[Federal Register Volume 62, Number 37 (Tuesday, February 25, 1997)]
[Notices]
[Pages 8578-8583]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-4620]
[[Page 8577]]
_______________________________________________________________________
Part III
Environmental Protection Agency
_______________________________________________________________________
Thirty-Ninth Report of the Interagency Testing Committee to the
Administrator; Receipt of Report, Request for Comments; Notice
Federal Register / Vol. 62, No. 37 / Tuesday, February 25, 1997 /
Notices
[[Page 8578]]
ENVIRONMENTAL PROTECTION AGENCY
[OPPTS-41046; FRL-5580-9]
Thirty-Ninth Report of the TSCA Interagency Testing Committee
(ITC) to the Administrator; Receipt of Report, Request for Comments
AGENCY: Environmental Protection Agency (EPA).
ACTION: Notice.
-----------------------------------------------------------------------
SUMMARY: The TSCA Interagency Testing Committee (ITC), established
under section 4(e) of the Toxic Substances Control Act (TSCA),
transmitted its Thirty-Ninth Report to the Administrator of the EPA on
November 27, 1996. In the Thirty-Ninth Report, which is included with
this Notice, the ITC revised the TSCA section 4(e) Priority Testing
List by recommending 2,4,6-tribromophenol, re-recommending 23
nonylphenol ethoxylates and removing 5 siloxanes. Moreover, the ITC
requested that EPA stay certain provisions in the Agency's October 29,
1996, TSCA section 8(a) and 8(d) information reporting rules for the
nonylphenol ethoxylates recommended in the ITC's Thirty-Eighth Report
There are no designated or recommended with intent-to-designate
chemicals or chemical groups in the Thirty-Ninth Report. EPA invites
interested persons to submit written comments on the Report.
DATES: Written comments on the Thirty-Ninth ITC Report should be
received by March 27, 1997.
ADDRESSES: Comments on the Thirty-Ninth 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 docket number OPPTS-41046.
Comments may also be submitted electronically by sending electronic
mail (e-mail) to: [email protected] or to the EPA at:
[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 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
docket number OPPTS-41046. No TSCA ``Confidential Business
Information'' (CBI) should be submitted through e-mail. Electronic
comments on the Thirty-Ninth 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,
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 Thirty-Ninth 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 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 Thirty-Ninth Report
The most recent revisions to the Priority Testing List are included
in the ITC's Thirty-Ninth Report. The Report was received by the EPA
Administrator on November 27, 1996, and is included in this Notice. The
Report recommends 2,4,6-tribromophenol, re-recommends 23 nonylphenol
ethoxylates and removes 5 siloxanes from the Priority Testing List.
2,4,6-Tribromophenol is being recommended to meet the data needs of the
National Institute of Environmental Health Sciences (NIEHS). The
nonylphenol ethoxylates are being re-recommended to meet the data needs
of the Department of the Interior (DOI), the EPA, the Food and Drug
Administration (FDA) and the NIEHS and to eliminate any ambiguities in
TSCA section 8(a) and 8(d) reporting resulting from the previous use of
alternate Chemical Abstracts Service (CAS) registry numbers in the
ITC's Thirty-Eighth Report (61 FR 39832; July 30, 1996; FRL-5379-2).
The ITC re-examined these alternate CAS registry numbers and determined
that five were not associated with any of the listed nonylphenol
ethoxylate chemical names. In the Thirty-Ninth Report, the ITC revised
the list of nonylphenol ethoxylates by providing Ninth Collective Index
names for all CAS-numbered nonylphenol ethoxylates, including the five
not previously associated with a unique chemical name. This process
eliminated the need for alternate CAS registry numbers. The ITC
requested that the EPA stay certain provisions in the October 29, 1996,
TSCA section 8(a) and 8(d) rules (61 FR 55871; FRL-5397-9) promulgated
for the nonylphenol ethoxylates originally recommended in the ITC's
Thirty-Eighth Report (61 FR 39832; July 30, 1996; FRL-5379-2). The EPA
issued the stay which was published on December 11, 1996 (61 FR 65186;
FRL-5577-5). Nothing in this Notice changes the status of the stayed
rules affecting the nonylphenol ethoxylates. These rules remain stayed,
and the EPA will address their future status in a subsequent Federal
Register Notice.
