As 2025 came to a close, the Proposition 65 (Prop 65) landscape in California continued to evolve rapidly, reflecting shifting enforcement patterns, major litigation outcomes, and significant regulatory developments. This year-end review highlights some of the important Prop 65 developments from 2025 and what they may mean for businesses moving into 2026. Top Charts- Most “Streamed” Categories and Chemicals:
Prop 65 permits private actors to bring enforcement actions “in the public interest,” provided the private enforcers first issue a 60-day notice of intent to sue the alleged violator.[1]
In 2025, the top targeted product categories included:[2]
- Food and Herbal Supplements
- Thermal Receipt Paper and Stickers/Labels
- Beauty/Personal Care/Hygiene/Cosmetics/Sanitizers
Top targeted chemicals included:
- Metals (including lead, cadmium, mercury and arsenic)
- Bisphenol S (BPS) & Bisphenol A (BPA)
- Phthalates (chemicals used in plastic)
A Case That Changed The Tune- Acrylamide Warnings Are Unconstitutional:
One of the most notable Prop 65 opinions in 2025, California Chamber of Commerce v. Bonta, No. 2:19-cv-02019-DJC-JDP, was issued by a Federal District Court in the Eastern District of California.
Acrylamide is a substance that forms through a natural chemical reaction in certain plant-based foods during high-temperature cooking and can be found in foods like potato chips, bread, grilled vegetables, nuts, crackers, and olives. The California Chamber of Commerce (“Cal Chamber”) sued five years ago challenging the statewide requirement under Proposition 65 for warning labels on foods containing acrylamide. The Court ruled that Prop 65 warning requirements for dietary acrylamide are unconstitutional. It granted summary judgement in favor of Cal Chamber, holding that the Prop 65 warning requirement for dietary acrylamide is controversial due to the lack of scientific consensus and unnecessarily burdens businesses by compelling them to convey disputed scientific information. As a result, the District Court issued a permanent injunction enjoining both the California Attorney General and all private enforcers from enforcing the acrylamide warning requirements.
The California Attorney General filed a notice of appeal on June 2, 2025. Mediation is currently scheduled for February 3, 2026. A full write up of the California Chamber of Commerce v. Bonta decision can be found here.[3] The ruling is available here.[4]
What’s Trending?- BPS Notices Surge in 2025:
BPS notices were also on the rise in 2025. BPS accounted for approximately 14% of the targeted chemicals in the second quarter of 2025, rising to 34% in the third quarter.[5]
In response, California’s Office of Environmental Health Hazard Assessment (OEHHA) issued an informational letter to clarify how the Prop 65 regulations apply to thermal paper items containing BPS.
The letter advises that consumer product warning regulations and safe harbor warnings apply to items that accompany consumer goods at the time of purchase, such as receipts, labels, tags, product stickers, shipping materials, packaging, and instructions/manuals, in addition to the product itself. These requirements apply to both in-person and online transactions.
Where thermal paper containing BPS is used, OEHHA advises that a warning must be provided before an exposure occurs, explaining that a warning printed on the receipt itself does not satisfy the safe harbor warning regulations. OEHHA suggests alternative approaches, such as posting warning signs at or near cash registers, and recommends considering BPS-free alternatives, including electronic receipts and phenol-free paper and labels. The full letter is available here.[6]
New Addition To The Playlist- OEHHA Issues Informational Letter Regarding Testing for Vinyl Acetate:
As reported in May of 2025, OEHHA added vinyl acetate—but not polymers and copolymers made from vinyl acetate such as polyvinyl acetate (PVA), polyvinyl alcohol, polyvinyl acetals, ethylene-vinyl acetate (EVA) copolymers, polyvinyl chloride-acetate copolymers, and vinyl acetate-vinyl laurate copolymers—to the Prop 65 chemical list as a carcinogen. The warning requirement for exposure to vinyl acetate took effect on January 3, 2026.[7]
Because of the listing of vinyl acetate but not its polymers and copolymers, on December 23, 2025, OEHHA issued an additional informational letter explaining the limitation on the Prop 65 listing and addressing testing considerations for vinyl acetate. In that letter, OEHHA advised that when a party issues a 60-day Notice, the party must provide the Attorney General with factual information in a Certificate of Merit sufficient to establish the basis of Notice, clarifying that “[t]he fact that a consumer product contains a vinyl acetate-based polymer or copolymer is not, by itself, factual information sufficient to establish a potential exposure to vinyl acetate”. The full letter is available here.[8]
What’s Next On the Queue?- Looking Ahead and How We Can Help:
In 2026 businesses will need to remain attentive to developments under Prop 65 to effectively manage compliance and litigation risk. Whether you need a review of your Prop 65 protocols, support with notices of violation, or representation in Prop 65 litigation, our experienced attorneys are ready to help your business successfully manage and navigate California’s evolving Prop 65 requirements.
FOOTNOTES
[1] Cal. Health & Safety Code § 25249.7(d)(1)
[2] CA Proposition 65:60 Day Notice Summary for Q3 2025 | Bureau Veritas CPS
CA Proposition 65:60 Day Notice Summary for Q2 2025 | Bureau Veritas CPS
CA Proposition 65: 60 Day Notice Summary for Q1 2025 | Bureau Veritas CPS
[4] https-ecf-caed-uscourts-gov-doc1-033115108581.pdf
[5] CA Proposition 65:60 Day Notice Summary for Q3 2025 | Bureau Veritas CPS
CA Proposition 65:60 Day Notice Summary for Q2 2025 | Bureau Veritas CPS