4188 Federal Register / Vol. 61, No. 23 / Friday, February 2, 1996 / Notices

ENVIRONMENTAL PROTECTION

AGENCY

[OPPTS–41044; FRL–4991–6]

Thirty-Seventh Report of the TSCA

Interagency Testing Committee to the

Administrator; Receipt of Report,

Request for Comments, Solicitation of

Use and Exposure Data

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 37th Report to the

Administrator of the EPA on November

22, 1995. In its 37th Report, which is

included with this notice, the ITC

revised the Priority Testing List by

adding a group of 28 alkylphenols and

alkylphenol ethoxylates to the List for

consideration by the EPA Administrator

for promulgation of test rules under

section 4(a) of the Act. The ITC also

removed 43 previously-recommended

silicone chemicals and 5 isocyanates.

The ITC’s reasons for removing these

chemicals from the List are described in

the 37th Report. As noted in this Report,

the ITC is soliciting use and exposure

data for 9 of the 12 High Production

Volume Chemicals that were

recommended in its 36th Report (60 FR

42982, August 17, 1995) and consumer

use and data for the 10 isocyanates

remaining on the List. There are no

designated or recommended with

intent-to-designate chemicals or

chemical groups in the 37th Report.

EPA invites interested persons to submit

written comments on the Report.

DATES: Written comments on the 37th

ITC Report should be submitted by

March 4, 1996.

ADDRESSES: Comments on the 37th

Report should be submitted to both the

ITC and the TSCA Public Docket. Send

one copy of written submissions to:

John Walker, ITC Director, U.S. EPA

(7401), 401 M St. SW., Washington, DC

20016. Send six copies of written

submissions to: TSCA Public Docket

Office (7407), Office of Pollution

Prevention and Toxics, Environmental

Protection Agency, Rm. B-607 NEM, 401

M St. SW., Washington, DC 20460.

Submissions should bear the document

control number (OPPTS–41044; FRL–

4991–6).

The public record supporting this

action, including comments, is available

for public inspection in Rm. B–607

NEM at the address noted above from

12:00 noon to 4 pm 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., Rm. ET–

543B,Washington, DC 20460, (202) 554–

1404, TDD (202) 554–0551.

SUPPLEMENTARY INFORMATION: EPA has

received the TSCA Interagency Testing

Committee’s 37th 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. The most recent

revisions to this List are included in the

ITC’s 37th Report. The Report was

received by the Administrator on

November 22, 1995, and is included in

this Notice. The Report recommends a

group of 28 alkylphenols and

alkylphenol ethoxylates, removes 43

silicone chemicals and 5 isocyanates

previously recommended for testing and

solicits use and exposure data for 9 High

Production Volume Chemicals (HPVCs)

and 10 isocyanates from the TSCA

section 4(e) Priority Testing List.

II. Status of List

The ITC’s 37th Report requests use

and exposure data for 9 HPVCs and 10

isocyanates, adds 28 chemicals to and

removes 48 chemicals from the Priority

Testing List. The current TSCA section

4(e) Priority Testing List contains 5

chemicals and 9 chemical groups; of

these 3 chemical groups and 3

chemicals were designated for testing.

A notice will be published at a later

date in the Federal Register adding

certain of the substances recommended

in the ITC’s 37th Report to the TSCA

section 8(d) Health and Safety Data

Reporting Rule (40 CFR Part 716), which

requires the reporting of unpublished

health and safety studies on the listed

chemicals. That notice will also add

some of the chemicals to the TSCA

section 8(a) Preliminary Assessment

Information Rule (40 CFR part 712). The

section 8(a) rule requires the reporting

of production volume, use, exposure,

and release information on the listed

chemicals.

III. Electronic and Oral Comments

The EPA invites interested persons to

submit detailed comments on the ITC’s

Report. A record has been established

for this notice under docket number

[OPPTS–41044]. A public version of this

record including printed paper versions

of electronic comments, which does not

contain any information claimed as

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 Nonconfidential Information Center, Rm.

NE–B607, 401 M St., SW., Washington,

DC 20460. Electronic comments can be

sent directly to the ITC at

Walker.johnd@epamail.epa.gov and to the

EPA at:

ncic@epamail.epa.gov

Electronic comments must be

submitted as an ASCII file avoiding the

use of special characters and any form

of ecryption.

The official record for the 37th 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: January 22, 1996.

Charles M. Auer,

Director, Chemical Control Division, Office

of Pollution Prevention and Toxics.