III. Status of the Priority Testing List
The current TSCA section 4(e) Priority Testing List contains 1
individual chemical and 11 chemical groups; of these, 4 chemical groups
were designated for testing.
IV. Electronic Comments
The EPA invites interested persons to submit detailed comments on
the ITC's Thirty-Ninth Report.
A record has been established for this Notice under docket number
OPPTS-41046 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 TSCA ``Confidential Business Information'' (CBI), is
available for inspection from 12 noon to 4 p.m., Monday through Friday,
excluding legal holidays. The public record is located in the TSCA Non-
Confidential Information Center, 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].
[[Page 8579]]
Electronic comments must be submitted as an ASCII file avoiding the
use of special characters and any form of security encryption. Comments
will be accepted on disks in WordPerfect 5.1/6.1 file format or ASCII
file format.
The official record for the ITC's Thirty-Ninth 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.
Authority: 15 U.S.C. 2603.
Dated: February 13, 1997.
Charles M. Auer,
Director, Chemical Control Division, Office of Pollution Prevention and
Toxics.
Administrator, U.S. Environmental Protection Agency
Summary
This is the 39th 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 recommending 2,4,6-tribromophenol, re-
recommending 23 nonylphenol ethoxylates and removing 5 siloxanes.
2,4,6-Tribromophenol is being recommended to meet the data needs of the
National Institute of Environmental Health Sciences (NIEHS). The
nonylphenol ethoxylates are being re-recommended to meet the data needs
of the Department of the Interior (DOI), the EPA, the Food and Drug
Administration (FDA) and the NIEHS and to eliminate any ambiguities in
TSCA section 8(a) and 8(d) reporting resulting from the previous use of
alternate CAS numbers in the ITC's 38th Report (61 FR 39832, July 30,
1996). 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 (November 1996)
----------------------------------------------------------------------------------------------------------------
Report Date Chemical/Group Action
----------------------------------------------------------------------------------------------------------------
26................................... May 1990 10 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-, Recommended
chloro-, 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 10 High Production Recommended
Volume Chemicals
(HPVCs)
37................................... November 1995 28 Alkylphenols and Recommended
Ethoxylates
39................................... November 1996 23 Nonylphenol Recommended
Ethoxylates
39................................... November 1996 2,4,6-Tribromophenol Recommended
----------------------------------------------------------------------------------------------------------------
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 6 months..., the Committee shall make such
revisions in the 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 38 semi-annual
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. ITC's Activities During this Reporting Period (May to October,
1996)
Alkylphenols and ethoxylates. The ITC-Chemical Manufacturers
Association (CMA) Alkylphenols and Ethoxylates Dialog Group met to
discuss environmental monitoring, ecological effects, biodegradation
and mammalian toxicology studies. This Dialog Group was established to
facilitate the ITC's retrieval of information on uses, exposures and
effects of alkyphenols and ethoxylates, and the CMA's understanding of
data needed by the DOI, the FDA, the EPA and the NIEHS.
Siloxanes. The ITC-Silicones Environmental Health and Safety
Council (SEHSC) Dialog Group met to discuss ongoing health effects and
exposure studies. This Dialog Group was established to facilitate the
ITC's retrieval of information on uses, exposures and effects of
siloxanes, and the SEHSC's understanding of data needed by the FDA.
Isocyanates. During this reporting period, the ITC received
information from the CMA's Diisocyanates Panel. The ITC's Isocyanates
Subcommittee will review this information and discuss potential
consumer uses, occupational exposures and health effects of isocyanates
with the CMA Panel.
High Production Volume Chemicals (HPVCs). Through its 36th Report
and letters to manufacturers and importers of HPVCs, the ITC is
receiving use and exposure data for the 10 HPVCs remaining on the
Priority Testing List. The ITC is reviewing these data.
Diaryl ethers. The ITC has identified manufacturers and importers
of diaryl
[[Page 8580]]
ethers and is interested in working with them to obtain use and
exposure data. Diaryl ethers were recommended in the ITC's 29th Report
(56 FR 67424, December 30, 1991). An invitation to discuss use and
exposure data and to develop Structure Activity Relationships for
diaryl ethers was announced in the ITC's 38th Report (61 FR 39832, July
30, 1996)(FRL-5379-2).
