If you sell products into California, chances are you have already heard about the state law known as Proposition 65 (Prop. 65), which gives consumers and their attorneys the ability to sue businesses that do not include warning labels on products containing certain chemicals. Prop. 65 was approved by voters in 1986 to enable Californians to be aware of the presence of chemicals known to cause cancer, birth defects or other reproductive harm. To achieve this goal, Prop. 65 allows consumers to sue companies that sell products in California that expose consumers to certain chemicals without carrying an acceptable warning.
https://www.sema.org/sema-news/2016/12/california-finalizes-new-proposition-65-warning-rules