Thirty-Seventh Report of the TSCA

Interagency Testing Committee to the

Administrator, U.S. Environmental

Protection Agency

Summary

This is the 37th 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 28 alkylphenols

and alkylphenol ethoxylates and

removing 43 previously-recommended

silicone chemicals and 5 isocyanates. As

noted in this Report, the ITC is
Federal Register / Vol. 61, No. 23 / Friday, February 2, 1996 / Notices 4189

soliciting use and exposure data for 9 of

the 12 High Production Volume

Chemicals that were recommended in

its 36th Report (60 FR 42982, August 17,

1995) and consumer use and exposure

data for the 10 isocyanates remaining on

the List. 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 1995)

Report Date Chemical/Group Action

26 May 1990 ......... Isocyanates ................................................................... Recommended with intent-to-designate.

27 November 1990 62 Aldehydes ................................................................ Recommended with intent-to-designate.

28 May 1991 ......... Acetone ......................................................................... Designated.

28 May 1991 ......... Thiophenol .................................................................... Designated.

29 November 1991 10 Alkyl-, bromo-, chloro-, hydroxymethyl diaryl ethers Recommended.

30 May 1992 ......... 13 Siloxanes ................................................................. Recommended.

31 January 1993 ... 24 Chemicals with no dermal toxicity data ................... Designated.

32 May 1993 ......... 32 Chemicals with insufficient dermal absorption data Designated.

34 May 1994 ......... White phosphorus ......................................................... Designated.

34 May 1994 ......... Ethyl tert-butyl ether ..................................................... Recommended.

34 May 1994 ......... Tert-amyl methyl ether .................................................. Recommended.

35 November 1994 24 Chemicals with insufficient dermal absorption data Designated.

36 May 1995 ......... 12 High Production Volume Chemicals ........................ Recommended.

37 November 1995 28 Alkylphenols and alkylphenol ethoxylates ............... 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 36 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 membership and

support personnel are listed at the end

of this Report.

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. The 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’’ studies, ‘‘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.

II. 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

Alkylphenols and alkylphenol ethoxylates Recommended ............................................................... 11/95

Butylphenols .

88–18–6 2-tert-Butylphenola

98–54–4 4-tert-Butylphenola.

99–71–8 4-sec-Butylphenola.

1638–22–8 4-n-Butylphenolb.

3180–09–4 2-Butylphenolb.

27178–34–3 tert-Butylphenol (mixed isomers)b

31195–95–6 Isobutylphenol (mixed isomers)b

Pentylphenols

80–46–6 4-tert-Pentylphenola

94–06–4 4-(1-Methylbutyl)phenolb

14938–35–3 4-Pentylphenolb
4190 Federal Register / Vol. 61, No. 23 / Friday, February 2, 1996 / Notices

TABLE 2.—REVISIONS TO THE TSCA SECTION 4(E) PRIORITY TESTING LIST—Continued

CAS No. Chemical Name Action Date

Octylphenols

949–13–3 2-Octylphenolb

1806–26–4 4-Octylphenolb

3884–95–5 2-(1,1,3,3-Tetramethylbutyl)phenolb

27193–28–8 (1,1,3,3-Tetramethylbutyl)phenol (mixed isomers)a,c

1322–69–6

29932–96–5

30105–54–5

62744–41–6

27985–70–2 (1-Methylheptyl)phenol (mixed isomers)b

54932–78–4 4-(2,2,3,3-Tetramethylbutyl)phenolb

Nonylphenols

104–40–5 4-Nonylphenolb

11066–49–2 Isononylphenol (mixed isomers)b

17404–66–9 4-(1-Methyloctyl)phenolb

25154–52–3 Nonylphenol (mixed isomers)a,c

1300–16–9

84852–15–3 Branched 4-nonylphenol (mixed isomers)a

Dodecylphenols

104–43–8 4-Dodecylphenolb

27193–86–8 Dodecylphenol (mixed isomers)a,c

1331–57–3

Octylphenol ethoxylates

2315–66–4 Decaethylene glycol 4-isooctylphenyl etherb

2497–58–7 Hexaethylene glycol 4-isooctylphenyl etherb

9002–93–1 Polyethylene glycol 4-(tert-octyl)phenyl etherb

9036–19–5 Polyethylene glycol mono(octyl)phenyl etherb

68987–90–6 Poly(oxy-1,2-ethanediyl),α-(octylphenyl)-ω-hydroxy-,

brancheda

Silicone Chemicals Remove previously recommended chemicals 11/95

107–50–6 Tetradecamethylcyloheptasiloxane

107–52–8 Tetradecamethylhexasiloxane

107–53–9 Tetracosamethylundecasiloxane

541–01–5 Hexadecamethylheptasiloxane

541–05–9 Hexamethylcyclotrisiloxane

546–56–5 Octaphenylcyclotetrasiloxane

556–68–3 Hexadecamethylcyclooctasiloxane

556–69–4 Octadecamethyloctasiloxane

556–70–7 Docosamethyldecasiloxane

556–71–8 Octadecamethylcyclononasiloxane

999–97–3 Hexamethyldisilazane

2370–88–9 Tetramethylcyclotetrasiloxane

2374–14–3 Trifluoropropylmethylcyclotrisiloxane

2471–08–1 Hexacosamethyldodecasiloxane

2471–09–2 Octacosamethyltridecasiloxane

2471–10–5 Triacontamethyltetradecasiloxane

2471–11–6 Dotriacontmethylpentadecasiloxane

2554–06–5 Methylvinylcyclosiloxane

2627–95–4 Tetramethyldivinyldisiloxane

2652–13–3 Eicosamethylnonasiloxane
Federal Register / Vol. 61, No. 23 / Friday, February 2, 1996 / Notices 4191

