What does Proposition 65 require of a supplement brand, and what changes in 2026?

What Proposition 65 requires

California's Safe Drinking Water and Toxic Enforcement Act of 1986, Proposition 65, is administered by the Office of Environmental Health Hazard Assessment (OEHHA). A secondary summary of OEHHA's framework states it plainly: Prop 65 “requires businesses to provide ‘clear and reasonable’ warnings before knowingly and intentionally exposing individuals to chemicals listed as known to the State to cause cancer or reproductive toxicity, unless an exemption applies.” The duty is triggered by exposure, not by intent to sell into the state: a supplement that reaches a California buyer is in scope regardless of where the brand or its manufacturer is located.

For a brand selling on Amazon, this reaches the listing itself. The same summary describes the current internet-sale rule: warning requirements are satisfied “if the full-form or short-form warning is provided only on the product display page, or through another prominently displayed warning provided before the online purchase is completed.” A brand does not need a customer to be in a California warehouse for the duty to apply. A California buyer viewing the listing page is enough.

The “naturally occurring” exemption

A chemical present in a food is not always a Prop 65 “exposure.” OEHHA's current regulatory text, reproduced in the Omnibus 2026 draft package, defines the exemption this way:

“Human consumption of a food shall not constitute an ‘exposure’ for purposes of Section 25249.6 of the Act to a listed chemical in the food to the extent that the person responsible for the exposure can show that the chemical is naturally occurring in the food.” A chemical is naturally occurring “if it is a natural constituent of a food, or if it is present in a food solely as a result of absorption or accumulation of the chemical which is naturally present in the environment”: for example, minerals taken up from soil.

The same text draws a hard line at human activity: “A chemical is naturally occurring only to the extent that the chemical did not result from any known human activity… A listed chemical which has been extracted or concentrated from any source, such as a plant, may be present in a product as the result of human activity even if the extraction or concentration did not change the Chemical Abstract Services Registry Number.” For a botanical extract, that sentence matters: concentrating a naturally-occurring chemical during extraction does not, by itself, keep it inside the exemption.

What Omnibus 2026 proposes to change

On July 22, 2026, OEHHA released draft regulatory text addressing eight topics for discussion at a pre-regulatory public workshop. The two most relevant to a supplement brand are the naturally occurring exemption and internet-purchase warnings:

On the internet-purchase point, the draft text for Section 25602(b) would require a seller to provide “the warning method requirement(s) of Section 25602(a)(3) or (4), andone of the following: (A) a warning on the product display page, or (B) a clearly marked hyperlink… or (C) an otherwise prominently displayed warning provided to the purchaser prior to completing the purchase.” The current rule accepts a product-display-page warning on its own; the draft would pair it with a second, product-level warning method.

This is a pre-rulemaking draft, not a proposed regulation under formal review. OEHHA can revise or drop any topic before a formal rulemaking begins. Two secondary summaries of OEHHA's workshop notice report the written comment deadline differently: one states the comment period is “open through September 8, 2026”; another states comments are due “on or before Monday, September 7, 2026.” Both agree the workshop itself was held July 30, 2026. Confirm the current deadline directly with OEHHA before relying on either date.

What this means for a brand right now

• Nothing in Omnibus 2026 is enforceable yet: it is draft text for a workshop, not an adopted regulation.
• The existing warning duty (Health and Safety Code §25249.6) and the existing naturally occurring exemption already apply today, unchanged by the draft.
• If a listing relies on the internet-purchase provision, the draft signals OEHHA's direction, toward requiring a warning in more than one place, even before any rule takes effect.
• Warning thresholds are chemical-specific numbers, not something to estimate from this article; check the current citation for your product type in the requirements library.

1. Identify which listed chemicals could plausibly be present in your product. Botanical extracts and minerals are the categories OEHHA's naturally occurring exemption most often touches.
2. Check the current limit and citation for your product type at /requirements/prop65/botanical_extract rather than relying on a number from a blog post or a competitor's label.
3. If your product currently relies on the naturally occurring exemption, document why: the exemption is an affirmative showing the responsible party has to make, not a default.
4. Run the free check to see what documentation Amazon's TIC verification process would expect to see alongside a Prop 65 position.

Related: 21 CFR Part 111 explained for brand owners and what your contract manufacturer is responsible for. Compliant Always tracks documentation status; it does not determine your Prop 65 warning obligations.