318 Federal Register I Vol. 54. No. 6 I Tuesday. January 10, 1969 / Rules and Regulations

reducing this burden, to Chief,

Information Policy Branch, PM—223, U.S.

Environmental Protection Agency, 401 M

St., SW., Washington, DC 20480; and to

the Office of Information andRegulatory

Affairs, Office of Management and

Budget. Washington, DC 20503.

I. ITC Recommendation

ENVIRONMENTAL PROTECTION

AGENCY

40 CFR Part 799

[OPTS-420710 FRL-3503-6J

Testing Consent Order for

Octamethy$cyclotstra.lIoxans

AGENCY’. Environmental Protection

Agency (EPA).

ACTION: Final Rule.

SUMMA~VtThis rule announces that EPA

has signed an enforceable testing

consent order with six manufacturers of

octamethylcyclotetrasiloxane (OMCTS~

CAS No. 55O.-87—Z~,who have agreed to

perform certain chemical fate and

environmental effects testswith

OMCTS. OMCTS is added to the list of

Testing Consent Orders in 40 CFR

799.5000 for which the export

notification requirements of 40 CFR Part

707 app~,,r.

EFFI~W~DATE January IA 1989.

RM~ U~NAT~NCOIflAC1~

Michael M. StahL Ac~ia~Director, TSCA

Asaiet*~c~Office~TS-79o),Office of

Toxic Substances, Rxn. EB-4&. 401 M St.,

SW., Washington.DC 20460, (202) 554-

1404.

SUP9L~IWTAR~INPOeMATIO~Under

procedures described in 40 CFR Part 7~

six manufacturers have entered into a

testing consent order with EPA in which

they have agreed to perform certain

chemical fate and environmental effects

tests with OMC~FS.

Public reporting burden for this

collection of information is estimated to

average 8 hours per response, including

time for reviewing instructions,

searching existing data sources,

gathering and maintaining the data

needed, and completing andreviewing

the collection of information. Send

comments regarding the burden estimate

or any other aspect of this collection of

information, including suggestions for

In its 15th Report to EPA. published in

the Federal Registerof November 29,

1984 (49 FR 46931) the ITO

recommended that OMCTS be

considered for chemical fate and

environmental effects testing. Chemical

fate testing included water solubihty.

octanol/water partition coefficient. and

biodegradation studies. The

recommended environmental effects

testing included acute toxicity testing

with several species and, if indicated by

the results of the acute tests, chronic

toxicity tests with appropriate species.

II. Proposed Test Rule

In the Federal Register of October 30,

1985 (50FR 45123), EPA issued a

proposed test rule requiring that

manufacturers and processors of

OMCTS conduct chemical fate and

environmental effects testing of

OMCTS. Chemical fate testing included

biodegradability testing in water and

sediment using the eco~~coremethod of

Bourquin et al. (Ref. 1), aerobic and

anaerobic biodegradability tests in soil,

and a biodegradability test in a sludge

system. Environmental effects testing

included acute toxicity tests with

rainbow trout, fathead minnow, bluegilL

sheepahead minnow, silversides,

daphnids, mysId shrimp. oyster, and

freshwater and saltwater algae; chronic

effects tests with a fish, daphnid, and

mysid shrimp; bioconcentration tests

with fathead minnows and oysters; a

marine sediment toxicity test and a

reproduction test with mallard ducks.

EPA based this testing on a finding of

potential for unreasonable risk of injury

to the environment under TSCA section

4(a)(1)(A) and a finding ofsubstantial

environmental exposure under section

4(a)(1)(B~.These finds are more fully

described in the proposed rule.

ill. Testing Consent OrderNegotiations

After issuing the proposed test rule on

OMCTS. EPA amended the regulations

for rulemeking to expedite the

developmentof data for risk assessment

by establishing the TSCA section 4

testing consent orderprocess. A consent

order is not based on formal findings

and expedites testing while retaining the

same TSCA penalty provisions

applicable under rulemaking.
Federal Register I Vol. 54. No.6 I Tuesday. January 10. 1989 I Rules and Regulations 819

On March 18. 1988. the Silicones

llealth Council (SI-IC) submitted a

proposal to EPA requesting EPA to

develop a testing consent order for

OM~TS(Ref. 2). The SHC proposal

contained r.~ostof the testing that EPA

had included in the proposed rule. EPA

agreed to consider negotiating a consent

order with the SHC and issued a notice,

published in the Federal Register on

April 8. 1988 (53 FR 11341). announcing

the decision. This notice also announced

the time and location of a public meeting

to initiate testicg negotiations on

OMCTS and requested that all

“interested p.irties who wanted to

participate in negotiations identify

themselves to EPA by April 28. 1988.