TABLE 2.—REVISIONS TO THE TSCA SECTION 4(E) PRIORITY TESTING LIST—Continued

CAS No. Chemical Name Action Date

9004–73–3 Methylpolysiloxane

9006–65–9 Dimethicone

9016–00–6 Polydimethylsiloxane

18766–38–6 Docosamethylcycloundecasiloxane

18772–36–6 Eicosamethylcyclodecasiloxane

18844–04–7 Hexatriacontamethylheptadecasiloxane

18919–94–3 Tetracosamethylcyclododecasiloxane

23523–12–8 Hexatriacontamethylcyclooctadecasiloxane

23523–14–0 Triacontamethylcyclopentadecasiloxane

23732–94–7 Hexacosamethylcyclotridecasiloxane

36938–50–8 Tetratriacontamethylhexadecasiloxane

36938–52–0 Octatriacontamethyloctadecasiloxane

67762–94–1 Dimethylmethylvinylsiloxane

68037–59–2 Dimethylhydropolysiloxane

68607–75–0 Polymethyloctadecylsiloxane

115631–68–7 Siloxanes and silicones, dimethylmethyl 3,3,3-

trifluoropropyld

149050–40–8 Octacosamethylcyclotetradecasiloxane

150026–95–2 Dotriacontamethylcyclohexadecasiloxane

150026–96–3 Tetratriacontamethylcycloheptadecasiloxane

150026–97–4 Octatriacontamethylcyclononadecasiloxane

150026–98–5 Tetracontamethylcycloeicosasiloxane

150026–99–6 Tetracontamethylnonadecasiloxane

150027–00–2 Dotetracontamethyleicosasiloxane

Isocyanates Remove previously recommended chemicals 11/95

102–36–3 3,4-Dichlorophenyl isocyanate

104–71–9 Phenyl isocyanate

104–12–1 p-Chlorophenyl isocyanate

111–36–4 n-Butyl isocyanate

3173–53–3 Cyclohexyl isocyanate

a Chemicals with production or importation volumes > 1 million pounds that are being considered for designation.

b Chemicals with production or importation volumes < 1 million pounds that are being recommended because they are structurally related to

alkylphenols or alkylphenol ethoxylates being considered for designation. c Alternate CAS numbers are listed for these chemicals.

d Listed as dimethylmethyltrifluoropropylsiloxane with no CAS number in ITC’s 30th Report (57 FR 30608, July 9, 1992).

III. Rationale for the Revisions

A. ITC’s Activities During this Reporting

Period

During the 6 months covered by this

Report, the ITC evaluated several

chemical groups. For alkylphenols and

alkylphenol ethoxylates, 1989 and 1993

TSCA production and importation

volume data were reviewed and online

toxicology databases were searched. For

silicone chemicals, unpublished

chemistry, toxicology, use and exposure

data were reviewed; these data were

submitted in response to the ITC’s 30th

Report (57 FR 30608, July 9, 1992). For

the isocyanates recommended in the

ITC’s 26th Report (55 FR 23050, June 5,

1990), published and unpublished

toxicology, use and exposure data were

reviewed.

B. Specific Rationales

1. Recommended chemicals—

Alkylphenols and alkylphenol

ethoxylates—Recommendation.

Alkylphenols and alkylphenol

ethoxylates are being added to the

Priority Testing List to obtain

unpublished TSCA section 8(d) studies

and to determine if these studies meet

U.S. Government data needs.

Rationale for recommendation.

Alkylphenols and alkylphenol

ethoxylates are being recommended to

determine if there are unpublished

studies that contain data to meet the

needs of the Department of the Interior

(DoI), the EPA and other U.S.

Government organizations represented

on the ITC. The ITC wants to review

these unpublished data before

determining if these chemicals should

be designated for testing to meet U.S.

Government data needs. Alkylphenols

and alkylphenol ethoxylates are being

recommended at this time because: (1)

1989 and 1993 TSCA production and

importation volumes are in the

multimillion pound range, (2) releases

to the environment can occur through

wastewater treatment systems and from

agricultural runoff, (3) alkylphenol

ethoxylates can degrade to alkylphenols,

(4) alkylphenols can persist in the

environment and be highly toxic to

aquatic organisms and (5) exposure to
4192 Federal Register / Vol. 61, No. 23 / Friday, February 2, 1996 / Notices

alkylphenols and alkylphenol

ethoxylates may result in estrogenic,

reproductive or other adverse effects.

