[Federal Register Volume 64, Number 32 (Thursday, February 18, 1999)]
[Proposed Rules]
[Pages 8043-8048]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-3993]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 82
[FRL-6301-8]
RIN 2060-AG12
Protection of Stratospheric Ozone; Listing of Substitutes for
Ozone-Depleting Substances
AGENCY: Environmental Protection Agency.
ACTION: Request for data and advance notice of proposed rulemaking.
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SUMMARY: This action requests comments and information on n-propyl
bromide (nPB) under the U.S. Environmental Protection Agency's (EPA)
Significant New Alternatives Policy (SNAP) program. SNAP implements
section 612 of the amended Clean Air Act of 1990 (CAAA), which requires
EPA to evaluate substitutes for ozone depleting substances (ODSs) to
reduce overall risk to human health and the environment. Through these
evaluations, SNAP generates lists of acceptable and unacceptable
substitutes for each of the major industrial use sectors. The intended
effect of the SNAP program is to expedite movement away from ozone
depleting compounds while avoiding a shift into substitutes posing
other environmental or health problems.
Through this Advance Notice of Proposed Rulemaking (ANPR), the
Agency hopes to receive information as part of the development of
effective regulatory options on the listing of nPB as acceptable or
unacceptable for the various submitted end-uses under SNAP. This action
notifies the public of the availability of information regarding nPB
and the Agency hopes that this action will provide the public an
opportunity to provide input at an early stage in the decision-making
process.
This notice does not constitute a final, or even preliminary,
decision by the Agency. Based on information collected as part of this
ANPR, EPA intends to propose a future determination regarding the
acceptability or unacceptability of nPB as a substitute for class I and
class II ozone depleting substances and, if acceptable, an occupational
exposure limit (OEL) for nPB. This limit would be designed to protect
worker safety until the Occupational Safety and Health Administration
(OSHA) sets its own standards under Public Law 91-596. However, until a
final determination is made, users of nPB should exercise caution in
the manufacture, handling, and disposal of this chemical.
EPA has received petitions under CAAA Section 612(d) to add nPB to
the list of acceptable alternatives for class I and class II ozone
depleting substances in the solvent sector for general metals,
precision, and electronics cleaning, as well as in aerosol and adhesive
applications.
DATES: Written comments on data provided in response to this notice
must be submitted by April 19, 1999.
ADDRESSES: Comments on and materials supporting this advanced notice
are collected in Air Docket # A-92-13, U.S. Environmental Protection
Agency, 401
[[Page 8044]]
M Street, S.W., Room M-1500, Washington, D.C., 20460. The docket is
located at the address above in room M-1500, First Floor, Waterside
Mall. The materials may be inspected from 8 am until 4 pm Monday
through Friday. A reasonable fee may be charged by EPA for copying
docket materials.
FOR FURTHER INFORMATION CONTACT: The Stratospheric Ozone Hotline at
(800)-296-1996 or Melissa Payne at (202) 564-9738 or fax (202) 565-
2096, Analysis and Review Branch, Stratospheric Protection Division,
Mail Code 6205J, Washington, D.C. 20460. Overnight or courier
deliveries should be sent to our 501 3rd Street, N.W., Washington, DC,
20001 location.
SUPPLEMENTARY INFORMATION:
This action is divided into four sections:
I. Section 612 Program
A. Statutory Requirements
B. Regulatory History
II. Listing of Substitutes
III. Information Needs
A. Objective
B. Ozone Depletion Potential
C. Toxicity
D. Potential Use
IV. Regulatory Options
V. References
I. Section 612 Program
A. Statutory Requirements
Section 612 of the Clean Air Act authorizes EPA to develop a
program for evaluating alternatives to ozone-depleting substances. This
program is referred to as the Significant New Alternatives Policy
(SNAP) program. Section 612(c) requires EPA to publish a list of the
substitutes unacceptable for specific uses and a corresponding list of
acceptable alternatives for specific uses. Section 612(d) grants the
right to any person to petition EPA to add a substitute to or delete a
substitute from the lists published in accordance with section 612(c).
