m1/z (at RT2)]/[area at
RT1)], as measured in the mixture of the pollutant and
labeled compounds (Figure 2), and RR = Rm.
7.4.4 Special precautions are taken when the pollutant-labeled pair
is not separated, or when another labeled compound with interfering
spectral masses overlaps the pollutant (a case which can occur with
isomeric compounds). In this case, it is necessary to determine the
respective contributions of the pollutant and labeled compounds to the
respective EICP areas. If the peaks are separated well enough to permit
the data system or operator to remove the contributions of the compounds
to each other, the equations in Section 7.4.3 apply. This usually occurs
when the height of the valley between the two GC peaks at the same m/z
is less than 10 percent of the height of the shorter of the two peaks.
If significant GC and spectral overlap occur, RR is computed using the
following equation:
RR = (Ry - Rm) (RX + 1)/
(Rm - RX) (Ry + 1), where RX
is measured as shown in Figure 3A, Ry is measured as shown in
Figure 3B, and Rm is measured as shown in Figure 3C. For
example, RX = 46100/4780 = 9.644, Ry = 2650/43600
= 0.0608, Rm = 49200/48300 = 1.019. amd RR = 1.114.
7.4.5 To calibrate the analytical system by isotope dilution,
analyze a 1.0 [micro]L aliquot of each of the calibration standards
(Section 6.13) using the procedure in Section 11. Compute the RR at each
concentration.
7.4.6 Linearity--if the ratio of relative response to concentration
for any compound is constant (less than 20 percent coefficient of
variation) over the 5 point calibration range, and averaged relative
response/concentration ratio may be used for that compound; otherwise,
the complete calibration curve for that compound shall be used over the
5 point calibration range.
7.5 Calibration by internal standard--used when criteria for istope
dilution (Section 7.4) cannot be met. The internal standard to be used
for both acid and base/neutral analyses is 2,2'-difluorobiphenyl. The
internal standard method is also applied to determination of compounds
having no labeled analog, and to measurement of labeled compounds for
intra-laboratory statistics (Sections 8.4 and 12.7.4).
7.5.1 Response factors--calibration requires the determination of
response factors (RF) which are defined by the following equation:
RF = (As x Cis)/(Ais x
Cs), where
As is the area of the characteristic mass for the
compmund in the daily standard
Ais is the area of the characteristic mass for the
internal standard
Cis is the concentration of the internal standard
([micro]g/mL)
Cs is the concentration of the compound in the daily
standard ([micro]g/mL)
7.5.1.1 The response factor is determined for at least five
concentrations appropriate to the response of each compound (Section
6.13); nominally, 10, 20, 50, 100, and 200 [micro]g/mL. The amount of
internal standard added to each extract is the same (100 [micro]g/mL) so
that Cis remains constant. The RF is plotted vs concentration
for each compound in the standard (Cs) to produce a
calibration curve.
7.5.1.2 Linearity--if the response factor (RF) for any compound is
constant (less than 35 percent coefficient of variation) over the 5
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point calibration range, an averaged response factor may be used for
that compound; otherwise, the complete calibration curve for that
compound shall be used over the 5 point range.
7.6 Combined calibration--by using calibration solutions (Section
6.13) containing the pollutants, labeled compounds, and the internal
standard, a single set of analyses can be used to produce calibration
curves for the isotope dilution and internal standard methods. These
curves are verified each shift (Section 12.5) by analyzing the 100
[micro]g/mL calibration standard (Section 6.13). Recalibration is
required only if calibration verification (Section 12.5) criteria cannot
be met.
8. Quality Assurance/Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality assurance program. The minimum requirements of this
program consist of an initial demonstration of laboratory capability,
analysis of samples spiked with labeled compounds to evaluate and
document data quality, and analysis of standards and blanks as tests of
continued performance. Laboratory performance is compared to established
performance criteria to determine if the results of analyses meet the
performance characteristics of the method.
8.1.1 The analyst shall make an initial demonstration of the ability
to generate acceptable accuracy and precision with this method. This
ability is established as described in Section 8.2.
8.1.2 The analyst is permitted to modify this method to improve
separations or lower the costs of measurements, provided all performance
specifications are met. Each time a modification is made to the method,
the analyst is required to repeat the procedure in Section 8.2 to
demonstrate method performance.
8.1.3 Analyses of blanks are required to demonstrate freedom from
contamination. The procedures and criteria for analysis of a blank are
described in Section 8.5.
8.1.4 The laboratory shall spike all samples with labeled compounds
to monitor method performance. This test is described in Section 8.3.
When results of these spikes indicate atypical method performance for
samples, the samples are diluted to bring method performance within
acceptable limits (Section 15).
8.1.5 The laboratory shall, on an on-going basis, demonstrate
through calibration verification and the analysis of the precision and
recovery standard (Section 6.14) that the analysis system is in control.
These procedures are described in Sections 12.1, 12.5, and 12.7.
8.1.6 The laboratory shall maintain records to define the quality of
data that is generated. Development of accuracy statements is described
in Section 8.4.
8.2 Initial precision and accuracy--to establish the ability to
generate acceptable precision and accuracy, the analyst shall perform
the following operations:
8.2.1 Extract, concentrate, and analyze two sets of four one-liter
aliquots (8 aliquots total) of the precision and recovery standard
(Section 6.14) according to the procedure in Section 10.
8.2.2 Using results of the first set of four analyses, compute the
average recovery (X) in [micro]g/mL and the standard deviation of the
recovery (s) in [thetas]g/[micro]L for each compound, by isotope
dilution for pollutants with a labeled analog, and by internal standard
for labeled compounds and pollutants with no labeled analog.
8.2.3 For each compound, compare s and X with the corresponding
limits for initial precision and accuracy in Table 8. If s and X for all
compounds meet the acceptance criteria, system performance is acceptable
and analysis of blanks and samples may begin. If, however, any
individual s exceeds the precision limit or any individual X falls
outside the range for accuracy, system performance is unacceptable for
that compound.
Note: The large number of compounds in Table 8 present a substantial
probability that one or more will fail the acceptance criteria when all
compounds are analyzed. To determine if the analytical system is out of
control, or if the failure can be attributed to probability, proceed as
follows:
8.2.4 Using the results of the second set of four analyses, compute
s and X for only those compounds which failed the test of the first set
of four analyses (Section 8.2.3). If these compounds now pass, system
performance is acceptable for all compounds and analysis of blanks and
samples may begin. If, however, any of the same compoulds fail again,
the analysis system is not performing properly for these compounds. In
this event, correct the problem and repeat the entire test (Section
8.2.1).
8.3 The laboratory shall spike all samples with labeled compounds to
assess method performance on the sample matrix.
8.3.1 Analyze each sample according to the method in Section 10.
8.3.2 Compute the percent recovery (P) of the labeled compounds
using the internal standard methmd (Section 7.5).
8.3.3 Compare the labeled compound recovery for each compound with
the corresponding limits in Table 8. If the recovery of any compounds
falls outside its warning limit, method performance is unacceptable for
that compound in that sample, Therefore, the sample is complex and is to
be diluted and reanalyzed per Section 15.4.
8.4 As part of the QA program for the laboratory, method accuracy
for wastewater samples shall be assessed and records shall
[[Page 368]]
be maintained. After the analysis of five wastewater samples for which
the labeled compounds pass the tests in Section 8.3, compute the average
percent recovery (P) and the standard deviation of the percent recovery
(sp) for the labeled compounds only. Express the accuracy
assessment as a percent recovery interval from P--2 sp to P +
2sp. For example, if P = 90% and sp = 10%, the
accuracy interval is expressed as 70-100%. Update the accuracy
assessment for each compound on a regular basis (e.g. after each 5-10
new accuracy measurements).
8.5 Blanks--reagent water blanks are analyzed to demonstrate freedom
from contamination.
8.5.1 Extract and concentrate a blank with each sample lot (samples
started through the extraction process on the same 8 hr shift, to a
maximum of 20 samples). Analyze the blank immediately after analysis of
the precision and recovery standard (Section 6.14) to demonstrate
freedom from contamination.
8.5.2 If any of the compounds of interest (Tables 1 and 2) or any
potentially interfering compound is found in a blank at greater than 10
[micro]g/L (assuming a response factor of 1 relative to the internal
standard for compounds not listed in Tables 1 and 2), analysis of
samples is halted until the source of contamination is eliminated and a
blank shows no evidence of contamination at this level.
8.6 The specifications contained in this method can be met if the
apparatus used is calibrated properly, then maintained in a calibrated
state. The standards used for calibration (Section 7), calibration
verification (Section 12.5), and for initial (Section 8.2) and on-going
(Section 12.7) precision and recovery should be identical, so that the
most precise results will be obtained. The GC/MS instrument in
particular will provide the most reproducible results if dedicated to
the settings and conditions required for the analysis of semi-volatiles
by this method.
8.7 Depending on specific program requirements, field replicates may
be collected to determine the precision of the sampling technique, and
spiked samples may be required to determine the accuracy of the analysis
when internal or external standard methods are used.
9. Sample Collection, Preservation, and Handling
9.1 Collect samples in glass containers following conventional
sampling practices (Reference 7). Composite samples are collected in
refrigerated glass containers (Section 5.1.3) in accordance with the
requirements of the sampling program.
9.2 Maintain samples at 0-4 [deg]C from the time collectimn until
extraction. If residual chlorine is present, add 80 mg sodium
thiosulfate per liter of water. EPA Methods 330.4 and 330.5 may be used
to measure residual chlorine (Reference 8).
9.3 Begin sample extraction within seven days of collection, and
analyze all extracts within 40 days of extraction.
10. Sample Extraction and Concentration (See Figure 4)
10.1 Labeled compound spiking--measure 1.00 0.01 liter of sample into a glass container. For
untreated effluents, and samples which are expected to be difficult to
extract and/or concentrate, measure an additional 10.0 0.1 mL and dilute to a final volume of 1.00 0.01 liter with reagent water in a glass container.
10.1.1 For each sample or sample lot (to a maximum of 20) to be
extracted at the same time, place three 1.00 0.10
liter aliquots of reagent water in glass containers.
10.1.2 Spike 0.5 mL of the labeled compound spiking solution
(Section 6.8) into all samples and one reagant water aliquot.
10.1.3 Spike 1.0 mL of the precision and recovery standard (Section
6.14) into the two remaining reagent water aliquots.
10.1.4 Stir and equilibrate all solutions for 1-2 hr.
10.2 Base/neutral extraction--place 100-150 mL methylene chloride in
each continuous extractor and 200-300 in each distilling flask.
10.2.1 Pour the sample(s), blank, and standard aliquots into the
extractors. Rinse the glass containers with 50-100 mL methylene chloride
and add to the respective extractor.
10.2.2 Adjust the pH of the waters in the extractors to 12-13 with
6N NaOH while monitoring with a pH meter. Begin the extraction by
heating the flask until the methylene chloride is boiling. When properly
adjusted, 1-2 drops of methylene chloride per second will fall from the
condensor tip into the water. After 1-2 hours of extraction, test the pH
and readjust to 12-13 if required. Extract for 18-24 hours.
10.2.3 Remove the distilling flask, estimate and record the volume
of extract (to the nearest 100 mL), and pour the contents through a
drying column containing 7 to 10 cm anhydrous sodium sulfate. Rinse the
distilling flask with 30-50 mL of methylene chloride and pour through
the drying column. Collect the solution in a 500 mL K-D evaporator flask
equipped with a 10 mL concentrator tube. Seal, label as the base/neutral
fraction, and concentrate per Sections 10.4 to 10.5.
10.3 Acid extraction--adjust the pH of the waters in the extractors
to 2 or less using 6N sulfuric acid. Charge clean distilling flasks with
300-400 mL of methylene chloride. Test and adjust the pH of the waters
after the first 1-2 hr of extraction. Extract for 18-24 hours.
10.3.1 Repeat Section 10.2.3, except label as the acid fraction.
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10.4 Concentration--concentrate the extracts in separate 500 mL K-D
flasks equipped with 10 mL concentrator tubes.
10.4.1 Add 1 to 2 clean boiling chips to the flask and attach a
three-ball macro Snyder column. Prewet the column by adding
approximately one mL of methylene chloride through the top. Place the K-
D apparatus in a hot water bath so that the entire lower rounded surface
of the flask is bathed with steam. Adjust the vertical position of the
apparatus and the water temperature as required to complete the
concentration in 15 to 20 minutes. At the proper rate of distillation,
the balls of the column will actively chatter but the chambers will not
flood. When the liquid has reached an apparent volume of 1 mL, remove
the K-D apparatus from the bath and allow the solvent to drain and cool
for at least 10 minutes. Remove the Snyder column and rinse the flask
and its lower joint into the concentrator tube with 1-2 mL of methylene
chloride. A 5-mL syringe is recommended for this operation.
10.4.2 For performance standards (Sections 8.2 and 12.7) and for
blanks (Section 8.5), combine the acid and base/neutral extracts for
each at this point. Do not combine the acid and base/neutral extracts
for samples.
10.5 Add a clean boiling chip and attach a two ball micro Snyder
column to the concentrator tube. Prewet the column by adding approx 0.5
mL methylene chloride through the top. Place the apparatus in the hot
water bath. Adjust the vertical position and the water temperature as
required to complete the concentration in 5-10 minutes. At the proper
rate of distillation, the balls of the column will actively chatter but
the chambers will not flood. When the liquid reaches an apparent volume
of approx 0.5 mL, remove the apparatus from the water bath and allow to
drain and cool for at least 10 minutes. Remove the micro Snyder column
and rinse its lower joint into the concentrator tube with approx 0.2 mL
of methylene chloride. Adjust the final volume to 1.0 mL.
10.6 Transfer the concentrated extract to a clean screw-cap vial.
Seal the vial with a Teflon-lined lid, and mark the level on the vial.
Label with the sample number and fraction, and store in the dark at -20
to -10 [deg]C until ready for analysis.
11. GC/MS Analysis
11.1 Establish the operating conditions given in Table 3 or 4 for
analysis of the base/neutral or acid extracts, respectively. For
analysis of combined extracts (Section 10.4.2), use the operating
conditions in Table 3.
11.2 Bring the concentrated extract (Section 10.6) or standard
(Sections 6.13 through 6.14) to room temperature and verify that any
precipitate has redissolved. Verify the level on the extract (Sections
6.6 and 10.6) and bring to the mark with solvent if required.
11.3 Add the internal standard solution (Section 6.10) to the
extract (use 1.0 uL of solution per 0.1 mL of extract) immediately prior
to injection to minimize the possibility of loss by evaporation,
adsorption, or reaction. Mix thoroughly.
11.4 Inject a volume of the standard solution or extract such that
100 ng of the internal standard will be injected, using on-column or
splitless injection. For 1 mL extracts, this volume will be 1.0 uL.
Start the GC column initial isothermal hold upon injection. Start MS
data collection after the solvent peak elutes. Stop data collection
after the benzo (ghi) perylene or pentachlorophenol peak elutes for the
base/neutral or acid fraction, respectively. Return the column to the
initial temperature for analysis of the next sample.
12. System and Laboratory Performance
12.1 At the beginning of each 8 hr shift during which analyses are
performed, GC/MS system performance and calibration are verified for all
pollutants and labeled compounds. For these tests, analysis of the 100
[micro]g/mL calibration standard (Section 6.13) shall be used to verify
all performance criteria. Adjustment and/or recalibration (per Section
7) shall be performed until all performance criteria are met. Only after
all performance criteria are met may samples, blanks, and precision and
recovery standards be analyzed.
12.2 DFTPP spectrum validity--inject 1 [micro]L of the DFTPP
solution (Section 6.11) either separately or within a few seconds of
injection of the standard (Section 12.1) analyzed at the beginning of
each shift. The criteria in Table 5 shall be met.
12.3 Retention times--the absolute retention time of 2,2'-
difluorobiphenyl shall be within the range of 1078 to 1248 seconds and
the relative retention times of all pollutants and labeled compounds
shall fall within the limits given in Tables 3 and 4.
12.4 GC resolution--the valley height between anthracene and
phenanthrene at m/z 178 (or the analogs at m/z 188) shall not exceed 10
percent of the taller of the two peaks.
12.5 Calibration verification--compute the concentration of each
pollutant (Tables 1 and 2) by isotope dilution (Section 7.4) for those
compounds which have labeled analogs. Compute the concentration of each
pollutant which has no labeled analog by the internal standard method
(Section 7.5). Compute the concentration of the labeled compounds by the
internal standard method. These concentrations are computed based on the
calibration data determined in Section 7.
12.5.1 For each pollutant and labeled compound being tested, compare
the concentration with the calibration verification limit
[[Page 370]]
in Table 8. If all compounds meet the acceptance criteria, calibration
has been verified and analysis of blanks, samples, and precision and
recovery standards may proceed. If, however, any compound fails, the
measurement system is not performing properly for that compound. In this
event, prepare a fresh calibration standard or correct the problem
causing the failure and repeat the test (Section 12.1), or recalibrate
(Section 7).
12.6 Multiple peaks--each compound injected shall give a single,
distinct GC peak.
12.7 On-going precision and accuracy.
12.7.1 Analyze the extract of one of the pair of precision and
recovery standards (Section 10.1.3) prior to analysis of samples from
the same lot.
12.7.2 Compute the concentration of each pollutant (Tables 1 and 2)
by isotope dilution (Section 7.4) for those compounds which have labeled
analogs. Compute the concentration of each pollutant which has no
labeled analog by the internal standard method (Section 7.5). Compute
the concentration of the labeled compounds by the internal standard
method.
12.7.3 For each pollutant and labeled compound, compare the
concentration with the limits for on-going accuracy in Table 8. If all
compounds meet the acceptance criteria, system performance is acceptable
and analysis of blanks and samples may proceed. If, however, any
individual concentration falls outside of the range given, system
performance is unacceptable for that compound.
Note: The large number of compounds in Table 8 present a substantial
probability that one or more will fail when all compounds are analyzed.
To determine if the extraction/concentration system is out of control or
if the failure is caused by probability, proceed as follows:
12.7.3.1 Analyze the second aliquot of the pair of precision and
recovery standard (Section 10.1.3).
12.7.3.2 Compute the concentration of only those pollutants or
labeled compounds that failed the previous test (Section 12.7.3). If
these compounds now pass, the extraction/concentration processes are in
control and analysis of blanks and samples may proceed. If, however, any
of the same compounds fail again, the extraction/concentration processes
are not being performed properly for these compounds. In this event,
correct the problem, re-extract the sample lot (Section 10) and repeat
the on-going precision and recovery test (Section 12.7).
12.7.4 Add results which pass the specifications in Section 12.7.2
to initial and previous on-going data. Update QC charts to perform a
graphic representation of continued laboratory performance (Figure 5).
Develop a statement of laboratory accuracy for each pollutant and
labeled compound by calculating the average percent recovery (R) and the
standard deviation of percent recovery (sr). Express the
accuracy as a recovery interval from R-2sr to R +
2sr. For example, if R = 95% and sr = 5%, the
accuracy is 85-105%.
13. Qualitative Determination
13.1 Qualititative determination is accomplished by comparison of
data from analysis of a sample or blank with data from analysis of the
shift standard (Section 12.1) and with data stored in the spectral
libraries (Section 7.2.4). Identification is confirmed when spectra and
retention times agree per the criteria below.
13.2 Labeled compounds and pollutants having no labeled analog:
13.2.1 The signals for all characteristic masses stored in the
spectral library (Section 7.2.4) shall be present and shall maximize
within the same two consecutive scans.
13.2.2 Either (1) the background corrected EICP areas, or (2) the
corrected relative intensities of the mass spectral peaks at the GC peak
maximum shall agree within a factor of two (0.5 to 2 times) for all
masses stored in the library.
13.2.3 The retention time relative to the nearest eluted internal
standard shall be within 15 scans or 15 seconds, whichever is greater of this difference in
the shift standard (Section 12.1).
13.3 Pollutants having a labled analog:
13.3.1 The signals for all characteristic masses stored in the
spectral library (Section 7.2.4) shall be present and shall maximize
within the same two consecutive scans.
13.3.2. Either (1) the background corrected EICP areas, or (2) the
corrected relative intensities of the mass spectral peaks at the GC peak
maximum shall agree within a factor of two for all masses stored in the
spectral library.
13.3.3. The retention time difference between the pollutant and its
labeled analog shall agree within 6 scans or
6 seconds (whichever is greater) of this
difference in the shift standard (Section 12.1).
13.4 Masses present in the experimental mass spectrum that are not
present in the reference mass spectrum shall be accounted for by
contaminant or background ions. If the experimental mass spectrum is
contaminated, an experienced spectrometrist (Section 1.4) is to
determine the presence or absence of the cmmpound.
14. Quantitative Determination
14.1 Isotope dilution--by adding a known amount of a labeled
compound to every sample prior to extraction, correction for recovery of
the pollutant can be made because the pollutant and its labeled analog
exhibit the same effects upon extraction, concentration, and gas
chromatography. Relative response (RR) values for mixtures are used in
conjunction with calibration curves described in
[[Page 371]]
Section 7.4 to determine concentrations directly, so long as labeled
compound spiking levels are constant. For the phenml example given in
Figure 1 (Section 7.4.1), RR would be equal to 1.114. For this RR value,
the phenol calibration curve given in Figure 1 indicates a concentration
of 27 [micro]g/mL in the sample extract (Cex).
14.2 Internal standard--compute the concentration in the extract
using the response factor determined from calibration data (Section 7.5)
and the following equation: Cex([micro]g/mL) = (As
x Cis/(Ais x RF) where Cex is the
concentration of the compound in the extract, and the other terms are as
defined in Section 7.5.1.
14.3 The concentration of the pollutant in water is computed using
the volumes of the original water sample (Section 10.1) and the final
extract volume (Section 10.5), as follows: Concentration in water
([micro]g/L) = (Cex x Vex)/Vs where
Vex is the extract volume in mL, and Vs is the
sample volume in liters.
14.4 If the EICP area at the quantitiation mass for any compound
exceeds the calibration range of the system, the extract of the dilute
aliquot (Section 10.1) is analyzed by isotope dilution; otherwise, the
extract is diluted by a factor of 10, 9 [micro]L of internal standard
solution (Section 6.10) are added to a 1.0 mL aliquot, and this diluted
extract is analyzed by the internal standard method (Section 14.2).
Quantify each compound at the highest concentration level within the
calibration range.
14.5 Report results for all pollutants and labeled compounds (Tables
1 and 2) found in all standards, blanks, and samples in [micro]g/L, to
three significant figures. Results for samples which have been diluted
are reported at the least dilute level at which the area at the
quantitation mass is within the calibration range (Section 14.4) and the
labeled compound recovery is within the normal range for the method
(Section 15.4).
15. Analysis of Complex Samples
15.1 Untreated effluents and other samples frequently contain high
levels (1000 [micro]g/L) of the compounds of interest,
interfering compounds, and/or polymeric materials. Some samples will not
concentrate to one mL (Section 10.5); others will overload the GC column
and/or mass spectrometer.
15.2 Analyze the dilute aliquot (Section 10.1) when the sample will
not concentrate to 1.0 mL. If a dilute aliquot was not extracted, and
the sample holding time (Section 9.3) has not been exceeded, dilute an
aliquot of the sample with reagent water and re-extract (Section 10.1);
otherwise, dilute the extract (Section 14.4) and analyze by the internal
standard method (Section 14.2).
15.3 Recovery of internal standard--the EICP area of the internal
standard should be within a factor of two of the area in the shift
standard (Section 12.1). If the absolute areas of the labeled compounds
are within a factor of two of the respective areas in the shift
standard, and the internal standard area is less than one-half of its
respective area, then internal standard loss in the extract has
occurred. In this case, use one of the labeled compounds (perferably a
polynuclear aromatic hydrocarbon) to compute the concentration of a
pollutant with no labeled analog.
15.4 Recovery of labeled compounds--in most samples, labeled
compound recoveries will be similar to those from reagent water (Section
12.7). If the labeled compound recovery is outside the limits given in
Table 8, the dilute extract (Section 10.1) is analyzed as in Section
14.4. If the recoveries of all labeled compounds and the internal
staldard are low (per the criteria above), then a loss in instrument
sensitivity is the most likely cause. In this case, the 100 [micro]g/mL
calibration standard (Section 12.1) shall be analyzed and calibration
verified (Section 12.5). If a loss in sensitivity has occurred, the
instrument shall be repaired, the performance specifications in Section
12 shall be met, and the extract reanalyzed. If a loss in instrument
sensitivity has not occurred, the method does not work on the sample
being analyzed and the result may not be reported for regulatory
compliance purposes.
16. Method Performance
16.1 Interlaboratory performance for this method is detailed in
references 9 and 10.
16.2 A chromatogram of the 100 [micro]g/mL acid/base/neutral
calibration standard (Section 6.13) is shown in Figure 6.
References
1. ``Performance Tests for the Evaluation of Computerized Gas
Chromatography/Mass Spectrometry Equipment and Laboratories'' USEPA,
EMSL/Cincinnati, OH 45268, EPA-600/4-80-025 (April 1980).
2. ``Working with Carcinogens,'' DHEW, PHS, CDC, NIOSH, Publication
77-206, (August 1977).
3. ``OSHA Safety and Health Standards, General Industry'' OSHA 2206,
29 CFR part 1910 (January 1976).
4. ``Safety in Academic Chemistry Laboratories, '' ACS Committee on
Chemical Safety (1979).
5. ``Reference Compound to Calibrate Ion Abundance Measurement in
Gas Chromatography-Mass Spectrometry Systems,'' J.W. Eichelberger, L.E.
Harris, and W.L. Budde, Anal. Chem., 47, 955 (1975).
6. ``Handbook of Analytical Quality Control in Water and Wastewater
Laboratories,'' USEPA, EMSL/Cincinnati, OH 45268, EPA-600/4-79-019
(March 1979).
7. ``Standard Practice for Sampling Water,'' ASTM Annual Book of
Standards, ASTM, Philadelphia, PA, 76 (1980).
[[Page 372]]
8. ``Methods 330.4 and 330.5 for Total Residual Chlorine,'' USEPA,
EMSL/ Cincinnati, OH 45268, EPA 600/4-70-020 (March 1979).
9. Colby, B.N., Beimer, R.G., Rushneck, D.R., and Telliard, W.A.,
``Isotope Dilution Gas Chromatography-Mass Spectrometry for the
determination of Priority Pollutants in Industrial Effluents.'' USEPA,
Effluent Guidelines Division, Washington, DC 20460 (1980).
10. ``Inter-laboratory Validation of US Environmental Protection
Agency Method 1625,'' USEPA, Effluent Guidelines Division, Washington,
DC 20460 (June 15, 1984).
Table 1--Base/Neutral Extractable Compounds
------------------------------------------------------------------------
CAS
Compound STORET registry EPA-EGD NPDES
------------------------------------------------------------------------
Acenaphthene................. 34205 83-32-9 001 B 001 B
Acenaphthylene............... 34200 208-96-8 077 B 002 B
Anthracene................... 34220 120-12-7 078 B 003 B
Benzidine.................... 39120 92-87-5 005 B 004 B
Benzo(a)anthracene........... 34526 56-55-3 072 B 005 B
Benzo(b)fluoranthene......... 34230 205-99-2 074 B 007 B
Benzo(k)fluoranthene......... 34242 207-08-9 075 B 009 B
Benzo(a)pyrene............... 34247 50-32-8 073 B 006 B
Benzo(ghi)perylene........... 34521 191-24-2 079 B 008 B
Biphenyl (Appendix C)........ 81513 92-52-4 512 B
Bis(2-chloroethyl) ether..... 34273 111-44-4 018 B 011 B
Bis(2-chloroethyoxy)methane.. 34278 111-91-1 043 B 010 B
Bis(2-chloroisopropyl) ether. 34283 108-60-1 042 B 012 B
Bis(2-ethylhexyl) phthalate.. 39100 117-81-7 066 B 013 B
4-bromophenyl phenyl ether... 34636 101-55-3 041 B 014 B
Butyl benzyl phthalate....... 34292 85-68-7 067 B 015 B
n-C10 (Appendix C)........... 77427 124-18-5 517 B
n-C12 (Appendix C)........... 77588 112-40-2 506 B
n-C14 (Appendix C)........... 77691 629-59-4 518 B
n-C16 (Appendix C)........... 77757 544-76-3 519 B
n-C18 (Appendix C)........... 77804 593-45-3 520 B
n-C20 (Appendix C)........... 77830 112-95-8 521 B
n-C22 (Appendix C)........... 77859 629-97-0 522 B
n-C24 (Appendix C)........... 77886 646-31-1 523 B
n-C26 (Appendix C)........... 77901 630-01-3 524 B
n-C28 (Appendix C)........... 78116 630-02-4 525 B
n-C30 (Appendix C)........... 78117 638-68-6 526 B
Carbazole (4c)............... 77571 86-74-8 528 B
2-chloronaphthalene.......... 34581 91-58-7 020 B 016 B
4-chlorophenyl phenyl ether.. 34641 7005-72-3 040 B 017 B
Chrysene..................... 34320 218-01-9 076 B 018 B
P-cymene (Appendix C)........ 77356 99-87-6 513 B
Dibenzo(a,h)anthracene....... 34556 53-70-3 082 B 019 B
Dibenzofuran (Appendix C and 81302 132-64-9 505 B
4c).........................
Dibenzothiophene (Synfuel)... 77639 132-65-0 504 B
Di-n-butyl phthalate......... 39110 84-74-2 068 B 026 B
1,2-dichlorobenzene.......... 34536 95-50-1 025 B 020 B
1,3-dichlorobenzene.......... 34566 541-73-1 026 B 021 B
1,4-dichlorobenzene.......... 34571 106-46-7 027 B 022 B
3,3'-dichlorobenzidine....... 34631 91-94-1 028 B 023 B
Diethyl phthalate............ 34336 84-66-2 070 B 024 B
2,4-dimethylphenol........... 34606 105-67-9 034 A 003 A
Dimethyl phthalate........... 34341 131-11-3 071 B 025 B
2,4-dinitrotoluene........... 34611 121-14-2 035 B 027 B
2,6-dinitrotoluene........... 34626 606-20-2 036 B 028 B
Di-n-octyl phthalate......... 34596 117-84-0 069 B 029 B
Diphenylamine (Appendix C)... 77579 122-39-4 507 B
Diphenyl ether (Appendix C).. 77587 101-84-8 508 B
1,2-diphenylhydrazine........ 34346 122-66-7 037 B 030 B
Fluoranthene................. 34376 206-44-0 039 B 031 B
Fluorene..................... 34381 86-73-7 080 B 032 B
Hexachlorobenzene............ 39700 118-74-1 009 B 033 B
Hexachlorobutadiene.......... 34391 87-68-3 052 B 034 B
Hexachloroethane............. 34396 67-72-1 012 B 036 B
Hexachlorocyclopentadiene.... 34386 77-47-4 053 B 035 B
Indeno(1,2,3-cd)pyrene....... 34403 193-39-5 083 B 037 B
Isophorone................... 34408 78-59-1 054 B 038 B
Naphthalene.................. 34696 91-20-3 055 B 039 B
B-naphthylamine (Appendix C). 82553 91-59-8 502 B
Nitrobenzene................. 34447 98-95-3 056 B 040 B
N-nitrosodimethylamine....... 34438 62-75-9 061 B 041 B
N-nitrosodi-n-propylamine.... 34428 621-64-7 063 B 042 B
N-nitrosodiphenylamine....... 34433 86-30-3 062 B 043 B
[[Page 373]]
Phenanthrene................. 34461 85-01-8 081 B 044 B
Phenol....................... 34694 108-95-2 065 A 010 A
a-Picoline (Synfuel)......... 77088 109-06-89 503 B
Pyrene....................... 34469 129-00-0 084 B 045 B
styrene (Appendix C)......... 77128 100-42-5 510 B
a-terpineol (Appendix C)..... 77493 98-55-5 509 B
1,2,3-trichlorobenzene (4c).. 77613 87-61-6 529 B
1,2,4-trichlorobenzene....... 34551 120-82-1 008 B 046 B
------------------------------------------------------------------------
Table 2--Acid Extractable Compounds
------------------------------------------------------------------------
CAS
Compound STORET registry EPA-EGD NPDES
------------------------------------------------------------------------
4-chloro-3-methylphenol...... 34452 59-50-7 022 A 008 A
2-chlorophenol............... 34586 95-57-8 024 A 001 A
2,4-dichlorophenol........... 34601 120-83-2 031 A 002 A
2,4-dinitrophenol............ 34616 51-28-5 059 A 005 A
2-methyl-4,6-dinitrophenol... 34657 534-52-1 060 A 004 A
2-nitrophenol................ 34591 88-75-5 057 A 006 A
4-nitrophenol................ 34646 100-02-7 058 A 007 A
Pentachlorophenol............ 39032 87-86-5 064 A 009 A
2,3,6-trichlorophenol (4c)... 77688 93-37-55 530 A
2,4,5-trichlorophenol (4c)... ........ 95-95-4 531 A
2,4,6-trichlorophenol........ 34621 88-06-2 021 A 011 A
------------------------------------------------------------------------
Table 3--Gas Chromatography of Base/Neutral Extractable Compounds
------------------------------------------------------------------------
Retention time Detection
EGD ------------------------------------ limit \2\
No. Compound Mean ([micro]g/
\1\ (sec) EGD Ref Relative L)
------------------------------------------------------------------------
164 2,2'- 1163 164 1.000-1.000 10
difluorobipheny
l (int std)....
061 N- 385 164 ns 50
nitrosodimethyl
amine..........
603 alpha picoline- 417 164 0.326-0.393 50
d7.............
703 alpha picoline.. 426 603 1.006-1.028 50
610 styrene-d5...... 546 164 0.450-0.488 10
710 styrene......... 549 610 1.002-1.009 10
613 p-cymene-d14.... 742 164 0.624-0.652 10
713 p-cymene........ 755 613 1.008-1.023 10
265 phenol-d5....... 696 164 0.584-0.613 10
365 phenol.......... 700 265 0.995-1.010 10
218 bis(2- 696 164 0.584-0.607 10
chloroethyl)
ether-d8.......
318 bis(2- 704 218 1.007-1.016 10
chloroethyl)
ether..........
617 n-decane-d22.... 698 164 0.585-0.615 10
717 n-decane........ 720 617 1.022-1.038 10
226 1,3- 722 164 0.605-0.636 10
dichlorobenzene-
d4.............
326 1,3- 724 226 0.998-1.008 10
dichlorobenzene
227 1,4- 737 164 0.601-0.666 10
dichlorobenzene-
d4.............
327 1,4- 740 227 0.997-1.009 10
dichlorobenzene
225 1,2- 758 164 0.632-0.667 10
dichlorobenzene-
d4.............
325 1,2- 760 225 0.995-1.008 10
dichlorobenzene
242 bis(2- 788 164 0.664-0.691 10
chloroisopropyl
) ether-d12....
342 bis(2- 799 242 1.010-1.016 10
chloroisopropyl
) ether........
212 hexachloroethane- 819 164 0.690-0.717 10
13C............
312 hexachloroethane 823 212 0.999-1.001 10
063 N-nitrosodi-n- 830 164 ns 20
propylamine....
256 nitrobenzene-d5. 845 164 0.706-0.727 10
356 nitrobenzene.... 849 256 1.002-1.007 10
254 isophorone-d8... 881 164 0.747-0.767 10
354 isophorone...... 889 254 0.999-1.017 10
234 2,4-dimethyl 921 164 0.781-0.803 10
phenol-d3......
334 2,4- 924 234 0.999-1.003 10
dimethylphenol.
043 bis(2- 939 164 ns 10
chloroethoxy)
methane........
208 1,2,4- 955 164 0.813-0.830 10
trichlorobenzen
e-d3...........
308 1,2,4- 958 208 1.000-1.005 10
trichlorobenzen
e..............
255 naphthalene-d8.. 963 164 0.819-0.836 10
355 naphthalene..... 967 255 1.001-1.006 10
609 alpha-terpineol- 973 164 0.829-0.844 10
d3.............
[[Page 374]]
709 alpha-terpineol. 975 609 0.998-1.008 10
606 n-dodecane-d26.. 953 164 0.730-0.908 10
706 n-dodecane...... 981 606 0.986-1.051 10
529 1,2,3- 1003 164 ns 10
trichlorobenzen
e..............
252 hexachlorobutadi 1005 164 0.856-0.871 10
ene-13C4.......
352 hexachlorobutadi 1006 252 0.999-1.002 10
ene............
253 hexachlorocyclop 1147 164 0.976-0.986 10
entadiene-13C4.
353 hexachlorocyclop 1142 253 0.999-1.001 10
entadiene......
220 2- 1185 164 1.014-1.024 10
chloronaphthale
ne-d7..........
320 2- 1200 220 0.997-1.007 10
chloronaphthale
ne.............
518 n-tetradecane... 1203 164 ns 10
612 Biphenyl-d10.... 1205 164 1.016-1.027 10
712 Biphenyl........ 1195 612 1.001-1.006 10
608 Diphenyl ether- 1211 164 1.036-1.047 10
d10............
708 Diphenyl ether.. 1216 608 0.997-1.009 10
277 Acenaphthylene- 1265 164 1.080-1.095 10
d8.............
377 Acenaphthylene.. 1247 277 1.000-1.004 10
271 Dimethyl 1269 164 1.083-1.102 10
phthalate-d4...
371 Dimethyl 1273 271 0.998-1.005 10
phthalate......
236 2,6- 1283 164 1.090-1.112 10
dinitrotoluene-
d3.............
336 2,6- 1300 236 1.001-1.005 10
dinitrotoluene.
201 Acenaphthene-d10 1298 164 1.107-1.125 10
301 Acenaphthene.... 1304 201 0.999-1.009 10
605 Dibenzofuran-d8. 1331 164 1.134-1.155 10
705 Dibenzofuran.... 1335 605 0.998-1.007 10
602 Beta- 1368 164 1.163-1.189 50
naphthylamine-
d7.............
702 Beta- 1371 602 0.996-1.007 50
naphthylamine..
280 Fluorene-d10.... 1395 164 1.185-1.214 10
380 Fluorene........ 1401 281 0.999-1.008 10
240 4-chlorophenyl 1406 164 1.194-1.223 10
phenyl ether-d5
340 4-chlorophenyl 1409 240 0.990-1.015 10
phenyl ether...
270 Diethyl 1409 164 1.197-1.229 10
phthalate-d4...
370 Diethyl 1414 270 0.996-1.006 10
phthalate......
619 n-hexadecane-d34 1447 164 1.010-1.478 10
719 n-hexadecane.... 1469 619 1.013-1.020 10
235 2,4- 1359 164 1.152-1.181 10
dinitrotoluene-
d3.............
335 2,4- 1344 235 1.000-1.002 10
dinitrotoluene.
237 1,2- 1433 164 1.216-1.248 20
diphenylhydrazi
ne-d8..........
337 1,2- 1439 237 0.999-1.009 20
diphenylhydrazi
ne (\3\).......
607 Diphenylamine- 1437 164 1.213-1.249 20
d10............
707 Diphenylamine... 1439 607 1.000-1.007 20
262 N- 1447 164 1.225-1.252 20
nitrosodiphenyl
amine-d6.......
362 N- 1464 262 1.000-1.002 20
nitrosodiphenyl
amine (\4\)....
041 4-bromophenyl 1498 164 1.271-1.307 10
phenyl ether...
209 Hexachlorobenzen 1521 164 1.288-1.327 10
e-13C6.........
309 Hexachlorobenzen 1522 209 0.999-1.001 10
e..............
281 Phenanthrene-d10 1578 164 1.334-1.380 10
520 n-octadecane.... 1580 164 ns 10
381 Phenanthrene.... 1583 281 1.000-1.005 10
278 Anthracene-d10.. 1588 164 1.342-1.388 10
378 Anthracene...... 1592 278 0.998-1.006 10
604 Dibenzothiophene- 1559 164 1.314-1.361 10
d8.............
704 Dibenzothiophene 1564 604 1.000-1.006 10
528 Carbazole....... 1650 164 ns 20
621 n-eicosane-d42.. 1655 164 1.184-1.662 10
721 n-eicosane...... 1677 621 1.010-1.021 10
268 Di-n-butyl 1719 164 1.446-1.510 10
phthalate-d4...
368 Di-n-butyl 1723 268 1.000-1.003 10
phthalate......
239 Fluoranthene-d10 1813 164 1.522-1.596 10
339 Fluoranthene.... 1817 239 1.000-1.004 10
284 Pyrene-d10...... 1844 164 1.523-1.644 10
384 Pyrene.......... 1852 284 1.001-1.003 10
205 Benzidine-d8.... 1854 164 1.549-1.632 50
305 Benzidine....... 1853 205 1.000-1.002 50
522 n-docosane...... 1889 164 ns 10
623 n-tetracosane- 1997 164 1.671-1.764 10
d50............
723 n-tetracosane... 2025 612 1.012-1.015 10
067 Butylbenzyl 2060 164 ns 10
phthalate......
276 Chrysene-d12.... 2081 164 1.743-1.837 10
376 Chrysene........ 2083 276 1.000-1.004 10
[[Page 375]]
272 Benzo(a)anthrace 2082 164 1.735-1.846 10
ne-d12.........
372 Benzo(a)anthrace 2090 272 0.999-1.007 10
ne.............
228 3,3'- 2088 164 1.744-1.848 50
dichlorobenzidi
ne-d6..........
328 3,3'- 2086 228 1.000-1.001 50
dichlorobenzidi
ne.............
266 Bis(2- 2123 164 1.771-1.880 10
ethylhexyl)
phthalate-d4...
366 Bis(2- 2124 266 1.000-1.002 10
ethylhexyl)
phthalate......
524 n-hexacosane.... 2147 164 ns 10
269 di-n-octyl 2239 164 1.867-1.982 10
phthalate-d4...
369 di-n-octyl 2240 269 1.000-1.002 10
phthalate......
525 n-octacosane.... 2272 164 ns 10
274 Benzo(b)fluorant 2281 164 1.902-2.025 10
hene-d12.......
354 Benzo(b)fluorant 2293 274 1.000-1.005 10
hene...........
275 Benzo(k)fluorant 2287 164 1.906-2.033 10
hene-d12.......
375 Benzo(k)fluorant 2293 275 1.000-1.005 10
hene...........
273 Benzo(a)pyrene- 2351 164 1.954-2.088 10
d12............
373 Benzo(a)pyrene.. 2350 273 1.000-1.004 10
626 N-triacontane- 2384 164 1.972-2.127 10
d62............
726 N-triacontane... 2429 626 1.011-1.028 10
083 Indeno(1,2,3- 2650 164 ns 20
cd)pyrene......
082 Dibenzo(a,h)anth 2660 164 ns 20
racene.........
279 Benzo(ghi)peryle 2741 164 2.187-2.524 20
ne-d12.........
379 Benzo(ghi)peryle 2750 279 1.001-1.006 20
ne.............
------------------------------------------------------------------------
\1\ Reference numbers beginning with 0, 1 or 5 indicate a pollutant
quantified by the internal standard method; reference numbers
beginning with 2 or 6 indicate a labeled compound quantified by the
internal standard method; reference numbers beginning with 3 or 7
indicate a pollutant quantified by isotope dilution.
\2\ This is a minimum level at which the entire GC/MS system must give
recognizable mass spectra (background corrected) and acceptable
calibration points.
\3\ Detected as azobenzene.
\4\ Detected as diphenylamine.
ns = specification not available at time of release of method.
Column: 30 2 m x 0.25 0.02
mm i.d. 94% methyl, 4% phenyl, 1% vinyl bonded phase fused silica
capillary.
Temperature program: 5 min at 30 [deg]C; 30 - 280 [deg]C at 8 [deg]C per
min; isothermal at 280 [deg]C until benzo(ghi)perylene elutes.
Gas velocity: 30 5 cm/sec.
Table 4--Gas Chromatography of Acid Extractable Compounds
------------------------------------------------------------------------
Retention time Detection
EGD ------------------------------------ limit \2\
No. Compound Mean ([micro]g/
\1\ (sec) EGD Ref Relative L)
------------------------------------------------------------------------
164 2,2'- 1163 164 1.000-1.000 10
difluorobipheny
l (int std)....
224 2-chlorophenol- 701 164 0.587-0.618 10
d4.............
324 2-chlorophenol.. 705 224 0.997-1.010 10
257 2-nitrophenol-d4 898 164 0.761-0.783 20
357 2-nitrophenol... 900 257 0.994-1.009 20
231 2,4- 944 164 0.802-0.822 10
dichlorophenol-
d3.............
331 2,4- 947 231 0.997-1.006 10
dichlorophenol.
222 4-chloro-3- 1086 164 0.930-0.943 10
methylphenol-d2
322 4-chloro-3- 1091 222 0.998-1.003 10
methylphenol...
221 2,4,6- 1162 164 0.994-1.005 10
trichlorophenol-
d2.............
321 2,4,6- 1165 221 0.998-1.004 10
trichlorophenol
531 2,4,5- 1170 164 ns 10
trichlorophenol
530 2,3,6- 1195 164 ns 10
trichlorophenol
259 2,4- 1323 164 1.127-1.149 50
dinitrophenol-
d3.............
359 2,4- 1325 259 1.000-1.005 50
dinitrophenol..
258 4-nitrophenol-d4 1349 164 1.147-1.175 50
358 4-nitrophenol... 1354 258 0.997-1.006 50
260 2-methyl-4,6- 1433 164 1.216-1.249 20
dinitrophenol-
d2.............
360 2-methyl-4,6- 1435 260 1.000-1.002 20
dinitrophenol..
264 Pentachloropheno 1559 164 1.320-1.363 50
l-13C6.........
364 Pentachloropheno 1561 264 0.998-1.002 50
l..............
