[Federal Register Volume 69, Number 85 (Monday, May 3, 2004)]
[Notices]
[Pages 24164-24168]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-9946]
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DEPARTMENT OF HEALTH AND HUMAN SERVICES
Centers for Disease Control and Prevention
Interim Recommendations for Airborne Exposure Limits for Chemical
Warfare Agents H and HD (Sulfur Mustard)
AGENCY: Centers for Disease Control and Prevention (CDC), Public Health
Service, Department of Health and Human Services (HHS).
ACTION: Notice of interim recommendations for airborne exposure limits
for chemical warfare agents H and HD (sulfur mustard).
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SUMMARY: Agents H and HD are stored and are being destroyed by the
Department of Defense (DoD). Public Law 99-145 (50 U.S.C. 1521)
mandates that the Secretary of Defense carry out the destruction of the
United States' stockpile of lethal chemical agents and munitions.
Public Law 91-121 and Public Law 91-441 (50 U.S.C. 1512) mandate that,
prior to the disposal of any such agent within the United States, the
Secretary of Defense implement any precautionary measures recommended
by the Secretary of the Department of Health and Human Services (HHS)
to protect the public health. This notice provides CDC's interim
recommendations for worker and general population airborne exposure
limits (AELs) for sulfur mustard. These revised exposure limits replace
CDC's previously recommended AELs originally issued in 1988. These
limits are being issued as interim criteria pending improved
characterization of carcinogenic potential associated with sulfur
mustard.
EFFECTIVE DATE: July 1, 2005. An implementation period is necessary to
allow the DoD to make program adjustments and allow time for changes to
environmental permits as required.
FOR FURTHER INFORMATION CONTACT: Dr. Paul Joe, Chief Medical Officer,
Environmental Public Health Readiness Branch, Division of Emergency and
Environmental Health Services, National Center for Environmental
Health, CDC, 4770 Buford Highway, Mail Stop F-16, Atlanta, Georgia
30341.
SUPPLEMENTARY INFORMATION: On July 22, 2003, CDC published 68 FR 43356,
``Proposed Airborne Exposure Limits for Chemical Warfare Agents H, HD,
HT (Sulfur Mustard)'' \1\ seeking public comment. Today's notice
discusses major comments received, describes decisions regarding the
public comments, and provides interim recommendations. CDC received
comments from the U.S. Army, the State of Utah, the State of Colorado,
and one employee union.
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\1\ The toxicity data for agent T are inadequate for setting
exposure limits. The very low vapor pressure for agent T precludes
it as a vapor under normal ambient conditions. For sulfur mustard
and T mixtures, air monitoring for sulfur mustard alone should be
sufficient under most circumstances to prevent airborne exposure to
it.
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The comments fell into the following general categories: risk
management assumptions used in CDC's deliberations, selection of
uncertainty factors, determination of the cancer potency factor for the
mustard AELs, and practical concerns of conducting air monitoring at
the lower exposure limits. The key comments potentially impacting CDC's
recommendations are summarized and discussed below:
1. One reviewer remarked that the 5-minute ceiling (Ceiling-5M) may
require too short of an analytical cycle for use with dual-agent air
monitoring instrumentation.
Discussion: The Ceiling-5M was defined to provide a ceiling value
for near-real-time (NRT) corrective action that would protect worker
health in the short term and meet the long-term goal of keeping the
carcinogenicity risk below one in one million. The 8-hour time-weighted
average (TWA) exposure limit recommended by CDC in 1988 was implemented
by the chemical demilitarization program as a ceiling value, monitored
by NRT instruments having a sampling and analysis cycle time of under 5
minutes. CDC's proposal sought to reflect this conservative
implementation of the 1988 criteria.
CDC closely examined the various implicit exposure doses, measured
in terms of concentration multiplied by time of exposure (Ct), for
various potential exposure scenarios. The ceiling-5M was based upon the
analytic cycle times used in the stockpile demilitarization program.
Longer sampling and analytic cycle times, such as those used in the
monitoring programs for chemical agent storage facilities or
nonstockpile program, could be considered in a similar manner, that is,
by evaluating the effect on the Ct by changing duration of potential
exposure with varying instrument cycle times.
