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 December 08, 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

February 25, 2011: Availability of Hazard Identification Materials for Sulfur Dioxide and Announcement of the May 12 and 13, 2011 Developmental and Reproductive Toxicant Identification Committee Meeting

The hazard identification document entitled: “Evidence on the Developmental and Reproductive Toxicity of Sulfur Dioxide" is available for public comment. The DART IC meeting is scheduled for May 12 and 13, 2011.

February 25, 2011: Release of Draft Interpretive Guideline No. 2011-001 Hand-To-Mouth Transfer of Lead Through Exposure to Consumer Products

Release of the draft Interpretive Guideline No. 2011-001: Hand-to-mouth transfer of lead through exposure to consumer products.

February 21, 2011: Extension of Comment Period - Proposed Rulemaking, Title 27, California Code of Regulations, Amendment to Section 25705 - Specific Regulatory Levels Posing No Significant Risk: 4-Methylimidazole (4-MEI)

Extension of comment period for the proposal to establish a specific regulatory level posing no significant risk for 4-methylimidazole by amending Title 27, California Code of Regulations, section 25705.

February 11, 2011: Request for Information on the Carcinogenic Hazards of: Clomiphene and its salts, 2,6-Dimethyl-N-nitrosomorpholine, Haloperidol, Tris(1,3-dichloro-2-propyl) phosphate (TDCPP)

Announcement of chemicals selected in 2011 by OEHHA for consideration for listing by the Carcinogen Identification Committee and request for relevant information on the carcinogenic hazards of these chemicals: clomiphene and its salts, 2,6-dimethyl-N-nitrosomorpholine, haloperidol, tris(1,3-dichloro-2-propyl) phosphate (TDCPP).

February 11, 2011: Comment Period - Request for Information on the Carcinogenic Hazards of: Clomiphene and its salts, 2,6-Dimethyl-N-nitrosomorpholine, Haloperidol, Tris(1,3-dichloro-2-propyl) phosphate (TDCPP)

2011 public comment period on the Carcinogenic Hazards of: Clomiphene and its salts, 2,6-Dimethyl-N-nitrosomorpholine, Haloperidol, Tris(1,3-dichloro-2-propyl) phosphate (TDCPP)