------------------------------------------------------------------------
\1\ Reference numbers beginning with 0, 1 or 5 indicate a pollutant
quantified by the internal standard method; reference numbers
beginning with 2 or 6 indicate a labeled compound quantified by the
internal standard method; reference numbers beginning with 3 or 7
indicate a pollutant quantified by isotope dilution.
\2\ This is a minimum level at which the entire GC/MS system must give
recognizable mass spectra (background corrected) and acceptable
calibration points.
ns = specification not available at time of release of method.
Column: 30 2m x 0.25 0.02mm
i.d. 94% methyl, 4% phenyl, 1% vinyl bonded phase fused silica
capillary.
Temperature program: 5 min at 30 [deg]C; 8 [deg]C/min. to 250 [deg]C or
until pentachlorophenol elutes.
Gas velocity: 30 5 cm/sec.
[[Page 376]]
Table 5--DFTPP Mass Intensity Specifications
------------------------------------------------------------------------
Mass Intensity required
------------------------------------------------------------------------
51 30-60 percent of mass 198.
68 Less than 2 percent of mass 69.
70 Less than 2 percent of mass 69.
127 40-60 percent of mass 198.
197 Less than 1 percent of mass 198.
199 5-9 percent of mass 198.
275 10-30 percent of mass 198.
365 greater than 1 percent of mass 198
441 present and less than mass 443
442 40-100 percent of mass 198.
443 17-23 percent of mass 442.
------------------------------------------------------------------------
Table 6--Base/Neutral Extractable Compound Characteristic Masses
------------------------------------------------------------------------
Labeled Primary m/
Compound analog z
------------------------------------------------------------------------
Acenaphthene..................................... d10 154/164
Acenaphthylene................................... d8 152/160
Anthracene....................................... d10 178/188
Benzidine........................................ d8 184/192
Benzo(a)anthracene............................... d12 228/240
Benzo(b)fluoranthene............................. d12 252/264
Benzo(k)fluoranthene............................. d12 252/264
Benzo(a)pyrene................................... d12 252/264
Benzo(ghi)perylene............................... d12 276/288
Biphenyl......................................... d10 154/164
Bis(2-chloroethyl) ether......................... d8 93/101
Bis(2-chloroethoxy)methane....................... ......... 93
Bis(2-chloroisopropyl) ether..................... d12 121/131
Bis(2-ethylhexyl) phthalate...................... d4 149/153
4-bromophenyl phenyl ether....................... ......... 248
Butyl benzyl phthalate........................... ......... 149
n-C10............................................ d22 55/66
n-C12............................................ d26 55/66
n-C14............................................ ......... 55
n-C16............................................ d34 55/66
n-C18............................................ ......... 55
n-C20............................................ d42 55/66
n-C22............................................ ......... 55
n-C24............................................ d50 55/66
n-C26............................................ ......... 55
n-C28............................................ ......... 55
n-C30............................................ d62 55/66
Carbazole........................................ d8 167/175
2-chloronaphthalene.............................. d7 162/169
4-chlorophenyl phenyl ether...................... d5 204/209
Chrysene......................................... d12 228/240
p-cymene......................................... d14 114/130
Dibenzo(a,h)anthracene........................... ......... 278
Dibenzofuran..................................... d8 168/176
Dibenzothiophene................................. d8 184/192
Di-n-butyl phthalate............................. d4 149/153
1,2-dichlorobenzene.............................. d4 146/152
1,3-dichlorobenzene.............................. d4 146/152
1,4-dichlorobenzene.............................. d4 146/152
3,3'-dichlorobenzidine........................... d6 252/258
Diethyl phthalate................................ d4 149/153
2,4-dimethylphenol............................... d3 122/125
Dimethyl phthalate............................... d4 163/167
2,4-dinitrotoluene............................... d3 164/168
2,6-dinitrotoluene............................... d3 165/167
Di-n-octyl phthalate............................. d4 149/153
Diphenylamine.................................... d10 169/179
Diphenyl ether................................... d10 170/180
1,2-diphenylhydrazine \1\........................ d10 77/82
Fluoranthene..................................... d10 202/212
Fluorene......................................... d10 166/176
Hexachlorobenzene................................ 13C6 284/292
Hexachlorobutadiene.............................. 13C4 225/231
Hexachloroethane................................. 13C 201/204
Hexachlorocyclopentadiene........................ 13C4 237/241
Ideno(1,2,3-cd)pyrene............................ ......... 276
Isophorone....................................... d8 82/88
Naphthalene...................................... d8 128/136
B-naphthylamine.................................. d7 143/150
Nitrobenzene..................................... d5 123/128
N-nitrosodimethylamine........................... ......... 74
N-nitrosodi-n-propylamine........................ ......... 70
N-nitrosodiphenylamile \2\....................... d6 169/175
Phenanthrene..................................... d10 178/188
Phenol........................................... d5 94/71
a-picoline....................................... d7 93/100
Pyrene........................................... d10 202/212
Styrene.......................................... d5 104/109
a-terpineol...................................... d3 59/62
1,2,3-trichlorobenzene........................... d3 180/183
1,2,4-trichlorobenzene........................... d3 180/183
------------------------------------------------------------------------
\1\ Detected as azobenzene.
\2\ Detected as diphenylamine.
Table 7--Acid Extractable Compound Characteristic Masses
------------------------------------------------------------------------
Labeled Primary m/
Compound analog z
------------------------------------------------------------------------
4-chloro-3-methylphenol.......................... d2 107/109
2-chlorophenol................................... d4 128/132
2,4-dichlorophenol............................... d3 162/167
2,4-dinitrophenol................................ d3 184/187
2-methyl-4,6-dinitrophenol....................... d2 198/200
2-nitrophenol.................................... d4 139/143
4-nitrophenol.................................... d4 139/143
Pentachlorophenol................................ 13C6 266/272
2,3,6-trichlorophenol............................ d2 196/200
2,4,5-trichlorophenol............................ d2 196/200
2,4,6-trichlorophenol............................ d2 196/200
------------------------------------------------------------------------
Table 8--Acceptance Criteria for Performance Tests
----------------------------------------------------------------------------------------------------------------
Acceptance criteria
-----------------------------------------------------------------
EGD Initial precision and Labeled Calibration On-going
No. Compound accuracy section compound verification accuracy
\1\ 8.2.3 ([micro]g/L) recovery sec. sec. 12.5 sec. 11.6 R
----------------------- 8.3 and 14.2 P ([micro]g/ ([micro]g/
s X (percent) mL) L)
----------------------------------------------------------------------------------------------------------------
301 Acenaphthene.......................... 21 79-134 .............. 80-125 72-144
201 Acenaphthene-d10...................... 38 38-147 20-270 71-141 30-180
377 Acenaphtylene......................... 38 69-186 .............. 60-166 61-207
277 Acenaphthylene-d8..................... 31 38-146 23-239 66-152 33-168
[[Page 377]]
378 Anthracene............................ 41 58-174 .............. 60-168 50-199
278 Anthracene-d10........................ 49 31-194 14-419 58-171 23-242
305 Benzidine............................. 119 16-518 .............. 34-296 11-672
205 Benzidine-d8.......................... 269 ns-ns ns-ns ns-ns ns-ns
372 Benzo(a)anthracene.................... 20 65-168 .............. 70-142 62-176
272 Benzo(a)anthracene-d12................ 41 25-298 12-605 28-357 22-329
374 Benzo(b)fluoranthene.................. 183 32-545 .............. 61-164 20-ns
274 Benzo(b)fluoranthene-d12.............. 168 11-577 ns-ns 14-ns ns-ns
375 Benzo(k)fluoranthene.................. 26 59-143 .............. 13-ns 53-155
275 Benzo(k)fluoranthene-d12.............. 114 15-514 ns-ns 13-ns ns-685
373 Benzo(a)pyrene........................ 26 62-195 .............. 78-129 59-206
273 Benzo(a)pyrene-d12.................... 24 35-181 21-290 12-ns 32-194
379 Benzo(ghi)perylene.................... 21 72-160 .............. 69-145 58-168
279 Benzo(ghi)perylene-d12................ 45 29-268 14-529 13-ns 25-303
712 Biphenyl (Appendix C)................. 41 75-148 .............. 58-171 62-176
612 Biphenyl-d12.......................... 43 28-165 ns-ns 52-192 17-267
318 Bis(2-chloroethyl) ether.............. 34 55-196 .............. 61-164 50-213
218 Bis(2-chloroethyl) ether-d8........... 33 29-196 15-372 52-194 25-222
043 Bis(2-chloroethoxy)methane*........... 27 43-153 .............. 44-228 39-166
342 Bis(2-chloroisopropyl) ether.......... 17 81-138 .............. 67-148 77-145
242 Bis(2-chloroisopropyl)ether-d12....... 27 35-149 20-260 44-229 30-169
366 Bis(2-ethylhexyl) phthalate........... 31 69-220 .............. 76-131 64-232
266 Bis(2-ethylhexyl) phthalate-d4........ 29 32-205 18-364 43-232 28-224
041 4-bromophenyl phenyl ether*........... 44 44-140 .............. 52-193 35-172
067 Butyl benzyl phthalate*............... 31 19-233 .............. 22-450 35-170
717 n-C10 (Appendix C).................... 51 24-195 .............. 42-235 19-237
617 n-C10-d22............................. 70 ns-298 ns-ns 44-227 ns-504
706 n-C12 (Appendix C).................... 74 35-369 .............. 60-166 29-424
606 n-C12-d26............................. 53 ns-331 ns-ns 41-242 ns-408
518 n-C14 (Appendix C)*................... 109 ns-985 .............. 37-268 ns-ns
719 n-C16 (Appendix C).................... 33 80-162 .............. 72-138 71-181
619 n-C16-d34............................. 46 37-162 18-308 54-186 28-202
520 n-C18 (Appendix C)*................... 39 42-131 .............. 40-249 35-167
721 n-C20 (Appendix C).................... 59 53-263 .............. 54-184 46-301
621 n-C20-d42............................. 34 34-172 19-306 62-162 29-198
522 n-C22 (Appendix C)*................... 31 45-152 .............. 40-249 39-195
723 n-C24 (Appendix C).................... 11 80-139 .............. 65-154 78-142
623 n-C24-d50............................. 28 27-211 15-376 50-199 25-229
524 n-C26 (Appendix C)*................... 35 35-193 .............. 26-392 31-212
525 n-C28 (Appendix C)*................... 35 35-193 .............. 26-392 31-212
726 n-C30 (Appendix C).................... 32 61-200 .............. 66-152 56-215
626 n-C30-d62............................. 41 27-242 13-479 24-423 23-274
528 Carbazole (4c)*....................... 38 36-165 .............. 44-227 31-188
320 2-chloronaphthalene................... 100 46-357 .............. 58-171 35-442
220 2-chloronaphthalene-d7................ 41 30-168 15-324 72-139 24-204
322 4-chloro-3-methylphenol............... 37 76-131 .............. 85-115 62-159
222 4-chloro-3-methylphenol-d2............ 111 30-174 ns-613 68-147 14-314
324 2-chlorophenol........................ 13 79-135 .............. 78-129 76-138
224 2-chlorophenol-d4..................... 24 36-162 23-255 55-180 33-176
340 4-chlorophenyl phenyl ether........... 42 75-166 .............. 71-142 63-194
240 4-chlorophenyl phenyl ether-d5........ 52 40-161 19-325 57-175 29-212
376 Chrysene.............................. 51 59-186 .............. 70-142 48-221
276 Chrysene-d12.......................... 69 33-219 13-512 24-411 23-290
713 p-cymene (Appendix C)................. 18 76-140 .............. 79-127 72-147
613 p-cymene-d14.......................... 67 ns-359 ns-ns 66-152 ns-468
082 Dibenzo(a,h)anthracene*............... 55 23-299 .............. 13-761 19-340
705 Dibenzofuran (Appendix C)............. 20 85-136 .............. 73-136 79-146
605 Dibenzofuran-d8....................... 31 47-136 28-220 66-150 39-160
704 Dibenzothiophene (Synfuel)............ 31 79-150 .............. 72-140 70-168
604 Dibenzothiophene-d8................... 31 48-130 29-215 69-145 40-156
368 Di-n-butyl phthalate.................. 15 76-165 .............. 71-142 74-169
268 Di-n-butyl phthalate-d4............... 23 23-195 13-346 52-192 22-209
325 1,2-dichlorobenzene................... 17 73-146 .............. 74-135 70-152
225 1,2-dichlorobenzene-d4................ 35 14-212 ns-494 61-164 11-247
326 1,3-dichlorobenzene................... 43 63-201 .............. 65-154 55-225
226 1,3-dichlorobenzene-d4................ 48 13-203 ns-550 52-192 ns-260
327 1,4-dichlorobenzene................... 42 61-194 .............. 62-161 53-219
[[Page 378]]
227 1,4-dichlorobenzene-d4................ 48 15-193 ns-474 65-153 11-245
328 3,3'-dichlorobenzidine................ 26 68-174 .............. 77-130 64-185
228 3,3'-dichlorobenzidine-d6............. 80 ns-562 ns-ns 18-558 ns-ns
331 2,4-dichlorophenol.................... 12 85-131 .............. 67-149 83-135
231 2,4-dichlorophenol-d3................. 28 38-164 24-260 64-157 34-182
370 Diethyl phthalate..................... 44 75-196 .............. 74-135 65-222
270 Diethyl phthalate-d4.................. 78 ns-260 ns-ns 47-211 ns-ns
334 2,4-dimethylphenol.................... 13 62-153 .............. 67-150 60-156
234 2,4-dimethylphenol-d3................. 22 15-228 ns-449 58-172 14-242
371 Dimethyl phthalate.................... 36 74-188 .............. 73-137 67-207
271 Dimethyl phthalate-d4................. 108 ns-640 ns-ns 50-201 ns-ns
359 2,4-dinitrophenol..................... 18 72-134 .............. 75-133 68-141
259 2,4-dinitrophenol-d3.................. 66 22-308 ns-ns 39-256 17-378
335 2,4-dinitrotoluene.................... 18 75-158 .............. 79-127 72-164
235 2,4-dinitrotoluene-d3................. 37 22-245 10-514 53-187 19-275
336 2,6-dinitrotoluene.................... 30 80-141 .............. 55-183 70-159
236 2,6-dinitrotoluene-d3................. 59 44-184 17-442 36-278 31-250
369 Di-n-octyl phthalate.................. 16 77-161 .............. 71-140 74-166
269 Di-n-octyl phthalate-d4............... 46 12-383 ns-ns 21-467 10-433
707 Diphenylamine (Appendix C)............ 45 58-205 .............. 57-176 51-231
607 Diphenylamine-d10..................... 42 27-206 11-488 59-169 21-249
708 Diphenyl ether (Appendix C)........... 19 82-136 .............. 83-120 77-144
608 Diphenyl ether-d10.................... 37 36-155 19-281 77-129 29-186
337 1,2-diphenylhydrazine................. 73 49-308 .............. 75-134 40-360
237 1,2-diphenylhydrazine-d10............. 35 31-173 17-316 58-174 26-200
339 Fluoranthene.......................... 33 71-177 .............. 67-149 64-194
239 Fluoranthene-d10...................... 35 36-161 20-278 47-215 30-187
380 Fluorene.............................. 29 81-132 .............. 74-135 70-151
280 Fluorene-d10.......................... 43 51-131 27-238 61-164 38-172
309 Hexachlorobenzene..................... 16 90-124 .............. 78-128 85-132
209 Hexachlorobenzene-13C6................ 81 36-228 13-595 38-265 23-321
352 hexachlorobutadiene................... 56 51-251 .............. 74-135 43-287
252 hexachlorobutadiene-13C4.............. 63 ns-316 ns-ns 68-148 ns-413
312 hexachloroethane...................... 227 21-ns .............. 71-141 13-ns
212 hexachloroethane-13C1................. 77 ns-400 ns-ns 47-212 ns-563
353 hexachlorocyclopentadiene............. 15 69-144 .............. 77-129 67-148
253 hexachlorocyclopentadiene-13C4........ 60 ns-ns ns-ns 47-211 ns-ns
083 ideno(1,2,3-cd)pyrene*................ 55 23-299 .............. 13-761 19-340
354 isophorone............................ 25 76-156 .............. 70-142 70-168
254 isophorone-d8......................... 23 49-133 33-193 52-194 44-147
360 2-methyl-4,6-dinitrophenol............ 19 77-133 .............. 69-145 72-142
260 2-methyl-4,6-dinitrophenol-d2......... 64 36-247 16-527 56-177 28-307
355 naphthalene........................... 20 80-139 .............. 73-137 75-149
255 naphthalene-d8........................ 39 28-157 14-305 71-141 22-192
702 B-naphthylamine (Appendix C).......... 49 10-ns .............. 39-256 ns-ns
602 B-naphthylamine-d7.................... 33 ns-ns ns-ns 44-230 ns-ns
356 nitrobenzene.......................... 25 69-161 .............. 85-115 65-169
256 nitrobenzene-d5....................... 28 18-265 ns-ns 46-219 15-314
357 2-nitrophenol......................... 15 78-140 .............. 77-129 75-145
257 2-nitrophenol-d4...................... 23 41-145 27-217 61-163 37-158
358 4-nitrophenol......................... 42 62-146 .............. 55-183 51-175
258 4-nitrophenol-d4...................... 188 14-398 ns-ns 35-287 ns-ns
061 N-nitrosodimethylamile*............... 198 21-472 .............. 40-249 12-807
063 N-nitrosodi-n-proplyamine*............ 198 21-472 .............. 40-249 12-807
362 N-nitrosodiphenylamine................ 45 65-142 .............. 68-148 53-173
262 N-nitrosodiphenylamine-d6............. 37 54-126 26-256 59-170 40-166
364 pentachlorophenol..................... 21 76-140 .............. 77-130 71-150
264 pentachlorophenol-13C6................ 49 37-212 18-412 42-237 29-254
381 phenanthrene.......................... 13 93-119 .............. 75-133 87-126
281 phenanthrene-d10...................... 40 45-130 24-241 67-149 34-168
365 phenol................................ 36 77-127 .............. 65-155 62-154
265 phenol-d5............................. 161 21-210 ns-ns 48-208 ns-ns
703 a-picoline (Synfuel).................. 38 59-149 .............. 60-165 50-174
603 a-picoline-d7......................... 138 11-380 ns-ns 31-324 ns-608
384 pyrene................................ 19 76-152 .............. 76-132 72-159
284 pyrene-d10............................ 29 32-176 18-303 48-210 28-196
710 styrene (Appendix C).................. 42 53-221 .............. 65-153 48-244
[[Page 379]]
610 styrene-d5............................ 49 ns-281 ns-ns 44-228 ns-348
709 a-terpineol (Appendix C).............. 44 42-234 .............. 54-186 38-258
609 a-terpineol-d3........................ 48 22-292 ns-672 20-502 18-339
529 1,2,3-trichlorobenzene (4c)*.......... 69 15-229 .............. 60-167 11-297
308 1,2,4-trichlorobenzene................ 19 82-136 .............. 78-128 77-144
208 1,2,4-trichlorobenzene-d3............. 57 15-212 ns-592 61-163 10-282
530 2,3,6-trichlorophenol (4c)*........... 30 58-137 .............. 56-180 51-153
531 2,4,5-trichlorophenol (4c)*........... 30 58-137 .............. 56-180 51-153
321 2,4,6-trichlorophenol................. 57 59-205 .............. 81-123 48-244
221 2,4,6-trichlorophenol-d2.............. 47 43-183 21-363 69-144 34-226
----------------------------------------------------------------------------------------------------------------
\1\ Reference numbers beginning with 0, 1 or 5 indicate a pollutant quantified by the internal standard method;
reference numbers beginning with 2 or 6 indicate a labeled compound quantified by the internal standard
method; reference numbers beginning with 3 or 7 indicate a pollutant quantified by isotope dilution.
* Measured by internal standard; specification derived from related compound.
ns = no specification; limit is outside the range that can be measured reliably.
[[Page 380]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.057
[[Page 381]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.058
[[Page 382]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.059
[[Page 383]]
Attachment 1 to Method 1625
Introduction
To support measurement of several semivolatile pollutants, EPA has
developed this attachment to EPA Method 1625B. \1\ The modifications
listed in this attachment are approved only for monitoring wastestreams
from the Centralized Waste Treatment Point Source Category (40 CFR part
437) and the Landfills Point Source Category (40 CFR part 445). EPA
Method 1625B (the Method) employs sample extraction with methylene
chloride followed by analysis of the extract using capillary column gas
chromatography-mass spectrometry (GC/MS). This attachment addresses the
addition of the semivolatile pollutants listed in Tables 1 and 2 to all
applicable standard, stock, and spiking solutions utilized for the
determination of semivolatile organic compounds by EPA Method 1625B.
---------------------------------------------------------------------------
\1\ EPA Method 1625 Revision B, Semivolatile Organic Compounds by
Isotope Dilution GC/MS, 40 CFR part 136, appendix A.
---------------------------------------------------------------------------
1.0 EPA METHOD 1625 REVISION B MODIFICATION SUMMARY
The additional semivolatile organic compounds listed in Tables 1 and
2 are added to all applicable calibration, spiking, and other solutions
utilized in the determination of semivolatile compounds by EPA Method
1625. The instrument is to be calibrated with these compounds, and all
procedures and quality control tests described in the Method must be
performed.
2.0 SECTION MODIFICATIONS
Note: All section and figure numbers in this Attachment reference
section and figure numbers in EPA Method 1625 Revision B unless noted
otherwise. Sections not listed here remain unchanged.
Section 6.7 The stock standard solutions described in this section are
modified such that the analytes in Tables 1 and 2 of this
attachment are required in addition to those specified in the
Method.
Section 6.8 The labeled compound spiking solution in this section is
modified to include the labeled compounds listed in Tables 5
and 6 of this attachment.
Section 6.9 The secondary standard is modified to include the additional
analytes listed in Tables 1 and 2 of this attachment.
Section 6.12 The solutions for obtaining authentic mass spectra are to
include all additional analytes listed in Tables 1 and 2 of
this attachment.
Section 6.13 The calibration solutions are modified to include the
analytes listed in Tables 1 and 2 and the labeled compounds
listed in Tables 5 and 6 of this attachment.
Section 6.14 The precision and recovery standard is modified to include
the analytes listed in Tables 1 and 2 and the labeled
compounds listed in Tables 5 and 6 of this attachment.
Section 6.15 The solutions containing the additional analytes listed in
Tables 1 and 2 of this attachment are to be analyzed for
stability.
Section 7.2.1 This section is modified to include the analytes listed in
Tables 1 and 2 and the labeled compounds listed in Tables 5
and 6 of this attachment.
Section 7.4.5 This section is modified to include the analytes listed in
Tables 1 and 2 and the labeled compounds listed in Tables 5
and 6 in the calibration.
Section 8.2 The initial precision and recovery (IPR) requirements are
modified to include the analytes listed in Tables 1 and 2 and
the labeled compounds listed in Tables 5 and 6 of this
attachment. Additional IPR performance criteria are supplied
in Table 7 of this attachment.
Section 8.3 The labeled compounds listed in Tables 3 and 4 of this
attachment are to be included in the method performance tests.
Additional method performance criteria are supplied in Table 7
of this attachment.
Section 8.5.2 The acceptance criteria for blanks includes the analytes
listed in Tables 1 and 2 of this attachment.
Section 10.1.2 The labeled compound solution must include the labeled
compounds listed in Tables 5 and 6 of this attachment.
Section 10.1.3 The precision and recovery standard must include the
analytes listed in Tables 1 and 2 and the labeled compounds
listed in Tables 5 and 6 of this attachment.
Section 12.5 Additional QC requirements for calibration verification are
supplied in Table 7 of this attachment.
Section 12.7 Additional QC requirements for ongoing precision and
recovery are supplied in Table 7 of this attachment.
[[Page 384]]
Table 1--Base/Neutral Extractable Compounds
------------------------------------------------------------------------
Pollutant
-----------------------
Compound CAS
Registry EPA-EGD
------------------------------------------------------------------------
acetophenone \1\................................ 98-86-2 758
aniline \2\..................................... 62-53-3 757
-2,3-dichloroaniline \1\........................ 608-27-5 578
-o-cresol \1\................................... 95-48-7 771
pyridine \2\.................................... 110-86-1 1330
------------------------------------------------------------------------
CAS = Chemical Abstracts Registry.
EGD = Effluent Guidelines Division.
\1\ Analysis of this pollutant is approved only for the Centralized
Waste Treatment industry.
\2\ Analysis of this pollutant is approved only for the Centralized
Waste Treatment and Landfills industries.
Table 2--Acid Extractable Compounds
------------------------------------------------------------------------
Pollutant
-------------------------
Compound CAS
Registry EPA-EGD
------------------------------------------------------------------------
p-cresol \1\.................................. 106-44-5 1744
------------------------------------------------------------------------
CAS = Chemical Abstracts Registry.
EGD = Effluent Guidelines Division.
\1\ Analysis of this pollutant is approved only for the Centralized
Waste Treatment and Landfills industries.
Table 3--Gas Chromatography \1\ of Base/Neutral Extractable Compounds
--------------------------------------------------------------------------------------------------------------------------------------------------------
Retention time \2\ Retention time \2\
------------------------------------------------ Minimum level EGD ----------------------
EGD No. Compound \3\ ([micro]g/ No. Compound Mean EGD
Mean (sec) EGD Ref Relative L) (sec) Ref Relative
------------------------------------------------------------------------------------------------------------------- -------------------------------------------------
758...................... acetophenone \4\........ 818 658 1.003-1.005 10
757...................... aniline \5\............. 694 657 0.994-1.023 10
578...................... 2,3-dichloroaniline \4\. 1160 164 1.003-1.007 10
771...................... o-cresol \4\............ 814 671 1.005-1.009 10
1330..................... pyridine \5\............ 378 1230 1.005-1.011 10
--------------------------------------------------------------------------------------------------------------------------------------------------------
EGD = Effluent Guidelines Division.
\1\ The data presented in this table were obtained under the chromatographic conditions given in the footnote to Table 3 of EPA Method 1625B.
\2\ Retention times are approximate and are intended to be consistent with the retention times for the analytes in EPA Method 1625B.
\3\ See the definition in footnote 2 to Table 3 of EPA Method 1625B.
\4\ Analysis of this pollutant is approved only for the Centralized Waste Treatment industry.
\5\ Analysis of this pollutant is approved only for the Centralized Waste Treatment and Landfills industries.
Table 4--Gas Chromatography \1\ of Acid Extractable Compounds
----------------------------------------------------------------------------------------------------------------
Retention time \2\ Minimum level
EGD No. Compound ------------------------------------------------ ([micro]/L)
Mean (sec) EGD Ref Relative \3\
----------------------------------------------------------------------------------------------------------------
1744.................... p-cresol \4\.......... 834 1644 1.004-1.008 20
----------------------------------------------------------------------------------------------------------------
EGD = Effluent Guidelines Division.
\1\ The data presented in this table were obtained under the chromatographic conditions given in the footnote to
Table 4 of EPA Method 1625B.
\2\ Retention times are approximate and are intended to be consistent with the retention times for the analytes
in EPA Method 1625B.
\3\ See the definition in footnote 2 to Table 4 of EPA Method 1625B.
\4\ Analysis of this pollutant is approved only for the Centralized Waste Treatment and Landfills industries.
Table 5--Base/Neutral Extractable Compound Characteristic m/z's
------------------------------------------------------------------------
Primary m/z
Compound Labeled Analog \1\
------------------------------------------------------------------------
acetophenone \2\.......................... d5 105/110
aniline \3\............................... d7 93/100
o-cresol \2\.............................. d7 108/116
2,3-dichloroaniline \2\................... n/a 161
pyridine \3\.............................. d5 79/84
------------------------------------------------------------------------
m/z = mass to charge ratio.
[[Page 385]]
\1\ Native/labeled.
\2\ Analysis of this pollutant is approved only for the Centralized
Waste Treatment industry.
\3\ Analysis of this pollutant is approved only for the Centralized
Waste Treatment and Landfills industries.
Table 6--Acid Extractable Compound Characteristic m/z's
------------------------------------------------------------------------
Primary m/z
Compound Labeled Analog \1\
------------------------------------------------------------------------
p-cresol \2\.............................. d7 108/116
------------------------------------------------------------------------
m/z = mass to charge ratio.
\1\ Native/labeled.
\2\ Analysis of this pollutant is approved only for the Centralized
Waste Treatment and Landfills industries.
Table 7--Acceptance Criteria for Performance Tests
----------------------------------------------------------------------------------------------------------------
Acceptance criteria
---------------------------------------
Initial precision and Labeled Calibration On-going
accuracy section 8.2 compound verification accuracy
EGD No. Compound ([micro]g/L) recovery sec. 12.5 sec. 12.7 R
-------------------------- sec. 8.3 ([micro]g/ ([micro]g/
s ([micro]g/ and 14.2 P mL) L)
L) X (percent)
----------------------------------------------------------------------------------------------------------------
758.................... acetophenone \1\..... 34 44-167 ........... 85-115 45-162
658.................... acetophenone-d 5 \1\. 51 23-254 45-162 85-115 22-264
757.................... aniline \2\.......... 32 30-171 ........... 85-115 33-154
657.................... aniline-d 7 \2\...... 71 15-278 33-154 85-115 12-344
771.................... o-cresol \1\......... 40 31-226 ........... 85-115 35-196
671.................... o-cresol-d 7 \1\..... 23 30-146 35-196 85-115 31-142
1744................... p-cresol \2\......... 59 54-140 ........... 85-115 37-203
1644................... p-cresol-d7 \2\...... 22 11-618 37-203 85-115 16-415
578.................... 2,3-dichloroaniline 13 40-160 ........... 85-115 44-144
\1\.
1330................... pyridine \2\......... 28 10-421 ........... 83-117 18-238
1230................... pyridine-d 5 \2\..... ns 7-392 19-238 85-115 4-621
----------------------------------------------------------------------------------------------------------------
s = Standard deviation of four recovery measurements.
X = Average recovery for four recovery measurements.
EGD = Effluent Guidelines Division.
ns = no specification; limit is outside the range that can be measured reliably.
\1\ Analysis of this pollutant is approved only for the Centralized Waste Treatment industry.
\2\ Analysis of this pollutant is approved only for the Centralized Waste Treatment and Landfills industries.
[49 FR 43261, Oct. 26, 1984; 50 FR 692, 695, Jan. 4, 1985, as amended at
51 FR 23702, June 30, 1986; 62 FR 48405, Sept. 15, 1997; 65 FR 3044,
Jan. 19, 2000; 65 FR 81295, 81298, Dec. 22, 2000; 82 FR 40875, Aug. 28,
2017]
Sec. Appendix B to Part 136--Definition and Procedure for the
Determination of the Method Detection Limit--Revision 2
Definition
The method detection limit (MDL) is defined as the minimum measured
concentration of a substance that can be reported with 99% confidence
that the measured concentration is distinguishable from method blank
results.
I. Scope and Application
(1) The MDL procedure is designed to be a straightforward technique
for estimation of the detection limit for a broad variety of physical
and chemical methods. The procedure requires a complete, specific, and
well-defined analytical method. It is essential that all sample
processing steps used by the laboratory be included in the determination
of the method detection limit.
(2) The MDL procedure is not applicable to methods that do not
produce results with a continuous distribution, such as, but not limited
to, methods for whole effluent toxicity, presence/absence methods, and
microbiological methods that involve counting colonies. The MDL
procedure also is not applicable to measurements such as, but not
limited to, biochemical oxygen demand, color, pH, specific conductance,
many titration methods, and any method where low-level spiked samples
cannot be prepared. Except as described in the addendum, for the
purposes of this procedure, ``spiked samples'' are prepared from a clean
reference matrix, such as reagent water, spiked with a known and
consistent quantity of the analyte. MDL determinations using spiked
samples may not be appropriate for all gravimetric methods (e.g.,
residue or total suspended solids), but an MDL based on method blanks
can be determined in such instances.
[[Page 386]]
II. Procedure
(1) Estimate the initial MDL using one or more of the following:
(a) The mean determined concentration plus three times the standard
deviation of a set of method blanks.
(b) The concentration value that corresponds to an instrument
signal-to-noise ratio in the range of 3 to 5.
(c) The concentration equivalent to three times the standard
deviation of replicate instrumental measurements of spiked blanks.
(d) That region of the calibration where there is a significant
change in sensitivity, i.e., a break in the slope of the calibration.
(e) Instrumental limitations.
(f) Previously determined MDL.
Note: It is recognized that the experience of the analyst is
important to this process. However, the analyst should include some or
all of the above considerations in the initial estimate of the MDL.
(2) Determine the initial MDL.
Note: The Initial MDL is used when the laboratory does not have
adequate data to perform the Ongoing Annual Verification specified in
Section (4), typically when a new method is implemented or if a method
was rarely used in the last 24 months.
(a) Select a spiking level, typically 2--10 times the estimated MDL
in Section 1. Spiking levels in excess of 10 times the estimated
detection limit may be required for analytes with very poor recovery
(e.g., for an analyte with 10% recovery, spiked at 100 micrograms/L,
with mean recovery of 10 micrograms/L; the calculated MDL may be around
3 micrograms/L. Therefore, in this example, the spiking level would be
33 times the MDL, but spiking lower may result in no recovery at all).
(b) Process a minimum of seven spiked samples and seven method blank
samples through all steps of the method. The samples used for the MDL
must be prepared in at least three batches on three separate calendar
dates and analyzed on three separate calendar dates. (Preparation and
analysis may be on the same day.) Existing data may be used, if
compliant with the requirements for at least three batches, and
generated within the last twenty four months. The most recent available
data for method blanks and spiked samples must be used. Statistical
outlier removal procedures should not be used to remove data for the
initial MDL determination, since the total number of observations is
small and the purpose of the MDL procedure is to capture routine method
variability. However, documented instances of gross failures (e.g.,
instrument malfunctions, mislabeled samples, cracked vials) may be
excluded from the calculations, provided that at least seven spiked
samples and seven method blanks are available. (The rationale for
removal of specific outliers must be documented and maintained on file
with the results of the MDL determination.)
(i) If there are multiple instruments that will be assigned the same
MDL, then the sample analyses must be distributed across all of the
instruments.
(ii) A minimum of two spiked samples and two method blank samples
prepared and analyzed on different calendar dates is required for each
instrument. Each analytical batch may contain one spiked sample and one
method blank sample run together. A spiked sample and a method blank
sample may be analyzed in the same batch, but are not required to be.
(iii) The same prepared extract may be analyzed on multiple
instruments so long as the minimum requirement of seven preparations in
at least three separate batches is maintained.
(c) Evaluate the spiking level: If any result for any individual
analyte from the spiked samples does not meet the method qualitative
identification criteria or does not provide a numerical result greater
than zero, then repeat the spiked samples at a higher concentration.
(Qualitative identification criteria are a set of rules or guidelines
for establishing the identification or presence of an analyte using a
measurement system. Qualitative identification does not ensure that
quantitative results for the analyte can be obtained.)
(d) Make all computations as specified in the analytical method and
express the final results in the method-specified reporting units.
(i) Calculate the sample standard deviation (S) of the replicate
spiked sample measurements and the sample standard deviation of the
replicate method blank measurements from all instruments to which the
MDL will be applied.
(ii) Compute the MDLs (the MDL based on spiked samples)
as follows:
MDLS = t(n -1, 1-[alpha] = 0.99)Ss
Where:
MDLs = the method detection limit based on spiked samples
t(n-1, 1-[alpha] = 0.99) = the Student's t-value
appropriate for a single-tailed 99th percentile t statistic
and a standard deviation estimate with n-1 degrees of freedom.
See Addendum Table 1.
Ss = sample standard deviation of the replicate spiked sample
analyses.
(iii) Compute the MDLb (the MDL based on method blanks)
as follows:
(A) If none of the method blanks give numerical results for an
individual analyte, the MDLb does not apply. A numerical
result includes both positive and negative results, including results
below the current MDL, but not results of ``ND'' (not detected) commonly
[[Page 387]]
observed when a peak is not present in chromatographic analysis.
(B) If some (but not all) of the method blanks for an individual
analyte give numerical results, set the MDLb equal to the
highest method blank result. If more than 100 method blanks are
available, set MDLb to the level that is no less than the
99th percentile of the method blank results. For ``n'' method blanks
where n = 100, sort the method blanks in rank order. The (n *
0.99) ranked method blank result (round to the nearest whole number) is
the MDLb. For example, to find MDLb from a set of
164 method blanks where the highest ranked method blank results are . .
. 1.5, 1.7, 1.9, 5.0, and 10, then 164 x 0.99 = 162.36 which rounds to
the 162nd method blank result. Therefore, MDLb is 1.9 for n =
164 (10 is the 164th result, 5.0 is the 163rd result, and 1.9 is the
162nd result). Alternatively, you may use spreadsheet algorithms to
calculate the 99th percentile to interpolate between the ranks more
precisely.
(C) If all of the method blanks for an individual analyte give
numerical results, then calculate the MDLb as:
MDLb = X + tn-1,1-[alpha] = (0.99)Sb
Where:
MDLb = the MDL based on method blanks
X = mean of the method blank results (use zero in place of the mean if
the mean is negative)
t(n-1, 1[alpha] = 0.99) = the Student's t-value
appropriate for the single-tailed 99th percentile t statistic
and a standard deviation estimate with n-1 degrees of freedom.
See Addendum Table 1.
Sb = sample standard deviation of the replicate method blank
sample analyses.
Note: If 100 or more method blanks are available, as an option,
MDLb may be set to the concentration that is greater than or
equal to the 99th percentile of the method blank results, as described
in Section (2)(d)(iii)(B).
(e) Select the greater of MDLs or MDLb as the
initial MDL.
(3) Ongoing Data Collection.
(a) During any quarter in which samples are being analyzed, prepare
and analyze a minimum of two spiked samples on each instrument, in
separate batches, using the same spiking concentration used in Section
2. If any analytes are repeatedly not detected in the quarterly spiked
sample analyses, or do not meet the qualitative identification criteria
of the method (see section 2(c) of this procedure), then this is an
indication that the spiking level is not high enough and should be
adjusted upward. Note that it is not necessary to analyze additional
method blanks together with the spiked samples, the method blank
population should include all of the routine method blanks analyzed with
each batch during the course of sample analysis.
(b) Ensure that at least seven spiked samples and seven method
blanks are completed for the annual verification. If only one instrument
is in use, a minimum of seven spikes are still required, but they may be
drawn from the last two years of data collection.
(c) At least once per year, re-evaluate the spiking level.
(i) If more than 5% of the spiked samples do not return positive
numerical results that meet all method qualitative identification
criteria, then the spiking level must be increased and the initial MDL
re-determined following the procedure in section 2.
(ii) [Reserved]
(d) If the method is altered in a way that can be reasonably
expected to change its sensitivity, then re-determine the initial MDL
according to section 2, and the restart the ongoing data collection.
(e) If a new instrument is added to a group of instruments whose
data are being pooled to create a single MDL, analyze a minimum of two
spiked replicates and two method blank replicates on the new instrument.
If both method blank results are below the existing MDL, then the
existing MDLb is validated. Combine the new spiked sample
results to the existing spiked sample results and recalculate the
MDLs as in Section 4. If the recalculated MDLs
does not vary by more than the factor specified in section 4(f) of this
procedure, then the existing MDLs is validated. If either of
these two conditions is not met, then calculate a new MDL following the
instructions in section 2.
(4) Ongoing Annual Verification.
(a) At least once every thirteen months, re-calculate
MDLs and MDLb from the collected spiked samples
and method blank results using the equations in section 2.
(b) Include data generated within the last twenty four months, but
only data with the same spiking level. Only documented instances of
gross failures (e.g., instrument malfunctions, mislabeled samples,
cracked vials) may be excluded from the calculations. (The rationale for
removal of specific outliers must be documented and maintained on file
with the results of the MDL determination.) If the laboratory believes
the sensitivity of the method has changed significantly, then the most
recent data available may be used, maintaining compliance with the
requirement for at least seven replicates in three separate batches on
three separate days (see section 2b).
(c) Include the initial MDL spiked samples, if the data were
generated within twenty four months.
(d) Only use data associated with acceptable calibrations and batch
QC. Include all routine data, with the exception of batches that are
rejected and the associated samples reanalyzed. If the method has been
altered in a way that can be reasonably expected to
[[Page 388]]
change its sensitivity, then use only data collected after the change.
(e) Ideally, use all method blank results from the last 24 months
for the MDLb calculation. The laboratory has the option to
use only the last six months of method blank data or the fifty most
recent method blanks, whichever criteria yields the greater number of
method blanks.
(f) The verified MDL is the greater of the MDLs or
MDLb. If the verified MDL is within 0.5 to 2.0 times the
existing MDL, and fewer than 3% of the method blank results (for the
individual analyte) have numerical results above the existing MDL, then
the existing MDL may optionally be left unchanged. Otherwise, adjust the
MDL to the new verification MDL. (The range of 0.5 to 2.0 approximates
the 95th percentile confidence interval for the initial MDL
determination with six degrees of freedom.)
Addendum to Section II: Determination of the MDL for a Specific Matrix
The MDL may be determined in a specific sample matrix as well as in
reagent water.
(1) Analyze the sample matrix to determine the native (background)
concentration of the analyte(s) of interest.
(2) If the response for the native concentration is at a signal-to-
noise ratio of approximately 5-20, determine the matrix-specific MDL
according to Section 2 but without spiking additional analyte.
(3) Calculate MDLb using the method blanks, not the
sample matrix.
(4) If the signal-to-noise ratio is less than 5, then the analyte(s)
should be spiked into the sample matrix to obtain a concentration that
will give results with a signal-to-noise ratio of approximately 10-20.
(5) If the analytes(s) of interest have signal-to-noise ratio(s)
greater than approximately 20, then the resulting MDL is likely to be
biased high.
Table 1--Single-Tailed 99th Percentile t Statistic
------------------------------------------------------------------------
Degrees of
Number of replicates freedom (n-1) t (n-1, 0.99)
------------------------------------------------------------------------
7....................................... 6 3.143
8....................................... 7 2.998
9....................................... 8 2.896
10...................................... 9 2.821
11...................................... 10 2.764
16...................................... 15 2.602
21...................................... 20 2.528
26...................................... 25 2.485
31...................................... 30 2.457
32...................................... 31 2.453
48...................................... 47 2.408
50...................................... 49 2.405
61...................................... 60 2.390
64...................................... 63 2.387
80...................................... 79 2.374
96...................................... 95 2.366
100..................................... 99 2.365
------------------------------------------------------------------------
III. Documentation
The analytical method used must be specifically identified by number
or title and the MDL for each analyte expressed in the appropriate
method reporting units. Data and calculations used to establish the MDL
must be able to be reconstructed upon request. The sample matrix used to
determine the MDL must also be identified with MDL value. Document the
mean spiked and recovered analyte levels with the MDL. The rationale for
removal of outlier results, if any, must be documented and maintained on
file with the results of the MDL determination.
[82 FR 40939, Aug. 28, 2017]
Sec. Appendix C to Part 136--Determination of Metals and Trace Elements
in Water and Wastes by Inductively Coupled Plasma-Atomic Emission
Spectrometry Method 200.7
1.0 Scope and Application
1.1 Inductively coupled plasma-atomic emission spectrometry (ICP-
AES) is used to determine metals and some nonmetals in solution. This
method is a consolidation of existing methods for water, wastewater, and
solid wastes.1-4 (For analysis of petroleum products see
References 5 and 6, Section 16.0). This method is applicable to the
following analytes:
[[Page 389]]
------------------------------------------------------------------------
Chemical abstract
Analyte services registry
number (CASRN)
------------------------------------------------------------------------
Aluminum (Al)..................................... 7429-90-5
Antimony (Sb)..................................... 7440-36-0
Arsenic (As)...................................... 7440-38-2
Barium (Ba)....................................... 7440-39-3
Beryllium (Be).................................... 7440-41-7
Boron (B)......................................... 7440-42-8
Cadmium (Cd)...................................... 7440-43-9
Calcium (Ca)...................................... 7440-70-2
Cerium \a\ (Cr)................................... 7440-45-1
Chromium (Cr)..................................... 7440-47-3
Cobalt (Co)....................................... 7440-48-4
Copper (Cu)....................................... 7440-50-8
Iron (Fe)......................................... 7439-89-6
Lead (Pb)......................................... 7439-92-1
Lithium (Li)...................................... 7439-93-2
Magnesium (Mg).................................... 7439-95-4
Manganese (Mn).................................... 7439-96-5
Mercury (Hg)...................................... 7439-97-6
Molybdenum (Mo)................................... 7439-98-7
Nickel (Ni)....................................... 7440-02-0
Phosphorus (P).................................... 7723-14-0
Potassium (K)..................................... 7440-09-7
Selenium (Se)..................................... 7782-49-2
Silica \b\ (Si02)................................. 7631-86-9
Silver (Ag)....................................... 7440-22-4
Sodium (Na)....................................... 7440-23-5
Strontium (Sr).................................... 7440-24-6
Thallium (Tl)..................................... 7440-28-0
Tin (Sn).......................................... 7440-31-5
Titanium (Ti)..................................... 7440-32-6
Vanadium (V)...................................... 7440-62-2
Zinc (Zn)......................................... 7440-66-6
------------------------------------------------------------------------
\a\ Cerium has been included as method analyte for correction of
potential interelement spectral interference.
\b\ This method is not suitable for the determination of silica in
solids.
1.2 For reference where this method is approved for use in
compliance monitoring programs [e.g., Clean Water Act (NPDES) or Safe
Drinking Water Act (SDWA)] consult both the appropriate sections of the
Code of Federal Regulation (40 CFR Part 136 Table 1B for NPDES, and Part
141 Sec. 141.23 for drinking water), and the latest Federal Register
announcements.
