[Federal Register Volume 59, Number 218 (Monday, November 14, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-28019]


[[Page Unknown]]

[Federal Register: November 14, 1994]


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ENVIRONMENTAL PROTECTION AGENCY
[OPPTS-42116B; FRL-4910-3]

 

Testing Consent Order For 4-Vinylcyclohexene; Proposed Deletion 
of Triggered In vivo Alkaline Elution Assay

AGENCY: Environmental Protection Agency (EPA).

ACTION: Request for comment.

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SUMMARY: This notice invites public comment on the proposed deletion of 
the triggered in vivo alkaline elution assay on 4-vinylcyclohexene (4-
VCH) currently required by the enforceable consent agreement 
incorporated in the testing consent order for 4-VCH (Docket No. OPPTS-
42116B).
DATES: Written comments must be received on or before December 14, 
1994.
ADDRESSES: Submit written comments, identified by the document control 
number (OPPTS-42116B) in triplicate to: TSCA Nonconfidential 
Information Center (NCIC) (7407), Office of Pollution Prevention and 
Toxics, Environmental Protection Agency, Northeast Mall (NEM) Rm. B-
607, 401 M St., SW., Washington, DC 20460. A public version of the 
administrative record supporting this action, without confidential 
business information (CBI) is available for inspection at the above 
address in the NEM, Rm. B-607, from 12:00 noon to 4:00 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's procedures for requiring the testing 
of chemical substances under section 4 of the Toxic Substances Control 
Act (TSCA) include the use of enforceable consent agreements (ECAs). 
The manufacturers of 4-VCH agreed to a testing program which included 
an in vivo alkaline elution assay, if triggered by a negative or 
equivocal 13-week micronucleus test in both the rat and mouse, (56 FR 
47912, September 23, 1991). In a letter dated August 10, 1994, the 
Chemical Manufacturers Association (CMA) requested, on behalf of the 
nine companies subject to the testing consent order (E.I. Du Pont de 
Nemours & Company, Exxon Chemical Co., Lyondell Petrochemical Co., Oxy 
Petrochemicals, Inc., Shell Oil Co., Texaco Chemical Co., Texas 
Petrochemicals Corp., Dow Chemical USA., and Union Carbide Chemicals 
and Plastics Co., Inc.), that the requirement to perform an in vivo 
alkaline elution assay study on 4-VCH be deleted because this 
requirement is not scientifically justifiable at this time.
    The ECA for 4-VCH requires a 2-day micronucleus test in mice and 
rats. If this test is negative or equivocal, the ECA requires a 90-day 
micronucleus test. If the results of the 90-day micronucleus test are 
negative or equivocal, a testicular alkaline elution assay is required. 
Results of both the 2-day and 90-day micronucleus tests have been 
submitted to EPA and EPA believes that the results of both tests 
support the conclusion that 4-VCH does not induce increased frequencies 
of micronucleated erythrocytes in the bone marrow of mice or rats.
    The literature indicates that 4-VCH is not mutagenic in the 
Salmonella/Ames assay and that 4-VCH induces negative responses in in 
vitro cytogenetic assays (sister chromatid exchange and chromosome 
aberration). Although 4-VCH was reported to induce gene mutations in 
L5178Y mouse lymphoma cells, further evaluation of the data by both the 
National Toxicology Program and the EPA indicate that the evidence for 
activity in this assay is equivocal, at most. Results of subchronic and 
reproductive studies indicate that 4-VCH does not cause significant 
testicular effects in male mice or rats. The majority of the scientific 
evidence suggests that 4-VCH is nongenotoxic in vitro and in vivo and 
does not pose a risk of potential heritable effects to male germ cells.
    CMA claims, and EPA preliminarily agrees, that there is no 
scientific justification to conduct the alkaline elution test at this 
time. Under 40 CFR 790.68(b)(2)(iii), EPA may approve modifications to 
test standards that significantly affect the scopt of the ECAs but only 
after providing the public with notice and an opportunity for comment 
on such modifications. Furthermore, under Sec. 790.68(a), if public 
comments indicate that no consensus exists on making the change, the 
issue must be negotiated before any such adjustment can become 
effective. Therefore, interested persons have 30 days from publication 
of this notice to provide written comments on the elimination of the in 
vivo alkaline elution assay study from the ECA for 4-VCH. If comments 
indicate that differences of opinion exist regarding this change, EPA 
will conduct negotiations following the procedures specified in 40 CFR 
790.22(b). If the 30 day deadline passes and no adverse public comments 
have been received, EPA will grant the proposed modification without 
further notice.
    Authority: 15 U.S.C. 2603

    Dated: October 31, 1994.

Lynn R. Goldman
Assistant Administrator for Prevention, Pesticides and Toxic 
Substances.

[FR Doc. 94-28019 Filed 11-10-94; 8:45 am]
BILLING CODE 6560-50-F