Supporting information. The

Substructure-based Computerized

Chemical Selection Expert System

(SuCCSES) is used to identify chemicals

with shared substructures and

associated health or ecological effects

and similar TSCA production or

importation volumes (Walker, Refs. 4

and 6). SuCCSES was used to identify

the alkylphenols and alkylphenol

ethoxylates listed in Table 2. As

indicated in Table 2, nine of the

alkylphenols and alkylphenol

ethoxylates have 1989 and 1993 TSCA

production and importation volumes

greater than 1 million pounds and are

being considered for designation. The

ITC is listing alternate CAS numbers for

some of these alkylphenols and

alkylphenol ethoxylates to increase the

possibility of retrieving a study because

it is filed under a different CAS number.

Table 2 also indicates that 19

alkylphenols and alkylphenol

ethoxylates are being recommended

because they are structurally related to

those being considered for designation.

Relevant data from these additional 19

chemicals will be used to predict or gain

insight into the activity of the 9

alkylphenols and alkylphenol

ethoxylates being considered for

designation when no data are available

for those 9 chemicals. The ITC is

recommending structurally-related

chemicals and alternate CAS-numbered

chemicals to increase the possibility of

obtaining unpublished studies on

alkylphenols and alkylphenol

ethoxylates that are related to those

being considered for designation.

Existing U.S. Government data needs.

The ITC has identified several data

needs for alkylphenols and alkylphenol

ethoxylates: (1) chemical composition

(major components and impurities), (2)

environmental fate of components and

impurities and (3) health and ecological

effects, including toxicokinetics and

endocrine-modulating effects.

Completed activities of the ITC, EPA

and alkylphenol manufacturers. The

ITC is aware that for a few alkylphenols

and alkylphenol ethoxylates there are

numerous studies including those

already developed under TSCA section

4 (Talmage, Ref. 3). The ITC is also

aware that for some of these chemicals,

few health effects, environmental fate

and ecological effects data are available.

The ITC reviews of butylphenols,

pentylphenols, octylphenols, and

nonylphenols suggested that these

chemicals had potential to cause

biological effects. Studies by Soto et al.

(Ref. 2), White et al. (Ref. 10) and

Purdom et al. (Ref. 1) suggest that

alkylphenols and alkylphenol

ethoxylates may cause endocrinemodulating effects. Soto et al. (Ref. 2)

reported that nonylphenol and 4-tertbutylphenol caused proliferation of

human estrogen-sensitive MCF7 breast

tumor cells. White et al. (Ref. 10)

reported that 4-octylphenol, 4-

nonylphenol and 4-nonylphenol

diethoxylate were capable of stimulating

vitellogenin gene expression in trout

hepatocytes. Vitellogenin is a protein

synthesized by the liver of oviparous

fish in response to stimulation by

estradiol or estrogenic compounds.

Purdom et al. (Ref. 1) suggested that

alkylphenols or alkylphenol ethoxylates

may have been responsible for elevated

vitellogenin concentrations in fish

exposed to effluents from 15 sewagetreatment works.

The ITC previously designated three

alkylphenols for testing. 2-secButylphenol was designated in the 32nd

Report (58 FR 38490, July 16, 1993). In

response to this designation, the EPA

solicited parties that would be

interested in developing consent

agreements for dermal absorption

testing. The ITC designated 4-(1,1,3,3-

tetramethylbutyl)phenol in its 11th

Report (47 FR 54625, December 3, 1982)

and 2,6-di-tert-butylphenol in its 18th

Report (51 FR 18368, May 19, 1986). In

response to these designations, the EPA

implemented testing and the

alkylphenol manufacturers developed

the TSCA section 4 chemical fate and

aquatic toxicity data. These data have

been published (Walker, Refs. 5, 7, and

8).

The EPA has pursued testing for two

other alkylphenols. The EPA published

a TSCA section 4 notice proposing

reproductive effects and developmental

toxicity testing for dodecylphenol (56

FR 9092, March 4, 1991). The EPA

worked with the alkylphenol

manufacturers to develop chemical fate

and aquatic toxicity data for branched 4-

nonylphenol under a TSCA section 4

Enforceable Consent Agreement/Order

(55 FR 5991, February 21, 1990). These

data for branched 4-nonylphenol have

been published (Walker, Ref. 8).