1.3 ICP-AES can be used to determine dissolved analytes in aqueous
samples after suitable filtration and acid preservation. To reduce
potential interferences, dissolved solids should be <0.2% (w/v) (Section
4.2).
1.4 With the exception of silver, where this method is approved for
the determination of certain metal and metalloid contaminants in
drinking water, samples may be analyzed directly by pneumatic
nebulization without acid digestion if the sample has been properly
preserved with acid and has turbidity of <1 NTU at the time of analysis.
This total recoverable determination procedure is referred to as
``direct analysis''. However, in the determination of some primary
drinking water metal contaminants, preconcentration of the sample may be
required prior to analysis in order to meet drinking water acceptance
performance criteria (Sections 11.2.2 through 11.2.7).
1.5 For the determination of total recoverable analytes in aqueous
and solid samples a digestion/extraction is required prior to analysis
when the elements are not in solution (e.g., soils, sludges, sediments
and aqueous samples that may contain particulate and suspended solids).
Aqueous samples containing suspended or particulate material 1% (w/v)
should be extracted as a solid type sample.
1.6 When determining boron and silica in aqueous samples, only
plastic, PTFE or quartz labware should be used from time of sample
collection to completion of analysis. For accurate determination of
boron in solid samples only quartz or PTFE beakers should be used during
acid extraction with immediate transfer of an extract aliquot to a
plastic centrifuge tube following dilution of the extract to volume.
When possible, borosilicate glass should be avoided to prevent
contamination of these analytes.
1.7 Silver is only slightly soluble in the presence of chloride
unless there is a sufficient chloride concentration to form the soluble
chloride complex. Therefore, low recoveries of silver may occur in
samples, fortified sample matrices and even fortified blanks if
determined as a dissolved analyte or by ``direct analysis'' where the
sample has not been processed using the total recoverable mixed acid
digestion. For this reason it is recommended that samples be digested
prior to the determination of silver. The total recoverable sample
digestion procedure given in this method is suitable for the
determination of silver in aqueous samples containing concentrations up
to 0.1 mg/L. For the analysis of wastewater samples containing higher
concentrations of silver, succeeding smaller volume, well mixed aliquots
should be prepared until the analysis solution contains <0.1 mg/L
silver. The extraction of solid samples containing concentrations of
silver 50 mg/kg should be treated in a similar manner. Also,
the extraction of tin from solid samples should be prepared again using
aliquots <1 g when determined sample concentrations exceed 1%.
1.8 The total recoverable sample digestion procedure given in this
method will solubilize and hold in solution only minimal concentrations
of barium in the presence of free sulfate. For the analysis of barium in
samples having varying and unknown concentrations of sulfate, analysis
should be completed as soon as possible after sample preparation.
1.9 The total recoverable sample digestion procedure given in this
method is not suitable for the determination of volatile organo-mercury
compounds. However, if digestion is not required (turbidity <1 NTU), the
combined concentrations of inorganic and organo-mercury in solution can
be determined by ``direct analysis'' pneumatic nebulization provided the
sample solution is adjusted to contain the same mixed acid
[[Page 390]]
(HNO3 + HCl) matrix as the total recoverable calibration
standards and blank solutions.
1.10 Detection limits and linear ranges for the elements will vary
with the wavelength selected, the spectrometer, and the matrices. Table
1 provides estimated instrument detection limits for the listed
wavelengths.\7\ However, actual method detection limits and linear
working ranges will be dependent on the sample matrix, instrumentation,
and selected operating conditions.
1.11 Users of the method data should state the data-quality
objectives prior to analysis. Users of the method must document and have
on file the required initial demonstration performance data described in
Section 9.2 prior to using the method for analysis.
2.0 Summary of Method
2.1 An aliquot of a well mixed, homogeneous aqueous or solid sample
is accurately weighed or measured for sample processing. For total
recoverable analysis of a solid or an aqueous sample containing
undissolved material, analytes are first solubilized by gentle refluxing
with nitric and hydrochloric acids. After cooling, the sample is made up
to volume, is mixed and centrifuged or allowed to settle overnight prior
to analysis. For the determination of dissolved analytes in a filtered
aqueous sample aliquot, or for the ``direct analysis'' total recoverable
determination of analytes in drinking water where sample turbidity is <1
NTU, the sample is made ready for analysis by the appropriate addition
of nitric acid, and then diluted to a predetermined volume and mixed
before analysis.
2.2 The analysis described in this method involves multielemental
determinations by ICP-AES using sequential or simultaneous instruments.
The instruments measure characteristic atomic-line emission spectra by
optical spectrometry. Samples are nebulized and the resulting aerosol is
transported to the plasma torch. Element specific emission spectra are
produced by a radio-frequency inductively coupled plasma. The spectra
are dispersed by a grating spectrometer, and the intensities of the line
spectra are monitored at specific wavelengths by a photosensitive
device. Photocurrents from the photosensitive device are processed and
controlled by a computer system. A background correction technique is
required to compensate for variable background contribution to the
determination of the analytes. Background must be measured adjacent to
the analyte wavelength during analysis. Various interferences must be
considered and addressed appropriately as discussed in Sections 4.0,
7.0, 9.0, 10.0, and 11.0.
3.0 Definitions
3.1 Calibration Blank--A volume of reagent water acidified with the
same acid matrix as in the calibration standards. The calibration blank
is a zero standard and is used to calibrate the ICP instrument (Section
7.10.1).
3.2 Calibration Standard (CAL)--A solution prepared from the
dilution of stock standard solutions. The CAL solutions are used to
calibrate the instrument response with respect to analyte concentration
(Section 7.9).
3.3 Dissolved Analyte--The concentration of analyte in an aqueous
sample that will pass through a 0.45 [micro]m membrane filter assembly
prior to sample acidification (Section 11.1).
3.4 Field Reagent Blank (FRB)--An aliquot of reagent water or other
blank matrix that is placed in a sample container in the laboratory and
treated as a sample in all respects, including shipment to the sampling
site, exposure to the sampling site conditions, storage, preservation,
and all analytical procedures. The purpose of the FRB is to determine if
method analytes or other interferences are present in the field
environment (Section 8.5).
3.5 Instrument Detection Limit (IDL)--The concentration equivalent
to the analyte signal which is equal to three times the standard
deviation of a series of 10 replicate measurements of the calibration
blank signal at the same wavelength (Table 1.).
3.6 Instrument Performance Check (IPC) Solution--A solution of
method analytes, used to evaluate the performance of the instrument
system with respect to a defined set of method criteria (Sections 7.11
and 9.3.4).
3.7 Internal Standard--Pure analyte(s) added to a sample, extract,
or standard solution in known amount(s) and used to measure the relative
responses of other method analytes that are components of the same
sample or solution. The internal standard must be an analyte that is not
a sample component (Section 11.5).
3.8 Laboratory Duplicates (LD1 and LD2)--Two aliquots of the same
sample taken in the laboratory and analyzed separately with identical
procedures. Analyses of LD1 and LD2 indicate precision associated with
laboratory procedures, but not with sample collection, preservation, or
storage procedures.
3.9 Laboratory Fortified Blank (LFB)--An aliquot of LRB to which
known quantities of the method analytes are added in the laboratory. The
LFB is analyzed exactly like a sample, and its purpose is to determine
whether the methodology is in control and whether the laboratory is
capable of making accurate and precise measurements (Sections 7.10.3 and
9.3.2).
3.10 Laboratory Fortified Sample Matrix (LFM)--An aliquot of an
environmental sample to which known quantities of the method analytes
are added in the laboratory. The
[[Page 391]]
LFM is analyzed exactly like a sample, and its purpose is to determine
whether the sample matrix contributes bias to the analytical results.
The background concentrations of the analytes in the sample matrix must
be determined in a separate aliquot and the measured values in the LFM
corrected for background concentrations (Section 9.4).
3.11 Laboratory Reagent Blank (LRB)--An aliquot of reagent water or
other blank matrices that are treated exactly as a sample including
exposure to all glassware, equipment, solvents, reagents, and internal
standards that are used with other samples. The LRB is used to determine
if method analytes or other interferences are present in the laboratory
environment, reagents, or apparatus (Sections 7.10.2 and 9.3.1).
3.12 Linear Dynamic Range (LDR)--The concentration range over which
the instrument response to an analyte is linear (Section 9.2.2).
3.13 Method Detection Limit (MDL)--The minimum concentration of an
analyte that can be identified, measured, and reported with 99%
confidence that the analyte concentration is greater than zero (Section
9.2.4 and Table 4.).
3.14 Plasma Solution--A solution that is used to determine the
optimum height above the work coil for viewing the plasma (Sections 7.15
and 10.2.3).
3.15 Quality Control Sample (QCS)--A solution of method analytes of
known concentrations which is used to fortify an aliquot of LRB or
sample matrix. The QCS is obtained from a source external to the
laboratory and different from the source of calibration standards. It is
used to check either laboratory or instrument performance (Sections 7.12
and 9.2.3).
3.16 Solid Sample--For the purpose of this method, a sample taken
from material classified as soil, sediment or sludge.
3.17 Spectral Interference Check (SIC) Solution--A solution of
selected method analytes of higher concentrations which is used to
evaluate the procedural routine for correcting known interelement
spectral interferences with respect to a defined set of method criteria
(Sections 7.13, 7.14 and 9.3.5).
3.18 Standard Addition--The addition of a known amount of analyte to
the sample in order to determine the relative response of the detector
to an analyte within the sample matrix. The relative response is then
used to assess either an operative matrix effect or the sample analyte
concentration (Sections 9.5.1 and 11.5).
3.19 Stock Standard Solution--A concentrated solution containing one
or more method analytes prepared in the laboratory using assayed
reference materials or purchased from a reputable commercial source
(Section 7.8).
3.20 Total Recoverable Analyte--The concentration of analyte
determined either by ``direct analysis'' of an unfiltered acid preserved
drinking water sample with turbidity of <1 NTU (Section 11.2.1), or by
analysis of the solution extract of a solid sample or an unfiltered
aqueous sample following digestion by refluxing with hot dilute mineral
acid(s) as specified in the method (Sections 11.2 and 11.3).
3.21 Water Sample--For the purpose of this method, a sample taken
from one of the following sources: drinking, surface, ground, storm
runoff, industrial or domestic wastewater.
4.0 Interferences
4.1 Spectral interferences are caused by background emission from
continuous or recombination phenomena, stray light from the line
emission of high concentration elements, overlap of a spectral line from
another element, or unresolved overlap of molecular band spectra.
4.1.1 Background emission and stray light can usually be compensated
for by subtracting the background emission determined by measurement(s)
adjacent to the analyte wavelength peak. Spectral scans of samples or
single element solutions in the analyte regions may indicate not only
when alternate wavelengths are desirable because of severe spectral
interference, but also will show whether the most appropriate estimate
of the background emission is provided by an interpolation from
measurements on both sides of the wavelength peak or by the measured
emission on one side or the other. The location(s) selected for the
measurement of background intensity will be determined by the complexity
of the spectrum adjacent to the wavelength peak. The location(s) used
for routine measurement must be free of off-line spectral interference
(interelement or molecular) or adequately corrected to reflect the same
change in background intensity as occurs at the wavelength peak.
4.1.2 Spectral overlaps may be avoided by using an alternate
wavelength or can be compensated for by equations that correct for
interelement contributions, which involves measuring the interfering
elements. Some potential on-line spectral interferences observed for the
recommended wavelengths are given in Table 2. When operative and
uncorrected, these interferences will produce false-positive
determinations and be reported as analyte concentrations. The
interferences listed are only those that occur between method analytes.
Only interferences of a direct overlap nature that were observed with a
single instrument having a working resolution of 0.035 nm are listed.
More extensive information on interferant effects at various wavelengths
and resolutions is available in Boumans' Tables.\8\ Users may apply
interelement correction factors determined on their instruments within
tested concentration ranges to compensate (off-line or
[[Page 392]]
on-line) for the effects of interfering elements.
4.1.3 When interelement corrections are applied, there is a need to
verify their accuracy by analyzing spectral interference check solutions
as described in Section 7.13. Interelement corrections will vary for the
same emission line among instruments because of differences in
resolution, as determined by the grating plus the entrance and exit slit
widths, and by the order of dispersion. Interelement corrections will
also vary depending upon the choice of background correction points.
Selecting a background correction point where an interfering emission
line may appear should be avoided when practical. Interelement
corrections that constitute a major portion of an emission signal may
not yield accurate data. Users should not forget that some samples may
contain uncommon elements that could contribute spectral
interferences.\7 8\
4.1.4 The interference effects must be evaluated for each individual
instrument whether configured as a sequential or simultaneous
instrument. For each instrument, intensities will vary not only with
optical resolution but also with operating conditions (such as power,
viewing height and argon flow rate). When using the recommended
wavelengths given in Table 1, the analyst is required to determine and
document for each wavelength the effect from the known interferences
given in Table 2, and to utilize a computer routine for their automatic
correction on all analyses. To determine the appropriate location for
off-line background correction, the user must scan the area on either
side adjacent to the wavelength and record the apparent emission
intensity from all other method analytes. This spectral information must
be documented and kept on file. The location selected for background
correction must be either free of off-line interelement spectral
interference or a computer routine must be used for their automatic
correction on all determinations. If a wavelength other than the
recommended wavelength is used, the user must determine and document
both the on-line and off-line spectral interference effect from all
method analytes and provide for their automatic correction on all
analyses. Tests to determine the spectral interference must be done
using analyte concentrations that will adequately describe the
interference. Normally, 100 mg/L single element solutions are
sufficient, however, for analytes such as iron that may be found at high
concentration a more appropriate test would be to use a concentration
near the upper LDR limit. See Section 10.4 for required spectral
interference test criteria.
4.1.5 When interelement corrections are not used, either on-going
SIC solutions (Section 7.14) must be analyzed to verify the absence of
interelement spectral interference or a computer software routine must
be employed for comparing the determinative data to limits files for
notifying the analyst when an interfering element is detected in the
sample at a concentration that will produce either an apparent false
positive concentration, greater than the analyte IDL, or false negative
analyte concentration, less than the 99% lower control limit of the
calibration blank. When the interference accounts for 10% or more of the
analyte concentration, either an alternate wavelength free of
interference or another approved test procedure must be used to complete
the analysis. For example, the copper peak at 213.853 nm could be
mistaken for the zinc peak at 213.856 nm in solutions with high copper
and low zinc concentrations. For this example, a spectral scan in the
213.8 nm region would not reveal the misidentification because a single
peak near the zinc location would be observed. The possibility of this
misidentification of copper for the zinc peak at 213.856 nm can be
identified by measuring the copper at another emission line, e.g.,
324.754 nm. Users should be aware that, depending upon the instrumental
resolution, alternate wavelengths with adequate sensitivity and freedom
from interference may not be available for all matrices. In these
circumstances the analyte must be determined using another approved test
procedure.
4.2 Physical interferences are effects associated with the sample
nebulization and transport processes. Changes in viscosity and surface
tension can cause significant inaccuracies, especially in samples
containing high dissolved solids or high acid concentrations. If
physical interferences are present, they must be reduced by such means
as a high-solids nebulizer, diluting the sample, using a peristaltic
pump, or using an appropriate internal standard element. Another problem
that can occur with high dissolved solids is salt buildup at the tip of
the nebulizer, which affects aerosol flow rate and causes instrumental
drift. This problem can be controlled by a high-solids nebulizer,
wetting the argon prior to nebulization, using a tip washer, or diluting
the sample. Also, it has been reported that better control of the argon
flow rates, especially for the nebulizer, improves instrument stability
and precision; this is accomplished with the use of mass flow
controllers.
4.3 Chemical interferences include molecular-compound formation,
ionization effects, and solute-vaporization effects. Normally, these
effects are not significant with the ICP-AES technique. If observed,
they can be minimized by careful selection of operating conditions (such
as incident power and observation height), by buffering of the sample,
by matrix matching, and by standard-addition
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procedures. Chemical interferences are highly dependent on matrix type
and the specific analyte element.
4.4 Memory interferences result when analytes in a previous sample
contribute to the signals measured in a new sample. Memory effects can
result from sample deposition on the uptake tubing to the nebulizer, and
from the buildup of sample material in the plasma torch and spray
chamber. The site where these effects occur is dependent on the element
and can be minimized by flushing the system with a rinse blank between
samples (Section 7.10.4). The possibility of memory interferences should
be recognized within an analytical run and suitable rinse times should
be used to reduce them. The rinse times necessary for a particular
element must be estimated prior to analysis. This may be achieved by
aspirating a standard containing elements corresponding to either their
LDR or a concentration ten times those usually encountered. The
aspiration time should be the same as a normal sample analysis period,
followed by analysis of the rinse blank at designated intervals. The
length of time required to reduce analyte signals to within a factor of
two of the method detection limit, should be noted. Until the required
rinse time is established, this method requires a rinse period of at
least 60 seconds between samples and standards. If a memory interference
is suspected, the sample must be re-analyzed after a long rinse period.
5.0 Safety
5.1 The toxicity or carcinogenicity of each reagent used in this
method have not been fully established. Each chemical should be regarded
as a potential health hazard and exposure to these compounds should be
as low as reasonably achievable. Each laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method.9-12
A reference file of material data handling sheets should also be made
available to all personnel involved in the chemical analysis.
Specifically, concentrated nitric and hydrochloric acids present various
hazards and are moderately toxic and extremely irritating to skin and
mucus membranes. Use these reagents in a fume hood whenever possible and
if eye or skin contact occurs, flush with large volumes of water. Always
wear safety glasses or a shield for eye protection, protective clothing
and observe proper mixing when working with these reagents.
5.2 The acidification of samples containing reactive materials may
result in the release of toxic gases, such as cyanides or sulfides.
Acidification of samples should be done in a fume hood.
5.3 All personnel handling environmental samples known to contain or
to have been in contact with human waste should be immunized against
known disease causative agents.
5.4 The inductively coupled plasma should only be viewed with proper
eye protection from the ultraviolet emissions.
5.5 It is the responsibility of the user of this method to comply
with relevant disposal and waste regulations. For guidance see Sections
14.0 and 15.0.
6.0 Equipment and Supplies
6.1 Inductively coupled plasma emission spectrometer:
6.1.1 Computer-controlled emission spectrometer with background-
correction capability.
The spectrometer must be capable of meeting and complying with the
requirements described and referenced in Section 2.2.
6.1.2 Radio-frequency generator compliant with FCC regulations.
6.1.3 Argon gas supply--High purity grade (99.99%). When analyses
are conducted frequently, liquid argon is more economical and requires
less frequent replacement of tanks than compressed argon in conventional
cylinders.
6.1.4 A variable speed peristaltic pump is required to deliver both
standard and sample solutions to the nebulizer.
6.1.5 (Optional) Mass flow controllers to regulate the argon flow
rates, especially the aerosol transport gas, are highly recommended.
Their use will provide more exacting control of reproducible plasma
conditions.
6.2 Analytical balance, with capability to measure to 0.1 mg, for
use in weighing solids, for preparing standards, and for determining
dissolved solids in digests or extracts.
6.3 A temperature adjustable hot plate capable of maintaining a
temperature of 95 [deg]C.
6.4 (Optional) A temperature adjustable block digester capable of
maintaining a temperature of 95 [deg]C and equipped with 250 mL
constricted digestion tubes.
6.5 (Optional) A steel cabinet centrifuge with guard bowl, electric
timer and brake.
6.6 A gravity convection drying oven with thermostatic control
capable of maintaining 180 [deg]C 5 [deg]C.
6.7 (Optional) An air displacement pipetter capable of delivering
volumes ranging from 0.1-2500 [micro]L with an assortment of high
quality disposable pipet tips.
6.8 Mortar and pestle, ceramic or nonmetallic material.
6.9 Polypropylene sieve, 5-mesh (4 mm opening).
6.10 Labware--For determination of trace levels of elements,
contamination and loss are of prime consideration. Potential
contamination sources include improperly cleaned laboratory apparatus
and general
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contamination within the laboratory environment from dust, etc. A clean
laboratory work area designated for trace element sample handling must
be used. Sample containers can introduce positive and negative errors in
the determination of trace elements by contributing contaminants through
surface desorption or leaching, or depleting element concentrations
through adsorption processes. All reusable labware (glass, quartz,
polyethylene, PTFE, FEP, etc.) should be sufficiently clean for the task
objectives. Several procedures found to provide clean labware include
washing with a detergent solution, rinsing with tap water, soaking for
four hours or more in 20% (v/v) nitric acid or a mixture of
HNO3 and HCl (1 + 2 + 9), rinsing with reagent water and
storing clean. \2 3\ Chromic acid cleaning solutions must be avoided
because chromium is an analyte.
6.10.1 Glassware--Volumetric flasks, graduated cylinders, funnels
and centrifuge tubes (glass and/or metal-free plastic).
6.10.2 Assorted calibrated pipettes.
6.10.3 Conical Phillips beakers (Corning 1080-250 or equivalent),
250 mL with 50 mm watch glasses.
6.10.4 Griffin beakers, 250 mL with 75 mm watch glasses and
(optional) 75 mm ribbed watch glasses.
6.10.5 (Optional) PTFE and/or quartz Griffin beakers, 250 mL with
PTFE covers.
6.10.6 Evaporating dishes or high-form crucibles, porcelain, 100 mL
capacity.
6.10.7 Narrow-mouth storage bottles, FEP (fluorinated ethylene
propylene) with screw closure, 125 mL to 1 L capacities.
6.10.8 One-piece stem FEP wash bottle with screw closure, 125 mL
capacity.
7.0 Reagents and Standards
7.1 Reagents may contain elemental impurities which might affect
analytical data. Only high-purity reagents that conform to the American
Chemical Society specifications \13\ should be used whenever possible.
If the purity of a reagent is in question, analyze for contamination.
All acids used for this method must be of ultra high-purity grade or
equivalent. Suitable acids are available from a number of manufacturers.
Redistilled acids prepared by sub-boiling distillation are acceptable.
7.2 Hydrochloric acid, concentrated (sp.gr. 1.19)--HCl.
7.2.1 Hydrochloric acid (1 + 1)--Add 500 mL concentrated HCl to 400
mL reagent water and dilute to 1 L.
7.2.2 Hydrochloric acid (1 + 4)--Add 200 mL concentrated HCl to 400
mL reagent water and dilute to 1 L.
7.2.3 Hydrochloric acid (1 + 20)--Add 10 mL concentrated HCl to 200
mL reagent water.
7.3 Nitric acid, concentrated (sp.gr. 1.41)--HNO3.
7.3.1 Nitric acid (1 + 1)--Add 500 mL concentrated HNO3
to 400 mL reagent water and dilute to 1 L.
7.3.2 Nitric acid (1 + 2)--Add 100 mL concentrated HNO3
to 200 mL reagent water.
7.3.3 Nitric acid (1 + 5)--Add 50 mL concentrated HNO3 to
250 mL reagent water.
7.3.4 Nitric acid (1 + 9)--Add 10 mL concentrated HNO3 to
90 mL reagent water.
7.4 Reagent water. All references to water in this method refer to
ASTM Type I grade water.\14\
7.5 Ammonium hydroxide, concentrated (sp.gr. 0.902).
7.6 Tartaric acid, ACS reagent grade.
7.7 Hydrogen peroxide, 50%, stabilized certified reagent grade.
7.8 Standard Stock Solutions--Stock standards may be purchased or
prepared from ultra-high purity grade chemicals (99.99-99.999% pure).
All compounds must be dried for one hour at 105 [deg]C, unless otherwise
specified. It is recommended that stock solutions be stored in FEP
bottles. Replace stock standards when succeeding dilutions for
preparation of calibration standards cannot be verified.
CAUTION: Many of these chemicals are extremely toxic if inhaled or
swallowed (Section 5.1). Wash hands thoroughly after handling.
Typical stock solution preparation procedures follow for 1 L
quantities, but for the purpose of pollution prevention, the analyst is
encouraged to prepare smaller quantities when possible. Concentrations
are calculated based upon the weight of the pure element or upon the
weight of the compound multiplied by the fraction of the analyte in the
compound
From pure element,
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[GRAPHIC] [TIFF OMITTED] TR18MY12.001
where: gravimetric factor = the weight fraction of the analyte in the
compound
7.8.1 Aluminum solution, stock, 1 mL = 1000 [micro]g Al: Dissolve
1.000 g of aluminum metal, weighed accurately to at least four
significant figures, in an acid mixture of 4.0 mL of (1 + 1) HCl and 1
mL of concentrated HNO3 in a beaker. Warm beaker slowly to
effect solution. When dissolution is complete, transfer solution
quantitatively to a 1 L flask, add an additional 10.0 mL of (1 + 1) HCl
and dilute to volume with reagent water.
7.8.2 Antimony solution, stock, 1 mL = 1000 [micro]g Sb: Dissolve
1.000 g of antimony powder, weighed accurately to at least four
significant figures, in 20.0 mL (1 + 1) HNO3 and 10.0 mL
concentrated HCl. Add 100 mL reagent water and 1.50 g tartaric acid.
Warm solution slightly to effect complete dissolution. Cool solution and
add reagent water to volume in a 1 L volumetric flask.
7.8.3 Arsenic solution, stock, 1 mL = 1000 [micro]g As: Dissolve
1.320 g of As2O3 (As fraction = 0.7574), weighed
accurately to at least four significant figures, in 100 mL of reagent
water containing 10.0 mL concentrated NH4OH. Warm the
solution gently to effect dissolution. Acidify the solution with 20.0 mL
concentrated HNO3 and dilute to volume in a 1 L volumetric
flask with reagent water.
7.8.4 Barium solution, stock, 1 mL = 1000 [micro]g Ba: Dissolve
1.437 g BaCO3 (Ba fraction = 0.6960), weighed accurately to
at least four significant figures, in 150 mL (1 + 2) HNO3
with heating and stirring to degas and dissolve compound. Let solution
cool and dilute with reagent water in 1 L volumetric flask.
7.8.5 Beryllium solution, stock, 1 mL = 1000 [micro]g Be: DO NOT
DRY. Dissolve 19.66 g BeSO44H2O (Be
fraction = 0.0509), weighed accurately to at least four significant
figures, in reagent water, add 10.0 mL concentrated HNO3, and
dilute to volume in a 1 L volumetric flask with reagent water.
7.8.6 Boron solution, stock, 1 mL = 1000 [micro]g B: DO NOT DRY.
Dissolve 5.716 g anhydrous H3BO3 (B fraction =
0.1749), weighed accurately to at least four significant figures, in
reagent water and dilute in a 1 L volumetric flask with reagent water.
Transfer immediately after mixing to a clean FEP bottle to minimize any
leaching of boron from the glass volumetric container. Use of a nonglass
volumetric flask is recommended to avoid boron contamination from
glassware.
7.8.7 Cadmium solution, stock, 1 mL = 1000 [micro]g Cd: Dissolve
1.000 g Cd metal, acid cleaned with (1 + 9) HNO3, weighed
accurately to at least four significant figures, in 50 mL (1 + 1)
HNO3 with heating to effect dissolution. Let solution cool
and dilute with reagent water in a 1 L volumetric flask.
7.8.8 Calcium solution, stock, 1 mL = 1000 [micro]g Ca: Suspend
2.498 g CaCO3 (Ca fraction = 0.4005), dried at 180 [deg]C for
one hour before weighing, weighed accurately to at least four
significant figures, in reagent water and dissolve cautiously with a
minimum amount of (1 + 1) HNO3. Add 10.0 mL concentrated
HNO3 and dilute to volume in a 1 L volumetric flask with
reagent water.
7.8.9 Cerium solution, stock, 1 mL = 1000 [micro]g Ce: Slurry 1.228
g CeO2 (Ce fraction = 0.8141), weighed accurately to at least
four significant figures, in 100 mL concentrated HNO3 and
evaporate to dryness. Slurry the residue in 20 mL H2O, add 50
mL concentrated HNO3, with heat and stirring add 60 mL 50%
H2O2 dropwise in 1 mL increments allowing periods
of stirring between the 1 mL additions. Boil off excess
H2O2 before diluting to volume in a 1 L volumetric
flask with reagent water.
7.8.10 Chromium solution, stock, 1 mL = 1000 [micro]g Cr: Dissolve
1.923 g CrO3 (Cr fraction = 0.5200), weighed accurately to at
least four significant figures, in 120 mL (1 + 5) HNO3. When
solution is complete, dilute to volume in a 1 L volumetric flask with
reagent water.
7.8.11 Cobalt solution, stock, 1 mL = 1000 [micro]g Co: Dissolve
1.000 g Co metal, acid cleaned with (1 + 9) HNO3, weighed
accurately to at least four significant figures, in 50.0 mL (1 + 1)
HNO3. Let solution cool and dilute to volume in a 1 L
volumetric flask with reagent water.
7.8.12 Copper solution, stock, 1 mL = 1000 [micro]g Cu: Dissolve
1.000 g Cu metal, acid cleaned with (1 + 9) HNO3, weighed
accurately to at least four significant figures, in 50.0 mL (1 + 1)
HNO3 with heating to effect dissolution. Let solution cool
and dilute in a 1 L volumetric flask with reagent water.
7.8.13 Iron solution, stock, 1 mL = 1000 [micro]g Fe: Dissolve 1.000
g Fe metal, acid cleaned
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with (1 + 1) HCl, weighed accurately to four significant figures, in 100
mL (1 + 1) HCl with heating to effect dissolution. Let solution cool and
dilute with reagent water in a 1 L volumetric flask.
7.8.14 Lead solution, stock, 1 mL = 1000 [micro]g Pb: Dissolve 1.599
g Pb(NO3)2 (Pb fraction = 0.6256), weighed
accurately to at least four significant figures, in a minimum amount of
(1 + 1) HNO3. Add 20.0 mL (1 + 1) HNO3 and dilute
to volume in a 1 L volumetric flask with reagent water.
7.8.15 Lithium solution, stock, 1 mL = 1000 [micro]g Li: Dissolve
5.324 g Li2CO3 (Li fraction = 0.1878), weighed
accurately to at least four significant figures, in a minimum amount of
(1 + 1) HCl and dilute to volume in a 1 L volumetric flask with reagent
water.
7.8.16 Magnesium solution, stock, 1 mL = 1000 [micro]g Mg: Dissolve
1.000 g cleanly polished Mg ribbon, accurately weighed to at least four
significant figures, in slowly added 5.0 mL (1 + 1) HCl (CAUTION:
reaction is vigorous). Add 20.0 mL (1 + 1) HNO3 and dilute to
volume in a 1 L volumetric flask with reagent water.
7.8.17 Manganese solution, stock, 1 mL = 1000 [micro]g Mn: Dissolve
1.000 g of manganese metal, weighed accurately to at least four
significant figures, in 50 mL (1 + 1) HNO3 and dilute to
volume in a 1 L volumetric flask with reagent water.
7.8.18 Mercury solution, stock, 1 mL = 1000 [micro]g Hg: DO NOT DRY.
CAUTION: highly toxic element. Dissolve 1.354 g HgCl2 (Hg
fraction = 0.7388) in reagent water. Add 50.0 mL concentrated
HNO3 and dilute to volume in 1 L volumetric flask with
reagent water.
7.8.19 Molybdenum solution, stock, 1 mL = 1000 [micro]g Mo: Dissolve
1.500 g MoO3 (Mo fraction = 0.6666), weighed accurately to at
least four significant figures, in a mixture of 100 mL reagent water and
10.0 mL concentrated NH4OH, heating to effect dissolution.
Let solution cool and dilute with reagent water in a 1 L volumetric
flask.
7.8.20 Nickel solution, stock, 1 mL = 1000 [micro]g Ni: Dissolve
1.000 g of nickel metal, weighed accurately to at least four significant
figures, in 20.0 mL hot concentrated HNO3, cool, and dilute
to volume in a 1 L volumetric flask with reagent water.
7.8.21 Phosphorus solution, stock, 1 mL = 1000 [micro]g P: Dissolve
3.745 g NH4H2PO4 (P fraction = 0.2696),
weighed accurately to at least four significant figures, in 200 mL
reagent water and dilute to volume in a 1 L volumetric flask with
reagent water.
7.8.22 Potassium solution, stock, 1 mL = 1000 [micro]g K: Dissolve
1.907 g KCl (K fraction = 0.5244) dried at 110 [deg]C, weighed
accurately to at least four significant figures, in reagent water, add
20 mL (1 + 1) HCl and dilute to volume in a 1 L volumetric flask with
reagent water.
7.8.23 Selenium solution, stock, 1 mL = 1000 [micro]g Se: Dissolve
1.405 g SeO2 (Se fraction = 0.7116), weighed accurately to at
least four significant figures, in 200 mL reagent water and dilute to
volume in a 1 L volumetric flask with reagent water.
7.8.24 Silica solution, stock, 1 mL = 1000 [micro]g SiO2:
DO NOT DRY. Dissolve 2.964 g
(NH4)2SiF6, weighed accurately to at
least four significant figures, in 200 mL (1 + 20) HCl with heating at
85 [deg]C to effect dissolution. Let solution cool and dilute to volume
in a 1 L volumetric flask with reagent water.
7.8.25 Silver solution, stock, 1 mL = 1000 [micro]g Ag: Dissolve
1.000 g Ag metal, weighed accurately to at least four significant
figures, in 80 mL (1 + 1) HNO3 with heating to effect
dissolution. Let solution cool and dilute with reagent water in a 1 L
volumetric flask. Store solution in amber bottle or wrap bottle
completely with aluminum foil to protect solution from light.
7.8.26 Sodium solution, stock, 1 mL = 1000 [micro]g Na: Dissolve
2.542 g NaCl (Na fraction = 0.3934), weighed accurately to at least four
significant figures, in reagent water. Add 10.0 mL concentrated
HNO3 and dilute to volume in a 1 L volumetric flask with
reagent water.
7.8.27 Strontium solution, stock, 1 mL = 1000 [micro]g Sr: Dissolve
1.685 g SrCO3 (Sr fraction = 0.5935), weighed accurately to
at least four significant figures, in 200 mL reagent water with dropwise
addition of 100 mL (1 + 1) HCl. Dilute to volume in a 1 L volumetric
flask with reagent water.
7.8.28 Thallium solution, stock, 1 mL = 1000 [micro]g Tl: Dissolve
1.303 g TlNO3 (Tl fraction = 0.7672), weighed accurately to
at least four significant figures, in reagent water. Add 10.0 mL
concentrated HNO3 and dilute to volume in a 1 L volumetric
flask with reagent water.
7.8.29 Tin solution, stock, 1 mL = 1000 [micro]g Sn: Dissolve 1.000
g Sn shot, weighed accurately to at least four significant figures, in
an acid mixture of 10.0 mL concentrated HCl and 2.0 mL (1 + 1)
HNO3 with heating to effect dissolution. Let solution cool,
add 200 mL concentrated HCl, and dilute to volume in a 1 L volumetric
flask with reagent water.
7.8.30 Titanium solution, stock, 1 mL = 1000 [micro]g Ti: DO NOT
DRY. Dissolve 6.138 g
(NH4)2TiO(C2O4)2
H2O (Ti fraction = 0.1629), weighed accurately to at least
four significant figures, in 100 mL reagent water. Dilute to volume in a
1 L volumetric flask with reagent water.
7.8.31 Vanadium solution, stock, 1 mL = 1000 [micro]g V: Dissolve
1.000 g V metal, acid cleaned with (1 + 9) HNO3, weighed
accurately to at least four significant figures, in 50 mL (1 + 1)
HNO3 with heating to effect dissolution. Let solution cool
and dilute with reagent water to volume in a 1 L volumetric flask.
7.8.32 Yttrium solution, stock 1 mL = 1000 [micro]g Y: Dissolve
1.270 g Y2O3 (Y fraction = 0.7875), weighed
accurately to at least four significant figures, in 50 mL (1 + 1)
HNO3, heating to effect dissolution. Cool and dilute
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to volume in a 1 L volumetric flask with reagent water.
7.8.33 Zinc solution, stock, 1 mL = 1000 [micro]g Zn: Dissolve 1.000
g Zn metal, acid cleaned with (1 + 9) HNO3, weighed
accurately to at least four significant figures, in 50 mL (1 + 1)
HNO3 with heating to effect dissolution. Let solution cool
and dilute with reagent water to volume in a 1 L volumetric flask.
7.9 Mixed Calibration Standard Solutions--For the analysis of total
recoverable digested samples prepare mixed calibration standard
solutions (see Table 3) by combining appropriate volumes of the stock
solutions in 500 mL volumetric flasks containing 20 mL (1 + 1)
HNO3 and 20 mL (1 + 1) HCl and dilute to volume with reagent
water. Prior to preparing the mixed standards, each stock solution
should be analyzed separately to determine possible spectral
interferences or the presence of impurities. Care should be taken when
preparing the mixed standards to ensure that the elements are compatible
and stable together. To minimize the opportunity for contamination by
the containers, it is recommended to transfer the mixed-standard
solutions to acid-cleaned, never-used FEP fluorocarbon (FEP) bottles for
storage. Fresh mixed standards should be prepared, as needed, with the
realization that concentrations can change on aging. Calibration
standards not prepared from primary standards must be initially verified
using a certified reference solution. For the recommended wavelengths
listed in Table 1 some typical calibration standard combinations are
given in Table 3.
Note: If the addition of silver to the recommended mixed-acid
calibration standard results in an initial precipitation, add 15 mL of
reagent water and warm the flask until the solution clears. For this
acid combination, the silver concentration should be limited to 0.5 mg/
L.
7.10 Blanks--Four types of blanks are required for the analysis. The
calibration blank is used in establishing the analytical curve, the
laboratory reagent blank is used to assess possible contamination from
the sample preparation procedure, the laboratory fortified blank is used
to assess routine laboratory performance and a rinse blank is used to
flush the instrument uptake system and nebulizer between standards,
check solutions, and samples to reduce memory interferences.
7.10.1 The calibration blank for aqueous samples and extracts is
prepared by acidifying reagent water to the same concentrations of the
acids as used for the standards. The calibration blank should be stored
in a FEP bottle.
7.10.2 The laboratory reagent blank (LRB) must contain all the
reagents in the same volumes as used in the processing of the samples.
The LRB must be carried through the same entire preparation scheme as
the samples including sample digestion, when applicable.
7.10.3 The laboratory fortified blank (LFB) is prepared by
fortifying an aliquot of the laboratory reagent blank with all analytes
to a suitable concentration using the following recommended criteria: Ag
0.1 mg/L, K 5.0 mg/L and all other analytes 0.2 mg/L or a concentration
approximately 100 times their respective MDL, whichever is greater. The
LFB must be carried through the same entire preparation scheme as the
samples including sample digestion, when applicable.
7.10.4 The rinse blank is prepared by acidifying reagent water to
the same concentrations of acids as used in the calibration blank and
stored in a convenient manner.
7.11 Instrument Performance Check (IPC) Solution--The IPC solution
is used to periodically verify instrument performance during analysis.
It should be prepared in the same acid mixture as the calibration
standards by combining method analytes at appropriate concentrations.
Silver must be limited to <0.5 mg/L; while potassium and phosphorus
because of higher MDLs and silica because of potential contamination
should be at concentrations of 10 mg/L. For other analytes a
concentration of 2 mg/L is recommended. The IPC solution should be
prepared from the same standard stock solutions used to prepare the
calibration standards and stored in an FEP bottle. Agency programs may
specify or request that additional instrument performance check
solutions be prepared at specified concentrations in order to meet
particular program needs.
7.12 Quality Control Sample (QCS)--Analysis of a QCS is required for
initial and periodic verification of calibration standards or stock
standard solutions in order to verify instrument performance. The QCS
must be obtained from an outside source different from the standard
stock solutions and prepared in the same acid mixture as the calibration
standards. The concentration of the analytes in the QCS solution should
be 1 mg/L, except silver, which must be limited to a concentration of
0.5 mg/L for solution stability. The QCS solution should be stored in a
FEP bottle and analyzed as needed to meet data-quality needs. A fresh
solution should be prepared quarterly or more frequently as needed.
7.13 Spectral Interference Check (SIC) Solutions--When interelement
corrections are applied, SIC solutions are needed containing
concentrations of the interfering elements at levels that will provide
an adequate test of the correction factors.
7.13.1 SIC solutions containing (a) 300 mg/L Fe; (b) 200 mg/L AL;
(c) 50 mg/L Ba; (d) 50 mg/L Be; (e) 50 mg/L Cd; (f) 50 mg/L Ce; (g) 50
mg/L Co; (h) 50 mg/L Cr; (i) 50 mg/L Cu; (j) 50
[[Page 398]]
mg/L Mn; (k) 50 mg/L Mo; (l) 50 mg/L Ni; (m) 50 mg/L Sn; (n) 50 mg/L
SiO2; (o) 50 mg/L Ti; (p) 50 mg/L Tl and (q) 50 mg/L V should
be prepared in the same acid mixture as the calibration standards and
stored in FEP bottles. These solutions can be used to periodically
verify a partial list of the on-line (and possible off-line)
interelement spectral correction factors for the recommended wavelengths
given in Table 1. Other solutions could achieve the same objective as
well. (Multielement SIC solutions\3\ may be prepared and substituted for
the single element solutions provided an analyte is not subject to
interference from more than one interferant in the solution.)
Note: If wavelengths other than those recommended in Table 1 are
used, other solutions different from those above (a through q) may be
required.
7.13.2 For interferences from iron and aluminum, only those
correction factors (positive or negative) when multiplied by 100 to
calculate apparent analyte concentrations that exceed the determined
analyte IDL or fall below the lower 3-sigma control limit of the
calibration blank need be tested on a daily basis.
7.13.3 For the other interfering elements, only those correction
factors (positive or negative) when multiplied by 10 to calculate
apparent analyte concentrations that exceed the determined analyte IDL
or fall below the lower 3-sigma control limit of the calibration blank
need be tested on a daily basis.
7.13.4 If the correction routine is operating properly, the
determined apparent analyte(s) concentration from analysis of each
interference solution (a through q) should fall within a specific
concentration range bracketing the calibration blank. This concentration
range is calculated by multiplying the concentration of the interfering
element by the value of the correction factor being tested and dividing
by 10. If after subtraction of the calibration blank the apparent
analyte concentration is outside (above or below) this range, a change
in the correction factor of more than 10% should be suspected. The cause
of the change should be determined and corrected and the correction
factor should be updated.
Note: The SIC solution should be analyzed more than once to confirm
a change has occurred with adequate rinse time between solutions and
before subsequent analysis of the calibration blank.
7.13.5 If the correction factors tested on a daily basis are found
to be within the 10% criteria for five consecutive days, the required
verification frequency of those factors in compliance may be extended to
a weekly basis. Also, if the nature of the samples analyzed is such
(e.g., finished drinking water) that they do not contain concentrations
of the interfering elements at the 10 mg/L level, daily verification is
not required; however, all interelement spectral correction factors must
be verified annually and updated, if necessary.
7.13.6 If the instrument does not display negative concentration
values, fortify the SIC solutions with the elements of interest at 1 mg/
L and test for analyte recoveries that are below 95%. In the absence of
measurable analyte, over-correction could go undetected because a
negative value could be reported as zero.
7.14 For instruments without interelement correction capability or
when interelement corrections are not used, SIC solutions (containing
similar concentrations of the major components in the samples, e.g., 10
mg/L) can serve to verify the absence of effects at the wavelengths
selected. These data must be kept on file with the sample analysis data.
If the SIC solution confirms an operative interference that is 10% of
the analyte concentration, the analyte must be determined using a
wavelength and background correction location free of the interference
or by another approved test procedure. Users are advised that high salt
concentrations can cause analyte signal suppressions and confuse
interference tests.
7.15 Plasma Solution--The plasma solution is used for determining
the optimum viewing height of the plasma above the work coil prior to
using the method (Section 10.2). The solution is prepared by adding a 5
mL aliquot from each of the stock standard solutions of arsenic, lead,
selenium, and thallium to a mixture of 20 mL (1 + 1) nitric acid and 20
mL (1 + 1) hydrochloric acid and diluting to 500 mL with reagent water.
Store in a FEP bottle.
8.0 Sample Collection, Preservation, and Storage
8.1 Prior to the collection of an aqueous sample, consideration
should be given to the type of data required, (i.e., dissolved or total
recoverable), so that appropriate preservation and pretreatment steps
can be taken. The pH of all aqueous samples must be tested immediately
prior to aliquoting for processing or ``direct analysis'' to ensure the
sample has been properly preserved. If properly acid preserved, the
sample can be held up to six months before analysis.
8.2 For the determination of the dissolved elements, the sample must
be filtered through a 0.45 [micro]m pore diameter membrane filter at the
time of collection or as soon thereafter as practically possible. (Glass
or plastic filtering apparatus are recommended to avoid possible
contamination. Only plastic apparatus should be used when the
determinations of boron and silica are critical.) Use a portion of the
filtered sample to rinse the filter flask, discard this portion and
collect the required volume of filtrate. Acidify
[[Page 399]]
the filtrate with (1 + 1) nitric acid immediately following filtration
to pH <2.
8.3 For the determination of total recoverable elements in aqueous
samples, samples are not filtered, but acidified with (1 + 1) nitric
acid to pH <2 (normally, 3 mL of (1 + 1) acid per liter of sample is
sufficient for most ambient and drinking water samples). Preservation
may be done at the time of collection, however, to avoid the hazards of
strong acids in the field, transport restrictions, and possible
contamination it is recommended that the samples be returned to the
laboratory within two weeks of collection and acid preserved upon
receipt in the laboratory. Following acidification, the sample should be
mixed, held for 16 hours, and then verified to be pH <2 just prior
withdrawing an aliquot for processing or ``direct analysis''. If for
some reason such as high alkalinity the sample pH is verified to be
2, more acid must be added and the sample held for 16 hours
until verified to be pH <2. See Section 8.1.