CDC examined the implication of applying the ceiling-5M agent
concentration with cycle times greater than 5 minutes. Comments
received from the Army, indicated that the dual agent monitors use
cycle times of up to 10 minutes. Accordingly, CDC reviewed the impact
of using 10- to 15-minute cycle times at the same concentration used
with the ceiling-5M. Both the short-term and long-term health
protection goals were met; that is, the effective dose or Ct associated
at this level and duration are still well under the Ct for the acute
threshold of effects level (referenced in the July 22, 2003, support
document for the proposed sulfur mustard AELs) and the carcinogenicity
risk per episode would be well under one in one million.
The above analysis would suggest that a longer analytic cycle time,
even up to the 15 minutes, associated with the Army's NRT monitoring
definitions, would be acceptable at the
[[Page 24165]]
concentration proposed with the ceiling-5M. However, real-world leaks,
spills, or other unplanned agent releases do not follow a defined
pattern of gradual airborne concentration increase. The first cycle of
a monitoring alarm could be at much higher concentrations than the
ceiling-5M. Consequently, to limit potential agent exposure durations
at higher level exposures, analytic cycle time should be kept as short
as practicable.
The final factor considered in CDC's review of this issue is the
overall risk management implication of modifying the implied cycle time
associated with the ceiling AEL. Clearly, the degree of protectiveness
increases as the cycle time decreases, assuming all other quality
control criteria remain constant. However, if programmatic delays or
extraordinary new personnel protective measures are introduced as
interim measures in the pursuit of more ideal monitoring capabilities,
overall risk could increase to both workers and the public.
In summary, CDC believes that the proposed ceiling-5M was overly
proscriptive and possibly counterproductive. Accordingly, CDC
redesignated this AEL as a 15-minute short-term exposure limit (STEL).
The concentration value, 0.003 mg/m\3\, from the ceiling-5M is
retained. This STEL is to be monitored with NRT technology using the
shortest practicable instrument cycle time. For the maximum 15-minute
duration of the STEL, the Ct is 0.045 mg-min/m\3\.
2. One reviewer remarked that using the proposed general population
limit (GPL) for worker protection could result in excessive false-
positive situations and attendant disruptions wherever significant
interferences might be located.
Discussion: The GPL is a criterion that is set to protect the
general public. Community exposure limits are set lower than worker
limits to reflect wider variation in human susceptibility than that of
the healthy worker population.
CDC premised its proposal to use the new GPL as a worker protection
criterion on two basic considerations. First, because the GPL is
designed to protect the community, it would also be adequate for a
worker population. Second, CDC believed that historic monitoring for
the GPL for demilitarization perimeter monitoring similarly could be
implemented in worker locations to accommodate longer 12-hour shifts.
As discussed in CDC's proposal, the GPL for sulfur mustard was
driven largely by the goal of protecting the public at a cancer risk
level of less than one cancer incidence in a million exposures at the
GPL for 3 continuous years, a risk level that is considered to be
negligible. Three years was chosen for the duration of the potential
exposure at a GPL because it was believed to be the maximum duration of
a campaign where sulfur mustard munitions would be handled and
processed for destruction on a continuing basis. This assumed exposure
scenario is conservative for both the public and workers for a number
of reasons:
No one worker works continuously for 3 years;
actual time at work is probably well under one-third of all available
hours per year when weekends, holidays, and vacations are considered.
Demilitarization plant workers, storage site
workers, non-stockpile site workers, or others who might reasonably be
exposed to chemical agent do not remain stationary at one duty location
for extended periods.
Similarly, the individuals within the general
community would not normally be anticipated to stay at one location
continuously for 3 years.
Varying meteorological conditions would preclude
constant exposure conditions.
With the rigorous active demilitarization site
monitoring and the ongoing routine storage site inspection program,
unplanned releases of chemical agent are unlikely to be sustained for
any significant duration.
CDC assumed exposure at the full GPL in its
carcinogenicity evaluation even though detection at this level would
result in investigation and remedial action. Typically, risk assessment
professionals use some fraction of a ``practical quantification limit''
or detection level.
The above mitigating factors suggest that long-term exposure
scenarios (up to 3 years) used to estimate sulfur mustard
carcinogenicity review overstates the true risk. Accordingly, CDC
recommends retaining the proposed GPL for perimeter monitoring stations
at demilitarization facilities and evaluation of the allowable stack
concentrations.
