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

Pentosan polysulfate sodium, pioglitazone, triamterene and pulegone listed effective April 18, 2014 as known to the state of California to cause cancer via the Labor Code.

Effective April 4, 2014, OEHHA is removing n-butyl glycidyl ether, diglyciyl ether, phenyl glycidyl ether, methyl isopropyl ketone and α-methyl styrene from the list of chemicals known to the State to cause reproductive toxicity.

Chemicals listed effective March 28, 2014: Methyl isobutyl ketone (MIBK), known to the state of California to cause reproductive toxicity, via the authoritative bodies mechanism; and Megestrol acetate, known to the state of California to cause cancer, via the formally required to be labeled or identified mechanism.

A public meeting of the DART IC will be held on Wednesday, March 19, 2014.

A meeting of the Proposition 651 Developmental and Reproductive Toxicant Identification Committee (DARTIC) was held on March 19, 2014.