Note: When the nature of the sample is either unknown or is known to
be hazardous, acidification should be done in a fume hood. See Section
5.2.
8.4 Solid samples require no preservation prior to analysis other
than storage at 4 [deg]C. There is no established holding time
limitation for solid samples.
8.5 For aqueous samples, a field blank should be prepared and
analyzed as required by the data user. Use the same container and acid
as used in sample collection.
9.0 Quality Control
9.1 Each laboratory using this method is required to operate a
formal quality control (QC) program. The minimum requirements of this
program consist of an initial demonstration of laboratory capability,
and the periodic analysis of laboratory reagent blanks, fortified blanks
and other laboratory solutions as a continuing check on performance. The
laboratory is required to maintain performance records that define the
quality of the data thus generated.
9.2 Initial Demonstration of Performance (mandatory).
9.2.1 The initial demonstration of performance is used to
characterize instrument performance (determination of linear dynamic
ranges and analysis of quality control samples) and laboratory
performance (determination of method detection limits) prior to analyses
conducted by this method.
9.2.2 Linear dynamic range (LDR)--The upper limit of the LDR must be
established for each wavelength utilized. It must be determined from a
linear calibration prepared in the normal manner using the established
analytical operating procedure for the instrument. The LDR should be
determined by analyzing succeedingly higher standard concentrations of
the analyte until the observed analyte concentration is no more than 10%
below the stated concentration of the standard. Determined LDRs must be
documented and kept on file. The LDR which may be used for the analysis
of samples should be judged by the analyst from the resulting data.
Determined sample analyte concentrations that are greater than 90% of
the determined upper LDR limit must be diluted and reanalyzed. The LDRs
should be verified annually or whenever, in the judgment of the analyst,
a change in analytical performance caused by either a change in
instrument hardware or operating conditions would dictate they be
redetermined.
9.2.3 Quality control sample (QCS)--When beginning the use of this
method, on a quarterly basis, after the preparation of stock or
calibration standard solutions or as required to meet data-quality
needs, verify the calibration standards and acceptable instrument
performance with the preparation and analyses of a QCS (Section 7.12).
To verify the calibration standards the determined mean concentrations
from three analyses of the QCS must be within 5% of the stated values.
If the calibration standard cannot be verified, performance of the
determinative step of the method is unacceptable. The source of the
problem must be identified and corrected before either proceeding on
with the initial determination of method detection limits or continuing
with on-going analyses.
9.2.4 Method detection limit (MDL)--MDLs must be established for all
wavelengths utilized, using reagent water (blank) fortified at a
concentration of two to three times the estimated instrument detection
limit.\15\ To determine MDL values, take seven replicate aliquots of the
fortified reagent water and process through the entire analytical
method. Perform all calculations defined in the method and report the
concentration values in the appropriate units. Calculate the MDL as
follows:
MDL = (t) x (S)
where:
t = students' t value for a 99% confidence level and a standard
deviation estimate with n-1 degrees of freedom [t = 3.14 for
seven replicates]
S = standard deviation of the replicate analyses
Note: If additional confirmation is desired, reanalyze the seven
replicate aliquots on two more nonconsecutive days and again calculate
the MDL values for each day. An average of the three MDL values for each
analyte may provide for a more appropriate MDL estimate. If the relative
standard deviation (RSD) from the analyses of the seven aliquots is
<10%, the concentration used to determine the analyte MDL may have been
inappropriately high for the determination. If so, this could result in
the calculation of
[[Page 400]]
an unrealistically low MDL. Concurrently, determination of MDL in
reagent water represents a best case situation and does not reflect
possible matrix effects of real world samples. However, successful
analyses of LFMs (Section 9.4) and the analyte addition test described
in Section 9.5.1 can give confidence to the MDL value determined in
reagent water. Typical single laboratory MDL values using this method
are given in Table 4.
The MDLs must be sufficient to detect analytes at the required
levels according to compliance monitoring regulation (Section 1.2). MDLs
should be determined annually, when a new operator begins work or
whenever, in the judgment of the analyst, a change in analytical
performance caused by either a change in instrument hardware or
operating conditions would dictate they be redetermined.
9.3 Assessing Laboratory Performance (mandatory)
9.3.1 Laboratory reagent blank (LRB)--The laboratory must analyze at
least one LRB (Section 7.10.2) with each batch of 20 or fewer samples of
the same matrix. LRB data are used to assess contamination from the
laboratory environment. LRB values that exceed the MDL indicate
laboratory or reagent contamination should be suspected. When LRB values
constitute 10% or more of the analyte level determined for a sample or
is 2.2 times the analyte MDL whichever is greater, fresh aliquots of the
samples must be prepared and analyzed again for the affected analytes
after the source of contamination has been corrected and acceptable LRB
values have been obtained.
9.3.2 Laboratory fortified blank (LFB)--The laboratory must analyze
at least one LFB (Section 7.10.3) with each batch of samples. Calculate
accuracy as percent recovery using the following equation:
[GRAPHIC] [TIFF OMITTED] TR18MY12.002
where:
R = percent recovery
LFB = laboratory fortified blank
LRB = laboratory reagent blank
s = concentration equivalent of analyte added to fortify the LBR
solution
If the recovery of any analyte falls outside the required control
limits of 85-115%, that analyte is judged out of control, and the source
of the problem should be identified and resolved before continuing
analyses.
9.3.3 The laboratory must use LFB analyses data to assess laboratory
performance against the required control limits of 85-115% (Section
9.3.2). When sufficient internal performance data become available
(usually a minimum of 20-30 analyses), optional control limits can be
developed from the mean percent recovery (x) and the standard deviation
(S) of the mean percent recovery. These data can be used to establish
the upper and lower control limits as follows:
UPPER CONTROL LIMIT = x + 3S
LOWER CONTROL LIMIT = x - 3S
The optional control limits must be equal to or better than the
required control limits of 85-115%. After each five to 10 new recovery
measurements, new control limits can be calculated using only the most
recent 20-30 data points. Also, the standard deviation (S) data should
be used to establish an on-going precision statement for the level of
concentrations included in the LFB. These data must be kept on file and
be available for review.
9.3.4 Instrument performance check (IPC) solution--For all
determinations the laboratory must analyze the IPC solution (Section
7.11) and a calibration blank immediately following daily calibration,
after every 10th sample (or more frequently, if required) and at the end
of the sample run. Analysis of the calibration blank should always be
s = fortified sample concentration
C = sample background concentration
s = concentration equivalent of analyte added to fortify the sample
9.4.4 If the recovery of any analyte falls outside the designated
LFM recovery range, and the laboratory performance for that analyte is
shown to be in control (Section 9.3), the recovery problem encountered
with the fortified sample is judged to be matrix related, not system
related. The data user should be informed that the result for that
analyte in the unfortified sample is suspect due to either the
heterogeneous nature of the sample or matrix effects and analysis by
method of standard addition or the use of an internal standard(s)
(Section 11.5) should be considered.
9.4.5 Where reference materials are available, they should be
analyzed to provide additional performance data. The analysis of
reference samples is a valuable tool for demonstrating the ability to
perform the method acceptably. Reference materials containing high
concentrations of analytes can provide additional information on the
performance of the spectral interference correction routine.
9.5 Assess the possible need for the method of standard additions
(MSA) or internal standard elements by the following tests. Directions
for using MSA or internal standard(s) are given in Section 11.5.
9.5.1 Analyte addition test: An analyte(s) standard added to a
portion of a prepared sample, or its dilution, should be recovered to
within 85% to 115% of the known value. The analyte(s) addition should
produce a
[[Page 402]]
minimum level of 20 times and a maximum of 100 times the method
detection limit. If the analyte addition is <20% of the sample analyte
concentration, the following dilution test should be used. If recovery
of the analyte(s) is not within the specified limits, a matrix effect
should be suspected, and the associated data flagged accordingly. The
method of additions or the use of an appropriate internal standard
element may provide more accurate data.
9.5.2 Dilution test: If the analyte concentration is sufficiently
high (minimally, a factor of 50 above the instrument detection limit in
the original solution but <90% of the linear limit), an analysis of a 1
+ 4 dilution should agree (after correction for the fivefold dilution)
within 10% of the original determination. If not, a chemical or physical
interference effect should be suspected and the associated data flagged
accordingly. The method of standard additions or the use of an internal-
standard element may provide more accurate data for samples failing this
test.
10.0 Calibration and Standardization
10.1 Specific wavelengths are listed in Table 1. Other wavelengths
may be substituted if they can provide the needed sensitivity and are
corrected for spectral interference. However, because of the difference
among various makes and models of spectrometers, specific instrument
operating conditions cannot be given. The instrument and operating
conditions utilized for determination must be capable of providing data
of acceptable quality to the program and data user. The analyst should
follow the instructions provided by the instrument manufacturer unless
other conditions provide similar or better performance for a task.
Operating conditions for aqueous solutions usually vary from 1100-1200
watts forward power, 15-16 mm viewing height, 15-19 L/min. argon coolant
flow, 0.6-1 L/min. argon aerosol flow, 1-1.8 mL/min. sample pumping rate
with a one minute preflush time and measurement time near 1 s per
wavelength peak (for sequential instruments) and near 10 s per sample
(for simultaneous instruments). Use of the Cu/Mn intensity ratio at
324.754 nm and 257.610 nm (by adjusting the argon aerosol flow) has been
recommended as a way to achieve repeatable interference correction
factors.\17\
10.2 Prior to using this method optimize the plasma operating
conditions. The following procedure is recommended for vertically
configured plasmas. The purpose of plasma optimization is to provide a
maximum signal-to-background ratio for the least sensitive element in
the analytical array. The use of a mass flow controller to regulate the
nebulizer gas flow rate greatly facilitates the procedure.
10.2.1 Ignite the plasma and select an appropriate incident rf power
with minimum reflected power. Allow the instrument to become thermally
stable before beginning. This usually requires at least 30 to 60 minutes
of operation. While aspirating the 1000 [micro]g/mL solution of yttrium
(Section 7.8.32), follow the instrument manufacturer's instructions and
adjust the aerosol carrier gas flow rate through the nebulizer so a
definitive blue emission region of the plasma extends approximately from
5-20 mm above the top of the work coil.\18\ Record the nebulizer gas
flow rate or pressure setting for future reference.
10.2.2 After establishing the nebulizer gas flow rate, determine the
solution uptake rate of the nebulizer in mL/min. by aspirating a known
volume calibration blank for a period of at least three minutes. Divide
the spent volume by the aspiration time (in minutes) and record the
uptake rate. Set the peristaltic pump to deliver the uptake rate in a
steady even flow.
10.2.3 After horizontally aligning the plasma and/or optically
profiling the spectrometer, use the selected instrument conditions from
Sections 10.2.1 and 10.2.2, and aspirate the plasma solution (Section
7.15), containing 10 [micro]g/mL each of As, Pb, Se and Tl. Collect
intensity data at the wavelength peak for each analyte at 1 mm intervals
from 14-18 mm above the top of the work coil. (This region of the plasma
is commonly referred to as the analytical zone.)\19\ Repeat the process
using the calibration blank. Determine the net signal to blank intensity
ratio for each analyte for each viewing height setting. Choose the
height for viewing the plasma that provides the largest intensity ratio
for the least sensitive element of the four analytes. If more than one
position provides the same ratio, select the position that provides the
highest net intensity counts for the least sensitive element or accept a
compromise position of the intensity ratios of all four analytes.
10.2.4 The instrument operating condition finally selected as being
optimum should provide the lowest reliable instrument detection limits
and method detection limits. Refer to Tables 1 and 4 for comparison of
IDLs and MDLs, respectively.
10.2.5 If either the instrument operating conditions, such as
incident power and/or nebulizer gas flow rate are changed, or a new
torch injector tube having a different orifice i.d. is installed, the
plasma and plasma viewing height should be reoptimized.
10.2.6 Before daily calibration and after the instrument warmup
period, the nebulizer gas flow must be reset to the determined optimized
flow. If a mass flow controller is being used, it should be reset to the
recorded optimized flow rate. In order to maintain valid spectral
interelement correction routines the nebulizer gas flow rate should be
[[Page 403]]
the same from day-to-day (<2% change). The change in signal intensity
with a change in nebulizer gas flow rate for both ``hard'' (Pb 220.353
nm) and ``soft'' (Cu 324.754) lines is illustrated in Figure 1.
10.3 Before using the procedure (Section 11.0) to analyze samples,
there must be data available documenting initial demonstration of
performance. The required data and procedure is described in Section
9.2. This data must be generated using the same instrument operating
conditions and calibration routine (Section 11.4) to be used for sample
analysis. These documented data must be kept on file and be available
for review by the data user.
10.4 After completing the initial demonstration of performance, but
before analyzing samples, the laboratory must establish and initially
verify an interelement spectral interference correction routine to be
used during sample analysis. A general description concerning spectral
interference and the analytical requirements for background correction
and for correction of interelement spectral interference in particular
are given in Section 4.1. To determine the appropriate location for
background correction and to establish the interelement interference
correction routine, repeated spectral scan about the analyte wavelength
and repeated analyses of the single element solutions may be required.
Criteria for determining an interelement spectral interference is an
apparent positive or negative concentration on the analyte that is
outside the 3-sigma control limits of the calibration blank for the
analyte. (The upper-control limit is the analyte IDL.) Once established,
the entire routine must be initially and periodically verified annually,
or whenever there is a change in instrument operating conditions
(Section 10.2.5). Only a portion of the correction routine must be
verified more frequently or on a daily basis. Test criteria and required
solutions are described in Section 7.13. Initial and periodic
verification data of the routine should be kept on file. Special cases
where on-going verification are required is described in Section 7.14.
11.0 Procedure
11.1 Aqueous Sample Preparation--Dissolved Analytes
11.1.1 For the determination of dissolved analytes in ground and
surface waters, pipet an aliquot (20 mL) of the filtered, acid preserved
sample into a 50 mL polypropylene centrifuge tube. Add an appropriate
volume of (1 + 1) nitric acid to adjust the acid concentration of the
aliquot to approximate a 1% (v/v) nitric acid solution (e.g., add 0.4 mL
(1 + 1) HNO3 to a 20 mL aliquot of sample). Cap the tube and
mix. The sample is now ready for analysis (Section 1.3). Allowance for
sample dilution should be made in the calculations. (If mercury is to be
determined, a separate aliquot must be additionally acidified to contain
1% (v/v) HCl to match the signal response of mercury in the calibration
standard and reduce memory interference effects. Section 1.9).
Note: If a precipitate is formed during acidification, transport, or
storage, the sample aliquot must be treated using the procedure
described in Sections 11.2.2 through 11.2.7 prior to analysis.
11.2 Aqueous Sample Preparation--Total Recoverable Analytes
11.2.1 For the ``direct analysis'' of total recoverable analytes in
drinking water samples containing turbidity <1 NTU, treat an unfiltered
acid preserved sample aliquot using the sample preparation procedure
described in Section 11.1.1 while making allowance for sample dilution
in the data calculation (Section 1.2). For the determination of total
recoverable analytes in all other aqueous samples or for
preconcentrating drinking water samples prior to analysis follow the
procedure given in Sections 11.2.2 through 11.2.7.
11.2.2 For the determination of total recoverable analytes in
aqueous samples (other than drinking water with <1 NTU turbidity),
transfer a 100 mL (1 mL) aliquot from a well mixed, acid preserved
sample to a 250 mL Griffin beaker (Sections 1.2, 1.3, 1.6, 1.7, 1.8, and
1.9). (When necessary, smaller sample aliquot volumes may be used.)
Note: If the sample contains undissolved solids 1%, a
well mixed, acid preserved aliquot containing no more than 1 g
particulate material should be cautiously evaporated to near 10 mL and
extracted using the acid-mixture procedure described in Sections 11.3.3
through 11.3.6.
11.2.3 Add 2 mL (1 + 1) nitric acid and 1.0 mL of (1 + 1)
hydrochloric acid to the beaker containing the measured volume of
sample. Place the beaker on the hot plate for solution evaporation. The
hot plate should be located in a fume hood and previously adjusted to
provide evaporation at a temperature of approximately but no higher than
85 [deg]C. (See the following note.) The beaker should be covered with
an elevated watch glass or other necessary steps should be taken to
prevent sample contamination from the fume hood environment.
Note: For proper heating adjust the temperature control of the hot
plate such that an uncovered Griffin beaker containing 50 mL of water
placed in the center of the hot plate can be maintained at a temperature
approximately but no higher than 85 [deg]C. (Once the beaker is covered
with a watch glass the temperature of the water will rise to
approximately 95 [deg]C.)
[[Page 404]]
11.2.4 Reduce the volume of the sample aliquot to about 20 mL by
gentle heating at 85 [deg]C. DO NOT BOIL. This step takes about two
hours for a 100 mL aliquot with the rate of evaporation rapidly
increasing as the sample volume approaches 20 mL. (A spare beaker
containing 20 mL of water can be used as a gauge.)
11.2.5 Cover the lip of the beaker with a watch glass to reduce
additional evaporation and gently reflux the sample for 30 minutes.
(Slight boiling may occur, but vigorous boiling must be avoided to
prevent loss of the HCl-H2O azeotrope.)
11.2.6 Allow the beaker to cool. Quantitatively transfer the sample
solution to a 50 mL volumetric flask, make to volume with reagent water,
stopper and mix.
11.2.7 Allow any undissolved material to settle overnight, or
centrifuge a portion of the prepared sample until clear. (If after
centrifuging or standing overnight the sample contains suspended solids
that would clog the nebulizer, a portion of the sample may be filtered
for their removal prior to analysis. However, care should be exercised
to avoid potential contamination from filtration.) The sample is now
ready for analysis. Because the effects of various matrices on the
stability of diluted samples cannot be characterized, all analyses
should be performed as soon as possible after the completed preparation.
11.3 Solid Sample Preparation--Total Recoverable Analytes
11.3.1 For the determination of total recoverable analytes in solid
samples, mix the sample thoroughly and transfer a portion (20
g) to tared weighing dish, weigh the sample and record the wet weight
(WW). (For samples with <35% moisture a 20 g portion is sufficient. For
samples with moisture 35% a larger aliquot 50-100 g is
required.) Dry the sample to a constant weight at 60 [deg]C and record
the dry weight (DW) for calculation of percent solids (Section 12.6).
(The sample is dried at 60 [deg]C to prevent the loss of mercury and
other possible volatile metallic compounds, to facilitate sieving, and
to ready the sample for grinding.)
11.3.2 To achieve homogeneity, sieve the dried sample using a 5-mesh
polypropylene sieve and grind in a mortar and pestle. (The sieve, mortar
and pestle should be cleaned between samples.) From the dried, ground
material weigh accurately a representative 1.0 0.01 g aliquot (W) of the sample and transfer to a 250
mL Phillips beaker for acid extraction (Sections 1.6, 1.7, 1.8, and
1.9).
11.3.3 To the beaker add 4 mL of (1 + 1) HNO3 and 10 mL
of (1 + 4) HCl. Cover the lip of the beaker with a watch glass. Place
the beaker on a hot plate for reflux extraction of the analytes. The hot
plate should be located in a fume hood and previously adjusted to
provide a reflux temperature of approximately 95 [deg]C. (See the
following note.)
Note: For proper heating adjust the temperature control of the hot
plate such that an uncovered Griffin beaker containing 50 mL of water
placed in the center of the hot plate can be maintained at a temperature
approximately but no higher than 85 [deg]C. (Once the beaker is covered
with a watch glass the temperature of the water will rise to
approximately 95 [deg]C.) Also, a block digester capable of maintaining
a temperature of 95 [deg]C and equipped with 250 mL constricted
volumetric digestion tubes may be substituted for the hot plate and
conical beakers in the extraction step.
11.3.4 Heat the sample and gently reflux for 30 minutes. Very slight
boiling may occur, however vigorous boiling must be avoided to prevent
loss of the HCl-H2O azeotrope. Some solution evaporation will
occur (3-4 mL).
11.3.5 Allow the sample to cool and quantitatively transfer the
extract to a 100 mL volumetric flask. Dilute to volume with reagent
water, stopper and mix.
11.3.6 Allow the sample extract solution to stand overnight to
separate insoluble material or centrifuge a portion of the sample
solution until clear. (If after centrifuging or standing overnight the
extract solution contains suspended solids that would clog the
nebulizer, a portion of the extract solution may be filtered for their
removal prior to analysis. However, care should be exercised to avoid
potential contamination from filtration.) The sample extract is now
ready for analysis. Because the effects of various matrices on the
stability of diluted samples cannot be characterized, all analyses
should be performed as soon as possible after the completed preparation.
11.4 Sample Analysis
11.4.1 Prior to daily calibration of the instrument inspect the
sample introduction system including the nebulizer, torch, injector tube
and uptake tubing for salt deposits, dirt and debris that would restrict
solution flow and affect instrument performance. Clean the system when
needed or on a daily basis.
11.4.2 Configure the instrument system to the selected power and
operating conditions as determined in Sections 10.1 and 10.2.
11.4.3 The instrument must be allowed to become thermally stable
before calibration and analyses. This usually requires at least 30 to 60
minutes of operation. After instrument warmup, complete any required
optical profiling or alignment particular to the instrument.
[[Page 405]]
11.4.4 For initial and daily operation calibrate the instrument
according to the instrument manufacturer's recommended procedures, using
mixed calibration standard solutions (Section 7.9) and the calibration
blank (Section 7.10.1). A peristaltic pump must be used to introduce all
solutions to the nebulizer. To allow equilibrium to be reached in the
plasma, aspirate all solutions for 30 seconds after reaching the plasma
before beginning integration of the background corrected signal to
accumulate data. When possible, use the average value of replicate
integration periods of the signal to be correlated to the analyte
concentration. Flush the system with the rinse blank (Section 7.10.4)
for a minimum of 60 seconds (Section 4.4) between each standard. The
calibration line should consist of a minimum of a calibration blank and
a high standard. Replicates of the blank and highest standard provide an
optimal distribution of calibration standards to minimize the confidence
band for a straight-line calibration in a response region with uniform
variance.\20\
11.4.5 After completion of the initial requirements of this method
(Sections 10.3 and 10.4), samples should be analyzed in the same
operational manner used in the calibration routine with the rinse blank
also being used between all sample solutions, LFBs, LFMs, and check
solutions (Section 7.10.4).
11.4.6 During the analysis of samples, the laboratory must comply
with the required quality control described in Sections 9.3 and 9.4.
Only for the determination of dissolved analytes or the ``direct
analysis'' of drinking water with turbidity of <1 NTU is the sample
digestion step of the LRB, LFB, and LFM not required.
11.4.7 Determined sample analyte concentrations that are 90% or more
of the upper limit of the analyte LDR must be diluted with reagent water
that has been acidified in the same manner as calibration blank and
reanalyzed (see Section 11.4.8). Also, for the interelement spectral
interference correction routines to remain valid during sample analysis,
the interferant concentration must not exceed its LDR. If the
interferant LDR is exceeded, sample dilution with acidified reagent
water and reanalysis is required. In these circumstances analyte
detection limits are raised and determination by another approved test
procedure that is either more sensitive and/or interference free is
recommended.
11.4.8 When it is necessary to assess an operative matrix
interference (e.g., signal reduction due to high dissolved solids), the
tests described in Section 9.5 are recommended.
11.4.9 Report data as directed in Section 12.0.
11.5 If the method of standard additions (MSA) is used, standards
are added at one or more levels to portions of a prepared sample. This
technique \21\ compensates for enhancement or depression of an analyte
signal by a matrix. It will not correct for additive interferences such
as contamination, interelement interferences, or baseline shifts. This
technique is valid in the linear range when the interference effect is
constant over the range, the added analyte responds the same as the
endogenous analyte, and the signal is corrected for additive
interferences. The simplest version of this technique is the single-
addition method. This procedure calls for two identical aliquots of the
sample solution to be taken. To the first aliquot, a small volume of
standard is added; while to the second aliquot, a volume of acid blank
is added equal to the standard addition. The sample concentration is
calculated by the following:
[GRAPHIC] [TIFF OMITTED] TR18MY12.004
where:
C = Concentration of the standard solution (mg/L)
S1 = Signal for fortified aliquot
S2 = Signal for unfortified aliquot
V1 = Volume of the standard addition (L)
V2 = Volume of the sample aliquot (L) used for MSA
For more than one fortified portion of the prepared sample, linear
regression analysis can be applied using a computer or calculator
program to obtain the concentration of the sample solution. An
alternative to using the method of standard additions is use of the
internal standard technique by adding one or more elements (not in the
samples and verified not to cause an uncorrected interelement spectral
interference) at the same concentration (which is sufficient for optimum
precision) to the prepared samples (blanks and standards) that are
affected the same as the analytes by the sample matrix. Use the ratio of
analyte signal to the internal standard signal for calibration and
quantitation.
12.0 Data Analysis and Calculations
12.1 Sample data should be reported in units of mg/L for aqueous
samples and mg/kg dry weight for solid samples.
[[Page 406]]
12.2 For dissolved aqueous analytes (Section 11.1) report the data
generated directly from the instrument with allowance for sample
dilution. Do not report analyte concentrations below the IDL.
12.3 For total recoverable aqueous analytes (Section 11.2), multiply
solution analyte concentrations by the dilution factor 0.5, when 100 mL
aliquot is used to produce the 50 mL final solution, and report data as
instructed in Section 12.4. If a different aliquot volume other than 100
mL is used for sample preparation, adjust the dilution factor
accordingly. Also, account for any additional dilution of the prepared
sample solution needed to complete the determination of analytes
exceeding 90% or more of the LDR upper limit. Do not report data below
the determined analyte MDL concentration or below an adjusted detection
limit reflecting smaller sample aliquots used in processing or
additional dilutions required to complete the analysis.
12.4 For analytes with MDLs <0.01 mg/L, round the data values to the
thousandth place and report analyte concentrations up to three
significant figures. For analytes with MDLs <0.01 mg/L round the data
values to the 100th place and report analyte concentrations up to three
significant figures. Extract concentrations for solids data should be
rounded in a similar manner before calculations in Section 12.5 are
performed.
12.5 For total recoverable analytes in solid samples (Section 11.3),
round the solution analyte concentrations (mg/L) as instructed in
Section 12.4. Report the data up to three significant figures as mg/kg
dry-weight basis unless specified otherwise by the program or data user.
Calculate the concentration using the equation below:
[GRAPHIC] [TIFF OMITTED] TR18MY12.005
where:
C = Concentration in extract (mg/L)
V = Volume of extract (L, 100 mL = 0.1L)
D = Dilution factor (undiluted = 1)
W = Weight of sample aliquot extracted (g x 0.001 = kg)
Do not report analyte data below the estimated solids MDL or an
adjusted MDL because of additional dilutions required to complete the
analysis.
12.6 To report percent solids in solid samples (Section 11.3)
calculate as follows:
[GRAPHIC] [TIFF OMITTED] TR18MY12.006
where:
DW = Sample weight (g) dried at 60 [ordm]C
WW = Sample weight (g) before drying
Note: If the data user, program or laboratory requires that the
reported percent solids be determined by drying at 105 [deg]C, repeat
the procedure given in Section 11.3 using a separate portion
(20 g) of the sample and dry to constant weight at 103-105
[deg]C.
12.7 The QC data obtained during the analyses provide an indication
of the quality of the sample data and should be provided with the sample
results.
13.0 Method Performance
13.1 Listed in Table 4 are typical single laboratory total
recoverable MDLs determined for the recommended wavelengths using
simultaneous ICP-AES and the operating conditions given in Table 5. The
MDLs were determined in reagent blank matrix (best case situation). PTFE
beakers were used to avoid boron and silica contamination from glassware
with the final dilution to 50 mL completed in polypropylene centrifuged
tubes. The listed MDLs for solids are estimates and were calculated from
the aqueous MDL determinations.
13.2 Data obtained from single laboratory method testing are
summarized in Table 6 for five types of water samples consisting of
drinking water, surface water, ground water, and two wastewater
effluents. The data presented cover all analytes except cerium and
titanium. Samples were prepared using the procedure described in Section
11.2. For each matrix, five replicate aliquots were prepared, analyzed
and the average of the five determinations used to define the sample
background concentration of each analyte. In addition, two pairs of
duplicates were fortified at different concentration levels. For each
method analyte, the sample background concentration, mean percent
recovery, standard
[[Page 407]]
deviation of the percent recovery, and relative percent difference
between the duplicate fortified samples are listed in Table 6. The
variance of the five replicate sample background determinations is
included in the calculated standard deviation of the percent recovery
when the analyte concentration in the sample was greater than the MDL.
The tap and well waters were processed in Teflon and quartz beakers and
diluted in polypropylene centrifuged tubes. The nonuse of borosilicate
glassware is reflected in the precision and recovery data for boron and
silica in those two sample types.
13.3 Data obtained from single laboratory method testing are
summarized in Table 7 for three solid samples consisting of EPA 884
Hazardous Soil, SRM 1645 River Sediment, and EPA 286 Electroplating
Sludge. Samples were prepared using the procedure described in Section
11.3. For each method analyte, the sample background concentration, mean
percent recovery of the fortified additions, the standard deviation of
the percent recovery, and relative percent difference between duplicate
additions were determined as described in Section 13.2. Data presented
are for all analytes except cerium, silica, and titanium. Limited
comparative data to other methods and SRM materials are presented in
Reference 23 of Section 16.0.
13.4 Performance data for aqueous solutions independent of sample
preparation from a multilaboratory study are provided in Table 8.\22\
13.5 Listed in Table 9 are regression equations for precision and
bias for 25 analytes abstracted from EPA Method Study 27, a
multilaboratory validation study of Method 200.7.\1\ These equations
were developed from data received from 12 laboratories using the total
recoverable sample preparation procedure on reagent water, drinking
water, surface water and three industrial effluents. For a complete
review and description of the study, see Reference 16 of Section 16.0.
14.0 Pollution Prevention
14.1 Pollution prevention encompasses any technique that reduces or
eliminates the quantity or toxicity of waste at the point of generation.
Numerous opportunities for pollution prevention exist in laboratory
operation. The EPA has established a preferred hierarchy of
environmental management techniques that places pollution prevention as
the management option of first choice. Whenever feasible, laboratory
personnel should use pollution prevention techniques to address their
waste generation (e.g., Section 7.8). When wastes cannot be feasibly
reduced at the source, the Agency recommends recycling as the next best
option.
14.2 For information about pollution prevention that may be
applicable to laboratories and research institutions, consult ``Less is
Better: Laboratory Chemical Management for Waste Reduction'', available
from the American Chemical Society's Department of Government Relations
and Science Policy, 1155 16th Street NW., Washington, DC 20036, (202)
872-4477.
15.0 Waste Management
15.1 The Environmental Protection Agency requires that laboratory
waste management practices be conducted consistent with all applicable
rules and regulations. The Agency urges laboratories to protect the air,
water, and land by minimizing and controlling all releases from hoods
and bench operations, complying with the letter and spirit of any sewer
discharge permits and regulations, and by complying with all solid and
hazardous waste regulations, particularly the hazardous waste
identification rules and land disposal restrictions. For further
information on waste management consult ``The Waste Management Manual
for Laboratory Personnel'', available from the American Chemical Society
at the address listed in the Section 14.2.
16.0 References
1. U.S. Environmental Protection Agency. Inductively Coupled Plasma--
Atomic Emission Spectrometric Method for Trace Element
Analysis of Water and Wastes--Method 200.7, Dec. 1982. EPA-
600/4-79-020, revised March 1983.
2. U.S. Environmental Protection Agency. Inductively Coupled Plasma
Atomic Emission Spectroscopy Method 6010, SW-846 Test Methods
for Evaluating Solid Waste, 3rd Edition, 1986.
3. U.S. Environmental Protection Agency. Method 200.7: Determination of
Metals and Trace Elements in Water and Wastes by Inductively
Coupled Plasma--Atomic Emission Spectrometry, revision 3.3,
EPA 600 4-91/010, June 1991.
4. U.S. Environmental Protection Agency. Inductively Coupled Plasma--
Atomic Emission Spectrometry Method for the Analysis of Waters
and Solids, EMMC, July 1992.
5. Fassel, V.A. et al. Simultaneous Determination of Wear Metals in
Lubricating Oils by Inductively-Coupled Plasma Atomic Emission
Spectrometry. Anal. Chem. 48:516-519, 1976.
6. Merryfield, R.N. and R.C. Loyd. Simultaneous Determination of Metals
in Oil by Inductively Coupled Plasma Emission Spectrometry.
Anal. Chem. 51:1965-1968, 1979.
7. Winge, R.K. et al. Inductively Coupled Plasma--Atomic Emission
Spectroscopy: An Atlas of Spectral Information, Physical
Science Data 20. Elsevier Science Publishing, New York, New
York, 1985.
8. Boumans, P.W.J.M. Line Coincidence Tables for Inductively Coupled
Plasma
[[Page 408]]
Atomic Emission Spectrometry, 2nd edition. Pergamon Press,
Oxford, United Kingdom, 1984.
9. Carcinogens--Working With Carcinogens, Department of Health,
Education, and Welfare, Public Health Service, Center for
Disease Control, National Institute for Occupational Safety
and Health, Publication No. 77-206, Aug. 1977. Available from
the National Technical Information Service (NTIS) as PB-
277256.
10. OSHA Safety and Health Standards, General Industry, (29 CFR 1910),
Occupational Safety and Health Administration, OSHA 2206,
(Revised, January 1976).
11. Safety in Academic Chemistry Laboratories, American Chemical Society
Publication, Committee on Chemical Safety, 3rd Edition, 1979.
12. Proposed OSHA Safety and Health Standards, Laboratories,
Occupational Safety and Health Administration, Federal
Register, July 24, 1986.
13. Rohrbough, W.G. et al. Reagent Chemicals, American Chemical Society
Specifications, 7th edition. American Chemical Society,
Washington, DC, 1986.
14. American Society for Testing and Materials. Standard Specification
for Reagent Water, D1193-77. Annual Book of ASTM Standards,
Vol. 11.01. Philadelphia, PA, 1991.
15. Code of Federal Regulations 40, Ch. 1, Pt. 136 Appendix B.
16. Maxfield, R. and B. Mindak. EPA Method Study 27, Method 200.7 Trace
Metals by ICP, Nov. 1983. Available from National Technical
Information Service (NTIS) as PB 85-248-656.
17. Botto, R.I. Quality Assurance in Operating a Multielement ICP
Emission Spectrometer. Spectrochim. Acta, 39B(1):95-113, 1984.
18. Wallace, G.F., Some Factors Affecting the Performance of an ICP
Sample Introduction System. Atomic Spectroscopy, Vol. 4, p.
188-192, 1983.
19. Koirtyohann, S.R. et al. Nomenclature System for the Low-Power Argon
Inductively Coupled Plasma, Anal. Chem. 52:1965, 1980.
20. Deming, S.N. and S.L. Morgan. Experimental Design for Quality and
Productivity in Research, Development, and Manufacturing, Part
III, pp. 119-123. Short course publication by Statistical
Designs, 9941 Rowlett, Suite 6, Houston, TX 77075, 1989.
21. Winefordner, J.D., Trace Analysis: Spectroscopic Methods for
Elements, Chemical Analysis, Vol. 46, pp. 41-42.
22. Jones, C.L. et al. An Interlaboratory Study of Inductively Coupled
Plasma Atomic Emission Spectroscopy Method 6010 and Digestion
Method 3050. EPA-600/4-87-032, U.S. Environmental Protection
Agency, Las Vegas, Nevada, 1987.
23. Martin, T.D., E.R. Martin and SE. Long. Method 200.2: Sample
Preparation Procedure for Spectrochemical Analyses of Total
Recoverable Elements, EMSL ORD, USEPA, 1989.
17.0 Tables, Diagrams, Flowcharts, and Validation Data
Table 1--Wavelengths, Estimated Instrument Detection Limits, and Recommended Calibration
----------------------------------------------------------------------------------------------------------------
Estimated
Wavelength\a\ detection Calibrate\c\ to
Analyte (nm) limit\b\ (mg/L)
([micro]g/L)
----------------------------------------------------------------------------------------------------------------
Aluminum.................................................. 308.215 45 10
Antimony.................................................. 206.833 32 5
Arsenic................................................... 193.759 53 10
Barium.................................................... 493.409 2.3 1
Beryllium................................................. 313.042 0.27 1
Boron..................................................... 249.678 5.7 1
Cadmium................................................... 226.502 3.4 2
Calcium................................................... 315.887 30 10
Cerium.................................................... 413.765 48 2
Chromium.................................................. 205.552 6.1 5
Cobalt.................................................... 228.616 7.0 2
Copper.................................................... 324.754 5.4 2
Iron...................................................... 259.940 6.2 10
Lead...................................................... 220.353 42 10
Lithium................................................... 670.784 \d\ 3.7 5
Magnesium................................................. 279.079 30 10
Manganese................................................. 257.610 1.4 2
Mercury................................................... 194.227 2.5 2
Molybdenum................................................ 203.844 12 10
Nickel.................................................... 231.604 15 2
Phosphorus................................................ 214.914 76 10
Potassium................................................. 766.491 \e\ 700 20
Selenium.................................................. 196.090 75 5
Silica (SiO2)............................................. 251.611 \d\ 26 (SiO2) 10
Silver.................................................... 328.068 7.0 0.5
[[Page 409]]
Sodium.................................................... 588.995 29 10
Strontium................................................. 421.552 0.77 1
Thallium.................................................. 190.864 40 5
Tin....................................................... 189.980 25 4
Titanium.................................................. 334.941 3.8 10
Vanadium.................................................. 292.402 7.5 2
Zinc...................................................... 213.856 1.8 5
----------------------------------------------------------------------------------------------------------------
\a\ The wavelengths listed are recommended because of their sensitivity and overall acceptability. Other
wavelengths may be substituted if they can provide the needed sensitivity and are treated with the same
corrective techniques for spectral interference (see Section 4.1).
\b\ These estimated 3-sigma instrumental detection limits \16\ are provided only as a guide to instrumental
limits. The method detection limits are sample dependent and may vary as the sample matrix varies. Detection
limits for solids can be estimated by dividing these values by the grams extracted per liter, which depends
upon the extraction procedure. Divide solution detection limits by 10 for 1 g extracted to 100 mL for solid
detection limits.
\c\ Suggested concentration for instrument calibration.\2\ Other calibration limits in the linear ranges may be
used.
\d\ Calculated from 2-sigma data.\5\
\e\ Highly dependent on operating conditions and plasma position.
TABLE 2--On-Line Method Interelement Spectral Interferances Arising From
Interferants at the 100 mg/L Level
------------------------------------------------------------------------
Wavelength
Analyte (nm) Interferant*
------------------------------------------------------------------------
Ag.......................... 328.068 Ce, Ti, Mn
Al.......................... 308.215 V, Mo, Ce, Mn
As.......................... 193.759 V, Al, Co, Fe, Ni
B........................... 249.678 None
Ba.......................... 493.409 None
Be.......................... 313.042 V, Ce
Ca.......................... 315.887 Co, Mo, Ce
Cd.......................... 226.502 Ni, Ti, Fe, Ce
Ce.......................... 413.765 None
Co.......................... 228.616 Ti, Ba, Cd, Ni, Cr, Mo, Ce
Cr.......................... 205.552 Be, Mo, Ni
Cu.......................... 324.754 Mo, Ti
Fe.......................... 259.940 None
Hg.......................... 194.227 V, Mo
K........................... 766.491 None
Li.......................... 670.784 None
Mg.......................... 279.079 Ce
Mn.......................... 257.610 Ce
Mo.......................... 203.844 Ce
Na.......................... 588.995 None
Ni.......................... 231.604 Co, Tl
P........................... 214.914 Cu, Mo
Pb.......................... 220.353 Co, Al, Ce, Cu, Ni, Ti, Fe
Sb.......................... 206.833 Cr, Mo, Sn, Ti, Ce, Fe
Se.......................... 196.099 Fe
SiO2........................ 251.611 None
Sn.......................... 189.980 Mo, Ti, Fe, Mn, Si
Sr.......................... 421.552 None
Tl.......................... 190.864 Ti, Mo, Co, Ce, Al, V, Mn
Ti.......................... 334.941 None
V........................... 292.402 Mo, Ti, Cr, Fe, Ce
Zn.......................... 213.856 Ni, Cu, Fe
------------------------------------------------------------------------
* These on-line interferences from method analytes and titanium only
were observed using an instrument with 0.035 nm resolution (see
Section 4.1.2). Interferant ranked by magnitude of intensity with the
most severe interferant listed first in the row.
TABLE 3--Mixed Standard Solutions
----------------------------------------------------------------------------------------------------------------
Solution Analytes
----------------------------------------------------------------------------------------------------------------
I............................................ Ag, As, B, Ba, Ca, Cd, Cu, Mn, Sb, and Se
II........................................... K, Li, Mo, Na, Sr, and Ti
III.......................................... Co, P, V, and Ce
IV........................................... Al, Cr, Hg, SiO2, Sn, and Zn
V............................................ Be, Fe, Mg, Ni, Pb, and Tl
----------------------------------------------------------------------------------------------------------------
TABLE 4--Total Recoverable Method Detection Limits (MDL)
------------------------------------------------------------------------
MDLs Aqueous, mg/
Analyte L\(1)\ Solids, mg/kg\(2)\
------------------------------------------------------------------------
Ag.............................. 0.002 0.3
Al.............................. 0.02 3
As.............................. 0.008 2
B............................... 0.003 --
Ba.............................. 0.001 0.2
Be.............................. 0.0003 0.1
Ca.............................. 0.01 2
Cd.............................. 0.001 0.2
Ce.............................. 0.02 3
Co.............................. 0.002 0.4
Cr.............................. 0.004 0.8
Cu.............................. 0.003 0.5
Fe.............................. *0.03 6
Hg.............................. 0.007 2
K............................... 0.3 60
Li.............................. 0.001 0.2
Mg.............................. 0.02 3
Mn.............................. 0.001 0.2
Mo.............................. 0.004 1
Na.............................. 0.03 6
Ni.............................. 0.005 1
P............................... 0.06 12
Pb.............................. 0.01 2
Sb.............................. 0.008 2
Se.............................. 0.02 5
SiO2............................ 0.02 --
Sn.............................. 0.007 2
Sr.............................. 0.0003 0.1
Tl.............................. 0.001 0.2
Ti.............................. 0.02 3
V............................... 0.003 1
[[Page 410]]
Zn.............................. 0.002 0.3
------------------------------------------------------------------------
\(1)\ MDL concentrations are computed for original matrix with allowance
for 2x sample preconcentration during preparation. Samples were
processed in PTFE and diluted in 50-mL plastic centrifuge tubes.
\(2)\ Estimated, calculated from aqueous MDL determinations.
-- Boron not reported because of glassware contamination. Silica not
determined in solid samples.
* Elevated value due to fume-hood contamination.
TABLE 5--Inductively Coupled Plasma Instrument Operating Conditions
------------------------------------------------------------------------
------------------------------------------------------------------------
Incident rf power........................ 1100 watts
Reflected rf power....................... <5 watts
Viewing height above work coil........... 15 mm
Injector tube orifice i.d................ 1 mm
Argon supply............................. liquid argon
Argon pressure........................... 40 psi
Coolant argon flow rate.................. 19 L/min.
Aerosol carrier argon flow rate.......... 620 mL/min.
Auxiliary (plasma) argon flow rate....... 300 mL/min.
Sample uptake rate controlled to......... 1.2 mL/min.