B. Regulatory History
On March 18, 1994, EPA published the Final Rulemaking (59 FR 13044)
which described the process for administering the SNAP program and
issued EPA's first acceptability and unacceptability lists for
substitutes in the major industrial use sectors. These sectors include:
refrigeration and air conditioning; foam blowing; solvent cleaning;
fire suppression and explosion protection; sterilants; aerosols;
adhesives, coatings and inks; and tobacco expansion. These sectors
comprise the principal industrial sectors that historically consume
large volumes of ozone-depleting compounds.
The Agency defines a ``substitute'' as any chemical, product
substitute, or alternative manufacturing process, whether existing or
new, that could replace a class I or class II substance. Anyone who
produces a substitute must provide the Agency with health and safety
studies on the substitute at least 90 days before introducing it into
interstate commerce for significant new use as an alternative. This
requirement applies to chemical manufacturers, but may include
importers, formulators or end-users when they are responsible for
introducing a substitute into commerce.
II. Listing of Substitutes
To develop the lists of unacceptable and acceptable substitutes,
EPA conducts screens of health and environmental risks posed by various
substitutes for ozone-depleting compounds in each use sector. The
outcome of these risk screens can be found in the public docket, as
described above in the Addresses portion of this document.
Under section 612, the Agency has considerable discretion in the
risk management decisions it can make in SNAP. The Agency has
identified five possible decision categories: acceptable; acceptable
subject to use conditions; acceptable subject to narrowed use limits;
unacceptable; and pending. Fully acceptable substitutes, i.e., those
with no restrictions, can be used for all applications within the
relevant sector end-use. Conversely, it is illegal to replace an ODS
with a substitute listed by SNAP as unacceptable. A pending listing
represents substitutes for which the Agency has not received complete
data or has not completed its review of the data.
After reviewing a substitute, the Agency may make a determination
that a substitute is acceptable only if certain conditions of use are
met to minimize risks to human health and the environment. Such
substitutes are placed on the ``acceptable, subject to use,
conditions'' lists. Use of such substitutes in ways that are
inconsistent with such use conditions renders these substitutes
unacceptable and subjects the user to enforcement for violation of
section 612 of the Clean Air Act.
Even though the Agency can restrict the use of a substitute based
on the potential for adverse effects, it may be necessary to permit a
narrowed range of use within a sector end-use because of the lack of
alternatives for specialized applications. Users intending to adopt a
substitute acceptable with narrowed use limits must ascertain that
other acceptable alternatives are not technically feasible. Companies
must document the results of their evaluation, and retain the results
on file for the purpose of demonstrating compliance. This documentation
shall include descriptions of substitutes examined and rejected,
processes or products in which the substitute is needed, reason for
rejection of other alternatives, e.g., performance, technical or safety
standards, and the anticipated date other substitutes will be available
and projected time for switching to other available substitutes. Use of
such substitutes in applications and end-uses which are not specified
as acceptable in the narrowed use limit renders these substitutes
unacceptable.
III. Information Needs
A. Objective
As noted above, the purpose of today's notice is to elicit the
voluntary submission of information on nPB as a substitute for class I
and class II substances. Listed below are the specific areas of
information that will be most useful to the Agency in completing the
risk characterizations needed to make regulatory decisions. However,
any available data pertaining to nPB will be considered by the Agency.
Data submitted in response to this request can be designated as
confidential business information (CBI) under 40 CFR, part 2, subpart
B.
EPA has been reviewing the data available on nPB with regard to its
toxicity and its ozone depletion potential. In order to ascertain the
extent of potential environmental implications associated with the use
of this chemical, the Agency is also interested in estimates of nPB
production and ultimate use in various applications. Based on the
assessment to date, the Agency believes that additional information in
all of these areas is needed before regulatory decisions can be
formulated. This notice is to inform the public of the information gaps
and to make publicly available the data to which the Agency already has
access. In this light, EPA is establishing a docket with all available
information on the environmental and health risks associated with nPB,
and is asking for comments and data that can supplement this
information. EPA is seeking public comment regarding nPB in the
following areas where EPA believes that either significant
uncertainties exist in the available data or the data are incomplete.
