Proposition 65

Proposition 65, officially known as the Safe Drinking Water and Toxic Enforcement Act of 1986, was enacted as a ballot initiative in November 1986. The proposition protects the state's drinking water sources from being contaminated with chemicals known to cause cancer, birth defects or other reproductive harm, and requires businesses to inform Californians about exposures to such chemicals.

Proposition 65 requires the state to maintain and update a list of chemicals known to the state to cause cancer or reproductive toxicity.


Questions about Proposition 65? Check our Frequently asked Questions page or contact the Proposition 65 office: (916) 445-6900 or email

Reports, Notices, Documents

May 1, 1990: Final Statement of Reasons - Quantitative Risk Assessment
This regulatory action amends subsection (b) of section 12703 to add two additional examples of public health considerations: (1) Where chemicals in food are produced by cooking necessary to render the food palatable or to avoid microbiological contamination; and (2) where chlorine disinfection in compliance with all applicable state and federal safety standards is necessary to comply with sanitation requirements. 
Mar 1, 1990: Final Statement of Reasons - Formally Required to be Labeled or Identified As Causing Cancer or Reproductive Toxicity
This final statement of reasons sets forth the reasons for the final language adopted by the Agency for section 12902 and responds to the objections and recommendations submitted regarding that section. This regulation provides uniform definitions and establishes a process by which the lead agency can evaluate chemicals for listing pursuant to this provision of the Act. 
Feb 1, 1990: Final Statement of Reasons - Chemicals Formally Identified by Authoritative Bodies
The purpose of this regulation is to implement and make specific the provision of Health and Safety Code section 25249.8 which provides that a chemical is known to the state to cause cancer or reproductive toxicity "if a body considered to be authoritative by [the Panel] has formally identified it as causing cancer or reproductive toxicity."