Availability of the Draft Hazard Identification Documents for Methyl Tertiary-Butyl Ether (MTBE)

The California Environmental Protection Agency’s Office of Environmental Health Hazard Assessment (OEHHA) is the lead agency for the implementation of the Safe Drinking Water and Toxic Enforcement Act of 1986 (Proposition 65).

The Carcinogen Identification Committee (CIC) and the Developmental and Reproductive Toxicant (DART) Identification Committee of OEHHA’s Science Advisory Board advise and assist OEHHA in compiling the list of chemicals known to the State to cause cancer or reproductive toxicity, which is mandated by Health and Safety Code Section 25249.8. The Committees serve as the State’s qualified experts for rendering an opinion as to whether a chemical has been clearly shown, through scientifically valid testing according to generally accepted principles, to cause cancer or reproductive toxicity.

The Local Drinking Water Protection Act of 1997 [Assembly Bill 592 (Kuehl) and Senate Bill 1189 (Hayden)] requires the State’s qualified experts for Proposition 65 (the CIC and DART Identification Committee) to make a finding on or before January 1, 1999 as to whether methyl tertiary-butyl ether (MTBE) has been clearly shown to cause cancer or reproductive toxicity. In a December 5, 1997 public notice published in the California Regulatory Notice Register, OEHHA requested information in relation to the preparation of draft hazard identification documents on MTBE to support the committee members in their deliberations. The 60-day data call-in ended on February 2, 1998. Information and data were received and considered in the preparation of the draft hazard identification documents.

OEHHA has prepared the draft hazard identification documents entitled, "Evidence on the Carcinogenicity of Methyl Tertiary-Butyl Ether (MTBE)" and "Evidence on the Developmental and Reproductive Toxicity of Methyl Tertiary-Butyl Ether (MTBE)". This notice marks the beginning of a 60-day public comment period on these documents. Copies of the draft documents are available from the Proposition 65 Implementation Office and may be requested by calling (916) 445-6900.

Comments should be submitted in triplicate and directed to:

the Proposition 65 Office
Office of Environmental Health Hazard Assessment
Post Office Box 4010
Sacramento, CA 95812-4010
FAX (916) 327-1097

In order to be considered, comments must be received at OEHHA by 5:00 p.m. on Tuesday, November 17, 1998.

OEHHA will organize and index the comments received and forward the information to the respective committee members two weeks prior to the meetings at which the evidence will be considered. Dates and locations of the next meetings of the CIC and DART Identification Committee will be announced in a future public notice.