These areas are critical to EPA's decision-making on the acceptability
or unacceptability of nPB.
[[Page 8045]]
B. Ozone Depletion Potential
The ozone depletion potential (ODP) of a chemical compound provides
a relative measure of the expected impact on stratospheric ozone per
unit mass of the emission of the compound, as compared to that expected
from the same mass emission of CFC-11 integrated over time. ODP is a
benchmark that has been used by the Parties to the Montreal Protocol to
characterize the relative risks associated with the various ozone-
depleting compounds subject to the Protocol's requirements. Under the
auspices of the United Nations Environment Programme, every four years
the world's leading experts in the atmospheric sciences publish a
scientific assessment, relied upon by the Parties to the Montreal
Protocol for future decisions regarding protection of the stratospheric
ozone layer. These assessments evaluate the impacts of ozone depleting
substances on stratospheric ozone concentrations using ODP. Prior
analyses of ODP conducted by these experts, as well as by others in the
field of atmospheric chemistry, have traditionally focused on compounds
with relatively long atmospheric lifetimes (e.g., three months or
longer) (WMO, 1994).
Recently, EPA has been called upon to review compounds of much
shorter lifetimes, such as nPB, which has an estimated atmospheric
lifetime of only 11 days. Estimates of ODP for nPB based on the current
models lie within the range of 0.006-0.027 (Wuebbles et al., 1997 and
1998). The two-dimensional (2-D) and other models currently used to
estimate the relative effects of long-lived compounds on stratospheric
ozone, however, may not be as useful in measuring effects associated
with compounds with very short atmospheric lifetimes.
Chemicals previously evaluated for ODP have atmospheric lifetimes
sufficiently long to be well-mixed in the troposphere, and 2-D models
have been adequate tools for ODP estimation. Short-lived substances
(i.e., compounds with atmospheric lifetimes shorter than three months)
such as nPB can either reach the stratosphere or, unlike long-lived
compounds, break down in the troposphere. Thus, the amount of bromine
that would be available to affect stratospheric ozone greatly depends
on the complex effects of transport and chemical processes in the
troposphere. Two-dimensional modeling is not designed to accurately
account for variations in chemical concentration at different latitudes
or for atmospheric transport of short-lived compounds. As a result,
there are questions about the adequacy of the ODPs determined with
these models for short-lived chemicals like nPB. Since current models
may not accurately evaluate impacts of these short-lived compounds, EPA
is concerned that it may be difficult to meaningfully compare them to
the longer-lived compounds already controlled.
EPA is presently developing a process to more accurately determine
ODPs for short-lived compounds. Independent atmospheric scientists are
also in the process of refining current atmospheric models for this
same purpose. The models are expected to examine a variety of questions
related to convective transport rates at different latitudes, and the
relative importance of transient versus steady-state effects. EPA
expects this work to increase the accuracy of the ODP estimate for nPB,
as well as for other short-lived compounds, and the Agency anticipates
that these models will produce preliminary results within the next
year. In addition, the Agency is interested in receiving from the
public any other information pertaining to the atmospheric effects and
ozone depletion potential of short-lived atmospheric chemicals (shorter
than three months), and any additional information on the ozone
depletion potential of nPB, specifically. EPA will make any new
information accessible to the public as it becomes available by placing
it in the docket identified in the Addresses section of this document,
and if appropriate, issue a notice of data availability in the Federal
Register to insure that the public is aware of any new information.
C. Toxicity
Information on the toxicity of nPB was submitted to the Agency as
part of the requirements of the SNAP program. Data from the submitters
included the results of newly performed 28-day and 90-day repeated dose
studies, both of which included a functional observation battery. A
consortium of companies interested in nPB was formed after the initial
data were submitted under the SNAP program. Other studies, not
previously available to the public, were also submitted by a company
that is not part of the consortium. Additional studies were available
from the published scientific journals. A list of the studies received,
evaluated, and placed in the docket is appended in Section VI.
