[Federal Register Volume 73, Number 45 (Thursday, March 6, 2008)]
[Notices]
[Pages 12178-12179]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E8-4339]



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DEPARTMENT OF HEALTH AND HUMAN SERVICES

Agency for Toxic Substances and Disease Registry

[ATSDR-238]


Notice of the Revised Priority List of Hazardous Substances That 
Will Be the Subject of Toxicological Profiles

AGENCY: Agency for Toxic Substances and Disease Registry (ATSDR), U.S. 
Department of Health and Human Services (HHS).

ACTION: Notice.

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SUMMARY: The Comprehensive Environmental Response, Compensation, and 
Liability Act of 1980 (CERCLA or Superfund), as amended by the 
Superfund Amendments and Reauthorization Act of 1986 (SARA), requires 
that ATSDR and the Environmental Protection Agency(EPA) prepare a 
Priority List of Hazardous Substances commonly found at facilities on 
the CERCLA National Priority List (NPL). The Priority List of Hazardous 
Substances includes substances that have been determined to be of 
greatest public health concern to persons at or near NPL sites. CERCLA 
as amended also requires that ATSDR and EPA periodically revise the 
Priority List of Hazardous Substances.
    Pursuant to these CERCLA mandates, the agencies announce that based 
on the most recent information available, they have developed and now 
make available a revised CERCLA Priority List of 275 Hazardous 
Substances. Because CERCLA as amended also requires ATSDR to prepare 
and to periodically revise toxicological profiles on hazardous 
substances included in the priority list, each priority list substance 
is a potential toxicological profile subject, as well as a candidate 
for identification of priority data needs.
    In addition to the Priority List of Hazardous Substances, ATSDR has 
developed a Completed Exposure Pathway Site Count Report. This report 
lists the number of sites or events at which ATSDR is involved and 
wherein a substance has been found in a completed exposure pathway 
(CEP). This report is included in the Support Document of the Priority 
List.

ADDRESSES: Requests for a printed copy of the 2007 CERCLA Priority List 
of Hazardous Substances That Will Be The Subject of Toxicological 
Profiles and Support Document, including the CEP report, should include 
the docket control number ATSDR-238, and should be submitted to Ms. 
Nickolette Roney, Division of Toxicology and Environmental Medicine, 
ATSDR, Mail Stop F-32, 1600 Clifton Road, NE., Atlanta, GA 30333. 
Requests must be in writing.
    Electronic Availability: The 2007 Priority List of Hazardous 
Substances and Support Document will be posted on ATSDR's Web site 
located at http://www.atsdr.cdc.gov/clist.html. The CEP Report will 
also be posted at http://www.atsdr.cdc.gov/cep.html. This is an 
informational notice only; no comments are solicited at this time. Any 
comments received will, however, be considered for inclusion in the 
next revision of the list and placed in a publicly accessible docket. 
Therefore, please do not include in comments any confidential business 
information or any other confidential information.

FOR FURTHER INFORMATION CONTACT: Division of Toxicology and 
Environmental Medicine, ATSDR, 1600 Clifton Road NE., Mail Stop F-32, 
Atlanta, GA 30333, telephone 800-232-4636.

