Proposition 65 (Prop 65), also known as the Safe Drinking Water and Toxic Enforcement Act of 1986, is a California state law that requires businesses to provide warnings to consumers about exposures to chemicals that are known to cause cancer, birth defects, or other reproductive harm.
Yes, Prop 65 is a California state law. The impact extends beyond the state because many manufacturers and retailers apply the Proposition 65 warnings to products sold nationwide, rather than maintaining separate labeling for California. Prop 65 applies to any products sold in California regardless of where they were manufactured as well.
Prop 65 applies to a wide range of products, including dietary supplements. If a dietary supplement contains chemicals above the listed safe harbor level as noted by the State of California at https://oehha.ca.gov/proposition-65/proposition-65-list, they must have the proper warning on the label.
There are approximately 900 chemicals in Prop 65, but there are some that are commonly found in dietary supplements that may require a warning. Some examples include heavy metals, phthalates, residual solvents, pesticides, acrylamide, dioxins, and PCBs.
Specific compounds you should test for vary depending on the ingredients and formulation of the supplement. It is ideal to consult with a qualified laboratory or regulatory expert for guidance tailored to your specific product. The most common compounds to consider for dietary supplements are the heavy metals below.
The permissible limits for Proposition 65 chemicals, also known as the "safe harbor levels," are established by the California Office of Environmental Health Hazard Assessment (OEHHA). These safe harbor levels indicate the maximum allowable exposure to a particular chemical without requiring a warning label. The safe harbor levels can vary depending on the specific chemical and the route of exposure (e.g., oral ingestion, dermal contact, inhalation).
These safe harbor levels can change over time as new scientific research becomes available. The OEHHA regularly reviews and updates these levels based on the latest scientific data.
Testing for heavy metals in dietary supplements requires advanced and specific analytical methods performed by qualified and experienced laboratories. In order to test at low levels required in Prop 65, most laboratories use Inductively Coupled Plasma Mass Spectrometry (ICP-MS). This is a highly sensitive and accurate technique used to measure trace levels of metals in a variety of dietary supplements.
When considering testing for heavy metals in dietary supplements, it is important to: