Prop 65 Compliance for California Sellers Sourcing from China

If you sell products made in China to customers in California, Proposition 65 probably applies to you. The short version: California requires any business with 10 or more employees to put a "clear and reasonable" warning on products that expose people to any of the 900+ chemicals on the state's list, unless exposure stays below the state's safe harbor levels. Skip the warning when one is required and you open yourself to lawsuits that private plaintiffs can file, with civil penalties up to $2,500 per day per violation.

This guide covers how the law works, the January 1, 2025 warning changes, why China-sourced products get targeted, your three compliance options, smart testing, and what to do when a 60-day notice arrives. CN Ally works with importers sourcing from China every day, and Prop 65 screening is one place where planning upstream saves real money downstream.

How Proposition 65 actually works

Proposition 65 is the public name of California's Safe Drinking Water and Toxic Enforcement Act of 1986. The state's Office of Environmental Health Hazard Assessment (OEHHA) maintains the list of chemicals "known to the state to cause cancer or birth defects or other reproductive harm," now more than 900 substances: solvents, heavy metals, plasticizers, flame retardants, and compounds that show up routinely in manufactured consumer goods.

Three things people consistently get wrong:

It does not ban anything. A product that needs a Prop 65 warning can still be sold in California legally, with the warning. The violation is exposing someone without warning them first, not the presence of the chemical.

The obligation sits on you, not just the factory. Prop 65 applies to everyone in the chain of distribution: manufacturers, importers, distributors, and retailers, including online sellers outside California who sell into the state. When you import from China and sell to Californians, you are in that chain. What your factory knows about California law does not transfer your obligation.

Warnings become mandatory one year after a chemical is listed. The list keeps growing, so a product that was clean two years ago is not guaranteed to be clean today. Watch the list; do not test once and forget about it.

Businesses with fewer than 10 employees are exempt. That exemption is narrower than it sounds: if you are a three-person importer selling through a large retailer, the retailer has its own obligation, and your contracts may pass the problem back to you.

Safe harbor levels are the real question

A warning is required when exposure exceeds the state's safe harbor levels. OEHHA has set more than 300 of them: the No Significant Risk Level (NSRL) for listed carcinogens, and the Maximum Allowable Dose Level (MADL) for listed reproductive toxicants. The NSRL is the daily exposure calculated to cause no more than one extra case of cancer per 100,000 people over a 70-year lifetime. The MADL is set at one-thousandth of the no-observed-effect level.

These levels are far lower than most people expect. Lead, listed for both cancer and reproductive toxicity, has an NSRL of 15 micrograms per day and a MADL of just 0.5 micrograms per day. Keep that number in mind when someone tells you their product "only has a trace of lead." A trace can be enough.

If no safe harbor level exists for a chemical, you cannot assume a small amount is fine. Either demonstrate the exposure poses no significant risk yourself, an expensive scientific exercise, or provide the warning.

The 2025 short-form warning changes (and the 2028 deadline)

The 2018 regulations (Title 27, California Code of Regulations, Article 6) created the modern warning system. In December 2024, California finalized short-form amendments effective January 1, 2025. If you order labels in China, these are the current rules:

• Short-form warnings must now name at least one chemical for each endpoint. The old format could say only "Cancer and Reproductive Harm" with no chemical identified. The new format requires the actual chemical name.
• Label size restrictions were removed. Short-form warnings can go on any label size, as long as the text is at least 6-point font and conspicuous.
• Online warnings got stricter. Warnings must be accessible on the product page before purchase, not buried behind checkout. Retailers get a 60-day grace period to update online warnings when something changes.
• Existing inventory is grandfathered. Products already labeled with the pre-2025 short-form warning can keep selling without relabeling.
• Full transition deadline is January 1, 2028.

The required elements of a compliant short-form warning: the warning symbol (triangle with exclamation point), the word "WARNING," the endpoint (Cancer, Reproductive Harm, or both), the chemical name for each endpoint, and a link to www.P65Warnings.ca.gov. If your packaging carries consumer information in another language, the warning needs to appear in that language too, not just English.

Why China-sourced products get targeted so often

Enforcement is not random. Private plaintiffs, the "bounty hunters" the system is famous for, target products where listed chemicals are predictably present, and China-manufactured goods show up disproportionately because many listed chemicals are exactly what cheap materials and common processes introduce.

The repeat offenders:

Chemical · Where it hides in China-made products

• Lead: Brass hardware and faucets, solder, paint and coatings, PVC stabilizers, fashion jewelry
• DEHP and other phthalates: Flexible PVC: planner covers, phone armbands, shower curtains, vinyl bags, inflatables
• Formaldehyde: Composite wood furniture, wrinkle-resistant textiles, some adhesives
• Cadmium: Fashion jewelry, metal alloys, some pigments
• Bisphenol A (BPA): Polycarbonate plastics, thermal paper receipts
• Flame retardants: Upholstered furniture foam, some electronics housings

One tracked enforcement notice cited lab testing that found DEHP at over 34,000 parts per million in a flexible-plastic organizer sold on Amazon. That is the classic profile: cheap PVC, no chemical specification in the purchase order, and a seller who assumed the factory had it handled.