EPA reviewed the literature to evaluate the potential metabolites
of nPB and their expected toxicity following inhalation exposure. A
structure-activity relationship analysis for potential carcinogenicity
was part of this evaluation. The pharmacokinetics of nPB and its
metabolites were also examined, as well as reports of other studies
performed under non-guideline protocols. Data on structural analogues
of nPB, such as 2-propyl bromide, were also reviewed. This information,
and the reports of the acute (less than 14-day) studies, 28-day and 90-
day inhalation studies can be used to estimate a tentative exposure
limit for the use of nPB in industrial settings. The ``no observed
adverse effect level'' (NOAEL) for liver effects in the 90-day study of
2000 milligrams per cubic meter (mg/m\3\), or 400 parts per million
(ppm), is a possible basis for setting an industrial exposure guideline
(ICF 1998k). Based on this NOAEL, EPA's preliminary estimate of an
exposure guideline is in the range of 50-100 ppm as an 8-hour time
weighted average. Using the NOAEL for effects on sperm counts and
motility from the Ichihara et al. (1998) study would result in a
preliminary, estimated guideline of 93 ppm, suggesting that a range
from 50-100 ppm would be protective of both liver and testicular
effects. (This limit would be designed to protect worker safety until
the Occupational Safety and Health Administration (OSHA) sets its own
standards under P.L. 91-596. The existence of an EPA standard in no way
bars OSHA from standard-setting under OSHA authorities as defined in
P.L. 91-596.)
EPA also examined the potential uses of nPB in the solvent,
aerosol, and adhesives, coatings and inks sectors and received
additional personal monitoring data for these sectors. Preliminary
consideration of the available personal monitoring data (Smith, 1998)
during solvent, adhesive and aerosol usage indicates that nPB exposures
can generally be kept within the range of 50-100 ppm, although some of
the exposure measurements exceeded this range.
At this time, EPA cannot recommend a firm exposure limit because of
identified areas of uncertainty. The fact that reproductive system
effects have been observed in both rats and humans for the similar
compound, 2-propyl bromide, as well as the report of oligospermia in
rats exposed to nPB, raises concern that insufficient testing has been
completed to fully evaluate these significant endpoints. The industry
consortium has responded to these concerns by initiating studies to
test the developmental and reproductive system effects of nPB. Results
from these studies will not be available for another year.
[[Page 8046]]
Finally, EPA is aware that an isomer of nPB, 2-bromo-propane (2BP;
also known as iso-propyl bromide), can be present as a contaminant in
nPB formulations. Occupational exposure to 2BP has been associated with
anemia and reproductive toxicity (Kim et al., 1996). Reproductive and
hematopoietic effects of 2BP have also been demonstrated in animal
studies (Takeuchi et al., 1997; Ichihara et al., 1996, 1997; Kamijima
et al., 1997a,b). Should nPB be listed as acceptable under SNAP, the
Agency would consider establishing maximum concentration limits for 2BP
in applications involving nPB.
EPA is presenting and making publicly available the information it
has received so that interested parties may evaluate these data for
themselves and use it as guidance if they choose to use nPB until a
proposal and final rule are in place. EPA is also interested in
receiving additional information on human health and toxicological
risks associated with exposure to nPB. As EPA receives new data, they
will be added to the docket, along with notice of data availability in
the Federal Register, as appropriate.
D. Potential Use
EPA is requesting information on the anticipated uses for nPB, the
extent of its use in the different sectors (aerosols, solvents,
adhesives, coatings, and inks), as well as estimated market potential.
The Agency is also requesting information on the relative effectiveness
of nPB versus the chemicals it would potentially replace, and the
relative quantities of nPB that would be needed in various sectors
compared to other chemicals that it would potentially replace. This
information will provide the Agency information needed to assess
potential environmental effects associated with use of nPB.
