[Federal Register Volume 62, Number 107 (Wednesday, June 4, 1997)]
[Notices]
[Pages 30580-30585]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-14578]
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ENVIRONMENTAL PROTECTION AGENCY
[OPPTS-41048; FRL-5718-3]
Fortieth Report of the TSCA Interagency Testing Committee to the
Administrator; Receipt of Report and Request for Comments
AGENCY: Environmental Protection Agency (EPA).
ACTION: Notice.
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SUMMARY: The TSCA Interagency Testing Committee (ITC), established
under section 4(e) of the Toxic Substances Control Act (TSCA),
transmitted its Fortieth Report to the Administrator of the EPA on
April 28, 1997. In the Fortieth Report, which is included with this
notice, the ITC revised the TSCA section 4(e) Priority Testing List by
removing two isocyanates that were recommended in the 26th Report, one
high production volume chemical, trichloromethane sulfenyl chloride
that was recommended in the 36th Report and 2,4,6-tribromophenol that
was recommended in the 39th Report. The ITC is also proposing
procedures for chemical trade associations and producers, importers,
processors, and users of future ITC-recommended chemicals to
voluntarily provide data needed by U.S. Government organizations
represented on the ITC and thereby reduce the need for the EPA to
promulgate TSCA section 8 rules for these chemicals.
There are no designated or recommended with intent-to-designate
chemicals or chemical groups in the Fortieth Report. EPA invites
interested persons to submit written comments on the Report.
DATES: Written comments on the Fortieth ITC Report should be received
by July 7, 1997.
ADDRESSES: Comments on the Fortieth Report should be submitted to both
the ITC and the TSCA Docket. Send one copy of written comments to: John
D. Walker, ITC Executive Director (7401), U.S. Environmental Protection
Agency, 401 M St., SW., Washington, DC 20460. Send six copies of
written comments to: Document Control Office, Rm. ET-G-099, Office of
Pollution Prevention and Toxics (7407), Environmental Protection
Agency, 401 M St., SW., Washington, DC 20460. All submissions should
bear the document control number OPPTS-41048.
Comments may also be submitted electronically by sending electronic
mail (e-mail) to the ITC ([email protected]) or the EPA
([email protected]). Electronic comments are preferred by the ITC.
Electronic comments must be submitted as an ASCII file avoiding the use
of special characters and any form of security encryption. Comments
will also be accepted on disks in WordPerfect 5.1/6.1 file format or
ASCII file format. All comments in electronic form must be identified
by the document control number OPPTS-41048. No TSCA ``Confidential
Business Information'' (CBI) should be submitted through e-mail.
Electronic comments on the Fortieth Report may be filed online at many
Federal Depository Libraries. Additional information on electronic
submissions can be found in Unit IV of this document.
The public record supporting this action, including comments, is
available for public inspection in the TSCA Non-Confidential
Information Center (NCIC), Rm. NE B-607 at the address noted above from
12 noon to 4 p.m., Monday through Friday, except legal holidays.
FOR FURTHER INFORMATION CONTACT: Susan B. Hazen, Director,
[[Page 30581]]
Environmental Assistance Division (7408), Office of Pollution
Prevention and Toxics, Environmental Protection Agency, 401 M St., SW.,
Washington, DC 20460, 202-554-1404, TDD 202-554-0551.
SUPPLEMENTARY INFORMATION: EPA has received the TSCA Interagency
Testing Committee's Fortieth Report to the Administrator.
I. Background
TSCA (Pub. L. 94-469, 90 Stat. 2003 et seq.; 15 U.S.C. 260l et
seq.) authorizes the Administrator of the EPA to promulgate regulations
under section 4(a) requiring testing of chemicals and chemical groups
in order to develop data relevant to determining the risks that such
chemicals and chemical groups may present to health or the environment.
Section 4(e) of TSCA established the Interagency Testing Committee
(ITC) to recommend chemicals and chemical groups to the Administrator
of the EPA for priority testing consideration. Section 4(e) directs the
ITC to revise the TSCA section 4(e) Priority Testing List at least
every 6 months.