The TSCA section 8(d) rule that EPA

promulgated for 2-sec-butylphenol did

not require submission of ecological

effects data (59 FR 5956, February 9,

1994). The ITC is recommending that

the EPA amend this rule to require

submission of ecological effects data in

response to the data needs of the DoI

and EPA. In response to the ITC’s

designations of 4-(1,1,3,3-

tetramethylbutyl)phenol and 2,6-di-tertbutylphenol, the EPA promulgated

TSCA section 8(d) rules. The ITC will

include studies that were submitted in

response to these rules in its review of

other unpublished studies that are

submitted in response to the TSCA

section 8(d) rules that the EPA will

promulgate for the other alkylphenols or

alkylphenol ethoxylates listed in Table

2. The ITC is not recommending these

three alkylphenols because TSCA

section 8(d) studies were previously

submitted in response to these

designations.

Related activities. The Organisation

for Economic Cooperation and

Development (OECD) has three of the

recommended and two of the

previously-designated alkylphenols in

its Screening Information Data Sets

(SIDS) program. The recommended

alkylphenols with their sponsoring

countries listed in parentheses are 4-

tert-butylphenol (Japan), nonylphenol

(mixed isomers) (United Kingdom and

United States) and branched 4-

nonylphenols (mixed isomers) (United

Kingdom). The previously-designated

alkylphenols are 4-(1,1,3,3-

tetramethylbutyl)phenol and 2,6-di-tertbutylphenol (both the United States).

The National Toxicology Program has

scheduled branched 4-nonylphenols

(mixed isomers) for a multigeneration

reproductive effects and developmental

toxicity test. The National Academy of

Sciences is planning to review

published data on hormone-related

chemicals in the environment and

alkylphenols is one chemical group for

which they will be reviewing data.

Industry convened the Endocrine Issues

Coalition in 1995 to address scientific

issues related to subtances in the

environment that potentially may

modulate the endocrine system. The

CMA’s Alkylphenols and Ethoxylates

Panel is a member of this Coalition.

2. Removal of chemicals from the

Priority Testing List—a. Silicone

chemicals. Fifty-six 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 (57 FR 30608, July 9,

1992). In response to this

recommendation, the Silicones

Environmental Health and Safety

Council (SEHSC) met with the ITC and

the EPA to discuss unpublished

toxicity, use and exposure data. Most of

the unpublished toxicity and exposure

data were submitted in response to the

TSCA section 8(d) reporting rule that

was promulgated in response to the

ITC’s 30th Report recommendations (58

FR 28511, May 15, 1993) and the

technical amendments to that rule (58

FR 47647, September 10, 1993). All of

the use data and some of the exposure

data were submitted voluntarily to the
Federal Register / Vol. 61, No. 23 / Friday, February 2, 1996 / Notices 4193

ITC by the SEHSC. Interactions with the

SEHSC facilitated information exchange

and data development for a previouslydesignated siloxane,

octamethylcyclotetrasiloxane (Walker

and Smock, Ref. 9). The SEHSC worked

with the ITC and the EPA to develop a

computerized system of physical

properties, effects and use data for the

56 recommended silicone chemicals.

The ITC has used the information in this

system, the TSCA section 8(a)

production and exposure data, and the

information submitted voluntarily by

the SEHSC to determine that, at this

time, 43 of the previously-recommended

silicone chemicals should be removed

from the Priority Testing List (Table 2).

The specific rationales for removing

these chemicals are listed in the

following Table 3.

TABLE 3.—PREVIOUSLY RECOMMENDED SILICONE CHEMICALS BEING REMOVED FROM THE PRIORITY TESTING LIST

CAS No. Chemical Name Removal rationale

999–97–3 Hexamethyldisilazane

9006–65–9 Dimethicone Highly reactive with moisture and therefore difficult to test for health effects

9016–00–6 Polydimethylsiloxane Highly reactive with moisture and therefore difficult to test for health effects

9004–73–3 Methylpolysiloxane

115631–68–7 Siloxanes and silicones, dimethylmethyl 3,3,3-

trifluoropropyla

Synonyms for dimethyl silicones and siloxanes that remains on the Priority

Testing List

67762–94–1 Dimethylmethylvinylsiloxane Site-limited intermediates used in the production of siloxane polymers

68037–59–2 Dimethylhydropolysiloxane Site-limited intermediates used in the production of siloxane polymers

68607–75–0 Polymethyloctadecylsiloxane Siloxane polymers that are consumed in their end use

546–56–5 Octaphenylcyclotetrasiloxane Siloxane that has no commercial sales or applications at this time

2370–88–9 Tetramethylcyclotetrasiloxane Siloxane that has no commercial sales or applications at this time

2374–14–3 Trifluoropropylmethylcyclotrisiloxane Siloxane that has no commercial sales or applications at this time

2554–06–5 Methylvinylcyclosiloxane Siloxane that has no commercial sales or applications at this time

2627–95–4 Tetramethyldivinyldisiloxane Siloxane that has no commercial sales or applications at this time