Prior to the public meeting of April 20.

1988 the SI-IC drafted a consent order on

OMCTS and submitted it to EPA for

review (Ref. 3). This draft was modified

by EPA and was discussed at the public

meeting of April 20 and a revised draft

was discussed at the meeting of May 11.

By December 1. 1988, six OMCTS

manufacturers: Dow Corning Corp..

UnionCarbide Corp., General Electric

Co., Rhone-Poulenc Inc., Mobey Corp..

and Wacker Silicones Corp.. and two

interested parties, the Silicones Health

Council and the County of Onondaga.

New York had signed theTesting

Consent Order for OMCTS. The

manufacturers agreed to perform certain

chemical fate and environmental effects

tests by specified dates according to the

test standards in the Appendix of the

Consent Order.

IV. Use and Exposure

OMCTS is a colorlessoily liquid with

a water solubthty olapproxnnately 50

ppb, a log soil-sorption coefficient of

4.45, a log octanol/water pertitfon

coefficient of 3.8. and avapor pressure

of 1 mm Hgat 20CC (Refs. 4 through 1Q.

Based on data submitted under

section 8(a) of TSCA and by Dow

Corning, the 1985 iinportation/

production volume of OMCTS was 110

to 135 million pounds and is expected to

increase about 10 percent per year (Ref.

10). Approximately 80 percent of the

OMCTS produced or imported is used

on-site as an intermediate in the

production of polydimethylsiloxane

polymers (Ref. 9 through 12). These

polymers are used in making

surfactants, propellants, lubricants.

caulks. sealants. and rubber products

(Refs. 9. 11, and 12). The remaining 20

percent of OMCTS is used in spray

cleaners and polishes, in paper and

textile sizing agents. in detergents. as a

defoamer in inks and paints, and in

cosmetic products such as colognes.

hairsprays. and antiperspi.rants (Refs. 11

and 13).

The proposed rule on OMCTS

included the results of several

monitoring studies reporting the

presexu~of organosillcones in rivers

and estuaries. effluents, sludges. and

sediments at several locations in the

United States,Europe, and Japan. After

publication of theproposed test rule, the

SHC submitted theresults of a

monitoring study it had sponsored (Ref.

14). In this study, 15 sedimentsamples

from 3 estuaries and 8 sediment samples

from4 freshwater sites were analyzed

for OMCFS and or’genosilicon. Effluent

and sludge samples from 3 waste water

treatment plants were also analyzed.

Organosthcon was foundin 17 of 28

samples. but OMCTS was identified in

only Isedin~ntsample from the Rouge

River, Detroit, and in 2 sludge cake

samples. EPA has reviewed this study,

and, although locations below

manufacturing p’ants were not sampled,

thestudy is sufficientto show that

OMCTS is not a widespread

environmental contaminant at

concentrations exceeding 50 ppb.

V. Testing Program

.4. Chemical Fate

SHC has reported that OMCTS is not

biodegradable in water and sediment.

but due to its volatility, will not persist

in receiving waters and sediments (Ref.

15).

Under the Consent Order, the

manufacturers have agreed to determine

the solubility of OMCTS in freshwater

and saltwater, its volatility half-life in

freshwater and saltwater, and its

biode~adabilityrate in a sediment/

water system.

B. En iironmen tatEffects

Several acute toxicity tests were

summarized in the proposed rule. EPA

judged all the test data inadequate

because they were based on nominal

test concentrationsthat exceeded the

water solubility of OMCTS. Available

bioconcentration data indicate that the

bioconcentration factor for OMCTS in

fish may be as high as 10.000.

On February 10, 1988. Dow Corning

Corporation submitted the results of a

recently completed daphnid chronic

toxicity test with OMCTS to EPA under

section 8 (d) and (e) of TSCA (Ref. 18).