II. The ITC Fortieth Report
The most recent revisions to the Priority Testing List are included
in the ITC's Fortieth Report. The Report was received by the EPA
Administrator on April 28, 1997, and is included in this notice. The
Report removes two isocyanates that were recommended in the 26th Report
(55 FR 23050, June 5, 1990), one high production volume chemical,
trichloromethane sulfenyl chloride, that was recommended in the 36th
Report (60 FR 42982, August 17, 1995)(FRL-4965-6), and 2,4,6-
tribromophenol that was recommended in the 39th Report (62 FR 8578,
February 25, 1997)(FRL-5580-9).
Trichloromethane sulfenyl chloride is being removed from the
Priority Testing List because adequate subchronic toxicity data have
been submitted to the ITC, monitoring data indicate that
trichloromethane sulfenyl chloride is not likely to result in
significant exposures to workers, and no additional U.S. Government
data needs have been identified at this time.
The ITC is removing 2,4,6-tribromophenol from the Priority Testing
List after reviewing data obtained from the Chemical Manufacturers
Association's Brominated Flame Retardants Industry Panel Manager and
representatives from a 2,4,6-tribromophenol manufacturer. These data
demonstrated that:
1. 2,4,6-tribromophenol is used as a chemical intermediate to
produce bis(tribomophenoxy)ethane, tetrabromobisphenol (a carbonate and
epoxy oligomers), brominated epoxy resins and other flame retardants.
2. Greater than 99% of 2,4,6-tribromophenol produced as an end-
product is shipped overseas to be used as an intermediate in the
production of flame retardants.
3. Environmental and workplace monitoring indicate that 2,4,6-
tribromophenol is not likely to result in substantial environmental
releases or significant exposures to workers, consumers, or the general
population.
Finally, the two isocyanates are being removed from the Priority
Testing List because these chemicals are used as non-isolated
intermediates and this use, combined with a low estimated vapor
pressure (< 10-5 millimeter(mm) Mercury(Hg)@25 deg. C) for both
chemicals, is not likely to result in environmental releases or
exposures to workers, consumers, or the general population.
The ITC is also proposing procedures for chemical trade
associations and producers, importers, processors, and users of future
ITC-recommended chemicals to voluntarily provide data needed by U.S.
Government organizations represented on the ITC and thereby reduce the
need for the EPA to promulgate TSCA section 8 reporting rules for these
chemicals. The proposed procedures consist of:
1. Refining section 8 data needs.
2. Encouraging electronic data submissions.
3. Providing incentives for producers, importers, processors, and
users of chemicals recommended by the ITC to voluntarily submit section
8 information in a form that is rapidly reviewed by the ITC and to
establish partnerships with the ITC.
The ITC offers chemical trade associations, producers, importers,
processors, and users that provide the ITC with easy-to-review
(electronic) submissions and establish partnerships with the ITC the
opportunity to potentially eliminate promulgation of TSCA section 8(a)
preliminary assessment information reporting and section 8(d) health
and safety data reporting rules.
III. Status of the Priority Testing List
The current TSCA section 4(e) Priority Testing List contains 11
chemical groups, four of which were designated by the ITC for testing.
IV. Public Record
EPA invites interested persons to submit detailed comments on the
ITC's Fortieth Report.
A record has been established for this notice under document
control number OPPTS-41048 including comments submitted electronically
as described below. A public version of this record, including printed
paper versions of electronic comments, which does not contain any
information claimed as CBI, is available for inspection from 12 noon to
4 p.m., Monday through Friday, except legal holidays. The public record
is located in the TSCA Non-Confidential Information Center (NCIC), Rm.
NE B-607, Environmental Protection Agency, 401 M St., SW., Washington,
DC 20460.
Electronic comments can be sent directly to the ITC at:
[email protected] and to the EPA at
[email protected].
Electronic comments must be submitted as an ASCII file avoiding the
use of special characters and any form of security encryption. Comments
will also be accepted on disks in WordPerfect 5.1/6.1 file format or
ASCII file format.
The official record for the ITC's Fortieth Report, as well as the
public version as described above, will be kept in paper form.
Accordingly, EPA will transfer all comments received electronically
into printed, paper form as they are received and will place the paper
copies in the official record which will also include all comments
submitted directly in writing. The official record is the paper record
maintained at the EPA address in ``ADDRESSES'' at the beginning of this
document.