For worker protection against low-level exposure, CDC now
recommends a separate 8-hour TWA for a worker protection limit (WPL)
rather than applying the GPL as originally proposed. In the earlier
proposal for mustard AELs, CDC investigated the development of a WPL
using the Environmental Protection Agency (EPA) Categorical Regression
(CatReg) method. The value derived from this method is 0.0003 mg/m\3\.
This value is in reasonably close agreement with the U.S. Army Center
for Health Promotion and Preventive Medicine (CHPPM) reference
concentration-derived (RfC) WPL of 0.0004 mg/m\3\ and the Agency for
Toxic Substances and Disease Registry (ATSDR) acute inhalation minimum
risk level (MRL) \2\ of 0.0007 mg/m3 (1,2). CDC believes
that the CHPPM-recommended value for an 8-hour TWA is protective for
noncarcinogenic effects and should be implemented for worker
protection.
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\2\ ATSDR defines an MRL as ``an estimate of daily human
exposure to a substance that is likely to be without appreciable
risk of adverse noncancer health effects over a specified route and
duration of exposure.'' ATSDR also developed an intermediate MRL
(continuous exposure for up to 1 year) for sulfur mustard at a value
of 0.00002 mg/m\3\ that is numerically equivalent to the interim GPL
recommended herein.
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3. The Army noted that, although CDC specified that the proposed
AELs were developed for and based upon agent stockpile demilitarization
practice, other non-stockpile and storage situations existed to which
the AELs would be applied within other Army programs. Illustrations of
a number of such situations and some suggested resolutions were
provided for CDC's consideration.
Discussion: In CDC's proposal, the use of Ct evaluations was
emphasized as an indication of potential acute exposure dose. For
potential applications beyond strict stockpile demilitarization,
adjustments to implementation of AELs might be warranted on the bases
of site-specific or activity-specific conditions. However, any such
potential AEL implementation and adjustment for site-specific
conditions must ensure that the new monitoring action level protects at
the potential exposure dose (Ct) so that the recommended 8-hour WPL is
not exceeded. Also, any NRT monitors should not have action levels set
above the recommended STEL.
4. Two reviewers commented that CDC's selection of the National
Academy of Science (NAS) cancer potency factor (CPF) was inappropriate
because the benzo-a-pyrene (BaP) index value used was based upon oral,
not inhalation, exposure. They also believed that CDC should use the
30-year exposure assumption described in EPA's risk assessment
guidelines.
Discussion: To estimate cancer risk, exposure assumptions and a
numeric estimate of the potency of carcinogenicity of a substance are
necessary. The reviewers believed that CDC should have used a 30-year
duration for such exposure at the lifetime adjusted daily dose. CDC
appreciates the general desirability to be
[[Page 24166]]
consistent with established guidelines in risk assessment, but EPA has
acknowledged in its 1999 Carcinogen Risk Assessment Guidelines (RAG),
that ``in the face of scientific uncertainty, common sense and
reasonable application of assumptions and policies are essential to
avoid unrealistic estimates of risk'' (3). CDC believes that a 30-year,
or even a 10-year, exposure assumption significantly overestimates
potential exposures by one or more orders of magnitude. For example,
members of the general public are highly unlikely to be continually
exposed to sulfur mustard, night and day, for 10 or 30 years.
Similarly, atmospheric stability, wind speed, and direction are not
fixed for years on end. No agent reduction is assumed for environmental
degradations or rainfall that would reduce concentrations. No agent
reduction is assumed for low temperature environmental conditions where
mustard agent would not significantly volatilize. No agent reduction is
assumed for agent dilution beyond the perimeter of a facility. At agent
storage sites, GPL readings are taken daily at the facility perimeter.
Levels of agent approaching GPL should be detected within days, not
years, of occurrence and corrective action would be initiated.
Historically, agent releases to the environment have been episodic; no
indication exists that continuous, long term low-level agent releases
routinely occur.
CDC's examination of the potential cancer risk associated with
proposed AELs considered only incremental potential risk. That is,
historic risk to workers and the public in the vicinity of stockpile
storage facilities was not examined. This was because each site would
have to be considered individually regarding amount, nature and age of
stored mustard items; local spatial, and meteorologic conditions and
their relation to area demographics; and the nature and capabilities of
historic storage facility inspection programs. These site-specific
factors, coupled with a weak quantification of cancer potency (see
discussion below) of sulfur mustard, suggested limited utility in
attempting to quantify such potential risk.