Linear Siloxanes

107–52–8 Tetradecamethylhexasiloxane (L6)b Siloxanes that are limited to industrial applications and transformed to polymers during processing

541–01–5 Hexadecamethylheptasiloxane (L7) Siloxanes that are limited to industrial applications and transformed to polymers during processing

556–69–4 Octadecamethyloctasiloxane (L8) Siloxanes that are limited to industrial applications and transformed to polymers during processing

2652–13–3 Eicosamethylnonasiloxane (L9) Siloxanes that are limited to industrial applications and transformed to polymers during processing

556–70–7 Docosamethyldecasiloxane (L10) Siloxanes that are limited to industrial applications and transformed to polymers during processing

107–53–9 Tetracosamethylundecasiloxane (L11) Siloxanes that are limited to industrial applications and transformed to polymers during processing

2471–08–1 Hexacosamethyldodecasiloxane (L12) Siloxanes that are limited to industrial applications and transformed to polymers during processing

2471–09–2 Octacosamethyltridecasiloxane (L13) Siloxanes that are limited to industrial applications and transformed to polymers during processing

2471–10–5 Triacontamethyltetradecasiloxane (L14) Siloxanes that are limited to industrial applications and transformed to polymers during processing

2471–11–6 Dotriacontmethylpentadecasiloxane (L15) Siloxanes that are limited to industrial applications and transformed to polymers during processing

36938–50–8 Tetratriacontamethylhexadecasiloxane (L16) Siloxanes that are limited to industrial applications and transformed to polymers during processing

18844–04–7 Hexatriacontamethylheptadecasiloxane (L17) Siloxanes that are limited to industrial applications and transformed to polymers during processing

36938–52–0 Octatriacontamethyloctadecasiloxane (L18) Siloxanes that are limited to industrial applications and transformed to polymers during processing

150026–99–6 Tetracontamethylnonadecasiloxane (L19) Siloxanes that are limited to industrial applications and transformed to polymers during processing

150027–00–2 Dotetracontamethyleicosasiloxane (L20)

Cyclic Siloxanes

541–05–9 Hexamethylcyclotrisiloxane (D3)c Siloxanes that are limited to industrial applications and transformed to polymers during processing

107–50–6 Tetradecamethylcyloheptasiloxane (D7) Siloxanes that are limited to industrial applications and transformed to polymers during processing
4194 Federal Register / Vol. 61, No. 23 / Friday, February 2, 1996 / Notices

TABLE 3.—PREVIOUSLY RECOMMENDED SILICONE CHEMICALS BEING REMOVED FROM THE PRIORITY TESTING LIST—

Continued

CAS No. Chemical Name Removal rationale

556–68–3 Hexadecamethylcyclooctasiloxane (D8) Siloxanes that are limited to industrial applications and transformed to polymers during processing

556–71–8 Octadecamethylcyclononasiloxane (D9) Siloxanes that are limited to industrial applications and transformed to polymers during processing

18772–36–6 Eicosamethylcyclodecasiloxane (D10) Siloxanes that are limited to industrial applications and transformed to polymers during processing

18766–38–6 Docosamethylcycloundecasiloxane (D11) Siloxanes that are limited to industrial applications and transformed to polymers during processing

18919–94–3 Tetracosamethylcyclododecasiloxane (D12) Siloxanes that are limited to industrial applications and transformed to polymers during processing

23732–94–7 Hexacosamethylcyclotridecasiloxane (D13) Siloxanes that are limited to industrial applications and transformed to polymers during processing

149050–40–8 Octacosamethylcyclotetradecasiloxane (D14) Siloxanes that are limited to industrial applications and transformed to polymers during processing

23523–14–0 Triacontamethylcyclopentadecasiloxane (D15) Siloxanes that are limited to industrial applications and transformed to polymers during processing

150026–95–2 Dotriacontamethylcyclohexadecasiloxane (D16) Siloxanes that are limited to industrial applications and transformed to polymers during processing

150026–96–3 Tetratriacontamethylcycloheptadecasiloxane

(D17)

Siloxanes that are limited to industrial applications and transformed to polymers during processing

23523–12–8 Hexatriacontamethylcyclooctadecasiloxane

(D18)

Siloxanes that are limited to industrial applications and transformed to polymers during processing

150026–97–4 Octatriacontamethylcyclononadecasiloxane

(D19)

Siloxanes that are limited to industrial applications and transformed to polymers during processing

150026–98–5 Tetracontamethylcycloeicosasiloxane (D20) Siloxanes that are non-isolated components of dimethyl siloxanes

a Listed as dimethylmethyltrifluoropropylsiloxane with no CAS number in ITC’s 30th Report (57 FR 30608, July 9, 1992).

b L followed by a number refers to the number of repeating dimethyl siloxanes in a linear chain.

c D followed by a number refers to the number of repeating dimethyl siloxanes in a cyclic chain.

