DEPARTMENT OF LABOR

Occupational Safety and Health Administration

29 CFR Parts 1910, 1915 and 1926

[Docket No. H-071B]

Occupational Exposure to Methylene Chloride

AGENCY: Occupational Safety and Health Administration (OSHA), Department of Labor.

ACTION: Proposed rule; Limited reopening of the rulemaking record.

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SUMMARY: On October 24, 1995, the Occupational Safety and Health Administration (OSHA) reopened the record (60 FR 54462) for the proposed revision of the regulation of methylene chloride (MC) (56 FR 57036, November 7, 1991) to incorporate recently concluded research on MC carcinogenicity.

The studies incorporated in the October 24 notice address the mechanism by which MC metabolites induce lung and liver cancer in mice and draw conclusions regarding the relevance of the mouse data to the assessment of human cancer risk. OSHA determined that those studies are relevant to full consideration of concerns raised by the MC rulemaking and reopened the record until November 24, 1995, to allow the public an opportunity to comment.

The October 24 notice generated substantially more interest than OSHA anticipated and the Agency is concerned that the initial 30 days was insufficient to allow full participation by interested parties. Accordingly, OSHA is reopening the comment period until December 29, 1995.

DATES: Written comments on the materials incorporated through the October 24, 1995 notice of reopening must be postmarked by December 29, 1995.

ADDRESSES: Comments are to be submitted in quadruplicate to the Docket Office, Docket No. H-071B, U.S. Department of Labor, room N-2634, 200 Constitution Avenue, NW., Washington, DC 20210. Telephone (202) 219- 7894. Written comments limited to 10 pages or less in length also may be transmitted by facsimile to (202) 219-5046, provided that the original and 3 copies are sent to the Docket Office thereafter.

FOR FURTHER INFORMATION CONTACT: Anne C. Cyr, Office of Information and Consumer Affairs, Occupational Safety and Health Administration, U.S. Department of Labor, room N-3647, 200 Constitution Avenue, NW., Washington, DC 20210. Telephone (202) 219-8148. For electronic copies of this Federal Register notice, contact the Labor News Bulletin Board (202) 219-4784; or OSHA's WebPage on Internet at http://www.osha.gov/. For news releases, fact sheets, and other short documents, contact OSHA FAX at (900) 555-3400 at $1.50 per minute.

SUPPLEMENTARY INFORMATION:

I. Background

On November 7, 1991, OSHA issued a notice of proposed rulemaking (56 FR 57036) to address the significant risks of MC-induced health effects. The proposed rule required employers to reduce occupational exposure to MC and to institute ancillary measures, such as employee training and medical surveillance, for further protection of MC-exposed workers.

OSHA convened public hearings (57 FR 24438, June 9, 1992) in Washington, DC on September 16-24, 1992 and in San Francisco, CA on October 14-16, 1992. The post-hearing period for the submission of additional briefs, arguments and summations ended on March 15, 1993.

On March 11, 1994, OSHA reopened the rulemaking record for 45 days (59 FR 11567) to obtain public input on three documents incorporated into the rulemaking record, one of which examined the relationship between MC exposure and human carcinogenesis. The limited reopening, which ended on April 25, 1994, generated 37 comments.

The Halogenated Solvents Industry Alliance (HSIA) subsequently submitted several recently completed studies which address the mechanism for MC-induced cancer in mice and which assert that species differences in the metabolism of MC preclude the use of mouse data to characterize human cancer risk. The utility of the mouse data in assessing human risk is a critical issue in this rulemaking. Therefore, OSHA concluded that it was appropriate, even at this late stage of the rulemaking process, to consider the HSIA-submitted studies in the drafting of the final rule. Accordingly, on October 24, 1995, the Agency reopened the rulemaking record to incorporate those studies and to provide the public with an opportunity to comment.

OSHA has been considering the impact of species differences on the MC risk assessment throughout this rulemaking, and has generated an extensive record over the nearly four years since the proposal was published. While the Agency has agreed with the HSIA that the new materials should be taken into account, the Agency still believes that every effort should be made to conclude this rulemaking expeditiously. To that end, OSHA reopened the record for 30 days to receive any additional comments and information regarding this issue. While the record was open, OSHA received many requests for the studies. Due to the substantial interest generated by the October 24 notice, the Agency has decided to allow interested parties additional time in which to submit their comments. Therefore, OSHA is extending the comment period until December 29, 1995.

OSHA will provide interested parties with copies of the materials incorporated into the methylene chloride record through the October 24, 1995 reopening notice, upon request, to facilitate full and timely public participation. Requests for copies of the studies should be addressed to the Christine Whittaker, Room N-3718, Health Standards Programs, OSHA, U.S. Department of Labor,200 Constitution Avenue, NW., Washington, DC 20210. Telephone: (202) 219-7174. Fax: (202) 219-7125.

II. Public Participation

Comments

Written comments regarding the materials incorporated into the methylene chloride record through the October 24, 1995 reopening notice must be postmarked by December 29, 1995. Four copies of these comments must be submitted to the Docket Office, Docket No. H-071B, U.S. Department of Labor, room N-2625, 200 Constitution Avenue, NW., Washington, DC 20210. (202) 219-7894. All materials submitted will be available for inspection and copying at the above address. Materials previously submitted to the Docket for this rulemaking need not be resubmitted.

III. Authority

This document was prepared under the direction of Joseph A. Dear, Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, 200 Constitution Avenue, NW., Washington, DC 20210.

It is issued under section 6(b) of the Occupational Safety and Health Act (29 U.S.C. 655), and 29 CFR part 1911.

Signed at Washington, DC, this 1st day of December 1995.

Joseph A. Dear,
Assistant Secretary of Labor.

[FR Doc. 95-29719 Filed 12-5-95; 8:45 am]

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