There are four ways for a chemical to be added to the Proposition 65 list.
1. Labor Code (LC)
Chemicals are added to the list if they are identified by the World Health Organization’s International Agency for Research on Cancer (IARC) as causing cancer in humans or laboratory animals. Proposition 65 says the list “at a minimum” shall consist of chemicals recognized as carcinogens in the California Labor Code, which in turn recognizes carcinogens identified by IARC.
2. State's Qualified Experts (SQE)
Either of two independent committees of expert scientists and health professionals can find that a chemical has been clearly shown to cause cancer or birth defects or other reproductive harm. These two committees—the Carcinogen Identification Committee (CIC) and the Developmental and Reproductive Toxicant Identification Committee (DARTIC) — meet at least once each year and are designated as the “State’s Qualified Experts” for evaluation of chemicals under Proposition 65.
3. Authoritative Bodies (AB)
The CIC and DARTIC have designated certain organizations as “authoritative bodies.” A chemical will be added to the Proposition 65 list if one of these authoritative bodies formally identifies it as causing cancer or birth defects or other reproductive harm.
The following organizations have been designated as authoritative bodies: the US Environmental Protection Agency, US Food and Drug Administration (US FDA), National Institute for Occupational Safety and Health, the National Toxicology Program of the US Department of Health and Human Services, and the World Health Organization’s International Agency for Research on Cancer (IARC).
4. Formally Required to be Labeled (FR)
If an agency of the state or federal government requires that a chemical be labeled or identified as causing cancer or birth defects or other reproductive harm, it will be added to the list. Most chemicals listed in this manner are prescription drugs that are required by the US FDA to contain warnings relating to cancer or birth defects or other reproductive harm.