------------------------------------------------------------------------
[[Page 411]]
Table 6--Precision and Recovery Data in Aqueous Matrices
--------------------------------------------------------------------------------------------------------------------------------------------------------
Average Average
Analyte Sample Low spike recovery R S (R) RPD High spike recovery R S (R) RPD
conc. mg/L mg/L (%) mg/L (%)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Tap Water
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ag................................. <0.002 0.05 95 0.7 2.1 0.2 96 0.0 0.0
Al................................. 0.185 0.05 98 8.8 1.7 0.2 105 3.0 3.1
As................................. <0.008 0.05 108 1.4 3.7 0.2 101 0.7 2.0
B.................................. 0.023 0.1 98 0.2 0.0 0.4 98 0.2 0.5
Ba................................. 0.042 0.05 102 1.6 2.2 0.2 98 0.4 0.8
Be................................. <0.0003 0.01 100 0.0 0.0 0.1 99 0.0 0.0
Ca................................. 35.2 5.0 101 8.8 1.7 20.0 103 2.0 0.9
Cd................................. <0.001 0.01 105 3.5 9.5 0.1 98 0.0 0.0
Co................................. <0.002 0.02 100 0.0 0.0 0.2 99 0.5 1.5
Cr................................. <0.004 0.01 110 0.0 0.0 0.1 102 0.0 0.0
Cu................................. <0.003 0.02 103 1.8 4.9 0.2 101 1.2 3.5
Fe................................. 0.008 0.1 106 1.0 1.8 0.4 105 0.3 0.5
Hg................................. <0.007 0.05 103 0.7 1.9 0.2 100 0.4 1.0
K.................................. 1.98 5.0 109 1.4 2.3 20. 107 0.7 1.7
Li................................. 0.006 0.02 103 6.9 3.8 0.2 110 1.9 4.4
Mg................................. 8.08 5.0 104 2.2 1.5 20.0 100 0.7 1.1
Mn................................. <0.001 0.01 100 0.0 0.0 0.1 99 0.0 0.0
Mo................................. <0.004 0.02 95 3.5 10.5 0.2 108 0.5 1.4
Na................................. 10.3 5.0 99 3.0 2.0 20.0 106 1.0 1.6
Ni................................. <0.005 0.02 108 1.8 4.7 0.2 104 1.1 2.9
P.................................. 0.045 0.1 102 13.1 9.4 0.4 104 3.2 1.3
Pb................................. <0.01 0.05 95 0.7 2.1 0.2 100 0.2 0.5
Sb................................. <0.008 0.05 99 0.7 2.0 0.2 102 0.7 2.0
Se................................. <0.02 0.1 87 1.1 3.5 0.4 99 0.8 2.3
SiO2............................... 6.5 5.0 104 3.3 3.4 20.0 96 1.1 2.3
Sn................................. <0.007 0.05 103 2.1 5.8 0.2 101 1.8 5.0
Sr................................. 0.181 0.1 102 3.3 2.1 0.4 105 0.8 1.0
Tl................................. <0.02 0.1 101 3.9 10.9 0.4 101 0.1 0.3
V.................................. <0.003 0.05 101 0.7 2.0 0.2 99 0.2 0.5
Zn................................. 0.005 0.05 101 3.7 9.0 0.2 98 0.9 2.5
--------------------------------------------------------------------------------------------------------------------------------------------------------
Pond Water
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ag................................. <0.002 0.05 92 0.0 0.0 0.2 94 0.0 0.0
Al................................. 0.819 0.2 88 10.0 5.0 0.8 100 2.9 3.7
As................................. <0.008 0.05 102 0.0 0.0 0.2 98 1.4 4.1
B.................................. 0.034 0.1 111 8.9 6.9 0.4 103 2.0 0.0
Ba................................. 0.029 0.05 96 0.9 0.0 0.2 97 0.3 0.5
Be................................. <0.0003 0.01 95 0.4 1.1 0.2 95 0.0 0.0
Ca................................. 53.9 5.0 * * 0.7 20.0 100 2.0 1.5
Cd................................. <0.001 0.01 107 0.0 0.0 0.1 97 0.0 0.0
Co................................. <0.002 0.02 100 2.7 7.5 0.2 97 0.7 2.1
Cr................................. <0.004 0.01 105 3.5 9.5 0.1 103 1.1 2.9
[[Page 412]]
Cu................................. <0.003 0.02 98 2.1 4.4 0.2 100 0.5 1.5
Fe................................. 0.875 0.2 95 8.9 2.8 0.8 97 3.2 3.6
Hg................................. <0.007 0.05 97 3.5 10.3 0.2 98 0.0 0.0
K.................................. 2.48 5.0 106 0.3 0.1 20.0 103 0.2 0.4
Li................................. <0.001 0.02 110 0.0 0.0 0.2 106 0.2 0.5
Mg................................. 10.8 5.0 102 0.5 0.0 20.0 96 0.7 1.3
Mn................................. 0.632 0.01 * * 0.2 0.1 97 2.3 0.3
Mo................................. <0.004 0.02 105 3.5 9.5 0.2 103 0.4 1.0
Na................................. 17.8 5.0 103 1.3 0.4 20.0 94 0.3 0.0
Ni................................. <0.005 0.02 96 5.6 9.1 0.2 100 0.7 1.5
P.................................. 0.196 0.1 91 14.7 0.3 0.4 108 3.9 1.3
Pb................................. <0.01 0.05 96 2.6 7.8 0.2 100 0.7 2.0
Sb................................. <0.008 0.05 102 2.8 7.8 0.2 104 0.4 1.0
Se................................. <0.02 0.1 104 2.1 5.8 0.4 103 1.6 4.4
SiO2............................... 7.83 5.0 151 1.6 1.3 20.0 117 0.4 0.6
Sn................................. <0.007 0.05 98 0.0 0.0 0.2 99 1.1 3.0
Sr................................. 0.129 0.1 105 0.4 0.0 0.4 99 0.1 0.2
Tl................................. <0.02 0.1 103 1.1 2.9 0.4 97 1.3 3.9
V.................................. 0.003 0.05 94 0.4 0.0 0.2 98 0.1 0.0
Zn................................. 0.006 0.05 97 1.6 1.8 0.2 94 0.4 0.0
--------------------------------------------------------------------------------------------------------------------------------------------------------
Well Water
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ag................................. <0.002 0.05 97 0.7 2.1 0.2 96 0.2 0.5
Al................................. 0.036 0.05 107 7.6 10.1 0.2 101 1.1 0.8
As................................. <0.008 0.05 107 0.7 1.9 0.2 104 0.4 1.0
B.................................. 0.063 0.1 97 0.6 0.7 0.4 98 0.8 2.1
Ba................................. 0.102 0.05 102 3.0 0.0 0.2 99 0.9 1.0
Be................................. <0.0003 0.01 100 0.0 0.0 0.1 100 0.0 0.0
Ca................................. 93.8 5.0 * * 2.1 20.0 100 4.1 0.1
Cd................................. 0.002 0.01 90 0.0 0.0 0.1 96 0.0 0.0
Co................................. <0.002 0.02 94 0.4 1.1 0.2 94 0.4 1.1
Cr................................. <0.004 0.01 100 7.1 20.0 0.1 100 0.4 1.0
Cu................................. <0.005 0.02 100 1.1 0.4 0.2 96 0.5 1.5
Fe................................. 0.042 0.1 99 2.3 1.4 0.4 97 1.4 3.3
Hg................................. <0.007 0.05 94 2.8 8.5 0.2 93 1.2 3.8
K.................................. 6.21 5.0 96 3.4 3.6 20.0 101 1.2 2.3
Li................................. 0.001 0.02 100 7.6 9.5 0.2 104 1.0 1.9
Mg................................. 24.5 5.0 95 5.6 0.3 20.0 93 1.6 1.2
Mn................................. 2.76 0.01 * * 0.4 0.1 * * 0.7
Mo................................. <0.004 0.02 108 1.8 4.7 0.2 101 0.2 0.5
Na................................. 35.0 5.0 101 11.4 0.8 20.0 100 3.1 1.5
Ni................................. <0.005 0.02 112 1.8 4.4 0.2 96 0.2 0.5
P.................................. 0.197 0.1 95 12.7 1.9 0.4 98 3.4 0.9
[[Page 413]]
Pb................................. <0.01 0.05 87 4.9 16.1 0.2 95 0.2 0.5
Sb................................. <0.008 0.05 98 2.8 8.2 0.2 99 1.4 4.0
Se................................. <0.02 0.1 102 0.4 1.0 0.4 94 1.1 3.4
SiO2............................... 13.1 5.0 93 4.8 2.8 20.0 99 0.8 0.0
Sn................................. <0.007 0.05 98 2.8 8.2 0.2 94 0.2 0.5
Sr................................. 0.274 0.1 94 5.7 2.7 0.4 95 1.7 2.2
Tl................................. <0.02 0.1 92 0.4 1.1 0.4 95 1.1 3.2
V.................................. <0.003 0.05 98 0.0 0.0 0.2 99 0.4 1.0
Zn................................. 0.538 0.05 * * 0.7 0.2 99 2.5 1.1
--------------------------------------------------------------------------------------------------------------------------------------------------------
Sewage Treatment Effluent
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ag................................. 0.009 0.05 92 1.5 3.6 0.2 95 0.1 0.0
Al................................. 1.19 0.05 * * 0.9 0.2 113 12.4 2.1
As................................. <0.008 0.05 99 2.1 6.1 0.2 93 2.1 6.5
B.................................. 0.226 0.1 217 16.3 9.5 0.4 119 13.1 20.9
Ba................................. 0.189 0.05 90 6.8 1.7 0.2 99 1.6 0.5
Be................................. <0.0003 0.01 94 0.4 1.1 0.1 100 0.4 1.0
Ca................................. 87.9 5.0 * * 0.6 20.0 101 3.7 0.0
Cd................................. 0.009 0.01 89 2.6 2.3 0.1 97 0.4 1.0
Co................................. 0.016 0.02 95 3.1 0.0 0.2 93 0.4 0.5
Cr................................. 0.128 0.01 * * 1.5 0.1 97 2.4 2.7
Cu................................. 0.174 0.02 98 33.1 4.7 0.2 98 3.0 1.4
Fe................................. 1.28 0.1 * * 2.8 0.4 111 7.0 0.6
Hg................................. <0.007 0.05 102 1.4 3.9 0.2 98 0.5 1.5
K.................................. 10.6 5.0 104 2.8 1.3 20.0 101 0.6 0.0
Li................................. 0.011 0.02 103 8.5 3.2 0.2 105 0.8 0.5
Mg................................. 22.7 5.0 100 4.4 0.0 20.0 92 1.1 0.2
Mn................................. 0.199 0.01 * * 2.0 0.1 104 1.9 0.3
Mo................................. 0.125 0.02 110 21.2 6.8 0.2 102 1.3 0.9
Na................................. 0.236 5.0 * * 0.0 20.0 * * 0.4
Ni................................. 0.087 0.02 122 10.7 4.5 0.2 98 0.8 1.1
P.................................. 4.71 0.1 * * 2.6 0.4 * * 1.4
Pb................................. 0.015 0.05 91 3.5 5.0 0.2 96 1.3 2.9
Sb................................. <0.008 0.05 97 0.7 2.1 0.2 103 1.1 2.9
Se................................. <0.02 0.1 108 3.9 10.0 0.4 101 2.6 7.2
SiO2............................... 16.7 5.0 124 4.0 0.9 20.0 108 1.1 0.8
Sn................................. 0.016 0.05 90 3.8 0.0 0.2 95 1.0 0.0
Sr................................. 0.515 0.1 103 6.4 0.5 0.4 96 1.6 0.2
Tl................................. <0.02 0.1 105 0.4 1.0 0.4 95 0.0 0.0
V.................................. 0.003 0.05 93 0.9 2.0 0.2 97 0.2 0.5
Zn................................. 0.160 0.05 98 3.3 1.9 0.2 101 1.0 1.4
--------------------------------------------------------------------------------------------------------------------------------------------------------
Industrial Effluent
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ag................................. <0.0003 0.05 88 0.0 0.0 0.2 84 0.9 3.0
Al................................. 0.054 0.05 88 11.7 12.2 0.2 90 3.9 8.1
As................................. <0.02 0.05 82 2.8 9.8 0.2 88 0.5 1.7
B.................................. 0.17 0.1 162 17.6 13.9 0.4 92 4.7 9.3
Ba................................. 0.083 0.05 86 8.2 1.6 0.2 85 2.3 2.4
Be................................. <0.0006 0.01 94 0.4 1.1 0.1 82 1.4 4.9
[[Page 414]]
Ca................................. 500 5.0 * * 2.8 20.0 * * 2.3
Cd................................. 0.008 0.01 85 4.7 6.1 0.1 82 1.4 4.4
Co................................. <0.004 0.02 93 1.8 5.4 0.2 83 0.4 1.2
Cr................................. 0.165 0.01 * * 4.5 0.1 106 6.6 5.6
Cu................................. 0.095 0.02 93 23.3 0.9 0.2 95 2.7 2.8
Fe................................. 0.315 0.1 88 16.4 1.0 0.4 99 6.5 8.0
Hg................................. <0.01 0.05 87 0.7 2.3 0.2 86 0.4 1.2
K.................................. 2.87 5.0 101 3.4 2.4 20.0 100 0.8 0.4
Li................................. 0.069 0.02 103 24.7 5.6 0.2 104 2.5 2.2
Mg................................. 6.84 5.0 87 3.1 0.0 20.0 87 0.9 1.2
Mn................................. 0.141 0.01 * * 1.2 0.1 89 6.6 4.8
Mo................................. 1.27 0.02 * * 0.0 0.2 100 15.0 2.7
Na................................. 1500 5.0 * * 2.7 20.0 * * 2.0
Ni................................. 0.014 0.02 98 4.4 3.0 0.2 87 0.5 1.1
P.................................. 0.326 0.1 105 16.0 4.7 0.4 97 3.9 1.4
Pb................................. 0.251 0.05 80 19.9 1.4 0.2 88 5.0 0.9
Sb................................. 2.81 0.05 * * 0.4 0.2 * * 2.0
Se................................. 0.021 0.1 106 2.6 3.2 0.4 105 1.9 4.6
SiO2............................... 6.83 5.0 99 6.8 1.7 20.0 100 2.2 3.0
Sn................................. <0.01 0.05 87 0.7 2.3 0.2 86 0.4 1.2
Sr................................. 6.54 0.1 * * 2.0 0.4 * * 2.7
Tl................................. <0.03 0.1 87 1.8 5.8 0.4 84 1.1 3.6
V.................................. <0.005 0.05 90 1.4 4.4 0.2 84 1.1 3.6
Zn................................. 0.024 0.05 89 6.0 4.4 0.2 91 3.5 8.9
--------------------------------------------------------------------------------------------------------------------------------------------------------
S (R) Standard deviation of percent recovery.
RPD Relative percent difference between duplicate spike determinations.
Sec. Appendix D to Part 136--Precision and Recovery Statements for
Methods for Measuring Metals
Two selected methods from ``Methods for Chemical Analysis of Water
and Wastes,'' EPA-600/4-79-020 (1979) have been subjected to
interlaboratory method validation studies. The two selected methods are
for Thallium and Zinc. The following precision and recovery statements
are presented in this appendix and incorporated into Part 136:
Method 279.2
For Thallium, Method 279.2 (Atomic Absorption, Furnace Technique)
replace the Precision and Accuracy Section statement with the following:
Precision and Accuracy
An interlaboratory study on metal analyses by this method was
conducted by the Quality Assurance Branch (QAB) of the Environmental
Monitoring Systems Laboratory--Cincinnati (EMSL-CI). Synthetic
concentrates containing various levels of this element were added to
reagent water, surface water, drinking water and three effluents. These
samples were digested by the total digestion procedure, 4.1.3 in this
manual. Results for the reagent water are given below. Results for other
water types and study details are found in ``EPA Method Study 31, Trace
Metals by Atomic Absorption (Furnace Techniques),'' National Technical
Information Service, 5285 Port Royal Road, Springfield, VA 22161 Order
No. PB 86-121 704/AS, by Copeland, F.R. and Maney, J.P., January 1986.
For a concentration range of 10.00-252 [micro]g/L
X = 0.8781(C) - 0.715
S = 0.1112(X) + 0.669
SR = 0.1005(X) + 0.241
Where:
C = True Value for the Concentration, [micro]g/L
X = Mean Recovery, [micro]g/L
S = Multi-laboratory Standard Deviation, [micro]g/L
SR = Single-analyst Standard Deviation, [micro]g/L
Method 289.2
For Zinc, Method 289.2 (Atomic Absorption, Furnace Technique)
replace the Precision and Accuracy Section statement with the following:
Precision and Accuracy
An interlaboratory study on metal analyses by this method was
conducted by the Quality Assurance Branch (QAB) of the Environmental
Monitoring Systems Laboratory--Cincinnati (EMSL-CI). Synthetic
concentrates containing various levels of this element were added to
reagent water, surface water, drinking water and three effluents. These
samples were digested by the total digestion procedure, 4.1.3 in this
manual. Results for the reagent water are given below. Results for other
water types and study details are found in ``EPA Method Study 31, Trace
Metals by Atomic Absorption (Furnace Techniques),'' National Technical
Information Service, 5285 Port Royal Road, Springfield, VA 22161 Order
No. PB 86-121 704/AS, by Copeland, F.R. and Maney, J.P., January 1986.
For a concentration range of 0.51-189 [micro]g/L
X = 1.6710(C) + 1.485
S = 0.6740(X) - 0.342
SR = 0.3895(X)- 0.384
Where:
C = True Value for the Concentration, [micro]g/L
X = Mean Recovery, [micro]g/L
S = Multi-laboratory Standard Deviation, [micro]g/L
SR = Single-analyst Standard Deviation, [micro]g/L
[77 FR 29833, May 18, 2012]
PART 140_MARINE SANITATION DEVICE STANDARD--Table of Contents
Sec.
140.1 Definitions.
140.2 Scope of standard.
140.3 Standard.
140.4 Complete prohibition.
140.5 Analytical procedures.
Authority: 33 U.S.C. 1322, as amended.
Source: 41 FR 4453, Jan. 29, 1976, unless otherwise noted.
Sec. 140.1 Definitions.
For the purpose of these standards the following definitions shall
apply:
(a) Sewage means human body wastes and the wastes from toilets and
other receptacles intended to receive or retain body wastes;
(b) Discharge includes, but is not limited to, any spilling,
leaking, pumping, pouring, emitting, emptying, or dumping;
(c) Marine sanitation device includes any equipment for installation
onboard a vessel and which is designed to receive, retain, treat, or
discharge sewage and any process to treat such sewage;
(d) Vessel includes every description of watercraft or other
artificial contrivance used, or capable of being used,
[[Page 421]]
as a means of transportation on waters of the United States;
(e) New vessel refers to any vessel on which construction was
initiated on or after January 30, 1975;
(f) Existing vessel refers to any vessel on which construction was
initiated before January 30, 1975;
(g) Fecal coliform bacteria are those organisms associated with the
intestines of warm-blooded animals that are commonly used to indicate
the presence of fecal material and the potential presence of organisms
capable of causing human disease.
Sec. 140.2 Scope of standard.
The standard adopted herein applies only to vessels on which a
marine sanitation device has been installed. The standard does not
require the installation of a marine sanitation device on any vessel
that is not so equipped. The standard applies to vessels owned and
operated by the United States unless the Secretary of Defense finds that
compliance would not be in the interest of national security.
Sec. 140.3 Standard.
(a) (1) In freshwater lakes, freshwater reservoirs or other
freshwater impoundments whose inlets or outlets are such as to prevent
the ingress or egress by vessel traffic subject to this regulation, or
in rivers not capable of navigation by interstate vessel traffic subject
to this regulation, marine sanitation devices certified by the U.S.
Coast Guard (see 33 CFR part 159, published in 40 FR 4622, January 30,
1975), installed on all vessels shall be designed and operated to
prevent the overboard discharge of sewage, treated or untreated, or of
any waste derived from sewage. This shall not be construed to prohibit
the carriage of Coast Guard-certified flow-through treatment devices
which have been secured so as to prevent such discharges.
(2) In all other waters, Coast Guard-certified marine sanitation
devices installed on all vessels shall be designed and operated to
either retain, dispose of, or discharge sewage. If the device has a
discharge, subject to paragraph (d) of this section, the effluent shall
not have a fecal coliform bacterial count of greater than 1,000 per 100
milliliters nor visible floating solids. Waters where a Coast Guard-
certified marine sanitation device permitting discharge is allowed
include coastal waters and estuaries, the Great Lakes and inter-
connected waterways, fresh-water lakes and impoundments accessible
through locks, and other flowing waters that are navigable interstate by
vessels subject to this regulation.
(b) This standard shall become effective on January 30, 1977 for new
vessels and on January 30, 1980 for existing vessels (or, in the case of
vessels owned and operated by the Department of Defense, two years and
five years, for new and existing vessels, respectively, after
promulgation of implementing regulations by the Secretary of Defense
under section 312(d) of the Act).
(c) Any vessel which is equipped as of the date of promulgation of
this regulation with a Coast Guard-certified flow-through marine
sanitation device meeting the requirements of paragraph (a)(2) of this
section, shall not be required to comply with the provisions designed to
prevent the overboard discharge of sewage, treated or untreated, in
paragraph (a)(1) of this section, for the operable life of that device.
(d) After January 30, 1980, subject to paragraphs (e) and (f) of
this section, marine sanitation devices on all vessels on waters that
are not subject to a prohibition of the overboard discharge of sewage,
treated or untreated, as specified in paragraph (a)(1) of this section,
shall be designed and operated to either retain, dispose of, or
discharge sewage, and shall be certified by the U.S. Coast Guard. If the
device has a discharge, the effluent shall not have a fecal coliform
bacterial count of greater than 200 per 100 milliliters, nor suspended
solids greater than 150 mg/1.
(e) Any existing vessel on waters not subject to a prohibition of
the overboard discharge of sewage in paragraph (a)(1) of this section,
and which is equipped with a certified device on or before January 30,
1978, shall not be required to comply with paragraph (d) of this
section, for the operable life of that device.
(f) Any new vessel on waters not subject to the prohibition of the
overboard discharge of sewage in paragraph (a)(1)
[[Page 422]]
of this section, and on which construction is initiated before January
31, 1980, which is equipped with a marine sanitation device before
January 31, 1980, certified under paragraph (a)(2) of this section,
shall not be required to comply with paragraph (d) of this section, for
the operable life of that device.
(g) The degrees of treatment described in paragraphs (a) and (d) of
this section are ``appropriate standards'' for purposes of Coast Guard
and Department of Defense certification pursuant to section 312(g)(2) of
the Act.
[41 FR 4453, Jan. 29, 1976, as amended at 60 FR 33932, June 29, 1995]
Sec. 140.4 Complete prohibition.
(a) Prohibition pursuant to CWA section 312(f)(3): a State may
completely prohibit the discharge from all vessels of any sewage,
whether treated or not, into some or all of the waters within such State
by making a written application to the Administrator, Environmental
Protection Agency, and by receiving the Administrator's affirmative
determination pursuant to section 312(f)(3) of the Act. Upon receipt of
an application under section 312(f)(3) of the Act, the Administrator
will determine within 90 days whether adequate facilities for the safe
and sanitary removal and treatment of sewage from all vessels using such
waters are reasonably available. Applications made by States pursuant to
section 312(f)(3) of the Act shall include:
(1) A certification that the protection and enhancement of the
waters described in the petition require greater environmental
protection than the applicable Federal standard;
(2) A map showing the location of commercial and recreational pump-
out facilities;
(3) A description of the location of pump-out facilities within
waters designated for no discharge;
(4) The general schedule of operating hours of the pump-out
facilities;
(5) The draught requirements on vessels that may be excluded because
of insufficient water depth adjacent to the facility;
(6) Information indicating that treatment of wastes from such pump-
out facilities is in conformance with Federal law; and
(7) Information on vessel population and vessel usage of the subject
waters.
(b) Prohibition pursuant to CWA section 312(f)(4)(A): a State may
make a written application to the Administrator, Environmental
Protection Agency, under section 312(f)(4)(A) of the Act, for the
issuance of a regulation completely prohibiting discharge from a vessel
of any sewage, whether treated or not, into particular waters of the
United States or specified portions thereof, which waters are located
within the boundaries of such State. Such application shall specify with
particularly the waters, or portions thereof, for which a complete
prohibition is desired. The application shall include identification of
water recreational areas, drinking water intakes, aquatic sanctuaries,
identifiable fish-spawning and nursery areas, and areas of intensive
boating activities. If, on the basis of the State's application and any
other information available to him, the Administrator is unable to make
a finding that the waters listed in the application require a complete
prohibition of any discharge in the waters or portions thereof covered
by the application, he shall state the reasons why he cannot make such a
finding, and shall deny the application. If the Administrator makes a
finding that the waters listed in the application require a complete
prohibition of any discharge in all or any part of the waters or
portions thereof covered by the State's application, he shall publish
notice of such findings together with a notice of proposed rule making,
and then shall proceed in accordance with 5 U.S.C. 553. If the
Administrator's finding is that applicable water quality standards
require a complete prohibition covering a more restricted or more
expanded area than that applied for by the State, he shall state the
reasons why his finding differs in scope from that requested in the
State's application.
(1) For the following waters the discharge from a vessel of any
sewage (whether treated or not) is completely prohibited pursuant to CWA
section 312(f)(4)(A):
[[Page 423]]
(i) Boundary Waters Canoe Area, formerly designated as the Superior,
Little Indian Sioux, and Caribou Roadless Areas, in the Superior
National Forest, Minnesota, as described in 16 U.S.C. 577-577d1.
(ii) Waters of the State of Florida within the boundaries of the
Florida Keys National Marine Sanctuary as delineated on a map of the
Sanctuary at http://www.fknms.nos.noaa.gov/.
(2)(i) For the marine waters of the State of California, the
following vessels are completely prohibited from discharging any sewage
(whether treated or not):
(A) A large passenger vessel;
(B) A large oceangoing vessel equipped with a holding tank which has
not fully used the holding tank's capacity, or which contains more than
de minimis amounts of sewage generated while the vessel was outside of
the marine waters of the State of California.
(ii) For purposes of paragraph (b)(2) of this section:
(A) ``Marine waters of the State of California'' means the
territorial sea measured from the baseline as determined in accordance
with the Convention on the Territorial Sea and the Contiguous Zone and
extending seaward a distance of three miles, and all enclosed bays and
estuaries subject to tidal influences from the Oregon border (41.999325
North Latitude, 124.212110 West Longitude, decimal degrees, NAD 1983) to
the Mexican border (32.471231 North Latitude, 117.137814 West Longitude,
decimal degrees, NAD 1983). A map illustrating these waters can be
obtained from EPA or viewed at http://www.epa.gov/region9/water/no-
discharge/overview.html.
(B) A ``large passenger vessel'' means a passenger vessel, as
defined in section 2101(22) of title 46, United States Code, of 300
gross tons or more, as measured under the International Convention on
Tonnage Measurement of Ships, 1969, measurement system in 46 U.S.C.
14302, or the regulatory measurement system of 46 U.S.C. 14502 for
vessels not measured under 46 U.S.C. 14302, that has berths or overnight
accommodations for passengers.
(C) A ``large oceangoing vessel'' means a private, commercial,
government, or military vessel of 300 gross tons or more, as measured
under the International Convention on Tonnage Measurement of Ships,
1969, measurement system in 46 U.S.C. 14302, or the regulatory
measurement system of 46 U.S.C. 14502 for vessels not measured under 46
U.S.C.14302, that is not a large passenger vessel.
(D) A ``holding tank'' means a tank specifically designed,
constructed, and fitted for the retention of treated or untreated
sewage, that has been designated and approved by the ship's flag
Administration on the ship's stability plan; a designated ballast tank
is not a holding tank for this purpose.
(c)(1) Prohibition pursuant to CWA section 312(f)(4)(B): A State may
make written application to the Administrator of the Environmental
Protection Agency under section 312(f)(4)(B) of the Act for the issuance
of a regulation establishing a drinking water intake no discharge zone
which completely prohibits discharge from a vessel of any sewage,
whether treated or untreated, into that zone in particular waters, or
portions thereof, within such State. Such application shall:
(i) Identify and describe exactly and in detail the location of the
drinking water supply intake(s) and the community served by the
intake(s), including average and maximum expected amounts of inflow;
(ii) Specify and describe exactly and in detail, the waters, or
portions thereof, for which a complete prohibition is desired, and where
appropriate, average, maximum and low flows in million gallons per day
(MGD) or the metric equivalent;
(iii) Include a map, either a USGS topographic quadrant map or a
NOAA nautical chart, as applicable, clearly marking by latitude and
longitude the waters or portions thereof to be designated a drinking
water intake zone; and
(iv) Include a statement of basis justifying the size of the
requested drinking water intake zone, for example, identifying areas of
intensive boating activities.
(2) If the Administrator finds that a complete prohibition is
appropriate under this paragraph, he or she shall publish notice of such
finding together
[[Page 424]]
with a notice of proposed rulemaking, and then shall proceed in
accordance with 5 U.S.C. 553. If the Administrator's finding is that a
complete prohibition covering a more restricted or more expanded area
than that applied for by the State is appropriate, he or she shall also
include a statement of the reasons why the finding differs in scope from
that requested in the State's application.
(3) If the Administrator finds that a complete prohibition is
inappropriate under this paragraph, he or she shall deny the application
and state the reasons for such denial.
(4) For the following waters the discharge from a vessel of any
sewage, whether treated or not, is completely prohibited pursuant to CWA
section 312(f)(4)(B):
(i) Two portions of the Hudson River in New York State, the first is
bounded by an east-west line through the most northern confluence of the
Mohawk River which will be designated by the Troy-Waterford Bridge
(126th Street Bridge) on the south and Lock 2 on the north, and the
second of which is bounded on the north by the southern end of
Houghtaling Island and on the south by a line between the Village of
Roseton on the western shore and Low Point on the eastern shore in the
vicinity of Chelsea, as described in Items 2 and 3 of 6 NYCRR Part
858.4.
(ii) [Reserved]
[41 FR 4453, Jan. 29, 1976, as amended at 42 FR 43837, Aug. 31, 1977; 60
FR 63945, Dec. 13, 1995; 63 FR 1320, Jan. 8, 1998; 67 FR 35743, May 21,
2002; 77 FR 11411, Feb. 27, 2012]
Sec. 140.5 Analytical procedures.
In determining the composition and quality of effluent discharge
from marine sanitation devices, the procedures contained in 40 CFR part
136, ``Guidelines Establishing Test Procedures for the Analysis of
Pollutants,'' or subsequent revisions or amendments thereto, shall be
employed.
PART 141_NATIONAL PRIMARY DRINKING WATER REGULATIONS--Table of Contents
Subpart A_General
Sec.
141.1 Applicability.
141.2 Definitions.
141.3 Coverage.
141.4 Variances and exemptions.
141.5 Siting requirements.
141.6 Effective dates.
Subpart B_Maximum Contaminant Levels
141.11 Maximum contaminant levels for inorganic chemicals.
141.12 [Reserved]
141.13 Maximum contaminant levels for turbidity.
Subpart C_Monitoring and Analytical Requirements
141.21 Coliform sampling.
141.22 Turbidity sampling and analytical requirements.
141.23 Inorganic chemical sampling and analytical requirements.
141.24 Organic chemicals, sampling and analytical requirements.
141.25 Analytical methods for radioactivity.
141.26 Monitoring frequency and compliance requirements for
radionuclides in community water systems
141.27 Alternate analytical techniques.
141.28 Certified laboratories.
141.29 Monitoring of consecutive public water systems.
Appendix A to Subpart C of Part 141--Alternative Testing Methods
Approved for Analyses Under the Safe Drinking Water Act
Subpart D_Reporting and Recordkeeping
141.31 Reporting requirements.
141.32 [Reserved]
141.33 Record maintenance.
141.34 [Reserved]
141.35 Reporting for unregulated contaminant monitoring results.
Subpart E_Special Regulations, Including Monitoring Regulations and
Prohibition on Lead Use
141.40 Monitoring requirements for unregulated contaminants.
141.41 Special monitoring for sodium.
141.42 Special monitoring for corrosivity characteristics.
141.43 Prohibition on use of lead pipes, solder, and flux.
Subpart F_Maximum Contaminant Level Goals and Maximum Residual
Disinfectant Level Goals
141.50 Maximum contaminant level goals for organic contaminants.
141.51 Maximum contaminant level goals for inorganic contaminants.
[[Page 425]]
141.52 Maximum contaminant level goals for microbiological contaminants.
141.53 Maximum contaminant level goals for disinfection byproducts.
141.54 Maximum residual disinfectant level goals for disinfectants.
141.55 Maximum contaminant level goals for radionuclides.
Subpart G_National Primary Drinking Water Regulations: Maximum
Contaminant Levels and Maximum Residual Disinfectant Levels
141.60 Effective dates.
141.61 Maximum contaminant levels for organic contaminants.
141.62 Maximum contaminant levels for inorganic contaminants.
141.63 Maximum contaminant levels (MCLs) for microbiological
contaminants.
141.64 Maximum contaminant levels for disinfection byproducts.
141.65 Maximum residual disinfectant levels.
141.66 Maximum contaminant levels for radionuclides.
Subpart H_Filtration and Disinfection
141.70 General requirements.
141.71 Criteria for avoiding filtration.
141.72 Disinfection.
141.73 Filtration.
141.74 Analytical and monitoring requirements.
141.75 Reporting and recordkeeping requirements.
141.76 Recycle provisions.
Subpart I_Control of Lead and Copper
141.80 General requirements.
141.81 Applicability of corrosion control treatment steps to small,
medium-size and large water systems.
141.82 Description of corrosion control treatment requirements.
141.83 Source water treatment requirements.
141.84 Lead service line replacement requirements.
141.85 Public education and supplemental monitoring requirements.
141.86 Monitoring requirements for lead and copper in tap water.
141.87 Monitoring requirements for water quality parameters.
141.88 Monitoring requirements for lead and copper in source water.
141.89 Analytical methods.
141.90 Reporting requirements.
141.91 Recordkeeping requirements.
Subpart J_Use of Non-Centralized Treatment Devices
141.100 Criteria and procedures for public water systems using point-of-
entry devices.
141.101 Use of bottled water.
Subpart K_Treatment Techniques
141.110 General requirements.
141.111 Treatment techniques for acrylamide and epichlorohydrin.
Subpart L_Disinfectant Residuals, Disinfection Byproducts, and
Disinfection Byproduct Precursors
141.130 General requirements.
141.131 Analytical requirements.
141.132 Monitoring requirements.
141.133 Compliance requirements.
141.134 Reporting and recordkeeping requirements.
141.135 Treatment technique for control of disinfection byproduct (DBP)
precursors.
Subparts M-N [Reserved]
Subpart O_Consumer Confidence Reports
141.151 Purpose and applicability of this subpart.
141.152 Effective dates.
141.153 Content of the reports.
141.154 Required additional health information.
141.155 Report delivery and recordkeeping.
Appendix A to Subpart O of Part 141--Regulated Contaminants
Subpart P_Enhanced Filtration and Disinfection_Systems Serving 10,000 or
More People
141.170 General requirements.
141.171 Criteria for avoiding filtration.
141.172 Disinfection profiling and benchmarking.
141.173 Filtration.
141.174 Filtration sampling requirements.
141.175 Reporting and recordkeeping requirements.
Subpart Q_Public Notification of Drinking Water Violations
141.201 General public notification requirements.
141.202 Tier 1 Public Notice--Form, manner, and frequency of notice.
141.203 Tier 2 Public Notice--Form, manner, and frequency of notice.
141.204 Tier 3 Public Notice--Form, manner, and frequency of notice.
141.205 Content of the public notice.
[[Page 426]]
141.206 Notice to new billing units or new customers.
141.207 Special notice of the availability of unregulated contaminant
monitoring results.
141.208 Special notice for exceedance of the SMCL for fluoride.
141.209 Special notice for nitrate exceedances above MCL by non-
community water systems (NCWS), where granted permission by
the primacy agency under Sec. 141.11(d).
141.210 Notice by primacy agency on behalf of the public water system.
141.211 Special notice for repeated failure to conduct monitoring of the
source water for Cryptosporidium and for failure to determine
bin classification or mean Cryptosporidium level.
Appendix A to Subpart Q of Part 141--NPDWR Violations and Situations
Requiring Public Notice
Appendix B to Subpart Q of Part 141--Standard Health Effects Language
for Public Notification
Appendix C to Subpart Q of Part 141--List of Acronyms Used in Public
Notification Regulation
Subpart R [Reserved]
Subpart S_Ground Water Rule
141.400 General requirements and applicability.
141.401 Sanitary surveys for ground water systems.
141.402 Ground water source microbial monitoring and analytical methods.
141.403 Treatment technique requirements for ground water systems.
141.404 Treatment technique violations for ground water systems.
141.405 Reporting and recordkeeping for ground water systems.
Subpart T_Enhanced Filtration and Disinfection_Systems Serving Fewer
Than 10,000 People
General Requirements
141.500 General requirements.
141.501 Who is subject to the requirements of subpart T?
141.502 When must my system comply with these requirements?
141.503 What does subpart T require?
Finished Water Reservoirs
141.510 Is my system subject to the new finished water reservoir
requirements?
141.511 What is required of new finished water reservoirs?
Additional Watershed Control Requirements for Unfiltered Systems
141.520 Is my system subject to the updated watershed control
requirements?
141.521 What updated watershed control requirements must my unfiltered
system implement to continue to avoid filtration?
141.522 How does the State determine whether my system's watershed
control requirements are adequate?
Disinfection Profile
141.530 What is a disinfection profile and who must develop one?
141.531 What criteria must a State use to determine that a profile is
unnecessary?
141.532 How does my system develop a disinfection profile and when must
it begin?
141.533 What data must my system collect to calculate a disinfection
profile?
141.534 How does my system use this data to calculate an inactivation
ratio?
141.535 What if my system uses chloramines, ozone, or chlorine dioxide
for primary disinfection?
141.536 My system has developed an inactivation ratio; what must we do
now?
Disinfection Benchmark
141.540 Who has to develop a disinfection benchmark?
141.541 What are significant changes to disinfection practice?
141.542 What must my system do if we are considering a significant
change to disinfection practices?
141.543 How is the disinfection benchmark calculated?
141.544 What if my system uses chloramines, ozone, or chlorine dioxide
for primary disinfection?
Combined Filter Effluent Requirements
141.550 Is my system required to meet subpart T combined filter effluent
turbidity limits?
141.551 What strengthened combined filter effluent turbidity limits must
my system meet?
141.552 My system consists of ``alternative filtration'' and is required
to conduct a demonstration--what is required of my system and
how does the State establish my turbidity limits?
141.553 My system practices lime softening--is there any special
provision regarding my combined filter effluent?
Individual Filter Turbidity Requirements
141.560 Is my system subject to individual filter turbidity
requirements?
141.561 What happens if my system's turbidity monitoring equipment
fails?
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141.562 My system only has two or fewer filters--is there any special
provision regarding individual filter turbidity monitoring?
141.563 What follow-up action is my system required to take based on
continuous turbidity monitoring?
141.564 My system practices lime softening--is there any special
provision regarding my individual filter turbidity monitoring?
Reporting and Recordkeeping Requirements
141.570 What does subpart T require that my system report to the State?
141.571 What records does subpart T require my system to keep?
Subpart U_Initial Distribution System Evaluations
141.600 General requirements.
141.601 Standard monitoring.
141.602 System specific studies.
141.603 40/30 certification.
141.604 Very small system waivers.
141.605 Subpart V compliance monitoring location recommendations.
Subpart V_Stage 2 Disinfection Byproducts Requirements
141.620 General requirements.
141.621 Routine monitoring.
141.622 Subpart V monitoring plan.
141.623 Reduced monitoring.
141.624 Additional requirements for consecutive systems.
141.625 Conditions requiring increased monitoring.
141.626 Operational evaluation levels.
141.627 Requirements for remaining on reduced TTHM and HAA5 monitoring
based on subpart L results.
141.628 Requirements for remaining on increased TTHM and HAA5 monitoring
based on subpart L results.
141.629 Reporting and recordkeeping requirements.
Subpart W_Enhanced Treatment for Cryptosporidium
General Requirements
141.700 General requirements.
Source Water Monitoring Requirements
141.701 Source water monitoring.
141.702 Sampling schedules.
141.703 Sampling locations.
141.704 Analytical methods.
141.705 Approved laboratories.
141.706 Reporting source water monitoring results.
141.707 Grandfathering previously collected data.
Disinfection Profiling and Benchmarking Requirements
141.708 Requirements when making a significant change in disinfection
practice.
141.709 Developing the disinfection profile and benchmark.
Treatment Technique Requirements
141.710 Bin classification for filtered systems.
141.711 Filtered system additional Cryptosporidium treatment
requirements.
141.712 Unfiltered system Cryptosporidium treatment requirements.
141.713 Schedule for compliance with Cryptosporidium treatment
requirements.
141.714 Requirements for uncovered finished water storage facilities.
Requirements for Microbial Toolbox Components
141.715 Microbial toolbox options for meeting Cryptosporidium treatment
requirements.
141.716 Source toolbox components.
141.717 Pre-filtration treatment toolbox components.
141.718 Treatment performance toolbox components.
141.719 Additional filtration toolbox components.
141.720 Inactivation toolbox components.
Reporting and Recordkeeping Requirements
141.721 Reporting requirements.
141.722 Recordkeeping requirements.
Requirements for Sanitary Surveys Performed by EPA
141.723 Requirements to respond to significant deficiencies identified
in sanitary surveys performed by EPA.
Subpart X_Aircraft Drinking Water Rule
141.800 Applicability and compliance date.
141.801 Definitions.
141.802 Coliform sampling plan.
141.803 Coliform sampling.
141.804 Aircraft water system operations and maintenance plan.
141.805 Notification to passengers and crew.
141.806 Reporting requirements.
141.807 Recordkeeping requirements.
141.808 Audits and inspections.
141.809 Supplemental treatment.
141.810 Violations.
Subpart Y_Revised Total Coliform Rule
141.851 General.
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141.852 Analytical methods and laboratory certification.
141.853 General monitoring requirements for all public water systems.
141.854 Routine monitoring requirements for non-community water systems
serving 1,000 or fewer people using only ground water.
141.855 Routine monitoring requirements for community water systems
serving 1,000 or fewer people using only ground water.
141.856 Routine monitoring requirements for subpart H public water
systems serving 1,000 or fewer people.
141.857 Routine monitoring requirements for public water systems serving
more than 1,000 people.
141.858 Repeat monitoring and E. coli requirements.
141.859 Coliform treatment technique triggers and assessment
requirements for protection against potential fecal
contamination.
141.860 Violations.
141.861 Reporting and recordkeeping.
Authority: 42 U.S.C. 300f, 300g-1, 300g-2, 300g-3, 300g-4, 300g-5,
300g-6, 300j-4, 300j-9, and 300j-11.
Source: 40 FR 59570, Dec. 24, 1975, unless otherwise noted.
Editorial Note: Nomenclature changes to part 141 appear at 69 FR
18803, Apr. 9, 2004.
Note: For community water systems serving 75,000 or more persons,
monitoring must begin 1 year following promulation and the effective
date of the MCL is 2 years following promulgation. For community water
systems serving 10,000 to 75,000 persons, monitoring must begin within 3
years from the date of promulgation and the effective date of the MCL is
4 years from the date of promulgation. Effective immediately, systems
that plan to make significant modifications to their treatment processes
for the purpose of complying with the TTHM MCL are required to seek and
obtain State approval of their treatment modification plans. This note
affects Sec. Sec. 141.2, 141.6, 141.12, 141.24 and 141.30. For
additional information see 44 FR 68641, Nov. 29, 1979.
Subpart A_General
Sec. 141.1 Applicability.
This part establishes primary drinking water regulations pursuant to
section 1412 of the Public Health Service Act, as amended by the Safe
Drinking Water Act (Pub. L. 93-523); and related regulations applicable
to public water systems.
Sec. 141.2 Definitions.
As used in this part, the term:
Act means the Public Health Service Act, as amended by the Safe
Drinking Water Act, Public Law 93-523.
Action level, is the concentration of lead or copper in water
specified in Sec. 141.80(c) which determines, in some cases, the
treatment requirements contained in subpart I of this part that a water
system is required to complete.
Bag filters are pressure-driven separation devices that remove
particulate matter larger than 1 micrometer using an engineered porous
filtration media. They are typically constructed of a non-rigid, fabric
filtration media housed in a pressure vessel in which the direction of
flow is from the inside of the bag to outside.
Bank filtration is a water treatment process that uses a well to
recover surface water that has naturally infiltrated into ground water
through a river bed or bank(s). Infiltration is typically enhanced by
the hydraulic gradient imposed by a nearby pumping water supply or other
well(s).
Best available technology or BAT means the best technology,
treatment techniques, or other means which the Administrator finds,
after examination for efficacy under field conditions and not solely
under laboratory conditions, are available (taking cost into
consideration). For the purposes of setting MCLs for synthetic organic
chemicals, any BAT must be at least as effective as granular activated
carbon.
Cartridge filters are pressure-driven separation devices that remove
particulate matter larger than 1 micrometer using an engineered porous
filtration media. They are typically constructed as rigid or semi-rigid,
self-supporting filter elements housed in pressure vessels in which flow
is from the outside of the cartridge to the inside.
Clean compliance history is, for the purposes of subpart Y, a record
of no MCL violations under Sec. 141.63; no monitoring violations under
Sec. 141.21 or subpart Y; and no coliform treatment technique trigger
exceedances or treatment technique violations under subpart Y.
Coagulation means a process using coagulant chemicals and mixing by
which colloidal and suspended materials are
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destabilized and agglomerated into flocs.
Combined distribution system is the interconnected distribution
system consisting of the distribution systems of wholesale systems and
of the consecutive systems that receive finished water.
Community water system means a public water system which serves at
least 15 service connections used by year-round residents or regularly
serves at least 25 year-round residents.
Compliance cycle means the nine-year calendar year cycle during
which public water systems must monitor. Each compliance cycle consists
of three three-year compliance periods. The first calendar year cycle
begins January 1, 1993 and ends December 31, 2001; the second begins
January 1, 2002 and ends December 31, 2010; the third begins January 1,
2011 and ends December 31, 2019.
Compliance period means a three-year calendar year period within a
compliance cycle. Each compliance cycle has three three-year compliance
periods. Within the first compliance cycle, the first compliance period
runs from January 1, 1993 to December 31, 1995; the second from January
1, 1996 to December 31, 1998; the third from January 1, 1999 to December
31, 2001.
Comprehensive performance evaluation (CPE) is a thorough review and
analysis of a treatment plant's performance-based capabilities and
associated administrative, operation and maintenance practices. It is
conducted to identify factors that may be adversely impacting a plant's
capability to achieve compliance and emphasizes approaches that can be
implemented without significant capital improvements. For purpose of
compliance with subparts P and T of this part, the comprehensive
performance evaluation must consist of at least the following
components: Assessment of plant performance; evaluation of major unit
processes; identification and prioritization of performance limiting
factors; assessment of the applicability of comprehensive technical
assistance; and preparation of a CPE report.
Confluent growth means a continuous bacterial growth covering the
entire filtration area of a membrane filter, or a portion thereof, in
which bacterial colonies are not discrete.
Consecutive system is a public water system that receives some or
all of its finished water from one or more wholesale systems. Delivery
may be through a direct connection or through the distribution system of
one or more consecutive systems.
Contaminant means any physical, chemical, biological, or
radiological substance or matter in water.
Conventional filtration treatment means a series of processes
including coagulation, flocculation, sedimentation, and filtration
resulting in substantial particulate removal.
Corrosion inhibitor means a substance capable of reducing the
corrosivity of water toward metal plumbing materials, especially lead
and copper, by forming a protective film on the interior surface of
those materials.
CT or CTcalc is the product of ``residual disinfectant
concentration'' (C) in mg/1 determined before or at the first customer,
and the corresponding ``disinfectant contact time'' (T) in minutes,
i.e., ``C'' x ``T''. If a public water system applies disinfectants at
more than one point prior to the first customer, it must determine the
CT of each disinfectant sequence before or at the first customer to
determine the total percent inactivation or ``total inactivation
ratio.'' In determining the total inactivation ratio, the public water
system must determine the residual disinfectant concentration of each
disinfection sequence and corresponding contact time before any
subsequent disinfection application point(s). ``CT99.9'' is
the CT value required for 99.9 percent (3-log) inactivation of Giardia
lamblia cysts. CT99.9 for a variety of disinfectants and
conditions appear in tables 1.1-1.6, 2.1, and 3.1 of Sec. 141.74(b)(3).
[GRAPHIC] [TIFF OMITTED] TC15NO91.129
is the inactivation ratio. The sum of the inactivation ratios, or total
inactivation ratio shown as
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[GRAPHIC] [TIFF OMITTED] TC15NO91.130
is calculated by adding together the inactivation ratio for each
disinfection sequence. A total inactivation ratio equal to or greater
than 1.0 is assumed to provide a 3-log inactivation of Giardia lamblia
cysts.
Diatomaceous earth filtration means a process resulting in
substantial particulate removal in which (1) a precoat cake of
diatomaceous earth filter media is deposited on a support membrance
(septum), and (2) while the water is filtered by passing through the
cake on the septum, additional filter media known as body feed is
continuously added to the feed water to maintain the permeability of the
filter cake.
Direct filtration means a series of processes including coagulation
and filtration but excluding sedimentation resulting in substantial
particulate removal.
Disinfectant means any oxidant, including but not limited to
chlorine, chlorine dioxide, chloramines, and ozone added to water in any
part of the treatment or distribution process, that is intended to kill
or inactivate pathogenic microorganisms.
Disinfectant contact time (``T'' in CT calculations) means the time
in minutes that it takes for water to move from the point of
disinfectant application or the previous point of disinfectant residual
measurement to a point before or at the point where residual
disinfectant concentration (``C'') is measured. Where only one ``C'' is
measured, ``T'' is the time in minutes that it takes for water to move
from the point of disinfectant application to a point before or at where
residual disinfectant concentration (``C'') is measured. Where more than
one ``C'' is measured, ``T'' is (a) for the first measurement of ``C'',
the time in minutes that it takes for water to move from the first or
only point of disinfectant application to a point before or at the point
where the first ``C'' is measured and (b) for subsequent measurements of
``C'', the time in minutes that it takes for water to move from the
previous ``C'' measurement point to the ``C'' measurement point for
which the particular ``T'' is being calculated. Disinfectant contact
time in pipelines must be calculated based on ``plug flow'' by dividing
the internal volume of the pipe by the maximum hourly flow rate through
that pipe. Disinfectant contact time within mixing basins and storage
reservoirs must be determined by tracer studies or an equivalent
demonstration.
Disinfection means a process which inactivates pathogenic organisms
in water by chemical oxidants or equivalent agents.
Disinfection profile is a summary of Giardia lamblia inactivation
through the treatment plant. The procedure for developing a disinfection
profile is contained in Sec. 141.172 (Disinfection profiling and
benchmarking) in subpart P and Sec. Sec. 141.530-141.536 (Disinfection
profile) in subpart T of this part.
Domestic or other non-distribution system plumbing problem means a
coliform contamination problem in a public water system with more than
one service connection that is limited to the specific service
connection from which the coliform-positive sample was taken.
Dose equivalent means the product of the absorbed dose from ionizing
radiation and such factors as account for differences in biological
effectiveness due to the type of radiation and its distribution in the
body as specified by the International Commission on Radiological Units
and Measurements (ICRU).
Dual sample set is a set of two samples collected at the same time
and same location, with one sample analyzed for TTHM and the other
sample analyzed for HAA5. Dual sample sets are collected for the
purposes of conducting an IDSE under subpart U of this part and
determining compliance with the TTHM and HAA5 MCLs under subpart V of
this part.
Effective corrosion inhibitor residual, for the purpose of subpart I
of this part only, means a concentration sufficient to form a
passivating film on the interior walls of a pipe.
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Enhanced coagulation means the addition of sufficient coagulant for
improved removal of disinfection byproduct precursors by conventional
filtration treatment.
Enhanced softening means the improved removal of disinfection
byproduct precursors by precipitative softening.
Filter profile is a graphical representation of individual filter
performance, based on continuous turbidity measurements or total
particle counts versus time for an entire filter run, from startup to
backwash inclusively, that includes an assessment of filter performance
while another filter is being backwashed.
Filtration means a process for removing particulate matter from
water by passage through porous media.
Finished water is water that is introduced into the distribution
system of a public water system and is intended for distribution and
consumption without further treatment, except as treatment necessary to
maintain water quality in the distribution system (e.g., booster
disinfection, addition of corrosion control chemicals).
First draw sample means a one-liter sample of tap water, collected
in accordance with Sec. 141.86(b)(2), that has been standing in
plumbing pipes at least 6 hours and is collected without flushing the
tap.
Flocculation means a process to enhance agglomeration or collection
of smaller floc particles into larger, more easily settleable particles
through gentle stirring by hydraulic or mechanical means.
Flowing stream is a course of running water flowing in a definite
channel.
GAC10 means granular activated carbon filter beds with an empty-bed
contact time of 10 minutes based on average daily flow and a carbon
reactivation frequency of every 180 days, except that the reactivation
frequency for GAC10 used as a best available technology for compliance
with subpart V MCLs under Sec. 141.64(b)(2) shall be 120 days.
GAC20 means granular activated carbon filter beds with an empty-bed
contact time of 20 minutes based on average daily flow and a carbon
reactivation frequency of every 240 days.
Ground water under the direct influence of surface water (GWUDI)
means any water beneath the surface of the ground with significant
occurrence of insects or other macroorganisms, algae, or large-diameter
pathogens such as Giardia lamblia or Cryptosporidium, or significant and
relatively rapid shifts in water characteristics such as turbidity,
temperature, conductivity, or pH which closely correlate to
climatological or surface water conditions. Direct influence must be
determined for individual sources in accordance with criteria
established by the State. The State determination of direct influence
may be based on site-specific measurements of water quality and/or
documentation of well construction characteristics and geology with
field evaluation.
Gross alpha particle activity means the total radioactivity due to
alpha particle emission as inferred from measurements on a dry sample.
Gross beta particle activity means the total radioactivity due to
beta particle emission as inferred from measurements on a dry sample.
Haloacetic acids (five) (HAA5) mean the sum of the concentrations in
milligrams per liter of the haloacetic acid compounds (monochloroacetic
acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid,
and dibromoacetic acid), rounded to two significant figures after
addition.
Halogen means one of the chemical elements chlorine, bromine or
iodine.
Initial compliance period means the first full three-year compliance
period which begins at least 18 months after promulgation, except for
contaminants listed at Sec. 141.61(a) (19)-(21), (c) (19)-(33), and
Sec. 141.62(b) (11)-(15), initial compliance period means the first
full three-year compliance period after promulgation for systems with
150 or more service connections (January 1993-December 1995), and first
full three-year compliance period after the effective date of the
regulation (January 1996-December 1998) for systems having fewer than
150 service connections.
Lake/reservoir refers to a natural or man made basin or hollow on
the Earth's surface in which water collects or is stored that may or may
not have a current or single direction of flow.
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Large water system, for the purpose of subpart I of this part only,
means a water system that serves more than 50,000 persons.
Lead service line means a service line made of lead which connects
the water main to the building inlet and any lead pigtail, gooseneck or
other fitting which is connected to such lead line.
Legionella means a genus of bacteria, some species of which have
caused a type of pneumonia called Legionnaires Disease.
Level 1 assessment is an evaluation to identify the possible
presence of sanitary defects, defects in distribution system coliform
monitoring practices, and (when possible) the likely reason that the
system triggered the assessment. It is conducted by the system operator
or owner. Minimum elements include review and identification of atypical
events that could affect distributed water quality or indicate that
distributed water quality was impaired; changes in distribution system
maintenance and operation that could affect distributed water quality
(including water storage); source and treatment considerations that bear
on distributed water quality, where appropriate (e.g., whether a ground
water system is disinfected); existing water quality monitoring data;
and inadequacies in sample sites, sampling protocol, and sample
processing. The system must conduct the assessment consistent with any
State directives that tailor specific assessment elements with respect
to the size and type of the system and the size, type, and
characteristics of the distribution system.
Level 2 assessment is an evaluation to identify the possible
presence of sanitary defects, defects in distribution system coliform
monitoring practices, and (when possible) the likely reason that the
system triggered the assessment. A Level 2 assessment provides a more
detailed examination of the system (including the system's monitoring
and operational practices) than does a Level 1 assessment through the
use of more comprehensive investigation and review of available
information, additional internal and external resources, and other
relevant practices. It is conducted by an individual approved by the
State, which may include the system operator. Minimum elements include
review and identification of atypical events that could affect
distributed water quality or indicate that distributed water quality was
impaired; changes in distribution system maintenance and operation that
could affect distributed water quality (including water storage); source
and treatment considerations that bear on distributed water quality,
where appropriate (e.g., whether a ground water system is disinfected);
existing water quality monitoring data; and inadequacies in sample
sites, sampling protocol, and sample processing. The system must conduct
the assessment consistent with any State directives that tailor specific
assessment elements with respect to the size and type of the system and
the size, type, and characteristics of the distribution system. The
system must comply with any expedited actions or additional actions
required by the State in the case of an E. coli MCL violation.
Locational running annual average (LRAA) is the average of sample
analytical results for samples taken at a particular monitoring location
during the previous four calendar quarters.
Man-made beta particle and photon emitters means all radionuclides
emitting beta particles and/or photons listed in Maximum Permissible
Body Burdens and Maximum Permissible Concentration of Radionuclides in
Air or Water for Occupational Exposure, NBS Handbook 69, except the
daughter products of thorium-232, uranium-235 and uranium-238.
Maximum contaminant level means the maximum permissable level of a
contaminant in water which is delivered to any user of a public water
system.
Maximum contaminant level goal or MCLG means the maximum level of a
contaminant in drinking water at which no known or anticipated adverse
effect on the health of persons would occur, and which allows an
adequate margin of safety. Maximum contaminant level goals are
nonenforceable health goals.
Maximum residual disinfectant level (MRDL) means a level of a
disinfectant added for water treatment that may not be exceeded at the
consumer's tap without an unacceptable possibility of
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adverse health effects. For chlorine and chloramines, a PWS is in
compliance with the MRDL when the running annual average of monthly
averages of samples taken in the distribution system, computed
quarterly, is less than or equal to the MRDL. For chlorine dioxide, a
PWS is in compliance with the MRDL when daily samples are taken at the
entrance to the distribution system and no two consecutive daily samples
exceed the MRDL. MRDLs are enforceable in the same manner as maximum
contaminant levels under Section 1412 of the Safe Drinking Water Act.
There is convincing evidence that addition of a disinfectant is
necessary for control of waterborne microbial contaminants.
Notwithstanding the MRDLs listed in Sec. 141.65, operators may increase
residual disinfectant levels of chlorine or chloramines (but not
chlorine dioxide) in the distribution system to a level and for a time
necessary to protect public health to address specific microbiological
contamination problems caused by circumstances such as distribution line
breaks, storm runoff events, source water contamination, or cross-
connections.
Maximum residual disinfectant level goal (MRDLG) means the maximum
level of a disinfectant added for water treatment at which no known or
anticipated adverse effect on the health of persons would occur, and
which allows an adequate margin of safety. MRDLGs are nonenforceable
health goals and do not reflect the benefit of the addition of the
chemical for control of waterborne microbial contaminants.
Maximum Total Trihalomethane Potential (MTP) means the maximum
concentration of total trihalomethanes produced in a given water
containing a disinfectant residual after 7 days at a temperature of 25
[deg]C or above.
Medium-size water system, for the purpose of subpart I of this part
only, means a water system that serves greater than 3,300 and less than
or equal to 50,000 persons.
Membrane filtration is a pressure or vacuum driven separation
process in which particulate matter larger than 1 micrometer is rejected
by an engineered barrier, primarily through a size-exclusion mechanism,
and which has a measurable removal efficiency of a target organism that
can be verified through the application of a direct integrity test. This
definition includes the common membrane technologies of microfiltration,
ultrafiltration, nanofiltration, and reverse osmosis.
Near the first service connection means at one of the 20 percent of
all service connections in the entire system that are nearest the water
supply treatment facility, as measured by water transport time within
the distribution system.
Non-community water system means a public water system that is not a
community water system. A non-community water system is either a
``transient non-community water system (TWS)'' or a ``non-transient non-
community water system (NTNCWS).''
Non-transient non-community water system or NTNCWS means a public
water system that is not a community water system and that regularly
serves at least 25 of the same persons over 6 months per year.
Optimal corrosion control treatment, for the purpose of subpart I of
this part only, means the corrosion control treatment that minimizes the
lead and copper concentrations at users' taps while insuring that the
treatment does not cause the water system to violate any national
primary drinking water regulations.
Performance evaluation sample means a reference sample provided to a
laboratory for the purpose of demonstrating that the laboratory can
successfully analyze the sample within limits of performance specified
by the Agency. The true value of the concentration of the reference
material is unknown to the laboratory at the time of the analysis.
Person means an individual; corporation; company; association;
partnership; municipality; or State, Federal, or tribal agency.
Picocurie (pCi) means the quantity of radioactive material producing
2.22 nuclear transformations per minute.
Plant intake refers to the works or structures at the head of a
conduit through which water is diverted from a source (e.g., river or
lake) into the treatment plant.
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Point of disinfectant application is the point where the
disinfectant is applied and water downstream of that point is not
subject to recontamination by surface water runoff.
Point-of-entry treatment device (POE) is a treatment device applied
to the drinking water entering a house or building for the purpose of
reducing contaminants in the drinking water distributed throughout the
house or building.
Point-of-use treatment device (POU) is a treatment device applied to
a single tap used for the purpose of reducing contaminants in drinking
water at that one tap.
Presedimentation is a preliminary treatment process used to remove
gravel, sand and other particulate material from the source water
through settling before the water enters the primary clarification and
filtration processes in a treatment plant.
Public water system means a system for the provision to the public
of water for human consumption through pipes or, after August 5, 1998,
other constructed conveyances, if such system has at least fifteen
service connections or regularly serves an average of at least twenty-
five individuals daily at least 60 days out of the year. Such term
includes: any collection, treatment, storage, and distribution
facilities under control of the operator of such system and used
primarily in connection with such system; and any collection or
pretreatment storage facilities not under such control which are used
primarily in connection with such system. Such term does not include any
``special irrigation district.'' A public water system is either a
``community water system'' or a ``noncommunity water system.''
Rem means the unit of dose equivalent from ionizing radiation to the
total body or any internal organ or organ system. A ``millirem (mrem)''
is \1/1000\ of a rem.
Repeat compliance period means any subsequent compliance period
after the initial compliance period.
Residual disinfectant concentration (``C'' in CT calculations) means
the concentration of disinfectant measured in mg/l in a representative
sample of water.
Sanitary defect is a defect that could provide a pathway of entry
for microbial contamination into the distribution system or that is
indicative of a failure or imminent failure in a barrier that is already
in place.
Sanitary survey means an onsite review of the water source,
facilities, equipment, operation and maintenance of a public water
system for the purpose of evaluating the adequacy of such source,
facilities, equipment, operation and maintenance for producing and
distributing safe drinking water.
Seasonal system is a non-community water system that is not operated
as a public water system on a year-round basis and starts up and shuts
down at the beginning and end of each operating season.
Sedimentation means a process for removal of solids before
filtration by gravity or separation.
Service connection, as used in the definition of public water
system, does not include a connection to a system that delivers water by
a constructed conveyance other than a pipe if:
(1) The water is used exclusively for purposes other than
residential uses (consisting of drinking, bathing, and cooking, or other
similar uses);
(2) The State determines that alternative water to achieve the
equivalent level of public health protection provided by the applicable
national primary drinking water regulation is provided for residential
or similar uses for drinking and cooking; or
(3) The State determines that the water provided for residential or
similar uses for drinking, cooking, and bathing is centrally treated or
treated at the point of entry by the provider, a pass-through entity, or
the user to achieve the equivalent level of protection provided by the
applicable national primary drinking water regulations.
Service line sample means a one-liter sample of water collected in
accordance with Sec. 141.86(b)(3), that has been standing for at least
6 hours in a service line.
Single family structure, for the purpose of subpart I of this part
only, means a building constructed as a single-family residence that is
currently used as either a residence or a place of business.
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Slow sand filtration means a process involving passage of raw water
through a bed of sand at low velocity (generally less than 0.4 m/h)
resulting in substantial particulate removal by physical and biological
mechanisms.
Small water system, for the purpose of subpart I of this part only,
means a water system that serves 3,300 persons or fewer.
Special irrigation district means an irrigation district in
existence prior to May 18, 1994 that provides primarily agricultural
service through a piped water system with only incidental residential or
similar use where the system or the residential or similar users of the
system comply with the exclusion provisions in section 1401(4)(B)(i)(II)
or (III).
Standard sample means the aliquot of finished drinking water that is
examined for the presence of coliform bacteria.
State means the agency of the State or Tribal government which has
jurisdiction over public water systems. During any period when a State
or Tribal government does not have primary enforcement responsibility
pursuant to section 1413 of the Act, the term ``State'' means the
Regional Administrator, U.S. Environmental Protection Agency.
Subpart H systems means public water systems using surface water or
ground water under the direct influence of surface water as a source
that are subject to the requirements of subpart H of this part.
Supplier of water means any person who owns or operates a public
water system.
Surface water means all water which is open to the atmosphere and
subject to surface runoff.
SUVA means Specific Ultraviolet Absorption at 254 nanometers (nm),
an indicator of the humic content of water. It is a calculated parameter
obtained by dividing a sample's ultraviolet absorption at a wavelength
of 254 nm (UV 254) (in m \ = 1\) by its concentration of
dissolved organic carbon (DOC) (in mg/L).
System with a single service connection means a system which
supplies drinking water to consumers via a single service line.
Too numerous to count means that the total number of bacterial
colonies exceeds 200 on a 47-mm diameter membrane filter used for
coliform detection.
Total Organic Carbon (TOC) means total organic carbon in mg/L
measured using heat, oxygen, ultraviolet irradiation, chemical oxidants,
or combinations of these oxidants that convert organic carbon to carbon
dioxide, rounded to two significant figures.
Total trihalomethanes (TTHM) means the sum of the concentration in
milligrams per liter of the trihalomethane compounds (trichloromethane
[chloroform], dibromochloromethane, bromodichloromethane and
tribromomethane [bromoform]), rounded to two significant figures.
Transient non-community water system or TWS means a non-community
water system that does not regularly serve at least 25 of the same
persons over six months per year.
Trihalomethane (THM) means one of the family of organic compounds,
named as derivatives of methane, wherein three of the four hydrogen
atoms in methane are each substituted by a halogen atom in the molecular
structure.
Two-stage lime softening is a process in which chemical addition and
hardness precipitation occur in each of two distinct unit clarification
processes in series prior to filtration.
Uncovered finished water storage facility is a tank, reservoir, or
other facility used to store water that will undergo no further
treatment to reduce microbial pathogens except residual disinfection and
is directly open to the atmosphere.
Virus means a virus of fecal origin which is infectious to humans by
waterborne transmission.
Waterborne disease outbreak means the significant occurrence of
acute infectious illness, epidemiologically associated with the
ingestion of water from a public water system which is deficient in
treatment, as determined by the appropriate local or State agency.
Wholesale system is a public water system that treats source water
as necessary to produce finished water and then delivers some or all of
that finished water to another public water
[[Page 436]]
system. Delivery may be through a direct connection or through the
distribution system of one or more consecutive systems.
[40 FR 59570, Dec. 24, 1975]
Editorial Note: For Federal Register citations affecting Sec.
141.2, see the List of CFR Sections Affected, which appears in the
Finding Aids section of the printed volume and at www.fdsys.gov.
Sec. 141.3 Coverage.
This part shall apply to each public water system, unless the public
water system meets all of the following conditions:
(a) Consists only of distribution and storage facilities (and does
not have any collection and treatment facilities);
(b) Obtains all of its water from, but is not owned or operated by,
a public water system to which such regulations apply:
(c) Does not sell water to any person; and
(d) Is not a carrier which conveys passengers in interstate
commerce.
Sec. 141.4 Variances and exemptions.
(a) Variances or exemptions from certain provisions of these
regulations may be granted pursuant to sections 1415 and 1416 of the Act
and subpart K of part 142 of this chapter (for small system variances)
by the entity with primary enforcement responsibility, except that
variances or exemptions from the MCLs for total coliforms and E. coli
and variances from any of the treatment technique requirements of
subpart H of this part may not be granted.
(b) EPA has stayed the effective date of this section relating to
the total coliform MCL of Sec. 141.63(a) for systems that demonstrate
to the State that the violation of the total coliform MCL is due to a
persistent growth of total coliforms in the distribution system rather
than fecal or pathogenic contamination, a treatment lapse or deficiency,
or a problem in the operation or maintenance of the distribution system.
This is stayed until March 31, 2016, at which time the total coliform
MCL is no longer effective.
Note to paragraph (a): As provided in Sec. 142.304(a), small system
variances are not available for rules addressing microbial contaminants,
which would include subparts H, P, S, T, W, and Y of this part.
[78 FR 10346, Feb. 13, 2013]
Sec. 141.5 Siting requirements.
Before a person may enter into a financial commitment for or
initiate construction of a new public water system or increase the
capacity of an existing public water system, he shall notify the State
and, to the extent practicable, avoid locating part or all of the new or
expanded facility at a site which:
(a) Is subject to a significant risk from earthquakes, floods, fires
or other disasters which could cause a breakdown of the public water
system or a portion thereof; or
(b) Except for intake structures, is within the floodplain of a 100-
year flood or is lower than any recorded high tide where appropriate
records exist. The U.S. Environmental Protection Agency will not seek to
override land use decisions affecting public water systems siting which
are made at the State or local government levels.
Sec. 141.6 Effective dates.
(a) Except as provided in paragraphs (b) through (k) of this
section, and in Sec. 141.80(a)(2), the regulations set forth in this
part shall take effect on June 24, 1977.
(b) The regulations for total trihalomethanes set forth in Sec.
141.12(c) shall take effect 2 years after the date of promulgation of
these regulations for community water systems serving 75,000 or more
individuals, and 4 years after the date of promulgation for communities
serving 10,000 to 74,999 individuals.
(c) The regulations set forth in Sec. Sec. 141.11(d); 141.21(a),
(c) and (i); 141.22(a) and (e); 141.23(a)(3) and (a)(4); 141.23(f);
141.24(e) and (f); 141.25(e); 141.27(a); 141.28(a) and (b); 141.31(a),
(d) and (e); 141.32(b)(3); and 141.32(d) shall take effect immediately
upon promulgation.
(d) The regulations set forth in Sec. 141.41 shall take effect 18
months from the date of promulgation. Suppliers
[[Page 437]]
must complete the first round of sampling and reporting within 12 months
following the effective date.
(e) The regulations set forth in Sec. 141.42 shall take effect 18
months from the date of promulgation. All requirements in Sec. 141.42
must be completed within 12 months following the effective date.
(f) The regulations set forth in Sec. 141.11(c) and Sec. 141.23(g)
are effective May 2, 1986. Section 141.23(g)(4) is effective October 2,
1987.
(g) The regulations contained in Sec. 141.6, paragraph (c) of the
table in 141.12, and 141.62(b)(1) are effective July 1, 1991. The
regulations contained in Sec. Sec. 141.11(b), 141.23, 141.24,
142.57(b), 143.4(b)(12) and (b)(13), are effective July 30, 1992. The
regulations contained in the revisions to Sec. Sec. 141.32(e) (16),
(25) through (27) and (46); 141.61(c)(16); and 141.62(b)(3) are
effective January 1, 1993. The effective date of regulations contained
in Sec. 141.61(c) (2), (3), and (4) is postponed.
(h) Regulations for the analytic methods listed at Sec.
141.23(k)(4) for measuring antimony, beryllium, cyanide, nickel, and
thallium are effective August 17, 1992. Regulations for the analytic
methods listed at Sec. 141.24(f)(16) for dichloromethane, 1,2,4-
trichlorobenzene, and 1,1,2-trichloroethane are effective August 17,
1992. Regulations for the analytic methods listed at Sec. 141.24(h)(12)
for measuring dalapon, dinoseb, diquat, endothall, endrin, glyphosate,
oxamyl, picloram, simazine, benzo(a)pyrene, di(2-ethylhexyl)adipate,
di(2-ethylhexyl)phthalate, hexachlorobenzene, hexachlorocyclopentadiene,
and 2,3,7,8-TCDD are effective August 17, 1992. The revision to Sec.
141.12(a) promulgated on July 17, 1992 is effective on August 17, 1992.
(i) [Reserved]
(j) The arsenic maximum contaminant levels (MCL) listed in Sec.
141.62 is effective for the purpose of compliance on January 23, 2006.
Requirements relating to arsenic set forth in Sec. Sec. 141.23(i)(4),
141.23(k)(3) introductory text, 141.23(k)(3)(ii), 141.51(b), 141.62(b),
141.62(b)(16), 141.62(c), 141.62(d), and 142.62(b) revisions in Appendix
A of subpart O for the consumer confidence rule, and Appendices A and B
of subpart Q for the public notification rule are effective for the
purpose of compliance on January 23, 2006. However, the consumer
confidence rule reporting requirements relating to arsenic listed in
Sec. 141.154(b) and (f) are effective for the purpose of compliance on
February 22, 2002.
(k) Regulations set forth in Sec. Sec. 141.23(i)(1), 141.23(i)(2),
141.24(f)(15), 141.24(f)(22), 141.24(h)(11), 141.24(h)(20), 142.16(e),
142.16(j), and 142.16(k) are effective for the purpose of compliance on
January 22, 2004.
[44 FR 68641, Nov. 29, 1979, as amended at 45 FR 57342, Aug. 27, 1980;
47 FR 10998, Mar. 12, 1982; 51 FR 11410, Apr. 2, 1986; 56 FR 30274, July
1, 1991; 57 FR 22178, May 27, 1992; 57 FR 31838, July 17, 1992; 59 FR
34322, July 1, 1994; 61 FR 24368, May 14, 1996; 66 FR 7061, Jan. 22,
2001; 66 FR 28350, May 22, 2001]
Subpart B_Maximum Contaminant Levels
Sec. 141.11 Maximum contaminant levels for inorganic chemicals.
(a) The maximum contaminant level for arsenic applies only to
community water systems. The analyses and determination of compliance
with the 0.05 milligrams per liter maximum contaminant level for arsenic
use the requirements of Sec. 141.23.
(b) The maximum contaminant level for arsenic is 0.05 milligrams per
liter for community water systems until January 23, 2006.
(c) [Reserved]
(d) At the discretion of the State, nitrate levels not to exceed 20
mg/l may be allowed in a non-community water system if the supplier of
water demonstrates to the satisfaction of the State that:
(1) Such water will not be available to children under 6 months of
age; and
(2) The non-community water system is meeting the public
notification requirements under Sec. 141.209, including continuous
posting of the fact that nitrate levels exceed 10 mg/l and the potential
health effects of exposure; and
(3) Local and State public health authorities will be notified
annually of nitrate levels that exceed 10 mg/l; and
[[Page 438]]
(4) No adverse health effects shall result.
[40 FR 59570, Dec. 24, 1975, as amended at 45 FR 57342, Aug. 27, 1980;
47 FR 10998, Mar. 12, 1982; 51 FR 11410, Apr. 2, 1986; 56 FR 3578, Jan.
30, 1991; 56 FR 26548, June 7, 1991; 56 FR 30274, July 1, 1991; 56 FR
32113, July 15, 1991; 60 FR 33932, June 29, 1995; 65 FR 26022, May 4,
2000; 66 FR 7061, Jan. 22, 2001]
Sec. 141.12 [Reserved]
Sec. 141.13 Maximum contaminant levels for turbidity.
The maximum contaminant levels for turbidity are applicable to both
community water systems and non-community water systems using surface
water sources in whole or in part. The maximum contaminant levels for
turbidity in drinking water, measured at a representative entry point(s)
to the distribution system, are:
(a) One turbidity unit (TU), as determined by a monthly average
pursuant to Sec. 141.22, except that five or fewer turbidity units may
be allowed if the supplier of water can demonstrate to the State that
the higher turbidity does not do any of the following:
(1) Interfere with disinfection;
(2) Prevent maintenance of an effective disinfectant agent
throughout the distribution system; or
(3) Interfere with microbiological determinations.
(b) Five turbidity units based on an average for two consecutive
days pursuant to Sec. 141.22.
[40 FR 59570, Dec. 24, 1975]
Editorial Note: At 54 FR 27527, June 29, 1989, Sec. 141.13 was
amended by adding introductory text; however, the amendment could not be
incorporated because introductory text already exists.
Subpart C_Monitoring and Analytical Requirements
Sec. 141.21 Coliform sampling.
(a) Routine monitoring. (1) Public water systems must collect total
coliform samples at sites which are representative of water throughout
the distribution system according to a written sample siting plan. These
plans are subject to State review and revision.
(2) The monitoring frequency for total coliforms for community water
systems is based on the population served by the system, as follows:
Total Coliform Monitoring Frequency for Community Water Systems
------------------------------------------------------------------------
Minimum
number of
Population served samples
per month
------------------------------------------------------------------------
25 to 1,000 \1\.............................................. 1
1,001 to 2,500............................................... 2
2,501 to 3,300............................................... 3
3,301 to 4,100............................................... 4
4,101 to 4,900............................................... 5
4,901 to 5,800............................................... 6
5,801 to 6,700............................................... 7
6,701 to 7,600............................................... 8
7,601 to 8,500............................................... 9
8,501 to 12,900.............................................. 10
12,901 to 17,200............................................. 15
17,201 to 21,500............................................. 20
21,501 to 25,000............................................. 25
25,001 to 33,000............................................. 30
33,001 to 41,000............................................. 40
41,001 to 50,000............................................. 50
50,001 to 59,000............................................. 60
59,001 to 70,000............................................. 70
70,001 to 83,000............................................. 80
83,001 to 96,000............................................. 90
96,001 to 130,000............................................ 100
130,001 to 220,000........................................... 120
220,001 to 320,000........................................... 150
320,001 to 450,000........................................... 180
450,001 to 600,000........................................... 210
600,001 to 780,000........................................... 240
780,001 to 970,000........................................... 270
970,001 to 1,230,000......................................... 300
1,230,001 to 1,520,000....................................... 330
1,520,001 to 1,850,000....................................... 360
1,850,001 to 2,270,000....................................... 390
2,270,001 to 3,020,000....................................... 420
3,020,001 to 3,960,000....................................... 450
3,960,001 or more............................................ 480
------------------------------------------------------------------------
\1\ Includes public water systems which have at least 15 service
connections, but serve fewer than 25 persons.
If a community water system serving 25 to 1,000 persons has no history
of total coliform contamination in its current configuration and a
sanitary survey conducted in the past five years shows that the system
is supplied solely by a protected groundwater source and is free of
sanitary defects, the State may reduce the monitoring frequency
specified above, except that in no case may the State reduce the
monitoring frequency to less than one sample per quarter. The State must
approve the reduced monitoring frequency in writing.
(3) The monitoring frequency for total coliforms for non-community
water systems is as follows:
[[Page 439]]
(i) A non-community water system using only ground water (except
ground water under the direct influence of surface water, as defined in
Sec. 141.2) and serving 1,000 persons or fewer must monitor each
calendar quarter that the system provides water to the public, except
that the State may reduce this monitoring frequency, in writing, if a
sanitary survey shows that the system is free of sanitary defects.
Beginning June 29, 1994, the State cannot reduce the monitoring
frequency for a non-community water system using only ground water
(except ground water under the direct influence of surface water, as
defined in Sec. 141.2) and serving 1,000 persons or fewer to less than
once/year.
(ii) A non-community water system using only ground water (except
ground water under the direct influence of surface water, as defined in
Sec. 141.2) and serving more than 1,000 persons during any month must
monitor at the same frequency as a like-sized community water system, as
specified in paragraph (a)(2) of this section, except the State may
reduce this monitoring frequency, in writing, for any month the system
serves 1,000 persons or fewer. The State cannot reduce the monitoring
frequency to less than once/year. For systems using ground water under
the direct influence of surface water, paragraph (a)(3)(iv) of this
section applies.
(iii) A non-community water system using surface water, in total or
in part, must monitor at the same frequency as a like-sized community
water system, as specified in paragraph (a)(2) of this section,
regardless of the number of persons it serves.
(iv) A non-community water system using ground water under the
direct influence of surface water, as defined in Sec. 141.2, must
monitor at the same frequency as a like-sized community water system, as
specified in paragraph (a)(2) of this section. The system must begin
monitoring at this frequency beginning six months after the State
determines that the ground water is under the direct influence of
surface water.
(4) The public water system must collect samples at regular time
intervals throughout the month, except that a system which uses only
ground water (except ground water under the direct influence of surface
water, as defined in Sec. 141.2), and serves 4,900 persons or fewer,
may collect all required samples on a single day if they are taken from
different sites.
(5) A public water system that uses surface water or ground water
under the direct influence of surface water, as defined in Sec. 141.2,
and does not practice filtration in compliance with Subpart H must
collect at least one sample near the first service connection each day
the turbidity level of the source water, measured as specified in Sec.
141.74(b)(2), exceeds 1 NTU. This sample must be analyzed for the
presence of total coliforms. When one or more turbidity measurements in
any day exceed 1 NTU, the system must collect this coliform sample
within 24 hours of the first exceedance, unless the State determines
that the system, for logistical reasons outside the system's control,
cannot have the sample analyzed within 30 hours of collection. Sample
results from this coliform monitoring must be included in determining
compliance with the MCL for total coliforms in Sec. 141.63.
(6) Special purpose samples, such as those taken to determine
whether disinfection practices are sufficient following pipe placement,
replacement, or repair, shall not be used to determine compliance with
the MCL for total coliforms in Sec. 141.63. Repeat samples taken
pursuant to paragraph (b) of this section are not considered special
purpose samples, and must be used to determine compliance with the MCL
for total coliforms in Sec. 141.63.
(b) Repeat monitoring. (1) If a routine sample is total coliform-
positive, the public water system must collect a set of repeat samples
within 24 hours of being notified of the positive result. A system which
collects more than one routine sample/month must collect no fewer than
three repeat samples for each total coliform-positive sample found. A
system which collects one routine sample/month or fewer must collect no
fewer than four repeat samples for each total coliform-positive sample
found. The State may extend the 24-hour limit on a case-by-case basis if
the system has a logistical
[[Page 440]]
problem in collecting the repeat samples within 24 hours that is beyond
its control. In the case of an extension, the State must specify how
much time the system has to collect the repeat samples.
(2) The system must collect at least one repeat sample from the
sampling tap where the original total coliform-positive sample was
taken, and at least one repeat sample at a tap within five service
connections upstream and at least one repeat sample at a tap within five
service connections downstream of the original sampling site. If a total
coliform-positive sample is at the end of the distribution system, or
one away from the end of the distribution system, the State may waive
the requirement to collect at least one repeat sample upstream or
downstream of the original sampling site.
(3) The system must collect all repeat samples on the same day,
except that the State may allow a system with a single service
connection to collect the required set of repeat samples over a four-day
period or to collect a larger volume repeat sample(s) in one or more
sample containers of any size, as long as the total volume collected is
at least 400 ml (300 ml for systems which collect more than one routine
sample/month).
(4) If one or more repeat samples in the set is total coliform-
positive, the public water system must collect an additional set of
repeat samples in the manner specified in paragraphs (b) (1)-(3) of this
section. The additional samples must be collected within 24 hours of
being notified of the positive result, unless the State extends the
limit as provided in paragraph (b)(1) of this section. The system must
repeat this process until either total coliforms are not detected in one
complete set of repeat samples or the system determines that the MCL for
total coliforms in Sec. 141.63 has been exceeded and notifies the
State.
(5) If a system collecting fewer than five routine samples/month has
one or more total coliform-positive samples and the State does not
invalidate the sample(s) under paragraph (c) of this section, it must
collect at least five routine samples during the next month the system
provides water to the public, except that the State may waive this
requirement if the conditions of paragraph (b)(5) (i) or (ii) of this
section are met. The State cannot waive the requirement for a system to
collect repeat samples in paragraphs (b) (1)-(4) of this section.
(i) The State may waive the requirement to collect five routine
samples the next month the system provides water to the public if the
State, or an agent approved by the State, performs a site visit before
the end of the next month the system provides water to the public.
Although a sanitary survey need not be performed, the site visit must be
sufficiently detailed to allow the State to determine whether additional
monitoring and/or any corrective action is needed. The State cannot
approve an employee of the system to perform this site visit, even if
the employee is an agent approved by the State to perform sanitary
surveys.
(ii) The State may waive the requirement to collect five routine
samples the next month the system provides water to the public if the
State has determined why the sample was total coliform-positive and
establishes that the system has corrected the problem or will correct
the problem before the end of the next month the system serves water to
the public. In this case, the State must document this decision to waive
the following month's additional monitoring requirement in writing, have
it approved and signed by the supervisor of the State official who
recommends such a decision, and make this document available to the EPA
and public. The written documentation must describe the specific cause
of the total coliform-positive sample and what action the system has
taken and/or will take to correct this problem. The State cannot waive
the requirement to collect five routine samples the next month the
system provides water to the public solely on the grounds that all
repeat samples are total coliform-negative. Under this paragraph, a
system must still take at least one routine sample before the end of the
next month it serves water to the public and use it to determine
compliance with the MCL for total coliforms in Sec. 141.63, unless the
State has
[[Page 441]]
determined that the system has corrected the contamination problem
before the system took the set of repeat samples required in paragraphs
(b) (1)-(4) of this section, and all repeat samples were total coliform-
negative.
(6) After a system collects a routine sample and before it learns
the results of the analysis of that sample, if it collects another
routine sample(s) from within five adjacent service connections of the
initial sample, and the initial sample, after analysis, is found to
contain total coliforms, then the system may count the subsequent
sample(s) as a repeat sample instead of as a routine sample.
(7) Results of all routine and repeat samples not invalidated by the
State must be included in determining compliance with the MCL for total
coliforms in Sec. 141.63.
(c) Invalidation of total coliform samples. A total coliform-
positive sample invalidated under this paragraph (c) does not count
towards meeting the minimum monitoring requirements of this section.
(1) The State may invalidate a total coliform-positive sample only
if the conditions of paragraph (c)(1) (i), (ii), or (iii) of this
section are met.
(i) The laboratory establishes that improper sample analysis caused
the total coliform-positive result.
(ii) The State, on the basis of the results of repeat samples
collected as required by paragraphs (b) (1) through (4) of this section,
determines that the total coliform-positive sample resulted from a
domestic or other non-distribution system plumbing problem. The State
cannot invalidate a sample on the basis of repeat sample results unless
all repeat sample(s) collected at the same tap as the original total
coliform-positive sample are also total coliform-positive, and all
repeat samples collected within five service connections of the original
tap are total coliform-negative (e.g., a State cannot invalidate a total
coliform-positive sample on the basis of repeat samples if all the
repeat samples are total coliform-negative, or if the public water
system has only one service connection).
(iii) The State has substantial grounds to believe that a total
coliform-positive result is due to a circumstance or condition which
does not reflect water quality in the distribution system. In this case,
the system must still collect all repeat samples required under
paragraphs (b) (1)-(4) of this section, and use them to determine
compliance with the MCL for total coliforms in Sec. 141.63. To
invalidate a total coliform-positive sample under this paragraph, the
decision with the rationale for the decision must be documented in
writing, and approved and signed by the supervisor of the State official
who recommended the decision. The State must make this document
available to EPA and the public. The written documentation must state
the specific cause of the total coliform-positive sample, and what
action the system has taken, or will take, to correct this problem. The
State may not invalidate a total coliform-positive sample solely on the
grounds that all repeat samples are total coliform-negative.
(2) A laboratory must invalidate a total coliform sample (unless
total coliforms are detected) if the sample produces a turbid culture in
the absence of gas production using an analytical method where gas
formation is examined (e.g., the Multiple-Tube Fermentation Technique),
produces a turbid culture in the absence of an acid reaction in the
Presence-Absence (P-A) Coliform Test, or exhibits confluent growth or
produces colonies too numerous to count with an analytical method using
a membrane filter (e.g., Membrane Filter Technique). If a laboratory
invalidates a sample because of such interference, the system must
collect another sample from the same location as the original sample
within 24 hours of being notified of the interference problem, and have
it analyzed for the presence of total coliforms. The system must
continue to re-sample within 24 hours and have the samples analyzed
until it obtains a valid result. The State may waive the 24-hour time
limit on a case-by-case basis.
(d) Sanitary surveys. (1)(i) Public water systems which do not
collect five or more routine samples/month must undergo an initial
sanitary survey by June 29, 1994, for community public water systems and
June 29, 1999, for
[[Page 442]]
non-community water systems. Thereafter, systems must undergo another
sanitary survey every five years, except that non-community water
systems using only protected and disinfected ground water, as defined by
the State, must undergo subsequent sanitary surveys at least every ten
years after the initial sanitary survey. The State must review the
results of each sanitary survey to determine whether the existing
monitoring frequency is adequate and what additional measures, if any,
the system needs to undertake to improve drinking water quality.
(ii) In conducting a sanitary survey of a system using ground water
in a State having an EPA-approved wellhead protection program under
section 1428 of the Safe Drinking Water Act, information on sources of
contamination within the delineated wellhead protection area that was
collected in the course of developing and implementing the program
should be considered instead of collecting new information, if the
information was collected since the last time the system was subject to
a sanitary survey.
(2) Sanitary surveys must be performed by the State or an agent
approved by the State. The system is responsible for ensuring the survey
takes place.
(3) Sanitary surveys conducted by the State under the provisions of
Sec. 142.16(o)(2) of this chapter may be used to meet the sanitary
survey requirements of this section.
(e) Fecal coliforms/Escherichia coli (E. coli) testing. (1) If any
routine or repeat sample is total coliform-positive, the system must
analyze that total coliform-positive culture medium to determine if
fecal coliforms are present, except that the system may test for E. coli
in lieu of fecal coliforms. If fecal coliforms or E. coli are present,
the system must notify the State by the end of the day when the system
is notified of the test result, unless the system is notified of the
result after the State office is closed, in which case the system must
notify the State before the end of the next business day.
(2) The State has the discretion to allow a public water system, on
a case-by-case basis, to forgo fecal coliform or E. coli testing on a
total coliform-positive sample if that system assumes that the total
coliform-positive sample is fecal coliform-positive or E. coli-positive.
Accordingly, the system must notify the State as specified in paragraph
(e)(1) of this section and the provisions of Sec. 141.63(b) apply.
(f) Analytical methodology. (1) The standard sample volume required
for total coliform analysis, regardless of analytical method used, is
100 ml.
(2) Public water systems need only determine the presence or absence
of total coliforms; a determination of total coliform density is not
required.
(3) Public water systems must conduct total coliform analyses in
accordance with one of the analytical methods in the following table or
one of the alternative methods listed in appendix A to subpart C of this
part.
----------------------------------------------------------------------------------------------------------------
Organism Methodology \12\ Citation \1\
----------------------------------------------------------------------------------------------------------------
Total Coliforms \2\................... Total Coliform Fermentation Technique \3 9221A, B.
4 5\.
Total Coliform Membrane Filter Technique 9222A, B, C.
\6\.
Presence-Absence (P-A) Coliform Test \5 9221D.
7\.
ONPG-MUG Test \8\....................... 9223.
Colisure Test. \9\
E*Colite [supreg] Test. \10\
m-ColiBlue24 [supreg] Test. \11\
Readycult [supreg] Coliforms 100
Presence/Absence Test. \13\
Membrane Filter Technique using
Chromocult [supreg] Coliform Agar. \14\
Colitag [supreg] Test. \15\
----------------------------------------------------------------------------------------------------------------
The procedures shall be done in accordance with the documents listed below. The incorporation by reference of
the following documents listed in footnotes 1, 6, 8, 9, 10 , 11, 13, 14 and 15 was approved by the Director of
the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of the documents may be
obtained from the sources listed below. Information regarding obtaining these documents can be obtained from
the Safe Drinking Water Hotline at 800-426-4791. Documents may be inspected at EPA's Drinking Water Docket,
EPA West, 1301 Constitution Avenue, NW., EPA West, Room B102, Washington DC 20460 (Telephone: 202-566-2426);
or at the National Archives and Records Administration (NARA). For information on the availability of this
material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/
code_of_federal_regulations/ibr_locations.html.
[[Page 443]]
\1\ Standard Methods for the Examination of Water and Wastewater, 18th edition (1992), 19th edition (1995), or
20th edition (1998). American Public Health Association, 1015 Fifteenth Street, NW., Washington, DC 20005. The
cited methods published in any of these three editions may be used. In addition, the following online versions
may also be used: 9221 A, B, D-99, 9222 A, B, C-97, and 9223 B-97. Standard Methods Online are available at
http://www.standardmethods.org. The year in which each method was approved by the Standard Methods Committee
is designated by the last two digits in the method number. The methods listed are the only Online versions
that may be used.
\2\ The time from sample collection to initiation of analysis may not exceed 30 hours. Systems are encouraged
but not required to hold samples below 10 deg. C during transit.