List of Subjects
Environmental protection, Chemicals, Hazardous substances.
Authority: 15 U.S.C. 2603.
Dated: May 28, 1997.
Charles M. Auer,
Director, Chemical Control Division, Office of Pollution Prevention and
Toxics.
Administrator, U.S. Environmental Protection Agency
Summary
This is the 40th Report of the TSCA Interagency Testing Committee
(ITC) to the Administrator of the U.S. Environmental Protection Agency
(EPA). In this Report, the ITC is revising its TSCA section 4(e)
Priority Testing List by removing two isocyanates that were recommended
in the 26th Report (55 FR 23050, June 5, 1990), one High Production
Volume Chemical, trichloromethane sulfenyl chloride that was
recommended in the 36th Report (60 FR 42982, August 17, 1995)(FRL-
[[Page 30582]]
4965-6), and 2,4,6-tribromophenol that was recommended in the 39th
Report (62 FR 8578, February 25, 1997)(FRL-5580-9). The ITC is also
proposing procedures for chemical trade associations and manufacturers,
importers, processors, and users of ITC-recommended chemicals to
voluntarily provide data needed by the U.S. Government organizations
represented on the ITC and thereby reduce the need for the EPA to
promulgate TSCA section 8 rules for these chemicals. Comments on this
Report should be submitted both to the ITC and the TSCA Public Docket.
The revised TSCA section 4(e) Priority Testing List follows as Table 1.
Table 1.--The TSCA Section 4(e) Priority Testing List (April 1997)\1\
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Report Date Chemical/Group Action
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26................................. May 1990.............. 8 Isocyanates............ Recommended with intent-
to-designate
27................................. November 1990......... 62 Aldehydes............. Recommended with intent-
to-designate
28................................. May 1991.............. Chemicals with Low Designated
Confidence RfD.
Acetone................
Thiophenol.............
29................................. November 1991......... 10 Alkyl-, bromo-, chloro- Recommended
, hydroxymethyl diaryl
ethers.
30................................. May 1992.............. 8 Siloxanes.............. Recommended
31................................. January 1993.......... 24 Chemicals with Designated
insufficient dermal
absorption rate data.
32................................. May 1993.............. 32 Chemicals with Designated
insufficient dermal
absorption rate data.
35................................. November 1994......... 24 Chemicals with Designated
insufficient dermal
absorption rate data.
36................................. May 1995.............. 9 High Production Volume Recommended
Chemicals (HPVCs).
37................................. November 1995......... 28 Alkylphenols and Recommended
Ethoxylates.
39................................. November 1996......... 23 Nonylphenol Recommended
Ethoxylates.
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\1\The list of discrete chemicals currently on the Priority Testing List is available from the ITC.
I. Background
The TSCA Interagency Testing Committee (ITC) was established by
section 4(e) of the Toxic Substances Control Act (TSCA) ``to make
recommendations to the Administrator respecting the chemical substances
and mixtures to which the Administrator should give priority
consideration for the promulgation of a rule for testing under section
4(a).... At least every six months..., the Committee shall make such
revisions in the Priority Testing List as it determines to be necessary
and to transmit them to the Administrator together with the Committee's
reasons for the revisions'' (Pub. L. 94-469, 90 Stat. 2003 et seq., 15
U.S.C. 2601 et seq.). Since its creation in 1976, the ITC has submitted
39 semi-annual (May and November) Reports to the EPA Administrator
transmitting the Priority Testing List and its revisions. These Reports
have been published in the Federal Register and are also available from
the ITC. The ITC meets monthly and produces its revisions of the List
with the help of staff and technical contract support provided by EPA.
ITC members and support personnel are listed at the end of this Report.
II. TSCA Section 8 Reporting
TSCA section 8 rules. Following receipt of the ITC's Report and the
addition of chemicals to the Priority Testing List, the EPA's Office of
Pollution Prevention and Toxics adds new chemicals from the List to
TSCA section 8(a) and 8(d) rules that require manufacturers and
importers of these chemicals to submit TSCA section 8(a) production and
exposure data and manufacturers, importers and processors of the listed
chemicals to submit TSCA section 8(d) health and safety studies within
60 days of the rules' effective date.
