On October 27, 2017, the California Office of Environmental Health Hazard Assessment (OEHHA) added N,N‑dimethylformamide, 2‑mercaptobenzothiazole, and tetrabromobisphenol A (TBBPA) to the list of chemicals known to the State of California to cause cancer for purposes of the Safe Drinking Water and Toxic Enforcement Act of 1986 (Proposition 65).
Under Prop 65, companies are required to warn consumers of potential exposure to substances which cause cancer or reproductive harm. TBBPA is widely used as a flame retardant in printed circuit boards (PCBs). In PCBs TBBPA is used reactively, which means it is reacted into the resins and is not chemically available.
The basis for the listing of N,N‑dimethylformamide, 2‑mercaptobenzothiazole, and tetrabromobisphenol A was described in a public notice published in the June 30, 2017, issue of the California Regulatory Notice Register (Register 2017, No. 26-Z).