The other major criticism received by CDC regarding carcinogenicity
analysis pertained to the use of the NAS recommended CPF (2000) based
upon sulfur mustard relative potency compared with BaP. The NAS
recommendation was predicated upon oral dosage, not inhalation. CDC
believed that the other published studies used to support attempts at
developing numeric estimates of the CPF for sulfur mustard seriously
lacked merit for this application. Although an averaging estimate
(i.e., geometric mean) for all the CPFs developed might provide a
reasonable estimate, CDC believes that a mathematic manipulation of
questionable numbers in no way ensures that the new number is
appropriate. Furthermore, CDC believes that without a reasonable basis
to suggest the estimates used in the averaging method bracket the true
CPF as applied to humans; CDC should not arbitrarily rely on a number
developed in this manner.
CDC agrees with the reviewers that extrapolation between exposure
routes is undesirable when examining cancer risk. EPA's 1999 Carcinogen
RAG addresses this issue briefly: ``In the absence of contrary data,
the qualitative default assumption is that, if the agent is absorbed by
a route to give an internal dose, it may be carcinogenic by that
route'' (3). Furthermore, EPA states that, ``For screening or hazard
ranking, route-to-route extrapolation may be based on assumed
quantitative comparability as a default, as long as it is reasonable to
assume absorption by compared routes'' (3). In light of CDC's
reluctance to use CPF averaged numbers as described above, and in the
absence of other, better data, CDC recognized that a route-to-route
extrapolation was needed if the carcinogenicity risk through inhalation
was to be examined and consequently based its analysis upon the NAS-
recommended potency value.
CDC believes that the reviewers raise a valid point regarding the
use of the indexed value as done in the Federal Register proposal. The
reasonableness of the assumption that both exposure routes result in
comparable agent absorption is debatable. CDC does not believe strongly
that such an assumption is valid; consequently, CDC is open to further
examination of this issue. CDC does not believe that the CPF geometric
mean offers any demonstrable scientific improvement over the route-to
route extrapolation originally used in CDC's proposal. The reviewers
recommend that a range of inhalation cancer slope factors be described
according to EPA's Carcinogen RAG. CHPPM presented such a range of
factors in the ``Evaluation of Airborne Exposure Limits for Sulfur
Mustard: Occupational and General Population Exposure Criteria,''
November 2000 and can be referred to by the reader for insight into the
variability of postulated risk dependent upon a range the exposure
assumptions and CPFs (1). The CHPPM examination is consistent with
EPA's guidance. CDC must caution the reader, however, that these
numeric estimates are tenuous. Oak Ridge National Laboratory's 1993
discussion of this issue for sulfur mustard carcinogenicity illustrates
CDC's concerns:
``Unfortunately, quantitative human cancer risk estimates are
impractical because the experimental data from animal studies have
three large uncertainties:
Only a few experiments were conducted;
Many were in a mouse strain that exhibited a
high genetic susceptibility to spontaneous pulmonary tumors;
Routes of administration tested and duration of
follow-up observations are not comparable to the human exposures of
concern.'' (4)
In 1991, EPA examined cancer risk estimates that cover the range of
cancer slope factors presented in the CHPPM document. EPA observed,
``Depending on the unknown true shape of the dose-response curve at low
doses, actual risks may be anywhere from this upper bound down to
zero''(5). Similarly, in the 2003 ATSDR Toxicological Profile for
Sulfur Mustard, the inhalation cancer effects discussion states, `` * *
* in no case was the exposure level or duration quantified, and
therefore, these data are inadequate for deriving dose-response
relationships''(2).
CDC recommends that a better characterization of an appropriate
cancer slope factor needs to be conducted to set exposure limits. CDC
is aware of proposed forthcoming animal research by DoD to examine the
chronic impact of long-term exposure to sulfur mustard. CDC encourages
this research and the examination of results for possible insights and
refinement of an estimate of a more accurate CPF.