IV. Regulatory Options
EPA believes that notice-and-comment rulemaking is required to
place any alternative on the list of prohibited substitutes, to list a
substitute as acceptable only under certain use conditions or narrowed
use limits, or to remove an alternative from either the list of
prohibited or acceptable substitutes.
EPA does not believe that rulemaking procedures are required to
list alternatives as acceptable with no limitations. Such listings do
not impose any sanction, nor do they remove any prior license to use a
substitute. Consequently, EPA adds substitutes to the list of
acceptable alternatives without first requesting comment on new
listings. Updates to the acceptable and pending lists are published as
separate Notices of Acceptability in the Federal Register.
V. References
Barnsely, E. 1966. The formation of 2-hydroxypropylmercapturic acid
from 1-halogenpropanes in the rat. Biochem J 100:362-372.
Barnsely, E; Grenby, T; Young, L. 1966. Biochemical Studies of Toxic
Agents: the metabolism of 1- and 2-bromopropane in rats. Biochem J
100:282-288.
Bors, W; Michel, C; Dalke, C; Stettmaier, K; Saran, M; Andrae, U.
1993. Radical intermediates during the oxidation of nitropropanes.
The formation of NO2 from 2-nitropropane, its reactivity
with nucleosides, and implications for the genotoxicity of 2-
nitropropane. Chemical Research in Toxicology 6:302-309.
ClinTrials. 1997a. A 28-Day Inhalation Study of a Vapor-Formulation
of ALBTA1 in the Albino Rat. Report No. 91189. Prepared by
ClinTrials BioResearch Laboratories, Ltd., Senneville, Quebec,
Canada. May 15, 1997. Sponsored by Albemarle Corporation, Baton
Rouge, LA.
ClinTrials. 1997b. ALBTA1: A 13-Week Inhalation Study of a Vapor
Formulation of ALBTA1 in the Albino Rat. Report No. 91190. Prepared
by ClinTrials BioResearch Laboratories, Ltd., Senneville, Quebec,
Canada. February 28, 1997. Sponsored by Albemarle Corporation, Baton
Rouge, LA.
Cunningham, M; Matthews, H. 1991. Relationship of
hepatocarcinogenicity and hepatocellular proliferation induced by
mutagenic noncarcinogens vs. carcinogens, II. 1- vs. 2-nitropropane.
Toxicology and Applied Pharmacology 110:505-513.
Elf Atochem S.A. 1993. Acute Oral Toxicity in Rats. N-Propyl
Bromide. Study No. 10611 Tar. Study Director, Jack Clouzeau. Study
performed by Centre International de Toxicologie, Miserey, France.
November 3, 1993.
Elf Atochem S.A. 1994. Ames test--reverse mutation assay on
Salmonella typhimurium. n-Propyl Bromide. HIS1005/1005A. Study
performed by Sanofi Recherche, Service de Toxicologie.
Elf Atochem S.A. 1995a. Micronucleus Test by Intraperitoneal Route
in Mice. N-Propyl Bromide. Study No. 12122 MAS. Study Director,
Brigitte Molinier. Study performed by Centre International de
Toxicologie, Miserey, France. September 6, 1995.
Elf Atochem S.A. 1995b. Acute Dermal Toxicity in Rats. N-Propyl
Bromide. Study No. 13113 Tar. Study Director, Stephane de Jouffrey.
Study performed by Centre International de Toxicologie, Miserey,
France. September 26, 1995.
Elf Atochem S.A. 1995c. Skin Sensitization Test in Guinea-Pigs
(Maximization method of Magnusson B, and Kligman, A.M.). N-Propyl
Bromide. Study No. 12094 TSG. Study Director, Stephane de Jouffrey.
Study performed by Centre International de Toxicologie, Miserey,
France. June 30, 1995.
Elf Atochem S.A. 1996. Amendment to Protocol. n-Propyl Bromide.
Study No. 13293 MLY. Amendment No. 01. Study Director, Brigitte
Molinier. January 29, 1996.