2,4,6-Tribromophenol. Representatives of the ITC met with the CMA's
Brominated Flame Retardants Industry Panel (BFRIP) Manager and
representatives from a 2,4,6-tribromophenol manufacturer to discuss the
data needs of the NIEHS. The ITC representatives provided the CMA with
a copy of the National Toxicology Program (NTP) data summary for 2,4,6-
tribromophenol (Ref. 5, NTP, 1996). The 2,4,6-tribromophenol
manufacturer's representatives provided the ITC with a list of health
effects, chemical fate, and ecological effects studies that were
previously submitted under TSCA section 8(d) and reviewed by the ITC.
These representatives also provided the ITC with a list of 2,4,6-
tribromophenol producers, applications, commercial activities and sales
statistics. The ITC is interested in promoting a dialog that is
mutually beneficial to the NIEHS and the BFRIP.
III. TSCA Section 8 Reporting
Following receipt of the ITC's Report and the addition of chemicals
to the Priority Testing List, 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 rule's effective date. Unless otherwise noted in Unit IV A of this
ITC Report, the ITC is requesting that the EPA exempt manufacturers and
importers of chemicals added to the List from submitting studies
conducted on mixtures (e.g., formulated products) containing a subject
substance at a level below 1 percent of the mixture, unless a purpose
of the study includes the investigation of the effects of an 8(d) rule-
listed substance at levels below 1 percent (40 CFR 716.20(b)(4)).
TSCA section 8(a) and 8(d) submissions are indexed and 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 8(e) ``substantial risk'' notices, ``For Your Information''
(FYI) submissions to EPA, 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 recommended
testing, or removing the chemical or chemical group from the List.
IV. 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.
Table 2.--Revisions to the TSCA section 4(e) Priority Testing List
----------------------------------------------------------------------------------------------------------------
CAS No. Chemical Name Action Date
----------------------------------------------------------------------------------------------------------------
118-79-6............................ 2,4,6-Tribromophenol Recommended 11/96
Nonylphenol ethoxylates Recommended 11/96
7311-27-5........................... Ethanol, 2-[2-[2-[2-(4-
nonylphenoxy)
ethoxy]ethoxy]ethoxy]-
9016-45-9........................... Poly(oxy-1,2-
ethanediyl), .alpha.-
(nonylphenyl)-.omega.-
hydroxy-
20427-84-3.......................... Ethanol, 2-[2-(4-
nonylphenoxy)ethoxy]-
20636-48-0.......................... 3,6,9,12-
Tetraoxatetradecan-1-
ol, 14-(4-nonylphenoxy)-
26027-38-3.......................... Poly(oxy-1,2-
ethanediyl), .alpha.-(4-
nonylphenyl)-.omega.-
hydroxy-
26264-02-8.......................... 3,6,9,12-
Tetraoxatetradecan-1-
ol, 14-(nonylphenoxy)-
26571-11-9.......................... 3,6,9,12,15,18,21,24-
Octaoxahexacosan-1-ol,
26-(nonylphenoxy)-
27176-93-8.......................... Ethanol, 2-[2-
(nonylphenoxy)ethoxy]-
27177-01-1.......................... 3,6,9,12,15-
Pentaoxaheptadecan-1-
ol, 17-(nonylphenoxy)-
27177-05-5.......................... 3,6,9,12,15,18,21-
Heptaoxatricosan-1-ol,
23-(nonylphenoxy)-
27177-08-8.......................... 3,6,9,12,15,18,21,24,27-
Nonaoxanonacosan-1-ol,
29-(nonylphenoxy)-
27986-36-3.......................... Ethanol, 2-
(nonylphenoxy)-
37205-87-1.......................... Poly(oxy-1,2-
ethanediyl), .alpha.-
(isononylphenyl)-
.omega.-hydroxy-
51938-25-1.......................... Poly(oxy-1,2-
ethanediyl), .alpha.-(2-
nonylphenyl)-.omega.-
hydroxy-
65455-72-3.......................... 3,6,9,12,15,18,21,24,27-
Nonaoxanonacosan-1-ol,
29-(isononylphenoxy)-
68412-54-4.......................... Poly(oxy-1,2-
ethanediyl), .alpha.-
(nonylphenyl)-.omega.-
hydroxy-, branched
98113-10-1.......................... NP 9
127087-87-0......................... Poly(oxy-1,2-
ethanediyl), .alpha.-(4-
nonylphenyl)-.omega.-
hydroxy-, branched
152143-22-1......................... Poly(oxy-1,2-
ethanediyl), .alpha.-(4-
nonylphenyl)-.omega.-
hydroxy-, branched,
phosphates
NAa................................. Nonoxynol-2
NA.................................. Nonoxynol-3
NA.................................. Nonoxynol-7
NA.................................. .alpha.-(4-Nonylphenol)-
.omega.-hydroxypoly-
(oxyethylene)-
5 Siloxanes Remove previously 11/96
Recommended chemicals
69430-24-6.......................... Cyclopolydimethylsiloxan
e (Dx)
68083-14-7.......................... Dimethyl, diphenyl
siloxanes and silicones
67762-90-7.......................... Dimethyl silicones and
siloxanes, reaction
products with silica
68037-74-1.......................... Dimethylmonomethylpolysi
loxanes
70131-67-8.......................... Dimethyl silicones and
siloxanes hydroxy
terminated
----------------------------------------------------------------------------------------------------------------
aNot Assigned.