\3\ Lactose broth, as commercially available, may be used in lieu of lauryl tryptose broth, if the system
conducts at least 25 parallel tests between this medium and lauryl tryptose broth using the water normally
tested, and this comparison demonstrates that the false-positive rate and false-negative rate for total
coliform, using lactose broth, is less than 10 percent.
\4\ If inverted tubes are used to detect gas production, the media should cover these tubes at least one-half to
two-thirds after the sample is added.
\5\ No requirement exists to run the completed phase on 10 percent of all total coliform-positive confirmed
tubes.
\6\ MI agar also may be used. Preparation and use of MI agar is set forth in the article, ``New medium for the
simultaneous detection of total coliform and Escherichia coli in water'' by Brenner, K.P., et. al., 1993,
Appl. Environ. Microbiol. 59:3534-3544. Also available from the Office of Water Resource Center (RC-4100T),
1200 Pennsylvania Avenue, NW., Washington, DC 20460, EPA/600/J-99/225. Verification of colonies is not
required.
\7\ Six-times formulation strength may be used if the medium is filter-sterilized rather than autoclaved.
\8\ The ONPG-MUG Test is also known as the Autoanalysis Collect System.
\9\ A description of the Colisure Test, Feb 28, 1994, may be obtained from IDEXX Laboratories, Inc., One IDEXX
Drive, Westbrook, Maine 04092. The Colisure Test may be read after an incubation time of 24 hours.
\10\ A description of the E*Colite [supreg] Test, ``Presence/Absence for Coliforms and E. Coli in Water,'' Dec
21, 1997, is available from Charm Sciences, Inc., 36 Franklin Street, Malden, MA 02148-4120.
\11\ A description of the m-ColiBlue24 [supreg] Test, Aug 17, 1999, is available from the Hach Company, 100
Dayton Avenue, Ames, IA 50010.
\12\ EPA strongly recommends that laboratories evaluate the false-positive and negative rates for the method(s)
they use for monitoring total coliforms. EPA also encourages laboratories to establish false-positive and
false-negative rates within their own laboratory and sample matrix (drinking water or source water) with the
intent that if the method they choose has an unacceptable false-positive or negative rate, another method can
be used. The Agency suggests that laboratories perform these studies on a minimum of 5% of all total coliform-
positive samples, except for those methods where verification/confirmation is already required, e.g., the M-
Endo and LES Endo Membrane Filter Tests, Standard Total Coliform Fermentation Technique, and Presence-Absence
Coliform Test. Methods for establishing false-positive and negative-rates may be based on lactose
fermentation, the rapid test for [beta]-galactosidase and cytochrome oxidase, multi-test identification
systems, or equivalent confirmation tests. False-positive and false-negative information is often available in
published studies and/or from the manufacturer(s).
\13\ The Readycult [supreg] Coliforms 100 Presence/Absence Test is described in the document, ``Readycult
[supreg] Coliforms 100 Presence/Absence Test for Detection and Identification of Coliform Bacteria and
Escherichla coli in Finished Waters'', November 2000, Version 1.0, available from EM Science (an affiliate of
Merck KGgA, Darmstadt Germany), 480 S. Democrat Road, Gibbstown, NJ 08027-1297. Telephone number is (800) 222-
0342, e-mail address is: [email protected].
\14\ Membrane Filter Technique using Chromocult [supreg] Coliform Agar is described in the document,
``Chromocult [supreg] Coliform Agar Presence/Absence Membrane Filter Test Method for Detection and
Identification of Coliform Bacteria and Escherichla coli in Finished Waters'', November 2000, Version 1.0,
available from EM Science (an affiliate of Merck KGgA, Darmstadt Germany), 480 S. Democrat Road, Gibbstown, NJ
08027-1297. Telephone number is (800) 222-0342, e-mail address is: [email protected].
\15\ Colitag [supreg] product for the determination of the presence/absence of total coliforms and E. coli is
described in ``Colitag [supreg] Product as a Test for Detection and Identification of Coliforms and E. coli
Bacteria in Drinking Water and Source Water as Required in National Primary Drinking Water Regulations,''
August 2001, available from CPI International, Inc., 5580 Skylane Blvd., Santa Rosa, CA, 95403, telephone
(800) 878-7654, Fax (707) 545-7901, Internet address http://www.cpiinternational.com.
(4) [Reserved]
(5) Public water systems must conduct fecal coliform analysis in
accordance with the following procedure. When the MTF Technique or
Presence-Absence (PA) Coliform Test is used to test for total coliforms,
shake the lactose-positive presumptive tube or P-A vigorously and
transfer the growth with a sterile 3-mm loop or sterile applicator stick
into brilliant green lactose bile broth and EC medium to determine the
presence of total and fecal coliforms, respectively. For EPA-approved
analytical methods which use a membrane filter, transfer the total
coliform-positive culture by one of the following methods: remove the
membrane containing the total coliform colonies from the substrate with
a sterile forceps and carefully curl and insert the membrane into a tube
of EC medium (the laboratory may first remove a small portion of
selected colonies for verification), swab the entire membrane filter
surface with a sterile cotton swab and transfer the inoculum to EC
medium (do not leave the cotton swab in the EC medium), or inoculate
individual total coliform-positive colonies into EC Medium. Gently shake
the inoculated tubes of EC medium to insure adequate mixing and incubate
in a waterbath at 44.5 0.2 [deg]C for 24 2 hours. Gas production of any amount in the inner
fermentation tube of the EC medium indicates a positive fecal coliform
test. The preparation of EC medium is described in Method 9221E
(paragraph 1a) in Standard Methods for the Examination of Water and
Wastewater, 18th edition (1992), 19th edition (1995), and 20th edition
(1998); the cited method in any one of these three editions may be used.
Public water systems need only determine the presence or absence of
fecal coliforms; a determination of fecal coliform density is not
required.
[[Page 444]]
(6) Public water systems must conduct analysis of Escherichia coli
in accordance with one of the following analytical methods or one of the
alternative methods listed in appendix A to subpart C of this part.
(i) EC medium supplemented with 50 [micro]g/mL of 4-
methylumbelliferyl-beta-D-glucuronide (MUG) (final concentration), as
described in Method 9222G in Standard Methods for the Examination of
Water and Wastewater, 19th edition (1995) and 20th edition (1998).
Either edition may be used. Alternatively, the 18th edition (1992) may
be used if at least 10 mL of EC medium, as described in paragraph (f)(5)
of this section, is supplemented with 50 [micro]g/mL of MUG before
autoclaving. The inner inverted fermentation tube may be omitted. If the
18th edition is used, apply the procedure in paragraph (f)(5) of this
section for transferring a total coliform-positive culture to EC medium
supplemented with MUG, incubate the tube at 44.5 0.2 [deg]C for 24 2 hours, and
then observe fluorescence with an ultraviolet light (366 nm) in the
dark. If fluorescence is visible, E. coli are present.
(ii) Nutrient agar supplemented with 100 [micro]g/mL of 4-
methylumbelliferyl-beta-D-glucuronide (MUG) (final concentration), as
described in Method 9222G in Standard Methods for the Examination of
Water and Wastewater, 19th edition (1995) and 20th edition (1998).
Either edition may be used for determining if a total coliform-positive
sample, as determined by a membrane filter technique, contains E. coli.
Alternatively, the 18th edition (1992) may be used if the membrane
filter containing a total coliform-positive colony(ies) is transferred
to nutrient agar, as described in Method 9221B (paragraph 3) of Standard
Methods (18th edition), supplemented with 100 [micro]g/mL of MUG. If the
18th edition is used, incubate the agar plate at 35 [deg]C for 4 hours
and then observe the colony(ies) under ultraviolet light (366 nm) in the
dark for fluorescence. If fluorescence is visible, E. coli are present.
(iii) Minimal Medium ONPG-MUG (MMO-MUG) Test, as set forth in the
article ``National Field Evaluation of a Defined Substrate Method for
the Simultaneous Detection of Total Coliforms and Escherichia coli from
Drinking Water: Comparison with Presence-Absence Techniques'' (Edberg et
al.), Applied and Environmental Microbiology, Volume 55, pp. 1003-1008,
April 1989. (Note: The Autoanalysis Colilert System is an MMO-MUG test).
If the MMO-MUG test is total coliform-positive after a 24-hour
incubation, test the medium for fluorescence with a 366-nm ultraviolet
light (preferably with a 6-watt lamp) in the dark. If fluorescence is
observed, the sample is E. coli-positive. If fluorescence is
questionable (cannot be definitively read) after 24 hours incubation,
incubate the culture for an additional four hours (but not to exceed 28
hours total), and again test the medium for fluorescence. The MMO-MUG
Test with hepes buffer in lieu of phosphate buffer is the only approved
formulation for the detection of E. coli.
(iv) The Colisure Test. A description of the Colisure Test may be
obtained from the Millipore Corporation, Technical Services Department,
80 Ashby Road, Bedford, MA 01730.
(v) The membrane filter method with MI agar, a description of which
is cited in footnote 6 to the table in paragraph (f)(3) of this section.
(vi) E*Colite [supreg] Test, a description of which is cited in
footnote 10 to the table at paragraph (f)(3) of this section.
(vii) m-ColiBlue24 [supreg] Test, a description of which is cited in
footnote 11 to the table in paragraph (f)(3) of this section.
(viii) Readycult [supreg] Coliforms 100 Presence/Absence Test, a
description of which is cited in footnote 13 to the table at paragraph
(f)(3) of this section.
(ix) Membrane Filter Technique using Chromocult [supreg] Coliform
Agar, a description of which is cited in footnote 14 to the table at
paragraph (f)(3) of this section.
(x) Colitag [supreg], a description of which is cited in footnote 15
to the table at paragraph (f)(3) of this section.
(7) As an option to paragraph (f)(6)(iii) of this section, a system
with a total coliform-positive, MUG-negative, MMO-MUG test may further
analyze the culture for the presence of E. coli by transferring a 0.1
ml, 28-hour MMO-MUG culture to EC Medium + MUG with a pipet. The
formulation and incubation conditions of EC Medium +
[[Page 445]]
MUG, and observation of the results are described in paragraph (f)(6)(i)
of this section.
(8) The following materials are incorporated by reference in this
section with the approval of the Director of the Federal Register in
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of the
analytical methods cited in Standard Methods for the Examination of
Water and Wastewater (18th, 19th, and 20th editions) may be obtained
from the American Public Health Association et al.; 1015 Fifteenth
Street, NW., Washington, DC 20005-2605. Copies of the MMO-MUG Test, as
set forth in the article ``National Field Evaluation of a Defined
Substrate Method for the Simultaneous Enumeration of Total Coliforms and
Escherichia coli from Drinking Water: Comparison with the Standard
Multiple Tube Fermentation Method'' (Edberg et al.) may be obtained from
the American Water Works Association Research Foundation, 6666 West
Quincy Avenue, Denver, CO 80235. Copies of the MMO-MUG Test as set forth
in the article ``National Field Evaluation of a Defined Substrate Method
for the Simultaneous Enumeration of Total Coliforms and Escherichia coli
from Drinking Water: Comparison with the Standard Multiple Tube
Fermentation Method'' (Edberg et al.) may be obtained from the American
Water Works Association Research Foundation, 6666 West Quincy Avenue,
Denver, CO 80235. A description of the Colisure Test may be obtained
from the Millipore Corp., Technical Services Department, 80 Ashby Road,
Bedford, MA 01730. Copies may be inspected at EPA's Drinking Water
Docket; 401 M St., SW.; Washington, DC 20460, or at the National
Archives and Records Administration (NARA). For information on the
availability of this material at NARA, call 202-741-6030, or go to:
http://www.archives.gov/federal_register/code_of_federal_regulations/
ibr_locations.html.
(g) Response to violation. (1) A public water system which has
exceeded the MCL for total coliforms in Sec. 141.63 must report the
violation to the State no later than the end of the next business day
after it learns of the violation, and notify the public in accordance
with subpart Q.
(2) A public water system which has failed to comply with a coliform
monitoring requirement, including the sanitary survey requirement, must
report the monitoring violation to the State within ten days after the
system discovers the violation, and notify the public in accordance with
subpart Q.
(h) The provisions of paragraphs (a) and (d) of this section are
applicable until March 31, 2016. The provisions of paragraphs (b), (c),
(e), (f), and (g) of this section are applicable until all required
repeat monitoring under paragraph (b) of this section and fecal coliform
or E. coli testing under paragraph (e) of this section that was
initiated by a total coliform-positive sample taken before April 1, 2016
is completed, as well as analytical method, reporting, recordkeeping,
public notification, and consumer confidence report requirements
associated with that monitoring and testing. Beginning April 1, 2016,
the provisions of subpart Y of this part are applicable, with systems
required to begin regular monitoring at the same frequency as the
system-specific frequency required on March 31, 2016.
[54 FR 27562, June 29, 1989]
Editorial Note: For Federal Register citations affecting Sec.
141.21, see the List of CFR Sections Affected, which appears in the
Finding Aids section of the printed volume and at www.fdsys.gov.
Sec. 141.22 Turbidity sampling and analytical requirements.
The requirements in this section apply to unfiltered systems until
December 30, 1991, unless the State has determined prior to that date,
in writing pursuant to section 1412(b)(7)(iii), that filtration is
required. The requirements in this section apply to filtered systems
until June 29, 1993. The requirements in this section apply to
unfiltered systems that the State has determined, in writing pursuant to
section 1412(b)(7)(C)(iii), must install filtration, until June 29,
1993, or until filtration is installed, whichever is later.
(a) Samples shall be taken by suppliers of water for both community
and non-community water systems at a representative entry point(s) to
the water distribution system at least once
[[Page 446]]
per day, for the purposes of making turbidity measurements to determine
compliance with Sec. 141.13. If the State determines that a reduced
sampling frequency in a non-community will not pose a risk to public
health, it can reduce the required sampling frequency. The option of
reducing the turbidity frequency shall be permitted only in those public
water systems that practice disinfection and which maintain an active
residual disinfectant in the distribution system, and in those cases
where the State has indicated in writing that no unreasonable risk to
health existed under the circumstances of this option. Turbidity
measurements shall be made as directed in Sec. 141.74(a)(1).
(b) If the result of a turbidity analysis indicates that the maximum
allowable limit has been exceeded, the sampling and measurement shall be
confirmed by resampling as soon as practicable and preferably within one
hour. If the repeat sample confirms that the maximum allowable limit has
been exceeded, the supplier of water shall report to the State within 48
hours. The repeat sample shall be the sample used for the purpose of
calculating the monthly average. If the monthly average of the daily
samples exceeds the maximum allowable limit, or if the average of two
samples taken on consecutive days exceeds 5 TU, the supplier of water
shall report to the State and notify the public as directed in Sec.
141.31 and subpart Q.
(c) Sampling for non-community water systems shall begin within two
years after the effective date of this part.
(d) The requirements of this Sec. 141.22 shall apply only to public
water systems which use water obtained in whole or in part from surface
sources.
(e) The State has the authority to determine compliance or initiate
enforcement action based upon analytical results or other information
compiled by their sanctioned representatives and agencies.
[40 FR 59570, Dec. 24, 1975, as amended at 45 FR 57344, Aug. 27, 1980;
47 FR 8998, Mar. 3, 1982; 47 FR 10998, Mar. 12, 1982; 54 FR 27527, June
29, 1989; 59 FR 62466, Dec. 5, 1994; 65 FR 26022, May 4, 2000]
Sec. 141.23 Inorganic chemical sampling and analytical requirements.
Community water systems shall conduct monitoring to determine
compliance with the maximum contaminant levels specified in Sec. 141.62
in accordance with this section. Non-transient, non-community water
systems shall conduct monitoring to determine compliance with the
maximum contaminant levels specified in Sec. 141.62 in accordance with
this section. Transient, non-community water systems shall conduct
monitoring to determine compliance with the nitrate and nitrite maximum
contaminant levels in Sec. Sec. 141.11 and 141.62 (as appropriate) in
accordance with this section.
(a) Monitoring shall be conducted as follows:
(1) Groundwater systems shall take a minimum of one sample at every
entry point to the distribution system which is representative of each
well after treatment (hereafter called a sampling point) beginning in
the initial compliance period. The system shall take each sample at the
same sampling point unless conditions make another sampling point more
representative of each source or treatment plant.
(2) Surface water systems shall take a minimum of one sample at
every entry point to the distribution system after any application of
treatment or in the distribution system at a point which is
representative of each source after treatment (hereafter called a
sampling point) beginning in the initial compliance period. The system
shall take each sample at the same sampling point unless conditions make
another sampling point more representative of each source or treatment
plant.
Note: For purposes of this paragraph, surface water systems include
systems with a combination of surface and ground sources.
(3) If a system draws water from more than one source and the
sources are combined before distribution, the system must sample at an
entry point to the distribution system during periods of normal
operating conditions (i.e., when water is representative of all sources
being used).
[[Page 447]]
(4) The State may reduce the total number of samples which must be
analyzed by allowing the use of compositing. Composite samples from a
maximum of five samples are allowed, provided that the detection limit
of the method used for analysis is less than one-fifth of the MCL.
Compositing of samples must be done in the laboratory.
(i) If the concentration in the composite sample is greater than or
equal to one-fifth of the MCL of any inorganic chemical, then a follow-
up sample must be taken within 14 days at each sampling point included
in the composite. These samples must be analyzed for the contaminants
which exceeded one-fifth of the MCL in the composite sample. Detection
limits for each analytical method and MCLs for each inorganic
contaminant are the following:
Detection Limits for Inorganic Contaminants
------------------------------------------------------------------------
Detection
Contaminant MCL (mg/l) Methodology limit (mg/l)
------------------------------------------------------------------------
Antimony.................. 0.006...... Atomic 0.003
Absorption;
Furnace.
Atomic 0.0008 \5\
Absorption;
Platform.
ICP-Mass 0.0004
Spectrometry.
Hydride-Atomic 0.001
Absorption.
Arsenic................... 0.010 \6\.. Atomic 0.001
Absorption;
Furnace.
Atomic 0.0005 \7\
Absorption;
Platform--Stabi
lized
Temperature.
Atomic 0.001
Absorption;
Gaseous Hydride.
ICP-Mass 0.0014 \8\
Spectrometry.
Asbestos.................. 7 MFL \1\.. Transmission 0.01 MFL
Electron
Microscopy.
Barium.................... 2.......... Atomic 0.002
Absorption;
furnace
technique.
Atomic 0.1
Absorption;
direct
aspiration.
Inductively 0.002 (0.001)
Coupled Plasma.
Beryllium................. 0.004...... Atomic 0.0002
Absorption;
Furnace.
Atomic 0.00002 \5\
Absorption;
Platform.
Inductively 0.0003
Coupled Plasma
\2\.
ICP-Mass 0.0003
Spectrometry.
Cadmium................... 0.005...... Atomic 0.0001
Absorption;
furnace
technique.
Inductively 0.001
Coupled Plasma.
Chromium.................. 0.1........ Atomic 0.001
Absorption;
furnace
technique.
Inductively 0.007 (0.001)
Coupled Plasma.
Cyanide................... 0.2........ Distillation, 0.02
Spectrophotomet
ric \3\.
........... Distillation, 0.005
Automated,
Spectrophotomet
ric \3\.
........... Distillation, 0.02
Amenable,
Spectrophotomet
ric \4\.
........... Distillation, 0.05
Selective
Electrode\3 4\.
........... UV, 0.0005
Distillation,
Spectrophotomet
ric \9\.
........... Micro 0.0006
Distillation,
Flow Injection,
Spectrophotomet
ric \3\.
........... Ligand Exchange 0.0005
with
Amperometry \4\.
Mercury................... 0.002...... Manual Cold 0.0002
Vapor Technique.
Automated Cold 0.0002
Vapor Technique.
Nickel.................... xl......... Atomic 0.001
Absorption;
Furnace.
Atomic 0.0006 \5\
Absorption;
Platform.
Inductively 0.005
Coupled Plasma
\2\.
ICP-Mass 0.0005
Spectrometry.
Nitrate................... 10 (as N).. Manual Cadmium 0.01
Reduction.
Automated 0.01
Hydrazine
Reduction.
Automated 0.05
Cadmium
Reduction.
Ion Selective 1
Electrode.
Ion 0.01
Chromatography.
Capillary Ion 0.076
Electrophoresis.
Nitrite................... 1 (as N)... Spectrophotometr 0.01
ic.
Automated 0.05
Cadmium
Reduction.
Manual Cadmium 0.01
Reduction.
Ion 0.004
Chromatography.
Capillary Ion 0.103
Electrophoresis.
Selenium.................. 0.05....... Atomic 0.002
Absorption;
furnace.
Atomic 0.002
Absorption;
gaseous hydride.
Thallium.................. 0.002...... Atomic 0.001
Absorption;
Furnace.
Atomic 0.0007 \5\
Absorption;
Platform.
ICP-Mass 0.0003
Spectrometry.
------------------------------------------------------------------------
\1\ MFL = million fibers per liter 10 [micro]m.
\2\ Using a 2X preconcentration step as noted in Method 200.7. Lower
MDLs may be achieved when using a 4X preconcentration.
\3\ Screening method for total cyanides.
\4\ Measures ``free'' cyanides when distillation, digestion, or ligand
exchange is omitted.
\5\ Lower MDLs are reported using stabilized temperature graphite
furnace atomic absorption.
[[Page 448]]
\6\ The value for arsenic is effective January 23, 2006. Unit then, the
MCL is 0.05 mg/L.
\7\ The MDL reported for EPA method 200.9 (Atomic Absorption; Platform--
Stablized Temperature) was determined using a 2x concentration step
during sample digestion. The MDL determined for samples analyzed using
direct analyses (i.e., no sample digestion) will be higher. Using
multiple depositions, EPA 200.9 is capable of obtaining MDL of 0.0001
mg/L.
\8\ Using selective ion monitoring, EPA Method 200.8 (ICP-MS) is capable
of obtaining a MDL of 0.0001 mg/L.
\9\ Measures total cyanides when UV-digestor is used, and ``free''
cyanides when UV-digestor is bypassed.
(ii) If the population served by the system is 3,300
persons, then compositing may only be permitted by the State at sampling
points within a single system. In systems serving <=3,300 persons, the
State may permit compositing among different systems provided the 5-
sample limit is maintained.
(iii) If duplicates of the original sample taken from each sampling
point used in the composite sample are available, the system may use
these instead of resampling. The duplicates must be analyzed and the
results reported to the State within 14 days after completing analysis
of the composite sample, provided the holding time of the sample is not
exceeded.
(5) The frequency of monitoring for asbestos shall be in accordance
with paragraph (b) of this section: the frequency of monitoring for
antimony, arsenic, barium, beryllium, cadmium, chromium, cyanide,
fluoride, mercury, nickel, selenium and thallium shall be in accordance
with paragraph (c) of this section; the frequency of monitoring for
nitrate shall be in accordance with paragraph (d) of this section; and
the frequency of monitoring for nitrite shall be in accordance with
paragraph (e) of this section.
(b) The frequency of monitoring conducted to determine compliance
with the maximum contaminant level for asbestos specified in Sec.
141.62(b) shall be conducted as follows:
(1) Each community and non-transient, non-community water system is
required to monitor for asbestos during the first three-year compliance
period of each nine-year compliance cycle beginning in the compliance
period starting January 1, 1993.
(2) If the system believes it is not vulnerable to either asbestos
contamination in its source water or due to corrosion of asbestos-cement
pipe, or both, it may apply to the State for a waiver of the monitoring
requirement in paragraph (b)(1) of this section. If the State grants the
waiver, the system is not required to monitor.
(3) The State may grant a waiver based on a consideration of the
following factors:
(i) Potential asbestos contamination of the water source, and
(ii) The use of asbestos-cement pipe for finished water distribution
and the corrosive nature of the water.
(4) A waiver remains in effect until the completion of the three-
year compliance period. Systems not receiving a waiver must monitor in
accordance with the provisions of paragraph (b)(1) of this section.
(5) A system vulnerable to asbestos contamination due solely to
corrosion of asbestos-cement pipe shall take one sample at a tap served
by asbestos-cement pipe and under conditions where asbestos
contamination is most likely to occur.
(6) A system vulnerable to asbestos contamination due solely to
source water shall monitor in accordance with the provision of paragraph
(a) of this section.
(7) A system vulnerable to asbestos contamination due both to its
source water supply and corrosion of asbestos-cement pipe shall take one
sample at a tap served by asbestos-cement pipe and under conditions
where asbestos contamination is most likely to occur.
(8) A system which exceeds the maximum contaminant levels as
determined in Sec. 141.23(i) of this section shall monitor quarterly
beginning in the next quarter after the violation occurred.
(9) The State may decrease the quarterly monitoring requirement to
the frequency specified in paragraph (b)(1) of this section provided the
State has determined that the system is reliably and consistently below
the maximum contaminant level. In no case can a State make this
determination unless a groundwater system takes a minimum of two
quarterly samples and a surface (or combined surface/ground)
[[Page 449]]
water system takes a minimum of four quarterly samples.
(10) If monitoring data collected after January 1, 1990 are
generally consistent with the requirements of Sec. 141.23(b), then the
State may allow systems to use that data to satisfy the monitoring
requirement for the initial compliance period beginning January 1, 1993.
(c) The frequency of monitoring conducted to determine compliance
with the maximum contaminant levels in Sec. 141.62 for antimony,
arsenic, barium, beryllium, cadmium, chromium, cyanide, fluoride,
mercury, nickel, selenium and thallium shall be as follows:
(1) Groundwater systems shall take one sample at each sampling point
during each compliance period. Surface water systems (or combined
surface/ground) shall take one sample annually at each sampling point.
(2) The system may apply to the State for a waiver from the
monitoring frequencies specified in paragraph (c)(1) of this section.
States may grant a public water system a waiver for monitoring of
cyanide, provided that the State determines that the system is not
vulnerable due to lack of any industrial source of cyanide.
(3) A condition of the waiver shall require that a system shall take
a minimum of one sample while the waiver is effective. The term during
which the waiver is effective shall not exceed one compliance cycle
(i.e., nine years).
(4) The State may grant a waiver provided surface water systems have
monitored annually for at least three years and groundwater systems have
conducted a minimum of three rounds of monitoring. (At least one sample
shall have been taken since January 1, 1990). Both surface and
groundwater systems shall demonstrate that all previous analytical
results were less than the maximum contaminant level. Systems that use a
new water source are not eligible for a waiver until three rounds of
monitoring from the new source have been completed.
(5) In determining the appropriate reduced monitoring frequency, the
State shall consider:
(i) Reported concentrations from all previous monitoring;
(ii) The degree of variation in reported concentrations; and
(iii) Other factors which may affect contaminant concentrations such
as changes in groundwater pumping rates, changes in the system's
configuration, changes in the system's operating procedures, or changes
in stream flows or characteristics.
(6) A decision by the State to grant a waiver shall be made in
writing and shall set forth the basis for the determination. The
determination may be initiated by the State or upon an application by
the public water system. The public water system shall specify the basis
for its request. The State shall review and, where appropriate, revise
its determination of the appropriate monitoring frequency when the
system submits new monitoring data or when other data relevant to the
system's appropriate monitoring frequency become available.
(7) Systems which exceed the maximum contaminant levels as
calculated in Sec. 141.23(i) of this section shall monitor quarterly
beginning in the next quarter after the violation occurred.
(8) The State may decrease the quarterly monitoring requirement to
the frequencies specified in paragraphs (c)(1) and (c)(2) of this
section provided it has determined that the system is reliably and
consistently below the maximum contaminant level. In no case can a State
make this determination unless a groundwater system takes a minimum of
two quarterly samples and a surface water system takes a minimum of four
quarterly samples.
(9) All new systems or systems that use a new source of water that
begin operation after January 22, 2004 must demonstrate compliance with
the MCL within a period of time specified by the State. The system must
also comply with the initial sampling frequencies specified by the State
to ensure a system can demonstrate compliance with the MCL. Routine and
increased monitoring frequencies shall be conducted in accordance with
the requirements in this section.
(d) All public water systems (community; non-transient, non-
community;
[[Page 450]]
and transient, non-community systems) shall monitor to determine
compliance with the maximum contaminant level for nitrate in Sec.
141.62.
(1) Community and non-transient, non-community water systems served
by groundwater systems shall monitor annually beginning January 1, 1993;
systems served by surface water shall monitor quarterly beginning
January 1, 1993.
(2) For community and non-transient, non-community water systems,
the repeat monitoring frequency for groundwater systems shall be
quarterly for at least one year following any one sample in which the
concentration is =50 percent of the MCL. The State may allow
a groundwater system to reduce the sampling frequency to annually after
four consecutive quarterly samples are reliably and consistently less
than the MCL.
(3) For community and non-transient, non-community water systems,
the State may allow a surface water system to reduce the sampling
frequency to annually if all analytical results from four consecutive
quarters are <50 percent of the MCL. A surface water system shall return
to quarterly monitoring if any one sample is =50 percent of
the MCL.
(4) Each transient non-community water system shall monitor annually
beginning January 1, 1993.
(5) After the initial round of quarterly sampling is completed, each
community and non-transient non-community system which is monitoring
annually shall take subsequent samples during the quarter(s) which
previously resulted in the highest analytical result.
(e) All public water systems (community; non-transient, non-
community; and transient, non-community systems) shall monitor to
determine compliance with the maximum contaminant level for nitrite in
Sec. 141.62(b).
(1) All public water systems shall take one sample at each sampling
point in the compliance period beginning January 1, 1993 and ending
December 31, 1995.
(2) After the initial sample, systems where an analytical result for
nitrite is <50 percent of the MCL shall monitor at the frequency
specified by the State.
(3) For community, non-transient, non-community, and transient non-
community water systems, the repeat monitoring frequency for any water
system shall be quarterly for at least one year following any one sample
in which the concentration is =50 percent of the MCL. The
State may allow a system to reduce the sampling frequency to annually
after determining the system is reliably and consistently less than the
MCL.
(4) Systems which are monitoring annually shall take each subsequent
sample during the quarter(s) which previously resulted in the highest
analytical result.
(f) Confirmation samples:
(1) Where the results of sampling for antimony, arsenic, asbestos,
barium, beryllium, cadmium, chromium, cyanide, fluoride, mercury,
nickel, selenium or thallium indicate an exceedance of the maximum
contaminant level, the State may require that one additional sample be
collected as soon as possible after the initial sample was taken (but
not to exceed two weeks) at the same sampling point.
(2) Where nitrate or nitrite sampling results indicate an exceedance
of the maximum contaminant level, the system shall take a confirmation
sample within 24 hours of the system's receipt of notification of the
analytical results of the first sample. Systems unable to comply with
the 24-hour sampling requirement must immediately notify persons served
by the public water system in accordance with Sec. 141.202 and meet
other Tier 1 public notification requirements under subpart Q of this
part. Systems exercising this option must take and analyze a
confirmation sample within two weeks of notification of the analytical
results of the first sample.
(3) If a State-required confirmation sample is taken for any
contaminant, then the results of the initial and confirmation sample
shall be averaged. The resulting average shall be used to determine the
system's compliance in accordance with paragraph (i) of this section.
States have the discretion to delete results of obvious sampling errors.
(g) The State may require more frequent monitoring than specified in
[[Page 451]]
paragraphs (b), (c), (d) and (e) of this section or may require
confirmation samples for positive and negative results at its
discretion.
(h) Systems may apply to the State to conduct more frequent
monitoring than the minimum monitoring frequencies specified in this
section.
(i) Compliance with Sec. 141.11 or Sec. 141.62(b) (as appropriate)
shall be determined based on the analytical result(s) obtained at each
sampling point.
(1) For systems which are conducting monitoring at a frequency
greater than annual, compliance with the maximum contaminant levels for
antimony, arsenic, asbestos, barium, beryllium, cadmium, chromium,
cyanide, fluoride, mercury, nickel, selenium or thallium is determined
by a running annual average at any sampling point. If the average at any
sampling point is greater than the MCL, then the system is out of
compliance. If any one sample would cause the annual average to be
exceeded, then the system is out of compliance immediately. Any sample
below the method detection limit shall be calculated at zero for the
purpose of determining the annual average. If a system fails to collect
the required number of samples, compliance (average concentration) will
be based on the total number of samples collected.
(2) For systems which are monitoring annually, or less frequently,
the system is out of compliance with the maximum contaminant levels for
antimony, arsenic, asbestos, barium, beryllium, cadmium, chromium,
cyanide, fluoride, mercury, nickel, selenium or thallium if the level of
a contaminant is greater than the MCL. If confirmation samples are
required by the State, the determination of compliance will be based on
the annual average of the initial MCL exceedance and any State-required
confirmation samples. If a system fails to collect the required number
of samples, compliance (average concentration) will be based on the
total number of samples collected.
(3) Compliance with the maximum contaminant levels for nitrate and
nitrate is determined based on one sample if the levels of these
contaminants are below the MCLs. If the levels of nitrate and/or nitrite
exceed the MCLs in the initial sample, a confirmation sample is required
in accordance with paragraph (f)(2) of this section, and compliance
shall be determined based on the average of the initial and confirmation
samples.
(4) Arsenic sampling results will be reported to the nearest 0.001
mg/L.
(j) Each public water system shall monitor at the time designated by
the State during each compliance period.
(k) Inorganic analysis:
(1) Analysis for the following contaminants shall be conducted in
accordance with the methods in the following table, or the alternative
methods listed in appendix A to subpart C of this part, or their
equivalent as determined by EPA. Criteria for analyzing arsenic, barium,
beryllium, cadmium, calcium, chromium, copper, lead, nickel, selenium,
sodium, and thallium with digestion or directly without digestion, and
other analytical test procedures are contained in Technical Notes on
Drinking Water Methods, EPA-600/R-94-173, October 1994. This document is
available from the National Service Center for Environmental
Publications (NSCEP), P.O. Box 42419, Cincinnati, OH 45242-0419 or
http://www.epa.gov/nscep/.
[[Page 452]]
--------------------------------------------------------------------------------------------------------------------------------------------------------
SM \4\ (18th, SM \4\ (20th
Contaminant Methodology \13\ EPA ASTM \3\ 19th ed.) ed.) SM Online \22\ Other
--------------------------------------------------------------------------------------------------------------------------------------------------------
1. Alkalinity................ Titrimetric..... ................ D1067-92, 02 B.. 2320 B.......... 2320 B......... 2320 B-97......
Electrometric ................ ................ ................ ............... I-1030-85 \5\..
titration.
2. Antimony.................. Inductively 200.8 \2\
Coupled Plasma
(ICP)--Mass
Spectrometry.
Hydride-Atomic ................ D3697-92, 02....
Absorption.
Atomic 200.9 \2\
Absorption;
Platform.
Atomic ................ ................ 3113 B.......... ............... 3113 B-99......
Absorption;
Furnace.
3. Arsenic \14\.............. ICP-Mass 200.8 \2\.......
Spectrometry.
Atomic 200.9 \2\.......
Absorption;
Platform.
Atomic ................ D2972-97, 03 C.. 3113 B.......... ............... 3113 B-99......
Absorption;
Furnace.
Hydride Atomic ................ D1972-97, 03 B.. 3114 B.......... ............... 3114 B-97......
Absorption.
4. Asbestos.................. Transmission 100.1 \9\
Electron
Microscopy.
Transmission 100.2 \10\
Electron
Microscopy.
5. Barium.................... Inductively 200.7 \2\....... ................ 3120 B.......... 3120 B......... 3120 B-99......
Coupled Plasma.
ICP-Mass 200.8 \2\
Spectrometry.
Atomic ................ ................ 3111D........... ............... 3111 D-99......
Absorption;
Direct.
Atomic ................ ................ 3113 B.......... ............... 3113 B-99......
Absorption;
Furnace.
6. Beryllium................. Inductively 200.7 \2\....... ................ 3120 B.......... 3120 B......... 3120 B-99......
Coupled Plasma.
ICP-Mass 200.8 \2\
Spectrometry.
Atomic 200.9 \2\
Absorption;
Platform.
Atomic ................ D3645-97, 03 B.. 3113 B.......... ............... 3113 B-99......
Absorption;
Furnace.
7. Cadmium................... Inductively 200.7 \2\
Coupled Plasma.
ICP-Mass 200.8 \2\
Spectrometry.
Atomic 200.9 \2\
Absorption;
Platform.
[[Page 453]]
Atomic ................ ................ 3113 B.......... ............... 3113 B-99......
Absorption;
Furnace.
8. Calcium................... EDTA titrimetric ................ D511-93, 03 A... 3500-Ca D....... 3500-Ca B...... 3500-Ca B-97...
Atomic ................ D511-93, 03 B... 3111 B.......... ............... 3111 B-99......
Absorption;
Direct
Aspiration.
Inductively 200.7 \2\....... ................ 3120 B.......... 3120 B......... 3120 B-99......
Coupled Plasma.
Ion ................ D6919-03........
Chromatography.
9. Chromium.................. Inductively 200.7 \2\....... ................ 3120 B.......... 3120 B......... 3120 B-99......
Coupled Plasma.
ICP-Mass 200.8 \2\
Spectrometry.
Atomic 200.9 \2\
Absorption;
Platform.
Atomic ................ ................ 3113 B.......... ............... 3113 B-99......
Absorption;
Furnace.
10. Copper................... Atomic ................ D1688-95, 02 C.. 3113 B.......... ............... 3113 B-99......
Absorption;
Furnace.
Atomic ................ D1688-95, 02 A.. 3111 B.......... ............... 3111 B-99......
Absorption;
Direct
Aspiration.
Inductively 200.7 \2\....... ................ 3120 B.......... 3120 B......... 3120 B-99......
Coupled Plasma.
ICP-Mass 200.8 \2\
spectrometry.
Atomic 200.9 \2\
Absorption;
Platform.
11. Conductivity............. Conductance..... ................ D1125-95 2510 B.......... 2510 B......... 2510 B-97......
(Reapproved
1999) A.
12. Cyanide.................. Manual ................ D2036-98 A...... 4500-CN- C...... 4500-CN- C.....
Distillation
followed by
Spectrophotom ................ D2036-98 B...... 4500-CN- G...... 4500-CN- G..... 4500-CN- G-99..
etric,
Amenable.
Spectro- ................ D2036-98 A...... 4500-CN- E...... 4500-CN- E..... 4500-CN- E-99.. I-3300-85 \5\
photometric
Manual.
Spectro- 335.4 \6\
photometric
Semi-
automated.
Selective ................ ................ 4500-CN- F...... 4500-CN- F..... 4500-CN- F-99..
Electrode.
UV, ................ ................ ................ ............... ............... Kelada-01 \17\
Distillation,
Spectrophotomet
ric.
Micro ................ ................ ................ ............... ............... QuikChem 10-204-
Distillation, 00-1-X \18\
Flow Injection,
Spectrophotomet
ric.
Ligand Exchange ................ D6888-04........ ................ ............... ............... OIA-1677, DW
and Amperometry \20\
\21\.
[[Page 454]]
13. Fluoride................. Ion 300.0 \6\, 300.1 D4327-97, 03.... 4110 B.......... 4110 B......... 4110 B-00......
Chromatography. \19\
Manual Distill.; ................ ................ 4500-F- B, D.... 4500-F- B, D... 4500-F- B, D-97
Color. SPADNS.
Manual Electrode ................ D1179-93, 99 B.. 4500-F- C....... 4500-F- C...... 4500-F- C-97...
Automated ................ ................ ................ ............... ............... 380-75WE \11\
Electrode.
Automated ................ ................ 4500-F- E....... 4500-F- E...... 4500-F- E-97... 129-71W \11\
Alizarin.
Capillary Ion ................ ................ ................ ............... ............... D6508, Rev. 2
Electrophoresis. \23\
14. Lead..................... Atomic ................ D3559-96, 03 D.. 3113 B.......... ............... 3113 B-99......
Absorption;
Furnace.
ICP-Mass 200.8 \2\
spectrometry.
Atomic 200.9 \2\
Absorption;
Platform.
Differential ................ ................ ................ ............... ............... Method 1001
Pulse Anodic \16\
Stripping
Voltametry.
15. Magnesium................ Atomic ................ D511-93, 03 B... 3111 B.......... ............... 3111 B-99......
Absorption.
ICP............. 200.7 \2\....... ................ 3120 B.......... 3120 B......... 3120 B-99......
Complexation ................ D511-93, 03 A... 3500-Mg E....... 3500-Mg B...... 3500-Mg B-97...
Titrimetric
Methods.
Ion ................ D6919-03........
Chromatography.
16. Mercury.................. Manual, Cold 245.1 \2\....... D3223-97, 02.... 3112 B.......... ............... 3112 B-99......
Vapor.
Automated, Cold 245.2 \1\
Vapor.
ICP-Mass 200.8 \2\
Spectrometry.
17. Nickel................... Inductively 200.7 \2\....... ................ 3120 B.......... 3120 B......... 3120 B-99......
Coupled Plasma.
ICP-Mass 200.8 \2\
Spectrometry.
Atomic 200.9 \2\
Absorption;
Platform.
Atomic ................ ................ 3111 B.......... ............... 3111 B-99......
Absorption;
Direct.
Atomic ................ ................ 3113 B.......... ............... 3113 B-99......
Absorption;
Furnace.
18. Nitrate.................. Ion 300.0 \6\, 300.1 D4327-97, 03.... 4110 B.......... 4110 B......... 4110 B-00...... B-1011 \8\
Chromatography. \19\
Automated 353.2 \6\....... D3867-90 A...... 4500-NO3- F..... 4500-NO3- F.... 4500-NO3- F-00
Cadmium
Reduction.
Ion Selective ................ ................ 4500-NO3- D..... 4500-NO3- D.... 4500-NO3- D-00. 601 \7\
Electrode.
[[Page 455]]
Manual Cadmium ................ D3867-90 B...... 4500-NO3- E..... 4500-NO3- E.... 4500-NO3- E-00
Reduction.
Capillary Ion ................ D6508-00.
Electrophoresis.
19. Nitrite.................. Ion 300.0 \6\, 300.1 D4327-97, 03.... 4110 B.......... 4110 B......... 4110 B-00...... B-1011 \8\
Chromatography. \19\.
Automated 353.2 \6\....... D3867-90 A...... 4500-NO3- F..... 4500-NO3- F.... 4500-NO3- F-00
Cadmium
Reduction.
Manual Cadmium ................ D3867-90 B...... 4500-NO3- E..... 4500-NO3- E.... 4500-NO3- E-00
Reduction.
Spectrophotometr ................ ................ 4500-NO2- B..... 4500-NO2- B.... 4500-NO2- B-00
ic.
Capillary Ion ................ D6508-00
Electrophoresis.
20. Ortho-phosphate.......... Colorimetric, 365.1 \6\....... ................ 4500-P F........ 4500-P F
Automated,
Ascorbic Acid.
Colorimetric, ................ D515-88 A....... 4500-P E........ 4500-P E
ascorbic acid,
single reagent.
Colorimetric ................ ................ ................ ............... ............... I-1601-85 \5\
Phosphomolybdat I-2601-90 \5\
e; Automated- I-2598-85 \5\
segmented flow;
Automated
Discrete.
Ion 300.0 \6\, 300.1 D4327-97, 03.... 4110 B.......... 4110 B......... 4110 B-00
Chromatography. \19\.
Capillary Ion ................ D6508-00
Electrophoresis.
21. pH....................... Electrometric... 150.1, 150.2 \1\ D1293-95, 99.... 4500-H\ + \ B... 4500-H\ + \ B.. 4500-H\ + \ B-
00.
22. Selenium................. Hydride-Atomic ................ D3859-98, 03 A.. 3114 B.......... ............... 3114 B-97......
Absorption.
ICP-Mass 200.8 \2\
Spectrometry.
Atomic 200.9 \2\
Absorption;
Platform.
Atomic ................ D3859-98, 03 B.. 3113 B.......... ............... 3113 B-99......
Absorption;
Furnace.
23. Silica................... Colorimetric, ................ ................ ................ ............... ............... I-1700-85 \5\
Molybdate Blue.
Automated- ................ ................ ................ ............... ............... I-2700-85 \5\
segmented
Flow.
Colorimetric.... ................ D859-94, 00.....
Molybdosilicate. ................ ................ 4500-Si D....... 4500-SiO2 C.... 4500-SiO2 C-97.
[[Page 456]]
Heteropoly blue. ................ ................ 4500-Si E....... 4500-SiO2 D.... 4500-SiO2 D-97.
Automated for ................ ................ 4500-Si F....... 4500-SiO2 E.... 4500-SiO2 E-97.
Molybdate-
reactive Silica.
Inductively 200.7 \2\....... ................ 3120 B.......... 3120 B......... 3120 B-99......
Coupled Plasma.
24. Sodium................... Inductively 200.7 \2\
Coupled Plasma.
Atomic ................ ................ 3111 B.......... ............... 3111 B-99......
Absorption;
Direct
Aspiration.
Ion ................ D6919-03........
Chromatography.
25. Temperature.............. Thermometric.... ................ ................ 2550............ 2550........... 2550-00........
26. Thallium................. ICP-Mass 200.8 \2\
Spectrometry.
Atomic 200.9 \2\ ......
Absorption;
Platform.
--------------------------------------------------------------------------------------------------------------------------------------------------------
The procedures shall be done in accordance with the documents listed below. The incorporation by reference of the following documents listed in
footnotes 1-11, 16-20, and 22-23 was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of
the documents may be obtained from the sources listed below. Information regarding obtaining these documents can be obtained from the Safe Drinking
Water Hotline at 800-426-4791. Documents may be inspected at EPA's Drinking Water Docket, EPA West, 1301 Constitution Avenue, NW., Room 3334,
Washington, DC 20460 (Telephone: 202-566-2426); or at the National Archives and Records Administration (NARA). For information on the availability of
this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.