ITC's use of TSCA section 8 data. TSCA section 8(a) and 8(d)
submissions are indexed in databases that are maintained by EPA. The
ITC reviews the TSCA section 8(a) and 8(d) information and other
available data on chemicals and chemical groups (e.g., TSCA section
4(a) and 4(d) studies, TSCA section 8(c) submissions, TSCA section 8(e)
``substantial risk'' notices, ``For Your Information'' (FYI)
submissions to EPA, unpublished data submitted to U.S. Government
organizations on the ITC and published papers) to determine if
revisions to the List are necessary. Revisions can include changing a
general recommendation to a specific designation for testing action by
the EPA Administrator within 12 months, modifying the recommendation,
or removing the recommended or designated chemical or chemical group
from the List.
III. Procedures Promoting More Efficient Use of TSCA Section 8
Resources
A. Introduction
The ITC recognizes that substantive industry and government
resources may be consumed to:
1. Promulgate TSCA section 8(a) and 8(d) rules.
2. Retrieve and submit data in response to these rules.
3. Index and review the submitted data.
The ITC is proposing procedures (described below) that promote more
efficient use of these resources and that, in some cases, could
eliminate the need to promulgate future TSCA section 8(a) Preliminary
Assessment Information Reporting (PAIR) and section 8(d) Health and
Safety Data rules.
B. Procedures
In future Reports to the EPA Administrator, the ITC will implement
the following procedures to promote more efficient use of TSCA section
8(a) and 8(d) resources:
1. The ITC will recommend additional chemicals, add these chemicals
to the TSCA section 4(e) Priority Testing List, and describe specific
data necessary to meet the needs of U.S. Government organizations
represented on the ITC. Studies for which data are not required under
TSCA section 8(a) and 8(d) will be listed, if appropriate; e.g.,
studies on
[[Page 30583]]
mixtures and waste streams of certain chemicals.
2. In the Report describing additional chemical(s) added to the
Priority Testing List, the ITC will:
a. Ask the EPA not to promulgate TSCA section 8(a) PAIR and TSCA
section 8(d) Health and Safety Data rules.
b. Provide an opportunity for manufacturers, importers, processors,
and users of chemicals recommended by the ITC to voluntarily provide
FYI submissions. Two copies of FYI submissions should be mailed to the
Document Processing Center (7407), Attn: FYI Coordinator, Information
Management Division, Office of Pollution Prevention and Toxics, U.S.
Environmental Protection Agency, 401 M St., SW., Washington, DC 20460.
The cover letter should clearly identify the ITC as the recipient of
the submission.
Specific requested information should be submitted (e.g., exposure
and use information or toxicity studies) either by individual companies
and/or by a consortium as follows:
i. Manufacuturers, importers, processors, or users of chemicals
recommended by the ITC or a consortium representing all those
manufacturers, importers, processors or users must submit an e-mail or
letter of intent to the ITC Executive Director within 30 days of the
date the ITC Report is published in the Federal Register.
ii. The e-mail or letter of intent must include a list of the types
of data that will be voluntarily submitted and a timetable for the
submission of the data.
iii. The timetable should reflect the time needed by the ITC to
review the data before the next ITC Report is submitted to the EPA
Administrator. The e-mail and mailing addresses of the ITC Executive
Director are given at the end of this Report.
3. In a subsequent Report to the EPA Administrator, the ITC can ask
the EPA to promulgate TSCA section 8(a) PAIR and TSCA section 8(d)
Health and Safety Data rules for recommended chemical(s) if
insufficient voluntary information is submitted to evaluate the
recommended chemical(s). FYI studies should not be re-submitted as TSCA
section 8 studies.
C. Supplemental Information
The ITC has had some success in obtaining voluntary exposure, use,
and toxicity data from manufacturers, importers, processors, and users
of chemicals that have been recommended and added to the Priority
Testing List and establishing partnerships with chemical trade
associations representing those manufacturers, importers, processors,
and users. The ITC wants to pursue these voluntary approaches to data
sharing and offers a few examples that have been successful in the
past. In addition the ITC offers data to support its 30-day information
request.
