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 ProtectionAgency, 401 M St., SW., Washington, DC 20480; and to the Office ofInformation andRegulatory Affairs, Office ofManagement 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~Vt

This rule announces that EPA has signedan enforceabletesting consent orderwith 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 listof Testing Consent Orders in 40 CFR 799.5000 for which theexport notificationrequirements of40 CFRPart 707 app~,,r. EFFI~W~

DATEJanuary IA 1989. RM~ U~NAT~N COIflAC1~ MichaelM. 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 haveentered into a testing consentorder 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 ofinformation is estimated to average 8hours perresponse, including time for reviewinginstructions, searching existing data sources, gatheringand maintaining the data needed, andcompleting andreviewing the collectionofinformation. Send commentsregarding the burden estimate
or any otheraspect ofthis collectionof 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, ifindicated by the results ofthe acute tests, chronic toxicity tests with appropriate species.
II.Proposed TestRule
In the Federal Register ofOctober 30, 1985 (50FR 45123), EPA issued a proposed test rule requiringthat 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~~core method of Bourquin et al. (Ref. 1), aerobic and anaerobicbiodegradability 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 saltwateralgae; 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 ofinjury to the environment underTSCA 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 proposedrule.
ill. Testing Consent OrderNegotiations
Afterissuing the proposed test rule on OMCTS. EPA amended the regulations for rulemeking to expedite the developmentofdata for risk assessment by establishing the TSCA section 4 testingconsent orderprocess. A consent order is not based on formal findings and expedites testing whileretaining the

sameTSCA penalty provisions applicableunder 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.~ost

ofthe testing that EPA had included in the proposedrule. 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 ofa 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 ofApril 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 ofApril 20 and arevised draft

was discussed at the meeting ofMay 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 Orderfor OMCTS. The manufacturers agreed to perform certain chemical fate and environmental effects tests by specified dates according tothe test standards in the Appendix ofthe Consent Order. IV. Use and Exposure OMCTS is a colorlessoily liquid with
a watersolubthty olapproxnnately 50 ppb, alog soil-sorption coefficient of 4.45, a log octanol/waterpertitfon coefficient of 3.8. and avapor pressure of 1 mm Hgat 20CC (Refs. 4 through 1Q. Based on data submitted under section 8(a) ofTSCA and by Dow Corning, the 1985 iinportation/ production volume ofOMCTS was 110 to 135 million pounds andis expected to increase about 10 percent per year (Ref. 10). Approximately 80 percent ofthe OMCTS produced or imported is used on-site as an intermediate in the production ofpolydimethylsiloxane 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 ofOMCTS is used in spray cleaners and polishes, in paper and textile sizing agents. in detergents. as a defoamerin inks and paints, and in cosmetic products such as colognes. hairsprays. and antiperspi.rants (Refs. 11 and 13). The proposedrule on OMCTS included the results of several monitoring studies reporting the presexu~

of organosillcones inrivers and estuaries. effluents, sludges. and sediments at several locations in the United States,Europe, andJapan. After publication oftheproposed test rule, the SHC submitted theresults of a monitoring study ithad sponsored (Ref. 14). In this study, 15 sedimentsamples from 3 estuaries and 8 sediment samples from4 freshwatersites were analyzed for OMCFS andor’genosilicon. Effluent and sludgesamples from 3 waste water treatment plantswere also analyzed. Organosthconwas foundin 17of28 samples. but OMCTS was identified in only I sedin~nt

sample from the Rouge River, Detroit, and in2 sludgecake samples. EPA has reviewed this study, and, although locations below manufacturingp’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. ChemicalFate
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~adability

rate in a sediment/ water system.
B. Eniironmen tatEffects
Several acute toxicity tests were summarized in the proposedrule. EPA judged all the test data inadequate because they were basedon nominal test concentrations that exceeded the water solubility of OMCTS. Available bioconcentration data indicate that the bioconcentration factorforOMCTS 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 andinadequate to assess the toxicityof 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

I I Stal esme R~od

~, nsrlTNts
Sotut*tylest a~

fresh w~....

._ - - ....,.._ .~.. SOlubNitytest 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~R 797M00 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 Acutetoxicity, algae ........._.__~_... Acutetoiocity.

~

.. ..._....~..._ Acutetoxic~y,

r~’ibow trout

.. - ...._. ........ Acutebadly, silyei~id.

~ aflespafleed iy*w~....

.. ~.. .. ~ ActS.

~ mysatV_._.....__._.... Chronic toaaby,

~

.. Bioconcentration, tathead mira~.......

