California Proposition 65
LAST UPDATED · August 2026
Proposition 65 is a California law that requires businesses to provide warnings about exposure to chemicals that the State of California has determined can cause cancer, birth defects, or other reproductive harm. The list, maintained by the California Office of Environmental Health Hazard Assessment (OEHHA), now includes over 900 chemicals and is updated at least once a year.
Why this warning appears
Some CoreLabs dietary supplements contain — or may contain trace levels of — one or more Proposition 65 listed chemicals. A warning is required even when exposures are far below levels that have been shown to cause harm, and even when the listed substance occurs naturally in soil, water, or plant material and is not added by us. California's standards for reproductive toxicants (such as lead) are among the most stringent in the world and are set at levels that include a large margin of safety.
Lead and other naturally occurring elements
Many plant-derived ingredients and minerals draw up trace amounts of lead, cadmium, and arsenic from soil and water as part of natural growth. Because CoreLabs products use real botanical and mineral ingredients, trace levels of these naturally occurring elements may be present. We test every batch and these levels are consistently below federally recognized safety thresholds, but California's Proposition 65 threshold for lead (0.5 µg/day, the "Maximum Allowable Dose Level") is roughly 12 times lower than the federal limit and can be exceeded by trace amounts that are a normal part of mineral-rich supplements.
What the warning means
A Proposition 65 warning does not mean a product will cause harm, and it is not a statement that the product is unsafe. It means the product contains a listed chemical at a level that requires a warning under California law. Many everyday foods and supplements would require a similar warning if sold in California.
Where to learn more
The full list of Proposition 65 chemicals and additional information is published by OEHHA at oehha.ca.gov/proposition-65. If you have questions about a specific CoreLabs product, contact us at support@corelabs.co.
Our testing standard
Every CoreLabs product is third-party tested for heavy metals, microbes, and identity, and a full Certificate of Analysis is published on each product page. A Proposition 65 warning reflects California's legal threshold — not the results of our safety testing.