There are 13 siloxanes remaining on

the Priority Testing List as shown in the

following 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 Dodecamethylcyclohexasiloxane (D6)

69430–24–6 Cyclopolydimethylsiloxane (Dx)

Linear Siloxanes

107–46–0 Hexamethyldisiloxane (L2)

107–51–7 Octamethyltrisiloxane (L3)

141–62–8 Decamethyltetrasiloxane (L4)

141–63–9 Dodecamethylpentasiloxane (L5)

Phenyl Siloxanes

68083–14–7 Dimethyldiphenylsiloxanea

Polymers

63148–62–9 Dimethyl silicones and siloxanesa

9006–65–9

9016–00–6

67762–90–7 Dimethyl silicones and siloxanes, reaction products with silica

68037–74–1 Dimethylmonomethylpolysiloxanes
Federal Register / Vol. 61, No. 23 / Friday, February 2, 1996 / Notices 4195

TABLE 4.—SILOXANES REMAINING ON THE PRIORITY TESTING LIST—Continued

CAS No. Chemical Name

70131–67–8 Dimethyl silicones and siloxanes hydroxy terminated

aAlternate CAS numbers are listed for this chemical.

b. Isocyanates.

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). The ITC is

removing 5 more isocyanates from the

List in this Report (Table 2). 3,4-

Dichlorophenyl isocyanate and pchlorophenyl isocyanate are being

removed because 1993 production

volumes were less than 10,000 pounds.

Phenyl isocyanate is being removed

because 1993 production volumes were

less than 1,000,000 pounds and there

are no currently identified U.S.

Government data needs. n-Butyl

isocyanate and cyclohexyl isocyanate

are being removed because there are no

currently identified U.S. Government

data needs.

IV. Activities Related to PreviouslyRecommended Chemicals

A. High Production Volume Chemicals

The ITC solicited use and exposure

data for 12 High Production Volume

Chemicals (HPVCs) in its 36th report (60

FR 42982, August 17, 1995) and

suggested a 60–day submission deadline

from the FR publication date (October

17, 1995). In response to that

solicitation, the ITC received a

September 15, 1995, submission from

Eastman Chemical Company for

diethylene glycol monoethyl ether

acetate (CAS No. 112–15–2), a

September 19, 1995, offer from the

Zeneca Corporation to provide use and

exposure data for trichloromethane

sulfenyl chloride (CAS No. 594–42–3)

and an October 12, 1995, submission

from Ferro Corporation for diethylene

glycol dimethyl ether (CAS No. 111–96–

6). The ITC will review the use and

exposure data for these three HPVCs.

The ITC appreciates these timely

responses and encourages the

manufacturers, processors, and users of

the other nine HPVCs to contact the ITC

with offers to provide use and exposure

data.

B. Isocyanates

The ITC is soliciting consumer use

data for the nine diisocyanates

remaining on the Priority Testing List

(Table 5). The data are being solicited to

address the information needs of the

Consumer Product Safety Commission

(CPSC). For several of these isocyanates,

the ITC is continuing its review of

exposure, health effects and chemical

fate information, including information

based on structure-activity relationships

(SARs), in response to concerns of the

Department of Defense (DoD) and the

EPA.

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). As noted above in section

III(B)(2)(b) of this ITC Report, 33 of

these isocyanates have been removed

from the Priority Testing List. The 10

remaining isocyanates are listed in the

following Table 5.

TABLE 5.—ISOCYANATES REMAINING ON THE PRIORITY TESTING LIST

CAS No. Chemical Name

Monoisocyanate

329–01–1 (α,α,α-Trifluoro-m-tolyl)isocyanate

Diisocyanates

91–08–7 2,6-Toluene diisocyanate (2,6-TDI)

101–68–8 4,4′-Diphenylmethane diisocyanate (MDI)

584–84–9 2,4-Toluene diisocyanate (2,4-TDI)

4035–89–6 Tris(isocyanatohexyl)biuret

4098–71–9 Isophorone diisocyanate

5124–30–1 1,1’-Methylenebis(4-isocyanatocyclohexane)

5873–54–1 1-Isocyanato-2-((4-isocyanatophenyl)methyl)benzene

26447–40–5 1,1’-Methylenebis(isocyanatobenzene)

26471–62–5 Toluene diisocyanate (80% 2,4-TDI; 20% 2,6-TDI)

For these 10 isocyanates, the ITC is

reviewing data on 1993 TSCA

production and importation volumes, as

well as published and unpublished

(TSCA section 8(d), 8(e), FYI, etc.) data

on physical and chemical properties,

environmental fate and releases, health

effects, occupational exposures and

uses. For each of these isocyanates, the

ITC is monitoring ongoing testing,

including any testing that might be

considered by the International

Isocyanates Institute, the CMA or the

OECD.

