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N-Methyl-N-Formylhydrazine added to Prop 65 as carcinogen
California Proposition 65 (Safe Drinking Water and Toxic Enforcement Act of 1986)California Office of Environmental Health Hazard Assessment (OEHHA)California
Announced
Dec 8, 2025
Effective
Dec 8, 2025
Implementation
Dec 8, 2026
Description
OEHHA added N-methyl-N-formylhydrazine to the Proposition 65 list as a carcinogen effective December 8, 2025. The listing was done via the 'State's Qualified Experts' mechanism based on the Carcinogen Identification Committee's determination that this chemical was clearly shown to cause cancer. Businesses have a one-year grace period until December 8, 2026 to provide warnings for significant exposures.
Sources
- OfficialProposition 65
Key Findings
N-Methyl-N-Formylhydrazine added to Prop 65 as carcinogen
Effective December 8, 2025, the Office of Environmental Health Hazard Assessment added N-methyl-N-formylhydrazine 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 determination that this chemical was clearly shown to cause cancer. October 21, 2025:Request for Relevant Information on the Reproductive Toxi