Is a Proposition 65 warning required? This is the question plumbing product manufacturers, distributors and retailers must ask themselves when doing business in the state of California.

Proposition 65, also known as the Safe Drinking Water and Toxics Enforcement Act of 1986, is a regulation administered by the California Office of Environmental Health Hazard Assessment (OEHHA).  It requires companies with 10 or more employees that sell products in California to provide adequate warning about the presence of certain hazardous chemicals in their products. According to the state, “significant exposure” to these chemicals are “known to cause the risk of cancer, birth defects or other reproductive harm.” OEHHA maintains, publishes and updates a list of these chemicals on a regular basis. Today, nearly 1,000 substances make up this list.