\1\ ``Methods for Chemical Analysis of Water and Wastes,'' EPA/600/4-79/020, March 1983. Available at NTIS, PB84-128677.
\2\ ``Methods for the Determination of Metals in Environmental Samples--Supplement I,'' EPA/600/R-94/111, May 1994. Available at NTIS, PB95-125472.
\3\ Annual Book of ASTM Standards, ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, http://www.astm.org.; Annual Book of ASTM
Standards 1994, Vols. 11.01 and 11.02; Annual Book of ASTM Standards 1996, Vols. 11.01 and 11.02; Annual Book of ASTM Standards 1999, Vols. 11.01 and
11.02; Annual Book of ASTM Standards 2003, Vols. 11.01 and 11.02.
\4\ Standard Methods for the Examination of Water and Wastewater, American Public Health Association, 800 I Street NW., Washington, DC 20001-3710;
Standard Methods for the Examination of Water and Wastewater, 18th edition (1992); Standard Methods for the Examination of Water and Wastewater, 19th
edition (1995); Standard Methods for the Examination of Water and Wastewater, 20th edition (1998).The following methods from this edition cannot be
used: 3111 B, 3111 D, 3113 B, and 3114 B.
\5\ U.S. Geological Survey, Federal Center, Box 25286, Denver, CO 80225-0425; Methods for Analysis by the U.S. Geological Survey National Water Quality
Laboratory--Determination of Inorganic and Organic Constituents in Water and Fluvial Sediment, Open File Report 93-125, 1993; Techniques of Water
Resources Investigation of the U.S. Geological Survey, Book 5, Chapter A-1, 3rd edition, 1989.
\6\ ``Methods for the Determination of Inorganic Substances in Environmental Samples,'' EPA/600/R-93/100, August 1993. Available as Technical Report
PB94-120821 at National Technical Information Service (NTIS), 5301 Shawnee Road, Alexandria, VA 22312. http://www.ntis.gov.
\7\ The procedure shall be done in accordance with the Technical Bulletin 601 ``Standard Method of Test for Nitrate in Drinking Water,'' July 1994, PN
221890-001, Analytical Technology, Inc. Copies may be obtained from ATI Orion, 529 Main Street, Boston, MA 02129.
\8\ Method B-1011. ``Waters Test Method for Determination of Nitrite/Nitrate in Water Using Single Column Ion Chromatography,'' August, 1987. Copies may
be obtained from Waters Corporation, Technical Services Division, 34 Maple Street, Milford, MA 01757, Telephone: 508/482-2963, Fax: 508/482-4056.
\9\ Method 100.1, ``Analytical Method For Determination of Asbestos Fibers in Water,'' EPA/600/4-83/043, EPA, September 1983. Available at NTIS, PB83-
260471.
\10\ Method 100.2, ``Determination of Asbestos Structure Over 10-[mu]m In Length In Drinking Water,'' EPA/600/R-94/134, June 1994. Available at NTIS,
PB94-201902.
\11\ Industrial Method No. 129-71W, ``Fluoride in Water and Wastewater,'' December 1972, and Method No. 380-75WE, ``Fluoride in Water and Wastewater,''
February 1976, Technicon Industrial Systems. Copies may be obtained from Bran & Luebbe, 1025 Busch Parkway, Buffalo Grove, IL 60089.
\12\ Unfiltered, no digestion or hydrolysis.
\13\ Because MDLs reported in EPA Methods 200.7 and 200.9 were determined using a 2x preconcentration step during sample digestion, MDLs determined when
samples are analyzed by direct analysis (i.e., no sample digestion) will be higher. For direct analysis of cadmium and arsenic by Method 200.7, and
arsenic by Method 3120 B, sample preconcentration using pneumatic nebulization may be required to achieve lower detection limits. Preconcentration may
also be required for direct analysis of antimony, lead, and thallium by Method 200.9; antimony and lead by Method 3113 B; and lead by Method D3559-
90D, unless multiple in-furnace depositions are made.
\14\ If ultrasonic nebulization is used in the determination of arsenic by Method 200.8, the arsenic must be in the pentavalent state to provide uniform
signal response. For direct analysis of arsenic with Method 200.8 using ultrasonic nebulization, samples and standards must contain 1 mg/L of sodium
hypochlorite.
\15\ [Reserved]
[[Page 457]]
\16\ The description for Method Number 1001 for lead is available from Palintest, LTD, 21 Kenton Lands Road, P.O. Box 18395, Erlanger, KY 41018. Or from
the Hach Company, P.O. Box 389, Loveland, CO 80539.
\17\ The description for the Kelada-01 Method, ``Kelada Automated Test Methods for Total Cyanide, Acid Dissociable Cyanide, And Thiocyanate,'' Revision
1.2, August 2001, EPA 821-B-01-009 for cyanide is available from the National Technical Information Service (NTIS), PB 2001-108275, 5285 Port Royal
Road, Springfield, VA 22161. The toll free telephone number is 800-553-6847. Note: A 450-W UV lamp may be used in this method instead of the 550-W
lamp specified if it provides performance within the quality control (QC) acceptance criteria of the method in a given instrument. Similarly, modified
flow cell configurations and flow conditions may be used in the method, provided that the QC acceptance criteria are met.
\18\ The description for the QuikChem Method 10-204-00-1-X, ``Digestion and distillation of total cyanide in drinking and wastewaters using MICRO DIST
and determination of cyanide by flow injection analysis,'' Revision 2.1, November 30, 2000, for cyanide is available from Lachat Instruments, 6645 W.
Mill Rd., Milwaukee, WI 53218. Telephone: 414-358-4200.
\19\ ``Methods for the Determination of Organic and Inorganic Compounds in Drinking Water,'' Vol. 1, EPA 815-R-00-014, August 2000. Available as
Technical Report PB2000-106981 at National Technical Information Service (NTIS), 5301 Shawnee Road, Alexandria, VA 22312. http://www.ntis.gov.
\20\ Method OIA-1677, DW ``Available Cyanide by Flow Injection, Ligand Exchange, and Amperometry,'' January 2004. EPA-821-R-04-001, Available from
ALPKEM, A Division of OI Analytical, P.O. Box 9010, College Station, TX 77842-9010.
\21\ Sulfide levels below those detected using lead acetate paper may produce positive method interferences. Test samples using a more sensitive sulfide
method to determine if a sulfide interference is present, and treat samples accordingly.
\22\ Standard Methods Online, American Public Health Association, 800 I Street NW., Washington, DC 20001, available at http://www.standardmethods.org.
The year in which each method was approved by the Standard Methods Committee is designated by the last two digits in the method number. The methods
listed are the only online versions that may be used.
[[Page 458]]
(2) Sample collection for antimony, arsenic, asbestos, barium,
beryllium, cadmium, chromium, cyanide, fluoride, mercury, nickel,
nitrate, nitrite, selenium, and thallium under this section shall be
conducted using the sample preservation, container, and maximum holding
time procedures specified in the table below:
------------------------------------------------------------------------
Container
Contaminant Preservative \1\ \2\ Time \3\
------------------------------------------------------------------------
Antimony..................... HNO\3\.......... P or G.... 6 months
Arsenic...................... Conc HNO3 to pH P or G.... 6 months
<2.
Asbestos..................... 4 [deg]C........ P or G.... 48 hours
\4\
Barium....................... HNO\3\.......... P or G.... 6 months
Beryllium.................... HNO\3\.......... P or G.... 6 months
Cadmium...................... HNO\3\.......... P or G.... 6 months
Chromium..................... HNO\3\.......... P or G.... 6 months
Cyanide...................... 4 [deg]C, NaOH.. P or G.... 14 days
Fluoride..................... None............ P or G.... 1 month
Mercury...................... HNO\3\.......... P or G.... 28 days
Nickel....................... HNO\3\.......... P or G.... 6 months
Nitrate...................... 4 [deg]C........ P or G.... 48 hours
\5\
Nitrate-Nitrite \6\.......... H\2\SO\4\....... P or G.... 28 days
Nitrite...................... 4 [deg]C........ P or G.... 48 hours
Selenium..................... HNO\3\.......... P or G.... 6 months
Thallium..................... HNO\3\.......... P or G.... 6 months
------------------------------------------------------------------------
\1\ For cyanide determinations samples must be adjusted with sodium
hydroxide to pH 12 at the time off collection. When chilling is
indicated the sample must be shipped and stored at 4 [deg]C or less.
Acidification of nitrate or metals samples may be with a concentrated
acid or a dilute (50% by volume) solution of the applicable
concentrated acid. Acidification of samples for metals analysis is
encouraged and allowed at the laboratory rather than at the time of
sampling provided the shipping time and other instructions in Section
8.3 of EPA Methods 200.7 or 200.8 or 200.9 are followed.
\2\ P = plastic, hard or soft; G = glass, hard or soft.
\3\ In all cases samples should be analyzed as soon after collection as
possible. Follow additional (if any) information on preservation,
containers or holding times that is specified in method.
\4\ Instructions for containers, preservation procedures and holding
times as specified in Method 100.2 must be adhered to for all
compliance analyses including those conducted with Method 100.1.
\5\ If the sample is chlorinated, the holding time for an unacidified
sample kept at 4 [deg]C is extended to 14 days.
\6\ Nitrate-Nitrite refers to a measurement of total nitrate.
(3) Analysis under this section shall only be conducted by
laboratories that have been certified by EPA or the State. Laboratories
may conduct sample analysis under provisional certification until
January 1, 1996. To receive certification to conduct analyses for
antimony, arsenic, asbestos, barium, beryllium, cadmium, chromium,
cyanide, fluoride, mercury, nickel, nitrate, nitrite and selenium and
thallium, the laboratory must:
(i) Analyze Performance Evaluation (PE) samples provided by EPA, the
State or by a third party (with the approval of the State or EPA) at
least once a year.
(ii) For each contaminant that has been included in the PE sample
and for each method for which the laboratory desires certification
achieve quantitative results on the analyses that are within the
following acceptance limits:
------------------------------------------------------------------------
Contaminant Acceptance limit
------------------------------------------------------------------------
Antimony............................ 30 at =0.006 mg/1
Arsenic............................. 30 at =0.003 mg/L
Asbestos............................ 2 standard deviations based on
study statistics.
Barium.............................. 15% at =0.15 mg/1
Beryllium........................... 15% at =0.001 mg/1
Cadmium............................. 20% at =0.002 mg/1
Chromium............................ 15% at =0.01 mg/1
Cyanide............................. 25% at =0.1 mg/1
Fluoride............................ 10% at =1 to 10 mg/1
Mercury............................. 30% at =0.0005 mg/1
Nickel.............................. 15% at =0.01 mg/1
Nitrate............................. 10% at =0.4 mg/1
Nitrite............................. 15% at =0.4 mg/1
Selenium............................ 20% at =0.01 mg/1
Thallium............................ 30% at =0.002 mg/1
------------------------------------------------------------------------
(l) Analyses for the purpose of determining compliance with Sec.
141.11 shall be conducted using the requirements specified in paragraphs
(l) through (q) of this section.
(1) Analyses for all community water systems utilizing surface water
sources shall be completed by June 24, 1978. These analyses shall be
repeated at yearly intervals.
(2) Analyses for all community water systems utilizing only ground
water sources shall be completed by June 24, 1979. These analyses shall
be repeated at three-year intervals.
(3) For non-community water systems, whether supplied by surface or
ground sources, analyses for nitrate shall be completed by December 24,
1980. These analyses shall be repeated at intervals determined by the
State.
(4) The State has the authority to determine compliance or initiate
enforcement action based upon analytical results and other information
compiled by their sanctioned representatives and agencies.
(m) If the result of an analysis made under paragraph (l) of this
section indicates that the level of any contaminant listed in Sec.
141.11 exceeds the maximum contaminant level, the supplier of the water
shall report to the State within 7 days and initiate three additional
analyses at the same sampling point within one month.
[[Page 459]]
(n) When the average of four analyses made pursuant to paragraph (m)
of this section, rounded to the same number of significant figures as
the maximum contaminant level for the substance in question, exceeds the
maximum contaminant level, the supplier of water shall notify the State
pursuant to Sec. 141.31 and give notice to the public pursuant to
subpart Q. Monitoring after public notification shall be at a frequency
designated by the State and shall continue until the maximum contaminant
level has not been exceeded in two successive samples or until a
monitoring schedule as a condition to a variance, exemption or
enforcement action shall become effective.
(o) The provisions of paragraphs (m) and (n) of this section
notwithstanding, compliance with the maximum contaminant level for
nitrate shall be determined on the basis of the mean of two analyses.
When a level exceeding the maximum contaminant level for nitrate is
found, a second analysis shall be initiated within 24 hours, and if the
mean of the two analyses exceeds the maximum contaminant level, the
supplier of water shall report his findings to the State pursuant to
Sec. 141.31 and shall notify the public pursuant to subpart Q.
(p) For the initial analyses required by paragraph (l) (1), (2) or
(3) of this section, data for surface waters acquired within one year
prior to the effective date and data for ground waters acquired within 3
years prior to the effective date of this part may be substituted at the
discretion of the State.
(q) [Reserved]
[56 FR 3579, Jan. 30, 1991]
Editorial Note: For Federal Register citations affecting Sec.
141.23, see the List of CFR Sections Affected, which appears in the
Finding Aids section of the printed volume and at www.fdsys.gov.
Sec. 141.24 Organic chemicals, sampling and analytical requirements.
(a)-(d) [Reserved]
(e) Analyses for the contaminants in this section shall be conducted
using the methods listed in the following table, or the alternative
methods listed in appendix A to subpart C of this part, or their
equivalent as determined by EPA.
(1) The following documents are incorporated by reference. This
incorporation by reference was approved by the Director of the Federal
Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies
may be inspected at EPA's Drinking Water Docket, 1301 Constitution
Avenue, NW., EPA West, Room 3334, Washington, DC 20460 (Telephone: 202-
566-2426); or at the National Archives and Records Administration
(NARA). For information on the availability of this material at NARA,
call 202-741-6030, or go to: http://www.archives.gov/federal_register/
code_of_federal_regulations/ibr_locations.html. Method 508A and 515.1
are in Methods for the Determination of Organic Compounds in Drinking
Water, EPA/600/4-88-039, December 1988, Revised, July 1991. Methods 547,
550 and 550.1 are in Methods for the Determination of Organic Compounds
in Drinking Water--Supplement I, EPA/600-4-90-020, July 1990. Methods
548.1, 549.1, 552.1 and 555 are in Methods for the Determination of
Organic Compounds in Drinking Water--Supplement II, EPA/600/R-92-129,
August 1992. Methods 502.2, 504.1, 505, 506, 507, 508, 508.1, 515.2,
524.2 525.2, 531.1, 551.1 and 552.2 are in Methods for the Determination
of Organic Compounds in Drinking Water--Supplement III, EPA/600/R-95-
131, August 1995. Method 1613 is titled ``Tetra-through Octa-Chlorinated
Dioxins and Furans by Isotope-Dilution HRGC/HRMS,'' EPA/821-B-94-005,
October 1994. These documents are available from the National Technical
Information Service, NTIS PB91-231480, PB91-146027, PB92-207703, PB95-
261616 and PB95-104774, U.S. Department of Commerce, 5285 Port Royal
Road, Springfield, Virginia 22161. The toll free number is: 800-553-
6847. Method 6651 shall be followed in accordance with Standard Methods
for the Examination of Water and Wastewater, 18th edition (1992), 19th
edition (1995), or 20th edition (1998), American Public Health
Association (APHA); any of these three editions may be used. Method 6610
shall be followed in accordance with Standard Methods for the
Examination of Water and Wastewater, (18th Edition Supplement) (1994),
or with the 19th edition (1995) or 20th edition (1998) of Standard
Methods for the Examination of Water and Wastewater;
[[Page 460]]
any of these publications may be used. The APHA documents are available
from APHA, 1015 Fifteenth Street NW., Washington, DC 20005. Other
required analytical test procedures germane to the conduct of these
analyses are contained in Technical Notes on Drinking Water Methods,
EPA/600/R-94-173, October 1994, NTIS PB95-104766. EPA Methods 515.3 and
549.2 are available from U.S. Environmental Protection Agency, National
Exposure Research Laboratory (NERL)-Cincinnati, 26 West Martin Luther
King Drive, Cincinnati, OH 45268. ASTM Method D 5317-93, 98 (Reapproved
2003) is available in the Annual Book of ASTM Standards, (1999), Vol.
11.02, ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA
19428, any edition containing the cited version of the method may be
used. EPA Method 515.4, ``Determination of Chlorinated Acids in Drinking
Water by Liquid-Liquid Microextraction, Derivatization and Fast Gas
Chromatography with Electron Capture Detection,'' Revision 1.0, April
2000, EPA/815/B-00/001 and EPA Method 552.3, ``Determination of
Haloacetic Acids and Dalapon in Drinking Water by Liquid-Liquid
Microextraction, Derivatization, and Gas Chromatography with Electron
Capture Detection,'' Revision 1.0, July 2003, EPA 815-B-03-002, can be
accessed and downloaded directly online at http://www.epa.gov/safewater/
methods/sourcalt.html. Syngenta Method AG-625, ``Atrazine in Drinking
Water by Immunoassay,'' February 2001, is available from Syngenta Crop
Protection, Inc., 410 Swing Road, P.O. Box 18300, Greensboro, NC 27419.
Telephone: 336-632-6000. Method 531.2 ``Measurement of N-
methylcarbamoyloximes and N-methylcarbamates in Water by Direct Aqueous
Injection HPLC with Postcolumn Derivatization,'' Revision 1.0, September
2001, EPA 815-B-01-002, can be accessed and downloaded directly online
at http://www.epa.gov/safewater/methods/sourcalt.html.
----------------------------------------------------------------------------------------------------------------
Contaminant EPA method Standard methods ASTM Other
----------------------------------------------------------------------------------------------------------------
1. Benzene........................ 502.2, 524.2........
2. Carbon tetrachloride........... 502.2, 524.2, 551.1.
3. Chlorobenzene.................. 502.2, 524.2........
4. 1,2-Dichlorobenzene............ 502.2, 524.2........
5. 1,4-Dichlorobenzene............ 502.2, 524.2........
6. 1,2-Dichloroethane............. 502.2, 524.2........
7. cis-Dichloroethylene........... 502.2, 524.2........
8. trans-Dichloroethylene......... 502.2, 524.2........
9. Dichloromethane................ 502.2, 524.2........
10. 1,2-Dichloropropane........... 502.2, 524.2........
11. Ethylbenzene.................. 502.2, 524.2........
12. Styrene....................... 502.2, 524.2........
13. Tetrachloroethylene........... 502.2, 524.2, 551.1.
14. 1,1,1-Trichloroethane......... 502.2, 524.2, 551.1.
15. Trichloroethylene............. 502.2, 524.2, 551.1.
16. Toluene....................... 502.2, 524.2........
17. 1,2,4-Trichlorobenzene........ 502.2, 524.2........
18. 1,1-Dichloroethylene.......... 502.2, 524.2........
19. 1,1,2-Trichloroethane......... 502.2, 524.2, 551.1.
20. Vinyl chloride................ 502.2, 524.2........
21. Xylenes (total)............... 502.2, 524.2........
22. 2,3,7,8-TCDD (dioxin)......... 1613................
23. 2,4-D \4\ (as acids, salts, 515.2, 555, 515.1, .................... D5317-93, 98
and esters). 515.3, 515.4. (Reapproved
2003).
24. 2,4,5-TP \4\ (Silvex)......... 515.2, 555, 515.1, .................... D5317-93, 98
515.3, 515.4. (Reapproved
2003).
25. Alachlor \2\.................. 507, 525.2, 508.1,
505, 551.1.
26. Atrazine \2\.................. 507, 525.2, 508.1, .................... ............... Syngenta \5\ AG-
505, 551.1. 625
27. Benzo(a)pyrene................ 525.2, 550, 550.1...
28. Carbofuran.................... 531.1, 531.2........ 6610................
29. Chlordane..................... 508, 525.2, 508.1,
505.
30. Dalapon....................... 552.1 515.1, 552.2,
515.3, 515.4, 552.3.
[[Page 461]]
31. Di(2-ethylhexyl)adipate....... 506, 525.2..........
32. Di(2-ethylhexyl)phthalate..... 506, 525.2..........
33. Dibromochloropropane (DBCP)... 504.1, 551.1........
34. Dinoseb \4\................... 515.2, 555, 515.1,
515.3, 515.4.
35. Diquat........................ 549.2...............
36. Endothall..................... 548.1...............
37. Endrin........................ 508, 525.2, 508.1,
505, 551.1.
38. Ethylene dibromide (EDB)...... 504.1, 551.1........
39. Glyphosate.................... 547................. 6651................
40. Heptachlor.................... 508, 525.2, 508.1,
505, 551.1.
41. Heptachlor Epoxide............ 508, 525.2, 508.1,
505, 551.1.
42. Hexachlorobenzene............. 508, 525.2, 508.1,
505, 551.1.
43. Hexachlorocyclopentadiene..... 508, 525.2, 508.1,
505, 551.1.
44. Lindane....................... 508, 525.2, 508.1,
505, 551.1.
45. Methoxychlor.................. 508, 525.2, 508.1,
505, 551.1.
46. Oxamyl........................ 531.1, 531.2........ 6610................
47. PCBs \3\ (as 508A................
decachlorobiphenyl).
48. PCBs \3\ (as Aroclors)........ 508.1, 508, 525.2,
505.
49. Pentachlorophenol............. 515.2, 525.2, 555, .................... D5317-93, 98
515.1, 515.3, 515.4. (Reapproved
2003).
50. Picloram \4\.................. 515.2, 555, 515.1, .................... D5317-93, 98
515.3, 515.4. (Reapproved
2003).
51. Simazine \2\.................. 507, 525.2, 508.1,
505, 551.1.
52. Toxaphene..................... 508, 508.1, 525.2,
505.
53. Total Trihalomethanes......... 502.2, 524.2, 551.1.
----------------------------------------------------------------------------------------------------------------
\1\ [Reserved]
\2\ Substitution of the detector specified in Method 505, 507, 508 or 508.1 for the purpose of achieving lower
detection limits is allowed as follows. Either an electron capture or nitrogen phosphorous detector may be
used provided all regulatory requirements and quality control criteria are met.
\3\ PCBs are qualitatively identified as Aroclors and measured for compliance purposes as decachlorobiphenyl.
Users of Method 505 may have more difficulty in achieving the required detection limits than users of Methods
508.1, 525.2 or 508.
\4\ Accurate determination of the chlorinated esters requires hydrolysis of the sample as described in EPA
Methods 515.1, 515.2, 515.3, 515.4 and 555 and ASTM Method D5317-93.
\5\ This method may not be used for the analysis of atrazine in any system where chlorine dioxide is used for
drinking water treatment. In samples from all other systems, any result for atrazine generated by Method AG-
625 that is greater than one-half the maximum contaminant level (MCL) (in other words, greater than 0.0015mg/L
or 1.5 [mu]g/L) must be confirmed using another approved method for this contaminant and should use additional
volume of the original sample collected for compliance monitoring. In instances where a result from Method AG-
625 triggers such confirmatory testing, the confirmatory result is to be used to determine compliance.
(2) [Reserved]
(f) Beginning with the initial compliance period, analysis of the
contaminants listed in Sec. 141.61(a) (1) through (21) for the purpose
of determining compliance with the maximum contaminant level shall be
conducted as follows:
(1) Groundwater systems shall take a minimum of one sample at every
entry point to the distribution system which is representative of each
well after treatment (hereafter called a sampling point). Each sample
must be taken at the same sampling point unless conditions make another
sampling point more representative of each source, treatment plant, or
within the distribution system.
(2) Surface water systems (or combined surface/ground) shall take a
minimum of one sample at points in the distribution system that are
representative of each source or at each entry point to the distribution
system after treatment (hereafter called a sampling point). Each sample
must be taken at the same sampling point unless conditions make another
sampling point more representative of each source, treatment plant, or
within the distribution system.
(3) If the system draws water from more than one source and the
sources are combined before distribution, the system must sample at an
entry point to the distribution system during periods of normal
operating conditions
[[Page 462]]
(i.e., when water representative of all sources is being used).
(4) Each community and non-transient non-community water system
shall take four consecutive quarterly samples for each contaminant
listed in Sec. 141.61(a) (2) through (21) during each compliance
period, beginning in the initial compliance period.
(5) If the initial monitoring for contaminants listed in Sec.
141.61(a) (1) through (8) and the monitoring for the contaminants listed
in Sec. 141.61(a) (9) through (21) as allowed in paragraph (f)(18) has
been completed by December 31, 1992, and the system did not detect any
contaminant listed in Sec. 141.61(a) (1) through (21), then each ground
and surface water system shall take one sample annually beginning with
the initial compliance period.
(6) After a minimum of three years of annual sampling, the State may
allow groundwater systems with no previous detection of any contaiminant
listed in Sec. 141.61(a) to take one sample during each compliance
period.
(7) Each community and non-transient non-community ground water
system which does not detect a contaminant listed in Sec. 141.61(a) (1)
through (21) may apply to the State for a waiver from the requirements
of paragraphs (f)(5) and (f)(6) of this section after completing the
initial monitoring. (For purposes of this section, detection is defined
as =0.0005 mg/l.) A waiver shall be effective for no more
than six years (two compliance periods). States may also issue waivers
to small systems for the initial round of monitoring for 1,2,4-
trichlorobenzene.
(8) A State may grant a waiver after evaluating the following
factor(s):
(i) Knowledge of previous use (including transport, storage, or
disposal) of the contaminant within the watershed or zone of influence
of the system. If a determination by the State reveals no previous use
of the contaminant within the watershed or zone of influence, a waiver
may be granted.
(ii) If previous use of the contaminant is unknown or it has been
used previously, then the following factors shall be used to determine
whether a waiver is granted.
(A) Previous analytical results.
(B) The proximity of the system to a potential point or non-point
source of contamination. Point sources include spills and leaks of
chemicals at or near a water treatment facility or at manufacturing,
distribution, or storage facilities, or from hazardous and municipal
waste landfills and other waste handling or treatment facilities.
(C) The environmental persistence and transport of the contaminants.
(D) The number of persons served by the public water system and the
proximity of a smaller system to a larger system.
(E) How well the water source is protected against contamination,
such as whether it is a surface or groundwater system. Groundwater
systems must consider factors such as depth of the well, the type of
soil, and wellhead protection. Surface water systems must consider
watershed protection.
(9) As a condition of the waiver a groundwater system must take one
sample at each sampling point during the time the waiver is effective
(i.e., one sample during two compliance periods or six years) and update
its vulnerability assessment considering the factors listed in paragraph
(f)(8) of this section. Based on this vulnerability assessment the State
must reconfirm that the system is non-vulnerable. If the State does not
make this reconfirmation within three years of the initial
determination, then the waiver is invalidated and the system is required
to sample annually as specified in paragraph (5) of this section.
(10) Each community and non-transient non-community surface water
system which does not detect a contaminant listed in Sec. 141.61(a) (1)
through (21) may apply to the State for a waiver from the requirements
of (f)(5) of this section after completing the initial monitoring.
Composite samples from a maximum of five sampling points are allowed,
provided that the detection limit of the method used for analysis is
less than one-fifth of the MCL. Systems meeting this criterion must be
determined by the State to be non-vulnerable based on a vulnerability
assessment during each compliance period. Each system receiving a waiver
shall sample at the frequency specified by the State (if any).
[[Page 463]]
(11) If a contaminant listed in Sec. 141.61(a) (2) through (21) is
detected at a level exceeding 0.0005 mg/l in any sample, then:
(i) The system must monitor quarterly at each sampling point which
resulted in a detection.
(ii) The State may decrease the quarterly monitoring requirement
speci fied in paragraph (f)(11)(i) of this section provided it has
determined that the system is reliably and consistently below the
maximum contaminant level. In no case shall the State make this
determination unless a groundwater system takes a minimum of two
quarterly samples and a surface water system takes a minimum of four
quarterly samples.
(iii) If the State determines that the system is reliably and
consistently below the MCL, the State may allow the system to monitor
annually. Systems which monitor annually must monitor during the
quarter(s) which previously yielded the highest analytical result.
(iv) Systems which have three consecutive annual samples with no
detection of a contaminant may apply to the State for a waiver as
specified in paragraph (f)(7) of this section.
(v) Groundwater systems which have detected one or more of the
following two-carbon organic compounds: trichloroethylene,
tetrachloroethylene, 1,2-dichloroethane, 1,1,1-trichloroethane, cis-1,2-
dichloroethylene, trans-1,2-dichloroethylene, or 1,1-dichloroethylene
shall monitor quarterly for vinyl chloride. A vinyl chloride sample
shall be taken at each sampling point at which one or more of the two-
carbon organic compounds was detected. If the results of the first
analysis do not detect vinyl chloride, the State may reduce the
quarterly monitoring frequency of vinyl chloride monitoring to one
sample during each compliance period. Surface water systems are required
to monitor for vinyl chloride as specified by the State.
(12) Systems which violate the requirements of Sec. 141.61(a) (1)
through (21), as determined by paragraph (f)(15) of this section, must
monitor quarterly. After a minimum of four consecutive quarterly samples
which show the system is in compliance as specified in paragraph (f)(15)
of this section the system and the State determines that the system is
reliably and consistently below the maximum contaminant level, the
system may monitor at the frequency and times specified in paragraph
(f)(11)(iii) of this section.
(13) The State may require a confirmation sample for positive or
negative results. If a confirmation sample is required by the State, the
result must be averaged with the first sampling result and the average
is used for the compliance determination as specified by paragraph
(f)(15). States have discretion to delete results of obvious sampling
errors from this calculation.
(14) The State may reduce the total number of samples a system must
analyze by allowing the use of compositing. Composite samples from a
maximum of five sampling points are allowed, provided that the detection
limit of the method used for analysis is less than one-fifth of the MCL.
Compositing of samples must be done in the laboratory and analyzed
within 14 days of sample collection.
(i) If the concentration in the composite sample is greater than or
equal to 0.0005 mg/l for any contaminant listed in Sec. 141.61(a), then
a follow-up sample must be taken within 14 days at each sampling point
included in the composite, and be analyzed for that contaminant.
(ii) If duplicates of the original sample taken from each sampling
point used in the composite sample are available, the system may use
these instead of resampling. The duplicates must be analyzed and the
results reported to the State within 14 days after completing analysis
of the composite sample, provided the holding time of the sample is not
exceeded.
(iii) If the population served by the system is 3,300
persons, then compositing may only be permitted by the State at sampling
points within a single system. In systems serving <=3,300 persons, the
State may permit compositing among different systems provided the 5-
sample limit is maintained.
(iv) Compositing samples prior to GC analysis.
[[Page 464]]
(A) Add 5 ml or equal larger amounts of each sample (up to 5 samples
are allowed) to a 25 ml glass syringe. Special precautions must be made
to maintain zero headspace in the syringe.
(B) The samples must be cooled at 4 [deg]C during this step to
minimize volatilization losses.
(C) Mix well and draw out a 5-ml aliquot for analysis.
(D) Follow sample introduction, purging, and desorption steps
described in the method.
(E) If less than five samples are used for compositing, a
proportionately small syringe may be used.
(v) Compositing samples prior to GC/MS analysis.
(A) Inject 5-ml or equal larger amounts of each aqueous sample (up
to 5 samples are allowed) into a 25-ml purging device using the sample
introduction technique described in the method.
(B) The total volume of the sample in the purging device must be 25
ml.
(C) Purge and desorb as described in the method.
(15) Compliance with Sec. 141.61(a) (1) through (21) shall be
determined based on the analytical results obtained at each sampling
point. If one sampling point is in violation of an MCL, the system is in
violation of the MCL.
(i) For systems monitoring more than once per year, compliance with
the MCL is determined by a running annual average at each sampling
point.
(ii) Systems monitoring annually or less frequently whose sample
result exceeds the MCL must begin quarterly sampling. The system will
not be considered in violation of the MCL until it has completed one
year of quarterly sampling.
(iii) If any sample result will cause the running annual average to
exceed the MCL at any sampling point, the system is out of compliance
with the MCL immediately.
(iv) If a system fails to collect the required number of samples,
compliance will be based on the total number of samples collected.
(v) If a sample result is less than the detection limit, zero will
be used to calculate the annual average.
(16) [Reserved]
(17) Analysis under this section shall only be conducted by
laboratories that are certified by EPA or the State according to the
following conditions (laboratories may conduct sample analysis under
provisional certification until January 1, 1996):
(i) To receive certification to conduct analyses for the
contaminants in Sec. 141.61(a) (2) through (21) the laboratory must:
(A) Analyze Performance Evaluation (PE) samples provided by EPA, the
State, or by a third party (with the approval of the State or EPA) at
least once a year by each method for which the laboratory desires
certification.
(B) Achieve the quantitative acceptance limits under paragraphs
(f)(17)(i)(C) and (D) of this section for at least 80 percent of the
regulated organic contaminants included in the PE sample.
(C) Achieve quantitative results on the analyses performed under
paragraph (f)(17)(i)(A) of this section that are within 20% of the actual amount of the substances in the
Performance Evaluation sample when the actual amount is greater than or
equal to 0.010 mg/l.
(D) Achieve quantitative results on the analyses performed under
paragraph (f)(17)(i)(A) of this section that are within 40 percent of the actual amount of the substances in the
Performance Evaluation sample when the actual amount is less than 0.010
mg/l.
(E) Achieve a method detection limit of 0.0005 mg/l, according to
the procedures in appendix B of part 136.
(ii) To receive certification to conduct analyses for vinyl
chloride, the laboratory must:
(A) Analyze Performance Evaluation (PE) samples provided by EPA, the
State, or by a third party (with the approval of the State or EPA) at
least once a year by each method for which the laboratory desires
certification.
(B) Achieve quantitative results on the analyses performed under
paragraph (f)(17)(ii)(A) of this section that are within 40 percent of the actual amount of vinyl chloride in the
Performance Evaluation sample.
(C) Achieve a method detection limit of 0.0005 mg/l, according to
the procedures in appendix B of part 136.
[[Page 465]]
(D) Obtain certification for the contaminants listed in Sec.
141.61(a)(2) through (21).
(18) States may allow the use of monitoring data collected after
January 1, 1988, required under section 1445 of the Act for purposes of
initial monitoring compliance. If the data are generally consistent with
the other requirements of this section, the State may use these data
(i.e., a single sample rather than four quarterly samples) to satisfy
the initial monitoring requirement of paragraph (f)(4) of this section.
Systems which use grandfathered samples and did not detect any
contaminant listed Sec. 141.61(a)(2) through (21) shall begin
monitoring annually in accordance with paragraph (f)(5) of this section
beginning with the initial compliance period.
(19) States may increase required monitoring where necessary to
detect variations within the system.
(20) Each certified laboratory must determine the method detection
limit (MDL), as defined in appendix B to part 136, at which it is
capable of detecting VOCs. The acceptable MDL is 0.0005 mg/l. This
concentration is the detection concentration for purposes of this
section.
(21) Each public water system shall monitor at the time designated
by the State within each compliance period.
(22) All new systems or systems that use a new source of water that
begin operation after January 22, 2004 must demonstrate compliance with
the MCL within a period of time specified by the State. The system must
also comply with the initial sampling frequencies specified by the State
to ensure a system can demonstrate compliance with the MCL. Routine and
increased monitoring frequencies shall be conducted in accordance with
the requirements in this section.
(g) [Reserved]
(h) Analysis of the contaminants listed in Sec. 141.61(c) for the
purposes of determining compliance with the maximum contaminant level
shall be conducted as follows, with the exception that no monitoring is
required for aldicarb, aldicarb sulfoxide or aldicarb sulfone:
(1) Groundwater systems shall take a minimum of one sample at every
entry point to the distribution system which is representative of each
well after treatment (hereafter called a sampling point). Each sample
must be taken at the same sampling point unless conditions make another
sampling point more representative of each source or treatment plant.
(2) Surface water systems shall take a minimum of one sample at
points in the distribution system that are representative of each source
or at each entry point to the distribution system after treatment
(hereafter called a sampling point). Each sample must be taken at the
same sampling point unless conditions make another sampling point more
representative of each source or treatment plant.
Note: For purposes of this paragraph, surface water systems include
systems with a combination of surface and ground sources.
(3) If the system draws water from more than one source and the
sources are combined before distribution, the system must sample at an
entry point to the distribution system during periods of normal
operating conditions (i.e., when water representative of all sources is
being used).
(4) Monitoring frequency: (i) Each community and non-transient non-
community water system shall take four consecutive quarterly samples for
each contaminant listed in Sec. 141.61(c) during each compliance period
beginning with the initial compliance period.
(ii) Systems serving more than 3,300 persons which do not detect a
contaminant in the initial compliance period may reduce the sampling
frequency to a minimum of two quarterly samples in one year during each
repeat compliance period.
(iii) Systems serving less than or equal to 3,300 persons which do
not detect a contaminant in the initial compliance period may reduce the
sampling frequency to a minimum of one sample during each repeat
compliance period.
(5) Each community and non-transient water system may apply to the
State for a waiver from the requirement of paragraph (h)(4) of this
section. A system must reapply for a waiver for each compliance period.
[[Page 466]]
(6) A State may grant a waiver after evaluating the following
factor(s): Knowledge of previous use (including transport, storage, or
disposal) of the contaminant within the watershed or zone of influence
of the system. If a determination by the State reveals no previous use
of the contaminant within the watershed or zone of influence, a waiver
may be granted. If previous use of the contaminant is unknown or it has
been used previously, then the following factors shall be used to
determine whether a waiver is granted.
(i) Previous analytical results.
(ii) The proximity of the system to a potential point or non-point
source of contamination. Point sources include spills and leaks of
chemicals at or near a water treatment facility or at manufacturing,
distribution, or storage facilities, or from hazardous and municipal
waste landfills and other waste handling or treatment facilities. Non-
point sources include the use of pesticides to control insect and weed
pests on agricultural areas, forest lands, home and gardens, and other
land application uses.
(iii) The environmental persistence and transport of the pesticide
or PCBs.
(iv) How well the water source is protected against contamination
due to such factors as depth of the well and the type of soil and the
integrity of the well casing.
(v) Elevated nitrate levels at the water supply source.
(vi) Use of PCBs in equipment used in the production, storage, or
distribution of water (i.e., PCBs used in pumps, transformers, etc.).
(7) If an organic contaminant listed in Sec. 141.61(c) is detected
(as defined by paragraph (h)(18) of this section) in any sample, then:
(i) Each system must monitor quarterly at each sampling point which
resulted in a detection.
(ii) The State may decrease the quarterly monitoring requirement
specified in paragraph (h)(7)(i) of this section provided it has
determined that the system is reliably and consistently below the
maximum contaminant level. In no case shall the State make this
determination unless a groundwater system takes a minimum of two
quarterly samples and a surface water system takes a minimum of four
quarterly samples.
(iii) After the State determines the system is reliably and
consistently below the maximum contaminant level the State may allow the
system to monitor annually. Systems which monitor annually must monitor
during the quarter that previously yielded the highest analytical
result.
(iv) Systems which have 3 consecutive annual samples with no
detection of a contaminant may apply to the State for a waiver as
specified in paragraph (h)(6) of this section.
(v) If the monitoring results in detection of one or more of certain
related contaminants (heptachlor and heptachlor epoxide), then
subsequent monitoring shall analyze for all related contaminants.
(8) Systems which violate the requirements of Sec. 141.61(c) as
determined by paragraph (h)(11) of this section must monitor quarterly.
After a minimum of four quarterly samples show the system is in
compliance and the State determines the system is reliably and
consistently below the MCL, as specified in paragraph (h)(11) of this
section, the system shall monitor at the frequency specified in
paragraph (h)(7)(iii) of this section.
(9) The State may require a confirmation sample for positive or
negative results. If a confirmation sample is required by the State, the
result must be averaged with the first sampling result and the average
used for the compliance determination as specified by paragraph (h)(11)
of this section. States have discretion to delete results of obvious
sampling errors from this calculation.
(10) The State may reduce the total number of samples a system must
analyze by allowing the use of compositing. Composite samples from a
maximum of five sampling points are allowed, provided that the detection
limit of the method used for analysis is less than one-fifth of the MCL.
Compositing of samples must be done in the laboratory and analyzed
within 14 days of sample collection.
(i) If the concentration in the composite sample detects one or more
contaminants listed in Sec. 141.61(c), then a follow-up sample must be
taken within
[[Page 467]]
14 days at each sampling point included in the composite, and be
analyzed for that contaminant.
(ii) If duplicates of the original sample taken from each sampling
point used in the composite sample are available, the system may use
these instead of resampling. The duplicates must be analyzed and the
results reported to the State within 14 days after completion of the
composite analysis or before the holding time for the initial sample is
exceeded whichever is sooner.
(iii) If the population served by the system is 3,300
persons, then compositing may only be permitted by the State at sampling
points within a single system. In systems serving <=3,300 persons, the
State may permit compositing among different systems provided the 5-
sample limit is maintained.
(11) Compliance with Sec. 141.61(c) shall be determined based on
the analytical results obtained at each sampling point. If one sampling
point is in violation of an MCL, the system is in violation of the MCL.
(i) For systems monitoring more than once per year, compliance with
the MCL is determined by a running annual average at each sampling
point.
(ii) Systems monitoring annually or less frequently whose sample
result exceeds the regulatory detection level as defined by paragraph
(h)(18) of this section must begin quarterly sampling. The system will
not be considered in violation of the MCL until it has completed one
year of quarterly sampling.
(iii) If any sample result will cause the running annual average to
exceed the MCL at any sampling point, the system is out of compliance
with the MCL immediately.
(iv) If a system fails to collect the required number of samples,
compliance will be based on the total number of samples collected.
(v) If a sample result is less than the detection limit, zero will
be used to calculate the annual average.
(12) [Reserved]
(13) Analysis for PCBs shall be conducted as follows using the
methods in paragraph (e) of this section:
(i) Each system which monitors for PCBs shall analyze each sample
using either Method 508.1, 525.2, 508 or 505. Users of Method 505 may
have more difficulty in achieving the required Aroclor detection limits
than users of Methods 508.1, 525.2 or 508.
(ii) If PCBs (as one of seven Aroclors) are detected (as designated
in this paragraph) in any sample analyzed using Method 505 or 508, the
system shall reanalyze the sample using Method 508A to quantitate PCBs
(as decachlorobiphenyl).
------------------------------------------------------------------------
Detection limit
Aroclor (mg/l)
------------------------------------------------------------------------
1016................................................. 0.00008
1221................................................. 0.02
1232................................................. 0.0005
1242................................................. 0.0003
1248................................................. 0.0001
1254................................................. 0.0001
1260................................................. 0.0002
------------------------------------------------------------------------
(iii) Compliance with the PCB MCL shall be determined based upon the
quantitative results of analyses using Method 508A.
(14) If monitoring data collected after January 1, 1990, are
generally consistent with the requirements of Sec. 141.24(h), then the
State may allow systems to use that data to satisfy the monitoring
requirement for the initial compliance period beginning January 1, 1993.
(15) The State may increase the required monitoring frequency, where
necessary, to detect variations within the system (e.g., fluctuations in
concentration due to seasonal use, changes in water source).
(16) The State has the authority to determine compliance or initiate
enforcement action based upon analytical results and other information
compiled by their sanctioned representatives and agencies.
(17) Each public water system shall monitor at the time designated
by the State within each compliance period.
(18) Detection as used in this paragraph shall be defined as greater
than or equal to the following concentrations for each contaminant.
------------------------------------------------------------------------
Detection
Contaminant limit (mg/
l)
------------------------------------------------------------------------
Alachlor................................................... .0002
Aldicarb................................................... .0005
Aldicarb sulfoxide......................................... .0005
Aldicarb sulfone........................................... .0008
Atrazine................................................... .0001
Benzo[a]pyrene............................................. .00002
Carbofuran................................................. .0009
[[Page 468]]
Chlordane.................................................. .0002
Dalapon.................................................... .001
1,2-Dibromo-3-chloropropane (DBCP)......................... .00002
Di (2-ethylhexyl) adipate.................................. .0006
Di (2-ethylhexyl) phthalate................................ .0006
Dinoseb.................................................... .0002
Diquat..................................................... .0004
2,4-D...................................................... .0001
Endothall.................................................. .009
Endrin..................................................... .00001
Ethylene dibromide (EDB)................................... .00001
Glyphosate................................................. .006
Heptachlor................................................. .00004
Heptachlor epoxide......................................... .00002
Hexachlorobenzene.......................................... .0001
Hexachlorocyclopentadiene.................................. .0001
Lindane.................................................... .00002
Methoxychlor............................................... .0001
Oxamyl..................................................... .002
Picloram................................................... .0001
Polychlorinated biphenyls (PCBs) (as decachlorobiphenyl)... .0001
Pentachlorophenol.......................................... .00004
Simazine................................................... .00007
Toxaphene.................................................. .001
2,3,7,8-TCDD (Dioxin)...................................... .000000005
2,4,5-TP (Silvex).......................................... .0002
------------------------------------------------------------------------
(19) Anaylsis under this section shall only be conducted by
laboratories that have received certification by EPA or the State and
have met the following conditions:
(i) To receive certification to conduct analyses for the
contaminants in Sec. 141.61(c) the laboratory must:
(A) Analyze Performance Evaluation (PE) samples provided by EPA, the
State, or by a third party (with the approval of the State or EPA) at
least once a year by each method for which the laboratory desires
certification.
(B) For each contaminant that has been included in the PE sample
achieve quantitative results on the analyses that are within the
following acceptance limits:
------------------------------------------------------------------------
Contaminant Acceptance limits (percent)
------------------------------------------------------------------------
DBCP...................................... 40
EDB....................................... 40.
Alachlor.................................. 45.
Atrazine..................................