California: Vinyl Acetate Listed under Proposition 65

The Office of Environmental Health Hazard Assessment (OEHHA) has issued guidance regarding Vinyl Acetate (CAS #: 108-05-4). The Carcinogen Identification Committee (CIC) added Vinyl Acetate to California’s Proposition 65 list of carcinogens on January 3, 2025.

As of January 3, 2026, businesses must comply with Proposition 65 warning requirements for consumer products containing Vinyl Acetate. OEHHA’s information letter provides guidance on evaluating exposures and determining when warnings are needed. Manufacturers, importers, and distributors should review their products and update labelling to ensure compliance.

Key Points for Businesses:

• Vinyl acetate is primarily used as a monomer in the production of polymers and copolymers such as polyvinyl acetate (PVA), polyvinyl alcohol, polyvinyl acetals, ethylene-vinyl acetate (EVA) copolymers, polyvinyl chloride-acetate copolymers, and vinyl acetate-vinyl laurate copolymers.

• Only the monomer is listed; the polymers and copolymers themselves are not listed, though residual unreacted vinyl acetate may be present.

• Evaluating exposure: Tests should reflect the amount of vinyl acetate released during normal use, storage, or maintenance. Testing that artificially dissolves the polymer to measure vinyl acetate is not appropriate.

• Legal considerations: Before filing a Proposition 65 lawsuit, private parties must issue a 60-day Notice and provide a Certificate of Merit with sufficient factual information to establish potential exposure (Health & Safety Code §25249.7(d)(1)). The mere presence of vinyl acetate-based polymers in a product is not sufficient to demonstrate exposure.