1. Brominated flame retardants. The voluntary submission from the
Chemical Manufacturers Association's (CMA) Brominated Flame Retardants
Industry Panel (BFRIP) Manager and a manufacturer of 2,4,6-
tribromophenol provided production, importation, use, and exposure data
in a form that was rapidly and easily reviewed by the ITC. In response
to voluntarily providing these data in an easily-reviewed form, the ITC
requested that the EPA not promulgate a PAIR for 2,4,6-tribromophenol
and rapidly removed 2,4,6-tribromophenol from the List (see Unit V.A.1
of this ITC Report).
2. Propylene glycol ethers. The partnership with the CMA's
Propylene Glycol Ethers Panel provided data needed by the Consumer
Product Safety Commission (CPSC) that resulted in removal of all
propylene glycol ethers from the Priority Testing List (60 FR 42982,
August 17, 1995).
3. Silicones. The partnership with the Silicones Environmental
Health and Safety Council (SEHSC) provided data needed by the Food and
Drug Administration (FDA) and produced an electronic database of TSCA
section 8(d) studies in a format compatible with the TSCA Test
Submissions (TSCATS) database that resulted in removal of 43 of 56
siloxanes from the List (61 FR 4188, February 2, 1996).
Note: The ITC encourages manufacturers, importers, processors, or users
of chemicals recommended by the ITC to develop TSCATS-compatible
databases and to submit electronic information in a form that is
rapidly and easily reviewed by the ITC, e.g. the TSCA Electronic Cover
Sheet developed by the EPA and the CMA. TSCATS can be searched on the
Right-to-Know web site (http:www.rtk.net), where in the future it will
be possible to retrieve the TSCA Electronic Cover Sheet.
Thirty-day information requests. The ITC believes that 30 days from
the date the ITC Report is published in the Federal Register is
sufficient time for industry to submit an e-mail or letter of intent.
The ITC sends its Reports to hundreds of chemical trade associations,
chemical manufacturers, importers, processors, and users as well as
numerous public health and environmental groups and chemical industry
publications immediately after transmitting its Reports to the EPA
Administrator. With this advanced notice of recommended chemicals,
prior to Federal Register publication, the ITC recognizes that chemical
trade associations, and manufacturers, importers, processors, and users
of chemicals recommended by the ITC actually have 60- to 120-days
notice of the number and type of chemicals that are recommended.
IV. ITC's Partnership Activities During This Reporting Period
(November 1996 to April 1997)
Alkylphenols and ethoxylates. The ITC-CMA Alkylphenols and
Ethoxylates Dialogue Group was established in March 1996 to facilitate
the ITC's retrieval of information on uses, exposures, health effects,
and ecological effects of alkyphenols and ethoxylates, and the CMA's
understanding of data needed by the U.S. Department of the Interior
(DOI), the FDA, the EPA, the National Institute of Environmental Health
Sciences (NIEHS), and the U.S. Department of Agriculture (USDA). This
dialogue group met to discuss ongoing mammalian toxicology studies.
Isocyanates. The ITC-CMA Diisocyanates Dialogue Group was
established in November 1996 to facilitate the ITC's retrieval of
information on uses, exposures, and health effects of diisocyanates and
the CMA's understanding of data needed by the CPSC, the Department of
Defense (DOD), the EPA, the National Institute for Occupational Safety
and Health (NIOSH), and the Occupational Safety and Health
Administration (OSHA). This dialogue group met to discuss production
and commercial uses of diisocyanates.
Siloxanes. The ITC-SEHSC Dialogue Group was established in March
1993 to facilitate the ITC's retrieval of information on uses,
exposures, and health effects of siloxanes, and the SEHSC's
understanding of data needed by the FDA. This dialogue group met to
discuss ongoing health effects and exposure studies.
V. Revisions to the TSCA Section 4(e) Priority Testing List
Revisions to the TSCA section 4(e) Priority Testing List are
summarized in Table 2.
[[Page 30584]]
Table 2.-- Revisions to the TSCA Section 4(e) Priority Testing List
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CAS No. Chemical name Action Date
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118-79-6............................ 2,4,6-Tribromophenol...... Removed............... 4/97
High Production Volume
Chemicals.
594-42-3............................ Trichloromethane Removed............... 4/97
sulfenyl chloride.
Isocyanates...............
4035-89-6........................... Tris(isocyanatohexyl)biu Removed............... 4/97
ret.