These data suggested that OMCTS w~

toxic to daphnids at a concentratioc

low as 10 ppb. Since similar adverse~

effects were seen in the daphnids

exposed to the solvent control. EPA and

Dow Corning consider these data

unreliable and inadequate to assess the

toxicity of OMCTS.

In the Consent Order, the

manufacturers agreed to a tiered testing

program. Tests agreedupon are

presented in thefollowing table.

TABLE.—TESTING PtAN FOR OUCTS

Iesme I Stal R~od~,

nsrlTNts

Sotut*ty lest a~fresh w~.... ._ - - ....,.._ .~..

SOlubNity test in salt ~ - .. .... .~....... . .. ~.

-——,.-* -........-----—--.

Aquatic biodegradation ~ ..._.___.....

40 CFR ~ 8

40 CER 796.1860....... ~ 8

~ili~~ ._ - ~ 8

Bcaiqi~ - - 12

40 CFR 797.1050 12

40 CFR 797 1300 .~..... .. 12

40 C~R797M00 12

4fl.CF~~ 12

40 CFR 797.19 ~ 12

40 CFR 797.1330 - -~ 12

40 CFR 797 1520 12

10

10

10

18

16

16

16

16

16

16

16

Acute toxicity, algae ........._.__~_...

Acute toiocity. ~ .. ..._....~..._

Acute toxic~y,r~’ibowtrout .. - ...._. ........

Acute badly, silyei~id.~ aflespafleed iy*w~.... .. ~.. .. ~

ActS. ~ mysatV_._.....__._....

Chronic toaaby, ~ ..

Bioconcentration, tathead mira~........ .._..._,,... - .._....._..~..

T~I T.st*~

Fish early ble stage test - ~__....

Sedimenl/in’eertebraee teat - ...... ,.._._...... ..

41) CFR 797 1600 .... 19

Aaa~na‘ .. ..... IS

24

24

Months afterthe e6ei~i~.date.
Federal Register / Vol. 34, No. 6 / ruesday. January 10. 1989 / Rules dud Regulations

Smith, J.H. Bornoerger. DC Jr.. arid Haynes. DL. “Prediction of me ~olatilzatiorrrates 04 high-volatility cire’ncals trom natural water 000.es.” E’”ia,,,n~”.~

Sc’ence and Technology 14:1302-1337 11980).

Bourquin, A.W., Hood, MA., arid Garnas, 93. “An artificial microbial ecosystem br determining effects and ate ot tosicants in a salt~rnarshenveonorerrt.”

Deve/opm~ntsin /r1dijstna~A robro/cgy t8’195..191. (1977).

Pecformed only 4 any LCSO from Tier 5 <1 mg/I or the MAIC from the da~hrudchronic test is ‘.0.1 mg/I.

Adams. W J., Kn’teffe. P A.. and Mosher, R.~3.“Aquatic safety assessment at chemicals sorbed to sediments.” ri’ “Aquatic Toxicology and Hazard

Assessrrient’ Sexenuti SvrnooCum. ASTM SIP 654 9.0 Caidwell, P. °urcly,arid PC. Bahner, Eds.. American Society or Testing and Materials. Phifadeiptiia. PA, ~g.

429-453, (1965)

In tierI, the manufacturers will

perform all the required chemical fate

tests, the acute tests with algae,

daphn:d. rainbow trout, a marine fish,

and rnysid shrimp, and a

bioconcentration test with fathead

minnows, and will repeat the chronic

toxicity test with daphnids. Tier II

testing includes a fish early life stage

toxicity test and a test to determine

sediment toxicity to benthic

invertebrates. Tier II tests will be

performed only if any of the LC5O’s from

the tier I tests are i~1mg/I. or the

maximum acceptable toxicant

concentration (MATC) from the daphnid

chronic test is ~0.1mg/I. If no such

adverse effects are observed in any of

the tier I tests, tier II testing is nut

required,

EPA is not requiring that the

manufacturers perform all the acute

tests that were identified in the

proposed rule. EPA believes that if acute

toxicity is observed, data on five species

are sufficient to assess the acute toxicity

of OMCTS to aquatic organisms. EPA is

not including a mysid chronic test in tier

11 because EPA believes that both the

toxicity data from the daphnid life cycle

test, and, if triggered, the fish early life

stage test and the sediment test with the

midge, will be sufficient to assess the

chronic toxicity of OMCTS.