At this time, the ITC has determined

that there are insufficient consumer use

and exposure data to permit an accurate

assessment of exposure or the need for

additional testing of the diisocyanates

listed in Table 5. The ITC is soliciting

consumer use data on these as well as
4196 Federal Register / Vol. 61, No. 23 / Friday, February 2, 1996 / Notices

any other commercially relevant

diisocyanates (e.g., hexamethylene

diisocyanate, CAS No. 822–06–0).

Information on the presence of

diisocyanates in commercially available

products is needed as well as

information on exposures that result

from their use. The following specific

information is solicited:

• Category of products in which

diisocyanates (all forms) are present,

such as rigid and flexible foams,

coatings, and adhesives

• Specific diisocyanate present, by

product category

• Chemical form of the diisocyanate

(monomer, prepolymer, oligomer,

polymer, etc.)

• Weight fraction of diisocyanate in

the product and the relative amount of

the different diisocyanate forms,

particularly free monomer, oligomer,

and prepolymer (a rough range of

weight fraction is sufficient)

• Percent of total manufactured/

imported volume (rough estimate is

sufficient)

• Form of the product (liquid, aerosol,

foam, etc.)

• General application of the product

(sealant, paint, adhesive, insulation,

etc.)

• Air monitoring or exposure

simulation data for diisocyanates

resulting from use of any of the

indicated product categories

References

(1) Purdom, C.E., Hardiman, P.A., Bye, V.J.,

Eno, N.C., Tyler, C.R., and Sumpter, J.P.

Estrogenic effects of effluents from sewage

treatments works. Chemical Ecology. 8:275–

285 (1994).

(2) Soto, A.M., Justicia, H., Wray, J.W., and

Sonnenschein, C. p-Nonylphenol: an

estrogenic xenobiotic released from

‘‘modified’’ polystyrene. Environmental

Health Perspectives. 92:167–173 (1991).

(3) Talmage, S.S. Environmental and

human safety of major surfactants: Alcohol

ethoxylates and alkylphenol ethoxylates. A

report to the Soap and Detergent Association.

Lewis Publishers, Boca Raton, FL (1994),

374pp.

(4) Walker, J.D. Chemical selection by the

TSCA Interagency Testing Committee: Use of

computerized substructure searching to

identify chemical groups for health effects,

chemical fate and ecological effects testing.

Sci. Total Environ. 109/110:691–700 (1991).

(5) Walker, J.D. Review of ecological effects

and bioconcentration testing recommended

by the TSCA Interagency Testing Committee

and implemented by EPA under the Toxic

Substances Control Act: Chemicals, tests and

methods. pp. 92–115. In W.G. Landis, J.S.

Hughes and M.A. Lewis (eds.),

Environmental Toxicology and Risk

Assessment, ASTM STP 1179. ASTM,

Philadelphia, PA (1993).

(6) 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. Toxicol. Model.

1:123–141 (1995a).

(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-tertbutylphenol, ethyl benzene, brominated

flame retardants, phthalate esters,

chloroparaffins, chlorinated benzenes and

anilines. In T.W. LaPoint, F.T. Price, and E.E.

Little (eds), Environmental Toxicology and

Risk Assessment: Fourth Volume, ASTM STP

1262, ASTM, Philadelphia. In Press (1995b).

(8) Walker, J.D. Recommendations of the

TSCA Interagency Testing Committee:

Aquatic toxicity, bioconcentration and

chemical fate data developed under section

4 of the Toxic Substances Control Act. pp.

669–701. In G.M. Rand (ed), Fundamentals of

Aquatic Toxicology II, Taylor Francis

Publishers, Washington, DC (1995c).

(9) Walker, J.D. and W.H. Smock.

Chemicals recommended for testing by the

TSCA Interagency Testing Committee: A case

study of octamethylcyclotetrasiloxane.

Environmental Toxicology and Chemistry

14:1631–1634 (1995).

(10) White, R., Jobling, S., Hoare, S.A.,

Sumpter, J.P., and Parker, M.G.

Environmentally persistent alkylphenol

compounds are estrogenic. Endocrinology

135:175–182 (1994).

TSCA Interagency Testing Committee

Statutory Organizations and Their

Representatives

Council on Environmental Quality

Brad Campbell, Member

Department of Commerce

Edward White, Member

Environmental Protection Agency

David R. Williams, Member

Lois Dicker, Alternate

National Cancer Institute

Victor Fung, Member

Harry Seifried, Alternate

National Institute of Environmental Health

Sciences

Errol Zeiger, Member, 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 Rice, Member

Department of Defense

David A. Macys, Member

Department of the Interior

Barnett A. Rattner, Member, Vice Chair

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, Ph.D, M.P.H.,

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:

walker.johnd@epamail.epa.gov

[FR Doc. 96–1721 Filed 2–1–96; 8:45 am]

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