[[Page 8581]]
A. Chemicals Added to the Priority Testing List
Recommendations
a. 2,4,6-Tribromophenol-- rationale for recommendation. The ITC is
recommending 2,4,6-tribromophenol at this time because the NIEHS needs
chronic toxicology and 2-year carcinogenesis study data. As part of its
continuing efforts to coordinate testing activities, the ITC is
recommending and not designating 2,4,6-tribromophenol because it is
currently promoting a dialog between a 2,4,6-tribromophenol
manufacturer and the NIEHS to explain the need for chronic toxicity and
2-year carcinogenesis study data.
Background. Previous activities of the ITC, EPA and NTP for 2,4,6-
tribromophenol are summarized below.
ITC. In the ITC's 25th Report, 2,4,6-tribromophenol and six other
brominated flame retardants were recommended for chronic health effects
testing, chronic ecological effects testing, and physical/chemical
properties and persistence testing (54 FR 51114, December 12, 1989). In
response to the 25th Report, as noted below, the EPA required the
submission of TSCA section 8(a) and 8(d) data.
In the ITC's 33rd Report, 2,4,6-tribromophenol was removed from the
Priority Testing List to give adequate priority to testing needs for
other chemicals, e.g., those with U.S. Government data needs (59 FR
3764, January 26, 1994). At the time 2,4,6-tribromophenol was removed
from the List, the ITC acknowledged that there were no existing U.S.
Government data needs, but agreed to reconsider the chemical if data
were needed in the future.
At this time, the ITC is requesting that the EPA not promulgate
additional TSCA section 8 rules for 2,4,6-tribromophenol for the
following reasons. First, the ITC has reviewed the TSCA section 8(a)
and (d) data submitted under the previously-promulgated rules. Second,
under the previously-promulgated TSCA section 8(d) rule, the ITC will
learn of any new studies that are initiated. Third, the ITC believes
that a dialog with the U.S. producer is likely to provide use and other
relevant data that could not be obtained by re-promulgating these
rules.
EPA. 2,4,6-Tribromophenol was included in a 1987 EPA TSCA section 4
test rule requiring that manufacturers and importers of 12 chemicals
test for the presence of certain chlorinated and brominated dibenzo-p-
dioxins and dibenzofurans (52 FR 21412, June 5, 1987). None of the
seven 2,4,6-tribromophenol samples that were analyzed contained
concentrations of brominated dibenzo-p-dioxins and dibenzofurans that
were above the levels of quantitation (0.1 ppb for 2,3,7,8-
tetrabrominated dibenzo-p-dioxin and 1 ppb for 2,3,7,8-tetrabrominated
dibenzofuran).
2,4,6-Tribromophenol was also included in 1989 EPA TSCA section 8
rules promulgated for the ITC. These rules required the submission of
production and exposure data and unpublished health and safety data
under TSCA sections 8(a) and 8(d), respectively (54 FR 51131, December
12, 1989).
NTP. At the July 15, 1996 meeting of the NTP Interagency Committee
for Chemical Evaluation and Coordination, the NIEHS identified data
needs for 2,4,6-tribromophenol. The NIEHS needs chronic toxicology and
2-year carcinogenesis study data for 2,4,6-tribromophenol based on the
absence of toxicology and carcinogenicity data and carcinogenicity data
for 2,4,6-trichlorophenol, (Ref. 5, NTP, 1996).
