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

September 19, 2019: Withdrawal of Notice of Proposed Proposition 65 Rulemaking, Title 27, Cal Code of Regs, Section 25821 (a) and (c)

On October 5, 2018, the Office of Environmental Health Hazard Assessment (OEHHA) issued a notice of proposed rulemaking to adopt amendments to Title 27, California Code of Regulations, section 25821. The amendments were intended to clarify when and how a person could average concentrations of a listed chemical in a food, and identified the use of the arithmetic mean as the default method of calculation of individual exposure.

September 13, 2019: Chemicals Listed Effective September 13, 2019 as Known to The State of California to Cause Cancer: 2-Amino-4-Chlorophenol; 2-Chloronitrobenzene; 1,4-Dichloro-2-Nitrobenzene; 2,4-Dichloro-1-Nitrobenzene; N,N-Dimethylacetamide, and Para-Nitroanisole

The chemicals are being added to the list of chemicals known to the State of California to cause cancer for purposes of Proposition 65. The listing of these chemicals is pursuant to the “Labor Code” listing mechanism.

August 12, 2019: OEHHA Statement Regarding US EPA’s Press Release and Registrant Letter on Glyphosate

OEHHA added glyphosate to the Proposition 65 list of carcinogens in July 2017, based on a finding by the World Health Organization’s International Agency for Research on Cancer (IARC) that glyphosate is both an animal carcinogen and “probably carcinogenic to humans”.

July 16, 2019: Notice of Amendments to Article 6 Clear and Reasonable Warnings Rental Vehicle Exposure Warnings

This rulemaking adds Sections 25607.36 and 25607.37 to Article 6 as safe harbor tailored warnings for exposures to listed chemicals that may occur through the rental of a motor vehicle.

July 12, 2019: Notice of Extension of Comment Period for Modification to Text of Proposed Regulation: Proposed Amendment to Sections 25821(a) and (c) Level of Exposure to Chemicals Causing Reproductive Toxicity: Calculating Intake by the Average Consumer of a Product

OEHHA is requesting comments on the modifications to the regulatory text. In order to be considered, OEHHA must receive comments by August 5, 2019, which is the designated close of the comment period. All comments will be posted on the OEHHA website at the close of the public comment period.