Prop 65 Short-Form Warning (2024 Amendments)

California's Safe Drinking Water and Toxic Enforcement Act of 1986 (Prop 65) requires a 'clear and reasonable' warning before knowingly and intentionally exposing any individual in California to a listed chemical without first giving a warning. The 2016 regulatory overhaul introduced the 'short-form' warning — a compact label option that could be used without naming the chemical.

The 2016 short-form was intended for products with limited label space. It was rapidly adopted across categories — apparel, electronics, supplements, consumer packaged goods — because it eliminated the need for product-specific chemical determination. OEHHA observed by 2019 that the short-form was being used not because of label-space constraints but to avoid disclosure, and proposed reforms in 2021 that took until December 2023 to finalise.

• Short-form warnings must name at least one listed chemical for each endpoint (cancer, reproductive harm, or both).
• Specific format and signal-word requirements are prescribed for the new short-form.
• The 'WARNING' signal word remains; an exclamation point and the warning symbol (yellow triangle with black '!') are required.
• The URL www.P65Warnings.ca.gov must appear.
• Effective date: 1 January 2025 for new products. Three-year sell-through (products manufactured before 1 January 2025 can carry the old short-form until 1 January 2028).

Examples of compliant new short-form formats:

• '⚠️ WARNING: Cancer Risk From [chemical name] Exposure — www.P65Warnings.ca.gov'
• '⚠️ WARNING: Reproductive Harm From [chemical name] Exposure — www.P65Warnings.ca.gov'
• '⚠️ WARNING: Cancer and Reproductive Harm From [chemical name(s)] Exposure — www.P65Warnings.ca.gov'

The long-form warning — the version used on most products with adequate label space — was unchanged by the amendments. It already required naming at least one chemical for each endpoint. Operators who use the long-form face no compliance gap from the 2024 amendments.

Operators using the short-form must either (a) determine which listed chemical to name and update artwork, or (b) demonstrate they qualify for a safe-harbor exemption (e.g. exposure below the No Significant Risk Level or Maximum Allowable Dose Level for the chemical), or (c) switch to the long-form. The chemical disclosure can drive product reformulation pressure, because brand owners and retailers prefer products that do not require any warning at all.

Brand owners must obtain ingredient- and component-level disclosure from suppliers sufficient to determine which listed chemical, if any, is present at a level requiring warning. This pushes the CoA / SDS / declaration burden upstream. For complex assemblies (electronics, multi-component consumer goods), the determination per SKU can require months of supplier engagement.

Contract manufacturers and private-label suppliers in the dietary-supplement, cosmetic and food spaces now face explicit downstream requests to identify which Prop 65 chemicals are above the safe-harbor levels in their formulations.

Prop 65 is enforced primarily through private-party litigation under the bounty-hunter provision: a private enforcer issues a 60-day Notice of Violation alleging the product was sold in California without a compliant warning, and after 60 days can sue. Settlement values run from low five figures to mid-six figures depending on the alleged exposure and revenue. The 2024 amendments do not change this mechanism; they expand the scope by making old generic short-forms non-compliant after the sell-through period.

Expect a wave of 60-day notices in 2027-2028 targeting products that did not update from the generic short-form during the sell-through window.

1. Inventory every SKU sold into California that carries the generic short-form warning.
2. Confirm with suppliers (CoAs, declarations, SDSs) which Prop 65-listed chemicals are present and at what exposure level.
3. For each SKU, decide: drop the warning (if exposure is below safe harbor), update to the new short-form (naming the chemical), or switch to the long-form.
4. Where reformulation is feasible, evaluate whether removing the listed chemical is cheaper than carrying the warning.
5. Update artwork, sequence the production transition, and document the manufacture date so the three-year sell-through can be claimed.
6. Hold the supporting determination (which chemical, what exposure assessment, what NSRL/MADL was applied) as a controlled record — the defence to a 60-day notice depends on it.

• Assuming the sell-through period applies to products manufactured after 1 January 2025 — it does not.
• Updating artwork but not retaining the chemical-determination record that supports it.
• Naming a chemical without confirming it is actually on the current Prop 65 list.
• Treating exposure assessments as static — the list and safe-harbor levels change.
• Dropping the warning based on exposure below safe harbor without documenting the calculation.
• Inconsistent chemical naming across SKUs (chemical name vs CAS-derived name vs trade name).