5. All four reviewers provided opinions regarding the use of
uncertainty factors to derive AELs. One reviewer believed that
rationale was sufficient to reduce the total uncertainty used by the
National Institute for Occupational Safety and Health (NIOSH) to derive
the Immediately Dangerous to Life or Health (IDLH) criterion by a
factor of three, which would result in an increase to a value of 2.0
mg/m3. Another reviewer wanted to lower the IDLH by a factor
of two because of limitations of military studies used to derive the
value. Another reviewer believed strongly that the proposed GPL should
be reduced by at least an additional factor of 10 to reflect
uncertainties not adequately represented by either the CHPPM
examination using the RfC method or the CDC examination using the
CatReg method. Finally, another reviewer believed that CDC's total
uncertainty
[[Page 24167]]
factor of 300 used to derive the GPL was appropriate but recommended
that the uncertainty factor for intrahuman variation be decreased from
10 to 3 and the data quality factor be increased from 3 to 10.
Supporting rationale was provided for all these opinions.
Discussion: Professional judgment is needed in the application of
uncertainty factors. As discussed in CDC's original support document,
considerable deliberation is ongoing regarding the use of uncertainty
factors in risk assessment. No validated or calibrated means exist to
precisely quantify total uncertainty used in deriving AELs. This was
why CDC considered not only at the RfC, CatReg, and carcinogenicity
considerations, but also the risk management aspects of safely managing
sulfur mustard agent as associated with the demilitarization program.
The reviewer who recommended the minimal 10-fold decrease in the
GPL also believed that AELs should be developed independent of risk
management considerations. CDC agrees that ideally developed AELs
should be independent of existing risk management conditions. One could
argue that CDC should ``safe-side'' the AELs by using highest
uncertainty factors recommended by all reviewers and ignore any
recommendations for reduction of uncertainty factors. Except for
compounds exhibiting hormesis, this approach always would be
theoretically safer than using a number derived using uncertainty
factors that are not on the most conservative end of the spectrum of
professional judgment.
CDC's mission is to enhance public and worker health protection for
people associated with or living near chemical agent demilitarization
facilities. CDC believes that real-world risk management must be
factored into its deliberations. Otherwise, CDC could increase or
extend actual risk in the real world to minimize theoretical or
undemonstrated risk. EPA's Carcinogenic RAG noted that, ``While it is
appropriate to err on the side of protection of health and the
environment in the face of scientific uncertainty, common sense and
reasonable application of assumptions and policies are essential to
avoid unrealistic estimates of risk''(3,6). Furthermore, CDC/NIOSH
policy for potential occupational carcinogens states that `` * * *
policy will be the development, whenever possible, of quantitative RELs
(recommended exposure limits) that are based on human and/or animal
data, as well as on the consideration of technological feasibility for
controlling workplace exposures to the REL'' (emphasis added).
Summary and Recommendations
Although CDC received only 4 sets of comments on the proposed
mustard AELs, these reviewers clearly tried diligently to represent
their perspectives and concerns. Three sets of comments focused
primarily upon the process used to develop the proposed AELs, and the
fourth focused primarily on the practical implications of the proposed
values. In addition to the solicited comments described above, CDC had
the original proposal reviewed by other government and professional
health risk assessment personnel. With the exception of one reviewer,
the CDC approach to developing AELs in concert with ongoing risk
management provisions of the chemical demilitarization program was not
questioned.
The examination of the carcinogenicity issue is problematic in that
CDC believes that a numeric estimation of a cancer slope factor for
mustard is not well supported. The CHPPM review of this issue, through
the evaluation of the range of attempts at quantifying upper bound
cancer risk from exposure to sulfur mustard, has been referenced herein
to provide the reader with that perspective; however, CDC cannot say
with confidence that the numeric range of slope factors is likely to
provide a reasonable estimate of the true carcinogenic potency of this
agent.
Because of the uncertainties discussed above, especially the
characterization of cancer potency of sulfur mustard, CDC has decided
to issue its recommended AELs as interim values pending better
understanding of the CPF for this agent. CDC believes that for
noncancer effects, the recommended AELs protect worker and public
health.
Regarding the implied carcinogenicity risk, CDC believes that the
strong risk management provisions, such as engineering and
administrative controls within demilitarization facilities, extensive
low-level air monitoring, and the previously discussed mitigating
factors, minimize cancer risk at the interim AELs.
In summary, CDC recommends the following:
Defer recommending a cancer potency factor until
better data are available.
Redesignate the ceiling-5M value as a 15-minute
STEL, limited to one occurrence per day; CDC encourages shortest
practicable analytic cycle times.
