Availability of Hazard Identification Materials for Vinclozolin, a Chemical Listed Under the Authoritative Body Mechanism and Under Review for Possible Delisting by the OEHHA Science Advisory Board’s Carcinogen Identification Committee

Sep 8, 2006

The California Environmental Protection Agency’s (Cal/EPA) Office of Environmental Health Hazard Assessment (OEHHA), as lead agency for the implementation of the Safe Drinking Water and Toxic Enforcement Act of 1986 (Proposition 65, California Health and Safety Code 25249.5 et seq.) maintains the Proposition 65 list of chemicals that have been identified by the State to cause cancer, birth defects or other reproductive harm. One of the mechanisms by which a chemical can be put on the Proposition 65 list is when the chemical has been identified as causing cancer by an organization that has been designated as “authoritative” for purposes of Proposition 65. The authoritative bodies for identifying agents as causing cancer are: U.S. Environmental Protection Agency (U.S. EPA), U.S. Food and Drug Administration, National Institute of Occupational Safety and Health, National Toxicology Program, and the International Agency for Research on Cancer.

If the lead agency finds that a chemical is no longer identified by the authoritative body as causing cancer or reproductive toxicity, the listing under the Proposition can be reconsidered (Title 22, Cal. Code Regs. §12306(j)). Chemicals listed “as causing cancer” which are under reconsideration and which have been placed on the list by the authoritative bodies mechanism are referred to the Carcinogen Identification Committee (CIC), the state’s qualified experts for carcinogenicity determinations under the Proposition (Title 22, Cal. Code Regs. §12306(j)). The CIC then makes a recommendation regarding whether the chemical has been "clearly shown, through scientifically valid testing according to generally accepted principles to cause cancer” (Title 22, Cal. Code Regs. §12305 (a)(1)).

Vinclozolin (CAS No. 50471-44-8) was listed “as causing cancer” under Proposition 65 on August 20, 1999, based upon its 1996 classification as a probable human carcinogen (Group B2) by the U.S. EPA. The evaluation and conclusions are reported in U.S. EPA’s Memorandum on the Carcinogenicity Peer Review of Vinclozolin (2nd). In 2000, the U.S. EPA finalized a re-evaluation in a Cancer Assessment Document, Evaluation of the Carcinogenic Potential of Vinclozolin (Fourth Review), changing its classification to Group C, possible human carcinogen.

The CIC will consider the U.S. EPA’s reclassification and the carcinogenicity evidence for vinclozolin at a public meeting scheduled for November 16, 2006. It is expected that the CIC will make a recommendation at this meeting regarding whether vinclozolin should continue to be included on the Proposition 65 list.

Hazard identification materials, including U.S. EPA review documents and carcinogenicity evidence for vinclozolin, have been compiled to provide the CIC with relevant information for use in its deliberations. Copies of these materials are available in the downloads section below. Documents are being posted in the form they were provided to OEHHA. If you are unable to access or read these documents, please contact the Proposition 65 Office with the Proposition 65 Implementation office at P65Public.Comments@oehha.ca.gov or (916) 445-6900 to request a copy in an alternative format. OEHHA will provide documents in alternative formats when possible.

Written public comments related to the reconsideration of the listing of vinclozolin on the Proposition 65 list of chemicals known to the State to cause cancer should be submitted by October 30, 2006 to:

Cynthia Oshita
Office of Environmental Health Hazard Assessment,
Street Address: 1001 I Street
Sacramento, CA 95814

Mailing Address: P.O. Box 4010
Sacramento, California 95812-4010

Fax No.: (916) 323-8803
Telephone: (916) 445-6900
Via E-mail: coshita@oehha.ca.gov