EPA is not requiring a reproduction

test in mallard ducks because available

health effects data demonstrate that

OMCTS is not toxic to mammals, and

thus is not expected to be toxic to ducks.

The rat oral LC5O is >2.0 g/kg and

antifoam A (5 percent OMCTS) had no

adverse effects on rats in a 2-year

feeding study (Ref. 17).

The manufacturers agreed to perform

the testing according to dted EPA test

standards and a specified test schedule.

Tier I testing will he completed in 16

months with interim statua reports due 6

and 12 months after the date of

publication of this notice. If tier 11 testing

is required, it will be completed in 24

months with an interim status report due

after 18 months.

EPA and the manufacturers recognize

that OMCTS is a volatile substance that

is soluble in water at extremely low

concentrations and that a test method

does not exist to measure OMCTS at

concentrations below 30 ppb. Also.

additional efforts are needed to develop

test systems that can generate stable

concentrations of OMCTS in water. The

manufacturers will work on the

development ofsuch methods and test

s~.stemsduring the period after

signature of the Consent Order and

before the first test in tier I is performed.

EPA will use the data generated by

these tests to determine the risk of

adverse environmental effects

associated with the manufacture, use.

and disposal of OMCTS.

VI. Export Notification

The issuance of this Testing Consent

Order subjects any personwho exports

or intends to export OMCTS to the

export notification requirements of

section 12(b) of TSCA. The specific

requirements are listed in 40 CFR Part

707. In 52 FR 23548 ofJune 23. 1987, EPA

issued 41) CFR 799.5000 as a listing of

testing consent orders issued by EPA.

This listing serves as notification to

persons who export or who intend to

export chemical substances or mixtures

which are thesubject oftesting consent

orders that 40 CFR Part 707 applies.

VII. Rulemaking Record

EPA has established a record for this

rule (docket number OPTS—42071B). This

record contains the information EPA

considered in developing this rule and

the Consent Order and includes the

following informetion~

A. Supporting Documentation

(I) Testing Consent Order for OMCTS.

(2) Federal Register notices pertaining

to this rule and Consent Order

consisting of:

(a) Notice containing the ITC

designation of OMCTS to the Priority

List (49 FR 46931; November 29. 1984).

(b) Rules requiringTSCA section 8(a)

and 8(d) reporting on OMCTS (49 FR

46739 and 46741: November 28, 1984).

(c) Notice of EPA’s proposed test rule

for octamethylcyclotetrasiloxane (50 FR

45123: October 30, 1985).

(d) Notice soliciting interested parties

for developing a Testing Consent Order

for OMCTS (53 FR11341: April 8, 1988).

(3) Communications consisting ot~

(a) Written letter.

(b) Contact reports of telephone

conversations.

(c) Meeting summaries.

(4) Reports—published and

unpublished materials.

8. References

1) Bourquin. A.W.. Hood. MA.. .tzid

Garnas. RI. “An artificial microbial

ecosystem For determining effects and fate of

toxicants in a salt-marsh enviroirmi-nt.”

Dc to/opmer’t ‘ri Industrial l.ticmho lacy.

18:185—191. (1977).

0) Silicones Health Council, Leitur from

E.). Hobbti to Siephen E11~.Envlrinrto’ntdl

Protection Agency. (March 18. 1988).

(3) Silicon’s Health Council, Drift l’eatlng

Consent Order on OMCTS. (April 13. 1988).

(4) Dow Corning Corporation. Leiter with

attai,hed studies tram Cecil L Frye to Martha

G. Price, Environmental Protection Ai,’ericy.

(December 12, 1984).

(5) Vogel. G.E. and SL,rk. F 0. “Mutual

solubilities in water’permethylsiloi.ane

system.” Journal of C’hemical Engirocrtnc

Data. 9(4):555—601. (October 1984).

(6) Bruggemen, WA. et a). ‘~Absorpttonarid

retention of polydimethylsiloxanes

(Silicone~)in fish: preliminary experiments.”

Toxicology arid Environmental Chervistty.

7)41:287—296. (1984).

(7) Dow Coming Corporation. Unpublished

study of T.H. Lane and Cl. Frye. Letter with

attached studies from Cecil L Frye to Martha

G. Price. Environmental Protection Agency.

(December 12. 1984).