Elf Atochem S.A. 1997a. Study of Acute Toxicity on n-Propyl Bromide
Administered to Rats by Vapour Inhalation. Determination of the 50%
Lethal Concentration. L.E.T.E. Study Number 95122. Study performed
by Laboratoire d'Etudes de Toxicologie Experimentale.
Elf Atochem. 1997b. Safety Data Sheet for N-Propyl Bromide. Elf
Atochem, Paris, France, 1997.
Elf Atochem. 1997c. Toxicity Data Sheet for N-Propyl Bromide. Elf
Atochem, Department de Toxicologie Industrielle, France, 1997.
Fiala, E.; Czerniak, R.; Castonguay, A.; Conaway, C.; Rivenson, A.
1987. Assay of 1-nitropropane, 2-nitropropane, 1-azoxypropane and 2-
azoxypropane for carcinogenicity by gavage in Sprague-Dawley rats.
Carcinogenesis 8(12):1947-1949.
George, E; Burlinson, B; Gatehouse, D. 1989. Genotoxicity of 1-and
2-nitropropane in the rat. Carcinogenesis 10(12):2239-2334.
Goggelmann, W; Bauchinger, M; Kulka, U; Schmid, E. 1988.
Genotoxicity of 2-nitropropane and 1-nitropropane in Salmonella
typhimurium and human lymphocytes. Mutagenesis 3(2):137-140.
Griffin, T; Stein, A; Coulston, F. 1982. Inhalation exposure of rats
to vapors of 1-nitropropane at 100 ppm. Ecotoxicology and
Environmental Safety 1982, 6, 268-282.
Haas-Jobelius, M; Coulston, F; Korte, F. 1992. Effects of short-term
inhalation exposure to 1-nitropropane and 2-nitropropane on rat
liver enzymes. Ecotoxicology and Environmental Safety 23:253-259.
Haseman, J; Lockhart, A. 1994. The relationship between use of the
maximum tolerated dose and study sensitivity for detecting rodent
carcinogenicity. Fundamentals of Applied Toxicology 22:382-391.
ICF. 1995a. ``Propyl Bromide.'' Memorandum prepared by ICF
Incorporated, Washington, DC, for EPA, under Contract No. 68-D5-
0147, Work Assignment No. 0-13 (October 17, 1995)
ICF. 1996a. ``1-Bromopropane ODP Estimate.'' Memorandum prepared by
ICF Incorporated, Washington, DC, for EPA, under Contract No. 68-D5-
0147, Work Assignment No. 0-13 (January 16, 1996).
[[Page 8047]]
ICF. 1996b. ``Estimated ODPs for Brominated Compounds.'' Memorandum
prepared by ICF Incorporated, Washington, DC, for EPA, under
Contract No. 68-D5-0147, Work Assignment No. 1-11 (October 2, 1996).
ICF. 1997a. ``Review of ALBTA1 (1-Bromopropane) Toxicity Study.''
Memorandum prepared by ICF Incorporated, Washington, DC, for EPA
under Contract No. 68-D5-0147, Work Assignment No. 1-11 (April 1,
1997).
ICF. 1997e. ``Comments on Report `Acceptable Industrial Exposure
Limit for N-Propyl-Bromide'.'' Memorandum prepared by Dr. Elizabeth
Weisburger under subcontract with ICF Incorporated, Washington, DC,
for EPA, under Contract No. 68-D5-0147, Work Assignment No. 1-11
(July 16, 1997).
ICF. 1998c. ``Review of Japanese Study on 1-Bromopropane and 2-
Bromopropane.'' Memorandum prepared by ICF Incorporated, Washington,
DC, for EPA, under Contract No. 68-D5-0147, Work Assignment No. 2-09
(February 16, 1998).
ICF. 1998e. ``Estimating Total Adjusted Chlorine Loading Impact of
N-Propyl Bromide.'' Memorandum prepared by ICF Incorporated,
Washington, DC, for EPA, under Contract No. 68-D5-0147, Work
Assignment No. 2-08 (April 10, 1998).