5873-54-1........................... 1-Isocyanato-2-((4- Removed............... 4/97
isocyanatophenyl)methyl)b
enzene.
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A. Chemicals Removed From the Priority Testing List
1. 2,4,6-Tribromophenol--a. Rationale for removal. The ITC is
removing 2,4,6-tribromophenol from the Priority Testing List after
reviewing data obtained from the CMA's BFRIP Manager and
representatives from a 2,4,6-tribromophenol manufacturer. These data
demonstrated that:
i. 2,4,6-tribromophenol is used as a chemical intermediate to
produce bis(tribomophenoxy)ethane, tetrabromobisphenol A carbonate and
epoxy oligomers, brominated epoxy resins, and other flame retardants.
ii. Greater than 99% of 2,4,6-tribromophenol produced as an end-
product is shipped overseas to be used as an intermediate in the
production of flame retardants.
iii. Environmental and workplace monitoring indicate that 2,4,6-
tribromophenol is not likely to result in substantial environmental
releases or significant exposures to workers, consumers, or the general
population.
b. Supporting information. 2,4,6-Tribromophenol was recommended in
the ITC's 39th Report because the NIEHS needed chronic toxicology and
2-year carcinogenesis study data (62 FR 8578, February 25, 1997).
2,4,6-Tribromophenol was recommended and not designated because the ITC
wanted to promote a dialogue between 2,4,6-tribromophenol manufacturers
and the NIEHS to explain the need for chronic toxicity and 2-year
carcinogenesis study data.
Representatives of the ITC and NIEHS met with the CMA's BFRIP
Manager and representatives from a 2,4,6-tribromophenol manufacturer to
discuss data needs. The ITC and NIEHS representatives provided the CMA
with a copy of the 39th Report that summarized existing health and
safety data for 2,4,6-tribromophenol. The manufacturer's
representatives provided the ITC with a list of studies that were
previously submitted under TSCA section 8(d) and a list of producers,
applications, commercial activities, and sales statistics.
2. High Production Volume Chemicals (HPVCs)/trichloromethane
sulfenyl chloride--a. Rationale for removal. Trichloromethane sulfenyl
chloride (CAS No. 594-42-3) is being removed from the Priority Testing
List because adequate subchronic toxicity data have been submitted to
the ITC, monitoring data indicate that trichloromethane sulfenyl
chloride is not likely to result in significant exposures to workers,
and no additional U.S. Government data needs have been identified at
this time.
b. Supporting information. Trichloromethane sulfenyl chloride was a
member of a group of 35 HPVCs that were recommended for 90-day
subchronic toxicity testing in the ITC's 27th Report (56 FR 99534,
March 6, 1991). The Substructure-based Computerized Chemical Selection
Expert System (SuCCSES) was used to select these HPVCs during the ITC's
sixth scoring exercise. SuCCSES is used to identify chemicals with
shared substructures and associated health or ecological effects and
similar TSCA production or importation volumes (Ref. 3, Walker, 1995).
These HPVCs had annual production volumes exceeding one million pounds,
but no 90-day subchronic toxicity data to identify potential health
effects concerns. In its 36th Report (60 FR 42982, August 17, 1995),
the ITC solicited specific use and exposure information on 12 HPVCs to
facilitate its ability to decide whether these chemicals should be
removed from the Priority Testing List or designated for testing.
As noted in the 37th Report (61 FR 4188, February 2, 1996)(FRL-
4991-6), Zeneca, Inc. offered on September 19, 1995, to submit use and
exposure information. Zeneca, Inc. provided use and exposure
information to the ITC on August 14, 1996 (Ref. 4, Zeneca, 1996).
Zeneca reported that of the 7.5 million pounds trichloromethane
sulfenyl chloride produced per year, about 7 million pounds are
completely consumed in an on-site enclosed process to produce a
fungicide. Zeneca also reported that about 0.4 million pounds are
shipped to a customer and completely consumed in an on-site enclosed
process to produce a fungicide and that about 0.1 million pounds are
shipped to a customer and completely consumed in the production of
other substances. During manufacturing and use, about 5 workers per
site handle trichloromethane sulfenyl chloride. Exposures to workers
were less than 25% of the 1971 OSHA Permissable Exposure Level (PEL) of
0.1 parts per million (ppm) (0.8 milligram (mg)/meter (m)3).
