What Proposition 65 actually requires
A prop 65 plastic warning is a right-to-know label, not a ban notice. California's Proposition 65, the Safe Drinking Water and Toxic Enforcement Act of 1986, requires businesses with ten or more employees to give a clear and reasonable warning before exposing Californians to any of the roughly 900 chemicals OEHHA has listed as causing cancer or reproductive toxicity. The trigger is exposure, not mere presence: a substance only creates a warning duty when the estimated daily exposure exceeds a safe harbor level, a no-significant-risk level (NSRL) for carcinogens or a maximum allowable dose level (MADL) for reproductive toxicants. The warning therefore says something about exposure potential, not about illegality.
Which plastic-related chemicals trigger the prop 65 plastic warning
The listed chemicals that matter most for plastic products cluster into a handful of families. Soft PVC is the classic exposure route through phthalate plasticisers; polycarbonate and epoxy-lined packaging raise bisphenol questions; pigments, stabilisers and recycled content carry heavy metals.
| Chemical | Where it appears in plastics | Safe harbor (daily exposure) |
|---|---|---|
| DEHP, DBP, BBP, DINP | Phthalate plasticisers in flexible PVC cable, bags, grips and tool handles | MADL 410, 8.7 and 1200 µg/day respectively; DINP NSRL 146 µg/day |
| Bisphenol A (BPA) | Polycarbonate, epoxy can coatings and some resins | Dermal MADL 3 µg/day |
| Bisphenol S (BPS) | BPA-free replacement polymers | Listed December 2025; warning duty from December 2026 |
| Lead, cadmium | Pigments, stabilisers, solder and recycled content | Oral NSRL 0.5 µg/day (lead); 4.1 µg/day (cadmium) |
| Styrene, formaldehyde | Polystyrene, laminates and some adhesives | Listed; exposure depends on the use case |
The warning format rules that changed in 2018 and 2025
Since 30 August 2018 a compliant warning must begin with the word WARNING, carry the yellow triangle symbol, name at least one listed chemical and point to www.P65Warnings.ca.gov. The newer warning-methods regulation took effect on 1 January 2025 with full enforcement from 1 January 2028, giving sellers more flexibility in how the warning is delivered: on the product, on packaging, on a shelf tag or through a digital receipt, as long as it stays clear and reasonable at the point of purchase. For a california export program, that means a label designed to the 2018 safe-harbor wording still works across retail and online listings.
Why california export buyers get caught
Enforcement comes from the Attorney General and from private plaintiffs who file 60-day notices of violation. Settlements across handbags, stationery, beauty tools and automotive accessories have made a single-phthalate concentration of 1,000 ppm, or 0.1 percent, the de facto industry benchmark. Cross-border e-commerce sellers are frequent targets because the listing, not the factory, is named. The practical exposure for a buyer is a settlement bill plus re-labelling plus re-inspection, not a product seizure, which is why the cheapest insurance is sorting compliance out before the first purchase order.
How exposure is estimated, and why content alone is not the test
Safe harbor levels are daily exposure doses, not content limits. A substance locked inside a polymer matrix may never reach the user, while a mobile additive in a flexible grip releases readily. Laboratories therefore measure migration under simulated use, and the calculation weighs contact type (oral, dermal or inhalation), contact duration and surface area. A PVC grip held for minutes a day and a food-contact film used daily produce very different daily exposures from the same starting concentration, so a total-content test alone cannot settle the question either way.
A practical compliance route for plastic products
Proposition 65 compliance is mostly an evidence problem: you need to show, not assert, that exposure stays under the safe harbor levels. The sequence below keeps the workload proportionate to the risk in each component.
- Collect material declarations and, for suspect chemistries, third-party migration or content testing against the NSRL and MADL.
- Decide warn-or-reformulate early; for many components reformulation is cheaper than a lifetime label.
- Re-check the list at least twice a year, because OEHHA adds chemicals several times a year and BPS-type additions land fast.
- Keep test reports with the listing, since marketplaces and plaintiffs both ask for evidence, not assurances.
Treat Proposition 65 as one layer of a wider compliance stack. The FDA and LFGB food contact guide and the EU food contact regulation 10/2011 article cover the other two big destination regimes, while the EU PPWR explains the packaging-side changes now landing in Europe. Raw material grades and their compliance documents are indexed under plastic materials.