ICF. 1998h. ``Preliminary Exposure Assessment for N-Propyl-
Bromide.'' Memorandum prepared by ICF Incorporated, Washington, DC,
for EPA, under Contract No. 68-D5-0147, Work Assignment No. 2-06
(April 30, 1998).
ICF. 1998k. ``Acceptable Industrial Exposure Limit for N-Propyl-
Bromide.'' Memorandum prepared by ICF Incorporated, Washington, DC,
for EPA, under Contract No. 68-D5-0147, Work Assignment No. 2-09
(September 24, 1998).
Ichihara G, Asaeda N, Kumazawa T, Tagawa Y, Kamiuima M, Yu X, Kondo
H, Nakajima T, Kitoh J, Yu IJ, Moon YH, Hisanaga N, Takeuchi Y.
1996. Testicular toxicity of 2-bromopropane. J Occup Health 38:205-
206.
Ichihara G, Asaeda N, Kumazawa T, et al. 1997. Testicular and
hematopoietic toxicity of 2-bromopropane, a substitute for ozone
layer-depleting chlorofluorocarbons. J Occup Health 39:57-63.
Ichihara M, Takeuchi Y, Shibata E, Kitoh J, et al. 1998.
Neurotoxicity of 1-Bromopropane. Translated by Albemarle
Corporation.
Jones, A; Walsh, D. 1979. The oxidative metabolism of 1-bromopropane
in the rat. Xenobiotica 9(12):763-772.
Kamijima M, Ichihara G, Yu X, et al. 1997a. Disruption in ovarian
cyclicity due to 2-bromopropane in the rat. J Occup Health 39:3-4.
Kamijima M, Ichihara G, Kitoh J, et al. 1997b. Ovarian toxicity of
2-bromopropane in the nonpregnant female rat. J Occup Health 39:144-
149.
Khan, S; O'Brien, P. 1991. 1-bromoalkanes as new potent nontoxic
glutathione depletors in isolated rat hepatocytes. Biochemical and
Biophysical Research Communications 179(1):436-441.
Kim, HY; Chung, YH; Yi, KH; Kim, JG; Yu, IJ. 1996. LC50
of 2-bromopropane. Industrial Health 34:403-407.
Kim, Y; Jung, K; Hwang, T; Jung, G; Kim, H; Park, J; Kim, J; Park,
J; Park, D; Park, S; Choi, K; Moon, Y. 1996. Hematopoeitic and
reproductive hazards of Korean electronic workers exposed to
solvents containing 2-bromopropane. Scand J Work Environ Health
22:387-91.
Kliesch, U; Adler, I. 1987. Micronucleus test in bone marrow of mice
treated with 1-nitropropane, 2-nitropropane and cisplatin. Mutation
Research 192:181-184.
Kohl, C; Morgan, P; Gescher, A. 1995. Metabolism of the genotoxicant
2-nitropropane to a nitric oxide species. Chemico-Biological
Interactions 97:175-184.
Lag, M; Omichinski, J; Dybing, E; Nelson, S; Soderlund, E. 1994.
Mutagenic activity of halogenated propanes and propenes: effect of
bromine and chlorine positioning. Chemico-Biological Interactions
93:73-84.
Lag, M; Soderlund, E; Omichinski, J; Brunborg, G; Holme, J; Dahl, J;
Nelson, S; Dybing, E. 1991. Effect of bromine and chlorine
positioning in the induction of renal and testicular toxicity by
halogenated propanes. Chem Res Toxicol 4:528-534.
Lee, Y; Buchanan, B; Klopman, G; Dimayuga, M; Rosenkranz, H. 1996.
The potential of organ specific toxicity for predicting rodent
carcinogenicity. Mutation Research 358:37-62.
Linhart, I; Gescher, A; Goodwin, B. 1991. Investigation of the
chemical basis of nitroalkane toxicity: tautomerism and
decomposition of propane 1-and 2-nitronate under physiological
conditions. Chemico-Biological Interactions 80:187-201.
