California Proposition 65
The Safe Drinking Water and Toxic Enforcement Act of 1986, also referred to as Proposition 65, is a California initiative to address concerns regarding exposure to toxic chemicals. Proposition 65 requires warning labels on products that contains certain levels of the 600+ elements that the California Air Resources Board considers a carcinogen or a reproductive toxicant. These elements include lead, brass, PVC and a multitude of other everyday elements.
The general Proposition 65 notice is: WARNING: You have purchased an item that may contain a chemical known to the state of California to cause cancer, birth defects or other reproductive harm.
For background on the new Proposition 65 warnings, see https://www.p65warnings.ca.gov/new-proposition-65-warnings.
Proposition 65 and its regulations are posted at https://oehha.ca.gov/proposition-65/law/proposition-65-law-and-regulations.