Vinyl Acetate added to the Proposition 65 List for Cancer

Vinyl Acetate Listed as a Carcinogen

Effective January 3, 2025, the Office of Environmental Health Hazard Assessment (OEHHA) has added vinyl acetate to the Proposition 65 list as a carcinogen. This listing was done via the “State’s Qualified Experts” mechanism, based on the Carcinogen Identification Committee’s (CIC) determination that this chemical was clearly shown to cause cancer. 

The warning requirement for significant exposures to vinyl acetate will take effect on January 3, 2026.

Summary of CIC Meeting

A meeting of the CIC was held on December 19, 2024, starting at 10:00 am. During the meeting, OEHHA staff presented a summary of evidence on the carcinogenicity of vinyl acetate. This was followed by a discussion and deliberation on the evidence by the CIC, and by public comment. The CIC then determined that vinyl acetate was clearly shown, through scientifically valid testing according to generally accepted principles, to cause cancer by a vote of 11 (yes) to 0 (no).

Ahead of the meeting, OEHHA had issued a request for relevant information on the potential carcinogenicity of vinyl acetate, which opened on July 7, 2023 and closed on September 18, 2023. The data call-in was followed by publication of the hazard identification document entitled “Evidence on the Carcinogenicity of Vinyl Acetate” and a public comment period from October 4, 2024 to November 18, 2024. 

At the meeting, the CIC also voted 11 — 0 in favor of the consent item to add 2,2,3-trifluoro-3-(trifluoromethyl)oxirane (also known as hexafluoropropylene oxide, or HFPO) to the list of chemicals for which testing is required but has been inadequate (California Code of Regulations (CCR) Title 27 Section 27000). As described in the OEHHA staff report, data requirements for HFPO are still required. This list of chemicals is distinct from the Proposition 65 list.

Finally, OEHHA staff presented updates on chemical listing via the administrative listing mechanisms, safe harbor levels, and other regulations and litigation since the last CIC meeting.

OEHHA was pleased to swear in two new members of the CIC; Dr. Ludmil Alexandrov, Associate Professor in the departments of Bioengineering and Cellular and Molecular Medicine at the University of California San Diego; and Dr. Dean Felsher, Professor of Medicine and Pathology at Stanford University School of Medicine. Both were appointed to the CIC by the Governor in 2024. 

Meeting Agenda

  • Welcome and Opening Remarks
  • Swearing in of New CIC Members
  • Consideration of Listing Vinyl Acetate for Carcinogenicity under Proposition 65:
    • Staff presentation
    • Committee discussion
    • Public comments
    • Committee discussion and decision
  • Consent Item - Update of the California Code of Regulations Title 27 Section 27000 List of Chemicals Which Have Not Been Adequately Tested as Required
  • Staff Updates
    • Chemical listings via the administrative listing mechanisms
    • Safe harbor levels
    • Other regulations and litigation
  • Summary of Committee Actions

Data Call-In

On July 7, 2023 OEHHA started a data call-in process to solicit information on vinyl acetate from the public. 

Link to Public Comments

Downloads

Chemical Reference