Apply the U.S. Army CHPPM-derived 8-hour WPL for
workplace; retain GPL as proposed for use in protecting the general
public.
Implement the recommended AELs as interim
values, to go into effect on July 1, 2005; values to remain interim
until better cancer potency characterization is available or research
data indicate the need for revision.
Continue to recommend rigorous risk management
analysis and practice as has been associated with the chemical agent
demilitarization program practice.
Given the uncertainty in the risk assessment
regarding cancer potency, reduced exposures to sulfur mustard to the
lowest practicable level.
Table 1 below contains the numeric values for the interim
recommended AELs.
Dated: April 27, 2004.
James D. Seligman,
Associate Director for Program Services, Centers for Disease Control
and Prevention.
Table 1.--CDC Recommended Interim Airborne Exposure Limits*
[All values expressed as mg/m\3\ in air with concentration x time [Ct -- mg-min/m\3\] values in parentheses]
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Short-Term
Sulfur mustard (H, HD General Worker population exposure limit Immediately dangerous to
[dagger]) criteria population limit limit [Dagger] life or health
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Exposure Level................ 0.00002 (0.01)... 0.0004 (0.19).... 0.003 (<=0.04).. 0.7 (<=21).
Averaging Time................ 12 hours......... 8 hours.......... <=15 minutes.... <=30 minutes.
Recommended Monitoring Method. Historic .... Historic or Near-real-time.. Near-real-time.
Near-real-time.
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* Although CDC does not specifically recommend additional reduction factors for statistical assurance of action
at the exposure limit, exposures to sulfur mustard should be minimized given the uncertainties in risk
assessment, particularly as related to characterizing carcinogenic potency.
[[Page 24168]]
[dagger] The toxicity data for agent T is inadequate for setting exposure limits. The very low vapor pressure
for agent T precludes it as a vapor hazard under normal ambient conditions. For sulfur mustard and T mixtures,
air monitoring for sulfur mustard alone should be sufficient under most circumstances to prevent exposure to
T.
[Dagger] To be evaluated with near-real-time instrument using shortest practicable analytic cycle time. No more
than one exposure per work-shift.
The 30-minute period is not meant to imply that workers should stay in the work environment any longer than
necessary; in fact, they should make every effort to exit immediately. IDLH conditions require highly reliable
dermal and respiratory protection.
Historic monitoring typically is used for time-weighted average (TWA) monitoring where the sample analyzed
represents an extended time period, e.g., 8 or 12 hours. Results are not known until laboratory analysis is
completed after the sampling event. AELs using historic monitoring are set at levels at which health effects
are not expected to occur for most workers. Exposures above the WPL-8, but below the STEL, likewise are not
expected to result in significant health effects unless such exposures occur continuously for long periods.
References
1. U.S Army. Evaluation of Airborne Exposure Limits for Sulfur
Mustard: Occupational and General Population Exposure Criteria--47-
EM-3767-00. Aberdeen Proving Ground, MD: U.S. Army Center for Health
Promotion and Preventive Medicine, November 2000.
2. U.S. Department of Health and Human Services: Toxicological
Profile for Sulfur Mustard (Mustard Gas). Atlanta, GA: Agency for
Toxic Substances and Disease Registry, September 2003.
3. U.S. Environmental Protection Agency: Draft Guidelines for
Carcinogen Risk Assessment. Washington, DC: U.S. Environmental
Protection Agency, July 1999; Publication No. NCEA-F-0644.
4. Nicholson W, Watson A. Risk assessment considerations for sulfur
mustard. In: Pechura CM, Rall DP (eds.) Veterans at Risk: The Health
Effects of Mustard Gas and Lewisite, Washington, DC: National
Academy Press, 1993: 390-8.
5. U.S. Environmental Protection Agency: Upper-Bound Quantitative
Cancer Estimate for Populations Adjacent to Sulfur Mustard
Incineration Facilities. Washington, DC: U.S. Environmental
Protection Agency, Office of Research and Development, July 1991,
Publication No. EPA/600/8-91/053.
6. U.S. Environmental Protection Agency: Policy for Risk
Characterization. Memorandum of Carol M. Browner, Washington, DC:
U.S. Environmental Protection Agency, March 21, 1995.
[FR Doc. 04-9946 Filed 4-30-04; 8:45 am]
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