Existing Data. 2,4,6-Tribromophenol is a chemical intermediate that
is produced in closed process equipment, kept within that equipment and
reacted to make flame retardants (Ref. 1, GLCC, 1996a). Recent
production volumes ranged from 1 to 15 million pounds (Ref. 6, Walker,
1994).
The number of employees involved in the production, packaging, or
handling of 2,4,6-tribromophenol is quite small. While the exact number
of operators is confidential information, less than 50 workers have the
potential for intermittent exposure to 2,4,6-tribromophenol during
their normal workday (Ref.1, GLCC, 1996a). The use of closed processes
limits potential exposure, but even this exposure is controlled through
the use of local exhaust ventilation, personal protective equipment and
other industrial hygiene practices where dust or vapor exposure might
occur (Ref. 1, GLCC, 1996a). Flaked 2,4,6-tribromophenol contains
particles (estimated to be 1 to 10 mm) which do not easily become
airborne.
During domestic production of 2,4,6-tribromophenol, air emissions
are regulated by State permits and releases to surface waters either do
not occur or occur after discharge to Publicly Owned Treatment Works
(Ref. 1, GLCC, 1996a). The only operation where 2,4,6-tribromophenol is
not in closed reactors or piping is the flaking and packaging
operation. Vapors and fine particulates from this process are
controlled by a local exhaust system. Using a ``worst case'' assumption
that the manufacturing facility operated 24 hour/day, 365 days per year
(8,760 hours), annual point source emissions would be less than 90
pounds per year (Ref. 2, GLCC, 1996b).
2,4,6-Tribromophenol was not found to be mutagenic in the Ames
assay (Ref. 8, Zeiger et al., 1987) or in the mouse lymphoma assay
(Ref. 4, NCI, 1996). Doses ranging from 2,000 to 8,000 mg/kg were
required to produce acute effects in laboratory animals by oral, dermal
or inhalation exposures (Ref. 5, NTP, 1996).
The TSCA section 8 data for 2,4,6-tribromophenol were recently
published in two reviews (Refs. 6 and 7, Walker, 1994; 1996). Data
cited in the 1996 review indicated that 2,4,6-tribromophenol can be
highly toxic to fish (LC50 values <1 mg/L) but less toxic to
daphnids, in acute toxicity tests. Health effects studies cited in the
1994 review are summarized below.
In a 28-day dermal toxicity study, groups of 4 rabbits/sex/dose
were used. Doses of 0, 100, 300 and 1,000 mg/kg were applied as skin
suspensions 5 days a week for 4 weeks. At the highest dose (1,000 mg/
kg) 1 male rabbit died. At doses of 100 and 300 mg/kg 2,4,6-
tribromophenol was slightly irritating, but there were no treatment-
related effects on body weight, clinical chemistry or organ weights
(Ref. 6, Walker, 1994).
In a developmental toxicity screening study, groups of 5 pregnant
rats were administered gavage doses of 2,4,6-tribromophenol in corn oil
from gestation day 6 to 15. Doses of 0, 10, 30, 100, 300, 1,000 and
3,000 mg/kg/day were administered. All rats receiving 3,000 mg/kg/day
died; animals receiving 1,000 mg/kg/day showed increased post
implantation losses and a slight decrease in number of viable fetuses.
Rats receiving 300 mg/kg/day or less showed no compound-related
differences in maternal body weight, number of viable fetuses,
resorptions, implantations or corpora lutea when compared with the
controls (Ref. 6, Walker, 1994).
In an inhalation study, groups of 5 male and 5 female rats were
exposed to 0, 0.1 and 0.9 mg/L 2,4,6-tribromophenol for 6 hours/day, 5
days/week for 3 weeks. Exposures to both doses of 2,4,6-tribromophenol
produced liver and kidney lesions. At necropsy, 4/5 male and 5/5 female
rats in the 0.1 mg/L dose group were emaciated (Ref. 6, Walker, 1994).
The NIEHS data needs are supported by carcinogenicity data for a
close structural analog, 2,4,6-trichlorophenol (CAS No. 88-06-2). In a
feeding study 2,4,6-trichlorophenol was a carcinogen in male rats and
male and female mice, inducing lymphomas or leukemias in
[[Page 8582]]
male F344 rats; and increasing the incidence of hepatocellular
carcinomas or adenomas in male and female B6C3F1 mice (Ref. 3, NCI,
1979).
b. Nonylphenol ethoxylates--rationale for recommendation. Twenty-
three (23) nonylphenol ethoxylates are being re-recommended to
eliminate any ambiguities in TSCA section 8(a) and 8(d) reporting
resulting from the previous use of alternate CAS numbers in the ITC's
38th Report (61 FR 39832, July 30, 1996).