The OSHA PEL was promulgated to protect workers against significant
risks of eye and respiratory tract irritation, nausea, and pulmonary
edema.
ICI Americas (now Zeneca) submitted a 1952 study; 2 dogs, 7 guinea
pigs, and 7 rats were exposed to a nominal concentration of 1 ppm
trichloromethane sulfenyl chloride for 3 months, 8 hours a day, 5 days
a week (Ref. 1, ICI Americas, 1952). Exposures to dogs caused
lacrimation, rhinorrhea, nausea, retching, coughing, and sneezing. At
the termination of exposure, one dog was sacrificed (the other was held
for observations, but no reports were provided) and the gross and
microscopic pathology were indicative of bronchopneumonia. Exposures to
guinea pigs caused lacrimation, rhinorrhea, and increased respiration;
6 guinea pigs died of pneumonia after 3 weeks. The rats survived, but
microscopic examinations of lung tissue revealed thin ruptured alveolar
walls, indicative of highly-irritating chemicals that can penetrate the
lung.
ICI Americas (now Zeneca) submitted a 1987 study; groups of 18 male
and 18 female Sprague-Dawley CD rats were exposed to trichloromethane
sulfenyl chloride vapor for 6 hours per day, 5 days per week for
between 70 and 72 exposure days (Ref. 2, ICI Americas, 1987).
Cumulative concentrations were within 90% of the target concentrations
of 0 (control), 0.1, 0.6, and 4 mg/m3. Treatment-related
decreases, relative to control values, were noted in body weights in
females at the 4 mg/m3 exposure level. Increased incidences
of salivation (4 mg/m3 exposure level for males) and
sneezing (0.6 and 4 mg/m3 exposure level for females; 4 mg/
m3 exposure level for males) were noted during the study. At
the time of necropsy, mucus was found in the
[[Page 30585]]
tracheas of 2 of 18 female and 4 of 18 male rats at the 4 mg/
m3 exposure level. Microscopic observations of acute
inflammation and hypertrophy and/or hyperplasia of the respiratory
nasal epithelium were noted in both sexes at the 4 mg/m3
exposure level. These microscopic alterations were apparently caused by
the toxic and irritating properties of trichloromethane sulfenyl
chloride. In conclusion, subchronic trichloromethane sulfenyl chloride
exposures in Sprague-Dawley rats produced treatment-related nasal
passage and lung alterations in the 0.6 and 4 mg/m3 exposure
levels. The no-observable-effect level (NOEL) in Sprague-Dawley rats
was 0.1 mg/m3.
3. Isocyanates--a. Rationale for removal. Two isocyanates are being
removed from the Priority Testing List because these chemicals are used
as non-isolated intermediates and this use, combined with a low
estimated vapor pressure (< 105 millimeter (mm) mercury (Hg)
@25 deg. C) for both chemicals, is not likely to result in
environmental releases or exposures to workers, consumers, or the
general population.
b. Supporting information. In its 26th Report, the ITC recommended
a group of 43 isocyanates for physical and chemical property testing in
response to a nomination from the EPA to support its TSCA New Chemicals
Program (55 FR 23050, June 5, 1990). The ITC removed 28 of these
isocyanates from the Priority Testing List in its 35th Report (59 FR
67596, December 29, 1994) and 5 more isocyanates in its 37th Report (61
FR 4188, February 2, 1996)(FRL-4923-2).
In its 37th Report, the ITC also solicited consumer use and
exposure data, information on the presence of diisocyanates in
commercially available products and information on exposures that
result from their use. In response to this solicitation, the ITC
established a dialogue with the CMA's Diisocyanates Panel and obtained
information on commercial uses. As a result, the ITC is removing 2
isocyanates from the Priority Testing List: tris(isocyanatohexyl)biuret
(CAS No. 4035-89-6) and isocyanato-2-((4-
isocyanatophenyl)methyl)benzene (CAS No. 5873-54-1). There are 8
isocyanates remaining on the List (Table 3).