SUPPLEMENTARY INFORMATION: CERCLA establishes certain requirements for 
ATSDR and EPA with regard to hazardous substances most commonly found 
at facilities on the CERCLA NPL. Section 104(i)(2)(A) of CERCLA, as 
amended,\1\ requires that ATSDR and EPA prepare a list, in order of 
priority, of at least 100 hazardous substances most commonly found at 
facilities on the NPL and which, in the agencies' sole discretion, pose 
the most significant potential threats to human health (see also 52 FR 
12866, April 17, 1987). CERCLA section 104 (i)(2)(B) \2\ also requires 
the agencies to revise the priority list to include 100 or more 
additional hazardous substances (see also 53 FR 41280, October 20, 
1988), and to include at least 25 additional hazardous substances in 
each of the three successive years following the 1988 revision (see 54 
FR 43619, October 26, 1989; 55 FR 42067, October 17, 1990; and 56 FR 
52166, October 17, 1991).CERCLA section 104(i)(2)(B) further requires 
ATSDR and EPA at least annually to revise the list to include any 
additional hazardous substances that have been determined to pose the 
most significant potential threat to human health.
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    \1\ 42 U.S.C. 9604(i)(2)(A).
    \2\ 42 U.S.C. 9604(i)(2)(B).
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    In 1995, the agencies, recognizing the stability of this listing 
activity, altered the priority list publication schedule (60 FR 16478, 
March 30, 1995). As a result, the priority list is now on a 2-year 
schedule, with annual informal review and revision. Each substance on 
the CERCLA Priority List of Hazardous Substances is also a potential 
subject of an ATSDR-prepared toxicological profile and, subsequently, a 
candidate for the identification of priority data needs.
    The initial priority lists of hazardous substances (1987-1990) were 
based on the most comprehensive and relevant information then 
available. In 1991, with the development of ATSDR's HazDat database, 
more comprehensive sources of information became available on the 
frequency of occurrence and the potential for human exposure to 
substances at NPL sites. Using this updated database, in 1991 a revised 
approach and algorithm for ranking substances was developed. On June 
27, 1991, a notice announcing the intention of ATSDR and EPA to revise 
and rerank the Priority List of Hazardous Substances was published (56 
FR 29485). The 1991 Priority List and revised approach used for its 
compilation was summarized in the ``Revised Priority List of Hazardous 
Substances'' Federal Register notice published October 17, 1991 (56 FR 
52166). The same approach and the same basic algorithm have been used 
in all subsequent listing activities, including 2007. The algorithm 
consists of three criteria, which are combined to result in the total 
score. The three criteria are
     Frequency of occurrence at NPL sites;
     Toxicity; and
     Potential for human exposure.
    Because HazDat is a dynamic database in which data collection is 
ongoing, additional information from the HazDat database became 
available for the 2007 listing activity. Since the development of the 
2005 Priority List of Hazardous Substances, this additional information 
has been entered into HazDat. The site-specific information from HazDat 
used in the listing activity has been collected from ATSDR public 
health assessments and from site-file data packages used to develop the 
public health assessments. The new information may include more recent 
NPL frequency-of-occurrence data, additional concentration data, and 
more information on exposure to substances at NPL sites. Using these 
additional data, one substance has been replaced on the list of 275 
substances since the 2005 publication; the replacement substance was 
previously under consideration. Changes in the order of substances 
appearing on the CERCLA Priority List of Hazardous Substances will be 
reflected in program activities that rely on the list for future 
direction.

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    The 2007 Priority List of Hazardous Substances contains, based on 
CERCLA Sec.  104(i)(2)(A) \3\ criteria, 275 substances that represent 
the greatest concern to public health. Using the current algorithm, a 
total of 859 candidate substances have been analyzed and ranked. Of 
these candidates, the 275 substances on the priority list may in the 
future become subjects of toxicological profiles.
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    \3\ 42 U.S.C. 9604(i)(2)(A).
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    In 2 years ATSDR intends to publish the next revised list of 
hazardous substances, with an informal review and revision performed in 
1 year. These revisions will reflect changes and improvements in data 
collection and in availability. Additional information on the existing 
methodology used in the development of the CERCLA Priority List of 
Hazardous Substances can be found in the List Support Document and in 
the above-referenced Federal Register notices.
    In addition to the revised priority list, ATSDR is also releasing a 
Completed Exposure Pathway Site Count Report. A completed exposure 
pathway (CEP) links a contaminant source to a receptor population. The 
CEP ranking is similar to a subcomponent of the listing algorithm's 
potential-for-human-exposure component. The CEP ranking is based on a 
site frequency count and thus lists the number of sites at which a 
substance has been found in a CEP. ATSDR's HazDat database contains 
this information, which is derived from ATSDR public health assessments 
and from health consultations. The CEP report therefore focuses on 
documented exposure, and lists hazardous substances according to 
exposure frequency. Because exposure to hazardous substances is a 
matter of concern, ATSDR publishes this CEP report together with the 
CERCLA Priority List of Hazardous Substances.
    The substances in the CEP report are similar to those in the CERCLA 
Priority List of Hazardous Substances. Substances are listed in the CEP 
report because they are frequently found in completed exposure 
pathways. Some of these substances, however, have a very low toxicity 
(e.g., sodium) and as a result are not included in the CERCLA Priority 
List. As stated, given that the CERCLA Priority List uses toxicity, 
frequency of occurrence, and potential for human exposure to determine 
its priority substances, other low-toxicity substances will not appear 
on the CERCLA Priority List and, consequently, will not become subjects 
of toxicological profiles. In addition, because CERCLA mandates the 
preparation of the Priority List, that list only incorporates data from 
CERCLA NPL sites. The CEP report, on the other hand, uses data from all 
ATSDR-activity sites at which a CEP has been detected.

Ken Rose,
Associate Director, Office of Policy, Planning and Evaluation, National 
Center for Environmental Health/Agency for Toxic Substances and Disease 
Registry.
 [FR Doc. E8-4339 Filed 3-5-08; 8:45 am]
BILLING CODE 4163-70-P