. .._..._,,... - .._....._..~.. T~I T.st*~ Fish early ble stagetest

- ~__.... Sedimenl/in’eertebraeeteat

- ...... ,.._._...... .. 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 ~olatilzatiorr rates 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~nts

in /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~hrud chronic 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. TierII testing includes a fish early life stage toxicity test and a test to determine sediment toxicity to benthic invertebrates. TierII tests will be performed only if any ofthe LC5O’s from the tier I tests are i~1

mg/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 tierI tests, tier II testing is nut required, EPA is not requiring that the manufacturers perform all the acute tests that were identified in the proposedrule. EPAbelieves that ifacute toxicity is observed, data on five species

are sufficient to assess the acute toxicity ofOMCTS to aquatic organisms. EPA is not including amysid chronic test in tier 11 because EPAbelieves that both the toxicity data from the daphnid life cycle test, and, iftriggered, the fish early life stage test and the sediment test with the midge, will be sufficientto assess the chronic toxicity ofOMCTS. EPA is not requiring areproduction test in mallardducks because available health effects data demonstrate that OMCTS is not toxic to mammals, and thus is not expected to be toxic to ducks. The ratoral LC5O is >2.0 g/kg and antifoam A (5 percent OMCTS) hadno adverse effects on rats in a 2-year feeding study (Ref. 17). The manufacturersagreed to perform the testing according to dtedEPA test standards and a specified test schedule. TierI testing will he completed in 16 months with interim statuareports due 6 and 12 months after the date of publication ofthis notice. Iftier 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 atextremely 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 ofOMCTS in water. The manufacturers will work on the development ofsuch methods and test s~.stemsduring the period after signature ofthe Consent Orderand 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 ofthis Testing Consent Order subjects any personwho exports
or intends to export OMCTS to the export notification requirements of section 12(b) ofTSCA. The specific requirements are listed in 40 CFR Part 707. In52 FR 23548ofJune 23. 1987, EPA issued 41) CFR 799.5000 as a listing of testing consent orders issued byEPA. This listing serves as notification to persons who export or who intend to exportchemical substances or mixtures which are thesubject oftesting consent orders that40 CFR Part 707 applies. VII. Rulemaking Record
EPA has established a record for this rule (docketnumber OPTS—42071B). This record contains the information EPA considered in developing this rule and the Consent Order andincludes the following informetion~
A. Supporting Documentation (I) Testing Consent Orderfor OMCTS. (2) Federal Registernotices pertaining to this rule andConsent Order consistingof: (a) Notice containing theITC designation of OMCTS to the Priority List (49 FR 46931; November 29. 1984). (b)Rules requiringTSCA section 8(a) and8(d) reporting on OMCTS (49 FR 46739 and 46741: November 28, 1984). (c) Notice ofEPA’s proposed test rule for octamethylcyclotetrasiloxane (50 FR 45123: October30, 1985). (d) Notice soliciting interested parties for developinga Testing ConsentOrder for OMCTS (53 FR11341: April 8, 1988). (3) Communicationsconsisting ot~ (a) Written letter. (b) Contact reports oftelephone 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 CorningCorporation. 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.” JournalofC’hemicalEngirocrtnc Data. 9(4):555—601. (October 1984). (6) Bruggemen, WA. eta). ‘~Absorptton arid retention ofpolydimethylsiloxanes (Silicone~)

in fish: preliminary experiments.” ToxicologyaridEnvironmental Chervistty. 7)41:287—296. (1984). (7) DowComing Corporation. Unpublished studyof T.H. Lane and Cl. Frye. Letter with attached studies fromCecil L Frye to Martha G. Price.Environmental ProtectionAgency. (December 12. 1984). (8) Kenaga. E.E.. “Predicted bioconcentration factors andaoild sorption coefficients ofpesticides andother chemicals.” Ecotoxicologyand EnvironmentalSafety, 4:26—38. (1980). (9) Interagency Testing Committee (ITC). Fifteenth Reportto the Administratorand Request for Comments. (November 29. 1984). (10) DowComing Corporation. Latterwith attachment from C.W. Lentz to MarthaPrice, Environmental Protection Agency. (February 27. 1986,. (11) DowCorning Corporation. Letter with attached studies from E.. Hobbsto M. Grief, InteragencyTesting Committee. (December 16.1982). (12) Browning. G.R. Silicone Products Diviaion. General Electric Co. Per~onat communication with M.G. Price, U.S. Environmental ProtectionAgency. (May 23. 1965). (13) Versar, Inc. Environmental risk assessment foroctamethaylcyclotetra

slloxane. 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 HealthCouncil on EPA’s proposed test rule for octamet.bylcyclotetrasiloxane. (February 28. 1986). (‘16)Dow Coming Corporation. A chronic reproductive limit teat of polyeth~(ene glycol sorbitan monolaurato andFederal 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~th F~id~y except legal holidays. VIII. OtherRegulatory Requirements The information collection requirements containedin this rule have been approved by the Office of Management and Budget (0MB) under the provisions ofthis Paperwork ReductionAct. 44 U.S.C. etseq. and
have been assigned 0MB control number 2070—0033. Public reporting burden forthis collection ofinformation 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 andre~iewing the collection of information. Send comments regarding the burden estimate or any other aspect ofthis 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: andto the Office ofInformation andRegulatory Affairs, Office of Management andBudget. 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 andreporting requirements.
Dated: December28, 1988.
Susan F. Vogt, Acting .tssistant .4dministrntor,~or Pi’~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 orderto the tahle to read as follows: § 799.5000 TestIng consent orders.

CA.S No.

-~ S~tmianc. ornsxti,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) ~ui~ co~~w