Table 3.--Isocyanates remaining on the Priority Testing List
------------------------------------------------------------------------
CAS No. Chemical name
------------------------------------------------------------------------
91-08-7................................. 2,6-Toluene diisocyanate (2,6-
TDI)
101-68-8................................ 4,4'-Diphenylmethane
diisocyanate (MDI)
329-01-1................................ (,,-
Trifluoro-m-tolyl)isocyanate
584-84-9................................ 2,4-Toluene diisocyanate (2,4-
TDI)
4098-71-9............................... Isophorone diisocyanate
5124-30-1............................... 1,1'-Methylenebis(4-
isocyanatocyclohexane)
26447-40-5.............................. 1,1'-
Methylenebis(isocyanatobenzen
e)
26471-62-5.............................. Toluene diisocyanate (80% 2,4-
TDI; 20% 2,6-TDI)
------------------------------------------------------------------------
VI. References
(1) ICI Americas. Subchronic inhalation study with dogs, guinea
pigs and rats (1952). DCN 88-920007341 and Fiche No.
OTS0538474.1
---------------------------------------------------------------------------
1Studies are available at the EPA's TSCA Non-Confidential
Information Center from noon until 4 p.m., Monday through Friday.
The center is located in Rm. B-607 of EPA's NE Mall, 401 M St., SW.,
Washington, DC. Studies on microfiche are also available from the
National Technical Information Service, 5285 Port Royal Road,
Springfield, VA 22161, and the Chemical Information Systems, Inc.,
7215 York Road, Baltimore, MD 21212. Studies can be retrieved by
using either the document control number (DCN) or fiche number
(Fiche No.).
---------------------------------------------------------------------------
(2) ICI Americas. Subchronic inhalation study with rats (1987). DCN
88-920007422 and Fiche No. OTS054675.2
---------------------------------------------------------------------------
2Ibid.
---------------------------------------------------------------------------
(3) Walker, J.D. Estimation Methods Used by the TSCA Interagency
Testing Committee to Prioritize Chemicals for Testing: Exposure and
Biological Effects Scoring and Structure Activity Relationships.
Toxicology Modeling 1:123-141 (1995).
(4) Zeneca. August 14, 1996 letter from Ms. Terry L. Wells, Product
Regulatory Specialist, Zeneca Specialities, Wilmington, Delaware to Dr.
John D. Walker, Executive Director, ITC, OPPT/EPA, Washington, DC
(1996).
VII. TSCA Interagency Testing Committee
Statutory Organizations and Their Representatives
Council on Environmental Quality
Brad Campbell, Member
Douglas Sanders, Alternate
Department of Commerce
Edward White, Member
Environmental Protection Agency
David R. Williams, Member
Lois Dicker, Alternate
National Cancer Institute
Victor Fung, Member, Chair
Harry Seifried, Alternate
National Institute of Environmental Health Sciences
William Eastin, Member, Vice Chair
H.B. Matthews, Alternate
National Institute for Occupational Safety and Health
Henryka Nagy, Member
David A. Dankovic, Alternate
National Science Foundation
Linda Duguay, Member
Occupational Safety and Health Administration
Lyn Penniman, Member
Christine Whittaker, Alternate
Liaison Organizations and Their Representatives
Agency for Toxic Substances and Disease Registry
William Cibulas, Member
Consumer Product Safety Commission
Val Schaeffer, Member
Lakshmi C. Mishra, Alternate
Department of Agriculture
Clifford P. Rice, Alternate
Department of Defense
David A. Macys, Member
Department of the Interior
Barnett A. Rattner, Member
Food and Drug Administration
Edwin J. Matthews, Member
Raju Kammula, Alternate
National Library of Medicine
Vera Hudson, Member
National Toxicology Program
NIEHS, FDA, and NIOSH Members
Counsel
Mary Ellen Levine, Office of General Counsel, EPA
Technical Support Contractor
Syracuse Research Corporation
ITC Staff
John D. Walker, Executive Director
Norma S.L. Williams, Executive Assistant
TSCA Interagency Testing Committee, U.S. EPA/OPPT (MC/7401) 401 M St.,
SW., Washington, DC 20460, Phone: 202-260-1825, Fax: 202-260-7895, E-
mail: [email protected].
[FR Doc. 97-14578 Filed 6-3-97; 8:45 am]
BILLING CODE 6560-50-F