Understanding California's Prop 65: What the Warning Labels Really Mean

Proposition 65, approved by California voters in 1986, obliges companies to post warnings when a product may expose users to chemicals known to cause cancer or reproductive harm above specific limits. The law does not ban those chemicals; it aims to give consumers information to make informed choices and to motivate manufacturers to reformulate. While most warnings reflect actual chemical levels exceeding the safe-harbor thresholds, a minority are issued preemptively.

Critics note that excessive warnings can confuse shoppers, leading the state to require short-form notices that identify at least one chemical by early 2028. Experts recommend evaluating how often a product is used, checking manufacturer testing data, and taking simple steps—like using gloves or washing hands—to reduce exposure. The guidance underscores that the absence of a label does not guarantee a product is free of hazardous substances.