Loveday, K; Lugo, M; Resnick, M; Anderson, B; Zeiger, E. 1989.
Chromosome aberration and sister chromatid exchange tests in Chinese
hamster ovary cells in vitro: II. results with 20 chemicals.
Environmental and Molecular Mutagenesis 13:60-94.
Maeng, SH; Yu, IJ. 1997. Mutagenicity of 2-bromopropane. Industrial
Health 35:87-95.
Oh B, Kaneko H, Sato A. 1998. Effects of 1-BP to the translation of
beta-amyloid protein in mouse brain comparison between young mouse
and adult mouse. Translated by Albemarle Corporation.
Ong, J; Kerr, D; Lacey, G; Curtis, D; Hughes, R; Prager, R. 1994.
Differing actions of nitropropane analogs of GABA and baclofen in
central and peripheral preparations. European Journal of
Pharmacology 264:49-54.
Perocco, P; Bolognesi, S; Alberghini, W. 1983. Toxic activity of
seventeen industrial solvents and halogenated compounds on human
lymphocytes cultured in vitro. Toxicology Letters 16:69-75.
Ratpan, F; Plaumann, H. 1988. Mutagenicity of halogenated propanes
and their methylated derivatives. Environmental and Molecular
Mutagenesis 12:253-259.
Roscher, E; Kyriakoula Z-S; Andrae, U. 1990. Involvement of
different pathways in the genotoxicity of nitropropanes in cultured
mammalian cells. Mutagenesis 5(4):375-380.
Rosenkranz, H; Klopman, G. 1990. Prediction of the carcinogenicity
in rodents of chemicals currently being tested by the US National
Toxicology Program: structure-activity correlations. Mutagenesis
5(5):425-432.
Rosenkranz, H; Klopman, G. 1993. Structural evidence for a dichotomy
in rodent carcinogenesis: Involvement of genetic and cellular
toxicity. Mutation Research 303:83-89.
Saito-Suzuki, R; Teramoto, S; Shirasu, Y. 1982. Dominant lethal
studies in rats with 1,2-dibromo-3-chloropropane and its
structurally related compounds. Mutation Research 101:321-327.
Smith, R.L. 1997. ``Significance of the Japanese presentation on 1-
BP and 2-BP.'' Fax transmission from Robert Smith, Albemarle
Corporation to EPA, December 29, 1997.
Smith, R.L. 1998. Assessments of occupational exposure to nPB in
adhesive spray and metal cleaning applications. Written
communications from Robert Smith, Albemarle Corporation to EPA,
March 19 through June 26, 1998.
Sodum, R; Soon Shon, O; Nie, G; Fiala, E. 1994. Activation of the
liver carcinogen 2-nitropropane by aryl sulfotransferase. Chemical
Research in Toxicology 7:344-351.
Takeuchi, Y; Ichihara, G.; Kamijima, M. 1997. A review of toxicity
of 2-bromopropane: mainly on its reproductive toxicity. J. Occup
Health 39:179-191.
World Meteorological Organization. 1994. Scientific Assessment of
Ozone Depletion: 1994. Global Ozone Research and Monitoring Project,
Report No. 37. Geneva, Switzerland; World Meteorological
Organization.
Wuebbles, D.J., A.K. Jain, K.O. Patten, and P.S. Connell. 1997.
``Evaluation of Ozone Depletion Potentials for chlorobromomethane
(CH2ClBr) and 1-bromo-propane
(CH2BrCH2CH2),'' Atmos. Environ.,
32, 107-113.
Wuebbles, D.J., R. Kotamarthi, and K.O. Patten. 1998. ``Updated
Evaluation of Ozone Depletion Potentials for Chlorobromomethane
(CH2ClBr) and 1-bromo-propane
(CH2BrCH2CH2),'' Atmos. Environ.,
in press.
[[Page 8048]]
Dated: February 10, 1999.
Carol M. Browner,
Administrator.
[FR Doc. 99-3993 Filed 2-17-99; 8:45 am]
BILLING CODE 6560-50-P
