California Proposition 65

Proposition 65 (Prop 65) is the original name for the ballot initiative that became California’s Safe Drinking Water and Toxic Enforcement Act of 1986. It is administered by the Office of Environmental Health and Hazard Assessment (OEHHA) a part of the California Environmental Protection Agency (Cal/EPA).

The Prop 65 regulation states that “no person, in the course of doing business, may knowingly and intentionally expose any individual to a Proposition 65 listed chemical without first giving clear and reasonable warning to that individual”.

Under Prop 65, the Governor of California must issue an annual list of substances “known to the State” to cause cancer, birth defects or reproductive harm.  Currently, there are more than 800 substances on this list, including additives or ingredients in food and many common household products, naturally occurring substances, ethyl alcohol in alcoholic beverages, aspirin, and many prescription drugs. Prop 65 requires anyone doing business in California to label a product if human exposure to a listed substance in the product is expected to be at a level that would cause an unreasonable risk. For certain products, this level is identified with a published “safe harbor” value. For the vast majority of substances listed on Prop 65, a safe harbor level has not been published.

A Prop 65 listing is not a safety determination
and does not mean that a product is in
violation of any product-safety standards.”

A business has a “safe harbor” from Prop 65 warning requirements if exposure to a substance occurs at or below the identified “safe harbor level” for that chemical.

  • For substances that are listed as causing cancer, the “safe harbor” level is called a “no significant risk level” (NSRL).  An NSRL is defined as the level of exposure that would result in not more than one excess case of cancer in 100,000 individuals exposed to the substance over a 70-year lifetime.  In other words, a person exposed to the substance at the “no significant risk level” for 70 years would not have more than a “one in 100,000” chance of developing cancer as a result of that exposure.
  • For substances listed as causing reproductive or developmental toxicity, the safe harbor level is called a “maximum allowable daily limit (MADL). A MADL is defined as the “no adverse effect level” (NOAEL) from animal studies divided by 1000.

In order to assess the need for warnings under Prop 65, various pieces of information about the listed chemical are needed e.g. the established safe harbor level and various physicochemical properties. These data are used to determine whether the estimated exposure to a human from a product containing a listed chemical is above or below the safe harbor level for that chemical.

It is also important to note that a Prop 65 listing is not a safety determination. Indeed, according to OEHHA, the purpose of Prop 65 is to notify consumers that they may be exposed to a listed substance, but a Prop 65 product warning label does not mean that a product is in “violation of any product-safety standards.” The Prop 65 warning requirements can be enforced through civil lawsuits brought by the California Attorney General, certain district and city attorneys, or private parties acting in the public interest. As stated by OEHHA, Prop 65 “does not ban or restrict the use of any given chemical.” It is not a regulation or a restriction on use, it is a labeling requirement that applies in certain instances. Lastly, Proposition 65 is a California law, and its list does not affect other U.S. states or European, Latin American, Canadian, or Asia Pacific regulations.