(8) Kenaga. E.E.. “Predicted

bioconcentration factors andaoild sorption

coefficients of pesticides andother

chemicals.” Ecotoxicology and

Environmental Safety, 4:26—38. (1980).

(9) Interagency Testing Committee (ITC).

Fifteenth Report to the Administrator and

Request for Comments. (November 29. 1984).

(10) Dow Coming Corporation. Latter with

attachment from C.W. Lentz to Martha Price,

Environmental Protection Agency. (February

27. 1986,.

(11) Dow Corning Corporation. Letter with

attached studies from E.. Hobbs to M. Grief,

Interagency Testing Committee. (December

16.1982).

(12) Browning. G.R. Silicone Products

Diviaion. General Electric Co. Per~onat

communication with M.G. Price, U.S.

Environmental Protection Agency. (May 23.

1965).

(13) Versar, Inc. Environmental risk

assessment for octamethaylcyclotetraslloxane. Springfield, VA (1986).

(14) Ann Arbor Technical Services. Inc.

Organoailoxanes in fresh water andsaLt

water sediments. Ann Arbor, MI. (1985).

(15) Silicones Health Council. Comments of

the Silicones Health Council on EPA’s

proposed test rule for

octamet.bylcyclotetrasiloxane. (February 28.

1986).

(‘16) Dow Coming Corporation. A chronic

reproductive limit teat of polyeth~(eneglycol

sorbitan monolaurato and
Federal Register / Va). 54. No. 6 I Tuesday, January 10, 1989 I Rules and Regulations 621

octamethv:i.vi;i&,ti’tr.isj(is.ini’ with Diiphuia

aiut.’na, iqttttj

17) CRCS. mi. l::farmatain Restew No.

.~48.0ctamothvlc~i,lotetrasiloxane, Reston.

VA (May 31, 1983(.

A public version of thisrernrd is a~ai(able

for inspection in the OPTS Reading Rm. NE—

G004. 401 M St. SW, Washington. DC. from 8

am, to 4 p.m. Monday throu~thF~id~yexcept

legal holidays.

VIII. OtherRegulatory Requirements

The information collection

requirements contained in this rule have

been approved by the Office of

Management and Budget (0MB) under

the provisions of this Paperwork

Reduction Act. 44 U.S.C. etseq. and

have been assigned 0MB control

number 2070—0033.

Public reporting burden for this

collection of information is estimated to

average 8 hours per response. including

time for reviewing instructions.

searching existing data sources.

gathering and maintaining the data

needed. and completing and re~iewing

the collection of information.

Send comments regarding the burden

estimate or any other aspect of this

collection ofinformation, including

suggestions for reducing this burden, to

Chief. Information Policy Branch, PM—

223. U.S. Environmental Protection

Agency. 401 M St.. SW., Washington. DC

20460: and to the Office of Information

and Regulatory Affairs, Office of

Management and Budget. Washington.

DC 20503, marked “Attention: Desk

Officer for EPA.”

List of Subjects in 40 CFR Part 799

Testing procedures,

Environmental protection.

Hazardous substances,

Chemicals,

Chemical export,

Recordkeeping and reporting

requirements.

Dated: December 28, 1988.

Susan F. Vogt,

Acting .tssistant .4dministrntor,~orPi’~ru.alei.

and Toxic Substances.

PART 799—(AMENOEDJ

Therefore. 40 CFR Part 799 is

amended as follows:

1. The authority citation cOntinues ,

read as follows:

Authority: 15 t’,S.C. 2603. 2811. 2623.

2. Section 799.5000 is amended hv

adding the following chemical substani:e

in Chemical Abstract Service (CAS)

Registry Number order to the tahle to

read as follows:

§ 799.5000 TestIng consent orders.

CA.S No. -~ S~tmianc.or nsxti,e nwt. Testing Fad~~~~ss*er

558-57-2 0ctametPiy$cyc~-tetrs.5axan. _.___~._._....... CbsaIcl t~u....... _...~ ... .. ...... ... [Insert FR debt.

~ ~ .. ..._.,.,. (insert FR datel

(FR Dec. 89—298 Filed 1—9-89: 8:45 am)

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