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 law 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 the list of chemicals subject to the law’s requirements.

Questions about Proposition 65?  Visit our Proposition 65 Warnings website.

Proposition 65 Resources

About Proposition 65

The Safe Drinking Water and Toxic Enforcement Act

The Proposition 65 List

The current Proposition 65 list is dated January 03, 2025

Meetings, Hearings and Workshops

Upcoming and past meetings, hearings and workshops

Notices

All Proposition 65 Notices

Laws and Regulations

Links and downloads related to Proposition 65 statute and regulations

Warnings

Visit this website to learn about warnings for exposures to chemicals on the Proposition 65 List

How chemicals are added to the Proposition 65 list

Learn how chemicals are added to the list

Safe Use Determinations

A Safe Use Determination (SUD) is a written statement issued by OEHHA, interpreting and applying Proposition 65 regulations to specific facts in response to a request by a business or trade group

Interpretive Guidelines for Proposition 65

An Interpretive Guideline interprets Proposition 65 regulations as applied to specific facts

Information Letters

Letters about Proposition 65's application from OEHHA to interested parties

Warning Regulations

Clear and reasonable warnings

Searchable Proposition 65 Chemical Database

Search the Proposition 65 Chemical Database

Safe harbor levels

Proposition 65 No Significant Risk Levels (NSRLs) and Maximum Allowable Dose Levels (MADLs)

Reports, Notices, Documents

OEHHA is removing chloramphenicol from the list of chemicals known to the state to cause cancer, for purposes of Proposition 65.  The delisting of chloramphenicol is effective January 4, 2013. 

OEHHA is removing dienestrol [CAS No. 84-17-3] from the list of chemicals known to the state to cause cancer, for purposes of Proposition 651.  The delisting of dienestrol is effective JANUARY 4, 2013. 

Intent to change basis of listing for Actinomycin D from the Labor Code to listing via the formally required to be labeled or identified mechanism.

Per court ruling, the Office of Environmental Health Hazard Assessment (OEHHA) may not list a chemical as causing cancer under Proposition 65 pursuant to the Labor Code mechanism set out in Health and Safety Code section 25249.8(a), referencing Labor Code section 6382(d), solely on the basis of its identification by the International Agency for Research on Cancer (IARC) as being possibly carcinogenic to humans (Group 2B), where that determination is based on less than sufficient evidence of carcinogenicity in humans and animals. The language in the court’s ruling applies to ten chemicals.

Notice of intent to list Styrene as a carcinogen by the Labor Code mechanism