Background. Eighteen (18) nonylphenol ethoxylates were recommended
in the ITC's 38th Report (61 FR 39832, July 30, 1996). Alternate CAS
registry numbers were listed for some of these nonylphenol ethoxylates.
The use of alternate CAS numbers produced some ambiguities in the TSCA
section 8(a) and 8(d) rules that were promulgated for the nonylphenol
ethoxylates (61 FR 55871, October 29, 1996). The ITC re-examined these
alternate CAS registry numbers and determined that five were not
associated with any of the listed nonylphenol ethoxylate chemical
names. The ITC revised the list of nonylphenol ethoxylates by providing
ninth collective index names for all CAS-numbered nonylphenol
ethoxylates, including the five not previously associated with a unique
chemical name. This process eliminated the need for alternate CAS
registry numbers. The ITC is requesting that the EPA stay certain
provisions in the October 29, 1996 TSCA section 8(a) and 8(d) rules
promulgated for nonylphenol ethoxylates (61 FR 55871) because of
ambiguities in reporting requirements associated with the use of
alternate CAS registry numbers in the ITC's 38th Report (61 FR 39832,
July 30, 1996). The ITC is requesting that the EPA promulgate the TSCA
section 8(a) and 8(d) rules using the 23 nonylphenol ethoxylates in
Table 2 of this ITC Report.
B. Chemicals Removed from the Priority Testing List
Silicone chemicals. Fifty-six (56) silicone chemicals were
recommended for health effects testing in the ITC's 30th Report to meet
the data needs of the Food and Drug Administration (FDA) (57 FR 30608,
July 9, 1992). After this recommendation, the ITC's Silicones
Subcommittee established a Dialog Group with the Silicones
Environmental Health and Safety Council (SEHSC). The ITC-SEHSC Dialog
Group has discussed unpublished toxicity data, current use and exposure
data, and developed a prototype computer file of physical and chemical
properties, health effects and use data that could be used by other
government and trade organizations. As a result of the Dialog Group's
discussions, the ITC removed 43 of the previously-recommended silicone
chemicals from the Priority Testing List in its 37th Report (61 FR
4188, February 2, 1996; FRL-4991-6). As a result of further Dialog
Group discussions, the ITC is removing five more siloxanes from the
List in this Report (Table 3). The eight siloxanes remaining on the
List are included in Table 4.
Table 3.--Previously-Recommended Silicone Chemicals Removed from the
Priority Testing List
------------------------------------------------------------------------
CAS No. Chemical Name Removal Rationale
------------------------------------------------------------------------
69430-24-6................... Cyclopolydimeth Toxicity of
ylsiloxane cyclopolydimethylsiloxa
(Dx) ne is likely to be
predicted from testing
octamethylcyclotetrasil
oxane (D4),
decamethylcyclopentasil
oxane (D5) and
dodecamethylcyclohexasi
loxane (D6) (see Table
4).
Cyclopolydimethylsiloxa
ne is used only as a
site-limited
intermediate to
manufacture D4, D5 and
D6.
68083-14-7................... Dimethyl, Low exposure potential
diphenyl based on annual
siloxanes and production volume and
silicones specialized uses.
67762-90-7................... Dimethyl Toxicity of siloxane
silicones and polymers bearing CAS
siloxanes, numbers 67762-90-7,
reaction 68037-74-1 and 70131-67-
products with 8 is likely to be
silica predicted from testing
dimethyl silicones and
siloxanes bearing CAS
number 63148-62-9 (see
Table 4). Dimethyl
silicones and siloxanes
is a siloxane polymer
of lower molecular
weight, lower cross-
linking ability and
greater bioavailability
potential than these 3
siloxane polymers.
68037-74-1................... Dimethylmonomet Toxicity of siloxane
hylpolysiloxan polymers bearing CAS
es numbers 67762-90-7,
68037-74-1 and 70131-67-
8 is likely to be
predicted from testing
dimethyl silicones and
siloxanes bearing CAS
number 63148-62-9 (see
Table 4). Dimethyl
silicones and siloxanes
is a siloxane polymer
of lower molecular
weight, lower cross-
linking ability and
greater bioavailability
potential than these 3
siloxane polymers.
70131-67-8................... Dimethyl Toxicity of siloxane
silicones and polymers bearing CAS
siloxanes numbers 67762-90-7,
hydroxy 68037-74-1 and 70131-67-
terminated 8 is likely to be
predicted from testing
dimethyl silicones and
siloxanes bearing CAS
number 63148-62-9 (see
Table 4). Dimethyl
silicones and siloxanes
is a siloxane polymer
of lower molecular
weight, lower cross-
linking ability and
greater bioavailability
potential than these 3
siloxane polymers.
------------------------------------------------------------------------
The eight siloxanes remaining on the Priority Testing List shown in
table 4.
Table 4.--Siloxanes Remaining On The Priority Testing List
------------------------------------------------------------------------
CAS No. Chemical Name
------------------------------------------------------------------------
Cyclic Siloxanes..........................
556-67-2................................ Octamethylcyclotetrasiloxane
(D4)
541-02-6................................ Decamethylcyclopentasiloxane
(D5)
540-97-6................................ Dodecamethylcyclohexasiloxan
e (D6)
Linear Siloxanes..........................
107-46-0................................ Hexamethyldisiloxane (L2)
107-51-7................................ Octamethyltrisiloxane (L3)
141-62-8................................ Decamethyltetrasiloxane (L4)
141-63-9................................ Dodecamethylpentasiloxane
(L5)
Polymers..................................
63148-62-9.............................. Dimethyl silicones and
siloxanes
9006-65-9a..............................
9016-00-6a .............................
------------------------------------------------------------------------
aAlternate CAS numbers are listed for this chemical.
[[Page 8583]]
References
(1) GLCC. November 13, 1996, Letter from Mr. Robert C. Campbell,
TSCA Compliance Manager, Great Lakes Chemical Corporation (GLCC), West
Lafayette, Indiana to Dr. John D. Walker, Executive Director, ITC, U.S.
EPA, Washington, DC (1996a).
(2) GLCC. November 15, 1996, Letter from Mr. Robert C. Campbell,
TSCA Compliance Manager, Great Lakes Chemical Corporation (GLCC), West
Lafayette, Indiana to Dr. John D. Walker, Executive Director, ITC, U.S.
EPA, Washington, DC (1996b).
(3) NCI. Bioassay of 2,4,6-trichlorophenol for possible
carcinogenicity (CAS No. 88-06-2) (Technical Report Series No. 155;
Department of Health Education and Welfare (DHEW) Publication No. (NIH)
79-1711). DHEW, Washington, DC. 115 pp. (1979).
(4) NCI. NCI/DCB Short-term test program. Ames Salmonella
typhimurium/mouse lymphoma L5178Y, H. Seifried, Ph.D., Project Officer
(1996).
(5) NTP. Draft NTP data summary for 2,4,6-tribromophenol (CAS No.
118-79-6). NTP, Research Triangle Park, NC. 19 pp. (1996).
(6) Walker, J.D. Testing decisions of the TSCA Interagency Testing
Committee for brominated flame retardants: A review of decisions and
health and safety data. pp. 185-220. In The Future of Fire Retarded
Materials: Applications and Regulation. Fire Retardant Chemicals
Association, Lancaster, PA. (1994).
(7) Walker, J.D. Testing decisions of the TSCA Interagency Testing
Committee for chemicals on Canada's Domestic Substances List and
Priority Substances List: Di-tert-butylphenol, ethyl benzene,
brominated flame retardants, phthalate esters, chloroparaffins,
chlorinated benzenes and anilines. pp. 18-54. In T.W. LaPoint, F.T.
Price, and E.E. Little (eds.), Environmental Toxicology and Risk
Assessment: Fourth Volume, ASTM STP 1241, ASTM, Philadelphia (1996).
(8) Zeiger, E., B. Anderson, S. Haworth, T. Lawlor, K. Mortelmans
and W. Speck. Salmonella mutagenicity tests: III. Results from testing
of 255 chemicals. Environmental Molecular Mutagenicity 9 (Suppl.9), 1-
110 (1987).
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
H.B. Matthews, Alternate
National Institute for Occupational Safety and Health
Henryka Nagy, Member, Vice Chair
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 Rice, Member
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.
Internet:[email protected]
[FR Doc. 97-4620 Filed 2-24-97; 8:45 am]
BILLING CODE 6560-50-F