There is also a legal reason importers cannot plead ignorance. In Lee v. Amazon, a California appellate court held that "constructive knowledge" is enough to trigger the law. You do not need to actually know your product contains a listed chemical; if a person using reasonable care would have known, that counts. Deliberately avoiding information about your product's chemistry is not a defense.

Your three compliance options

Every importer selling into California is choosing one of three strategies, whether they realize it or not.

Option 1: Test and document. Commission lab testing against the relevant listed chemicals, keep the reports on file, and warn only if results exceed safe harbor levels. The most defensible position and the only one that lets you sell without warnings. It costs real money per product and per material change. Right for higher-margin goods, private-label products where warnings would damage the brand, and anything where a warning feels commercially unacceptable.

Option 2: Warn by default. Put a compliant warning on everything you sell in California without testing. Always allowed, and it costs almost nothing. The tradeoff is commercial: a cancer warning on premium packaging changes how the product is received. And under the 2025 chemical-naming rule, a generic warning that names the wrong chemical (or none) is a weaker shield than it used to be.

Option 3: Reformulate and respecify. Work with the factory to remove the listed chemicals at the source: lead-free brass, phthalate-free plasticizers, low-formaldehyde finishes. The only strategy that eliminates the problem permanently, and often cheaper per unit than perpetual testing. It requires a factory willing to change materials and a testing program to verify the change, not just a promise.

Most serious importers land on a mix: reformulate where the chemistry is easy to control (brass, PVC, coatings), test the categories where reformulation is hard or unverifiable, and warn by default only on low-margin SKUs where neither investment makes sense.

How to test without overspending

The law requires a warning or proof of low exposure; testing is how you build that proof. Design the program around risk instead of testing everything blindly.

Test components, not just finished goods. The chemical almost always lives in one component: the brass valve, the PVC handle, the painted surface. Testing the component costs less and tells you more. Ask your supplier for a full component and material list before you test.

Use accredited labs and keep reports dated. A factory's in-house certificate is not a substitute for an independent report with a date on it. File each report with the purchase order it covers, because formulations drift: a factory that passes this year can change a plasticizer supplier next year without telling you.

Target the chemicals that matter for your category. Full-spectrum screening for hundreds of chemicals is overkill. Brass plumbing accessories: test for lead. Flexible PVC goods: test for phthalates. Composite wood furniture: test for formaldehyde. Category-specific testing is how you keep the program affordable, and it mirrors how enforcement works, since plaintiffs test for the chemical they already suspect.

Build chemical attestations into supplier paperwork. Add a Prop 65 attestation to your supplier questionnaire: does this material, at the concentration supplied, contain anything on the current OEHHA list? Require the supplier to update it when their formulation changes, tied to the same change-control process you use for quality. A chemical baseline matters as much as the physical golden sample. Our lab testing guide walks through setting up the testing workflow with Chinese suppliers.

Retest on a schedule, not on a scare. The list grows annually and enforcement plaintiffs buy products off the shelf and test them. Annual or per-production-run testing on your highest-risk SKUs costs less than one settlement negotiation.

The warning label, done right

If testing shows you need to warn, or you choose warn-by-default, the warning has to satisfy the regulations to protect you. A vague "may contain chemicals" sticker does not.

For on-product warnings, the 2025-era short form needs the warning symbol, "WARNING," the endpoint, at least one named chemical per endpoint, and the P65Warnings.ca.gov URL, in at least 6-point conspicuous type.

One rule importers miss: the responsibility shift in the supply chain. Under Section 25600.2, a manufacturer, producer, packager, importer, supplier, or distributor must either affix the warning to the product or give written notice plus warning materials to the retailer's authorized agent, renewed annually (or within 90 days when a new chemical gets added). Retailers are responsible for placing and maintaining the materials they receive. As the importer, you sit upstream: if your retail customers get hit because you never warned them, that failure is yours. When a retailer's only knowledge of an exposure comes from a 60-day notice, it gets five business days to fix it by warning or pulling the product. Give your retailers the materials before that clock starts.

What happens if you ignore it

Enforcement runs through civil lawsuits. The Attorney General, district attorneys, and city attorneys can sue, but most cases come from private plaintiffs acting in the public interest. Before suing, a private plaintiff must serve a 60-day notice on you, the Attorney General, and the relevant district and city attorneys. If no public prosecutor takes the case within 60 days, the private plaintiff can proceed, seeking injunctive relief, civil penalties of up to $2,500 per day per violation, and attorneys' fees.

That 60-day window is your real deadline: investigate the claim, test the product, add a compliant warning, or pull the SKU from California, and respond to the noticing party. OEHHA publishes a small-business guide for 60-day notices. Read it before you need it.

The economics favor plaintiffs, which is why the system works the way it does. Private enforcers keep 25 percent of the penalties they recover, so there is a standing industry of firms that buy products, test them, and send notices. Because of Lee v. Amazon, not knowing is no shield. And because penalties stack per day per violation, a product line selling unwarned for months creates exposure no small importer can comfortably absorb. Most cases settle. The cheapest 60-day notice is the one that never gets sent, because your product was already warned or already clean.

Amazon sellers: the extra layer

If you sell on Amazon, a second compliance system sits on top of California law. Amazon's Proposition 65 policy requires all selling partners, including those with fewer than 10 employees, to determine whether their products contain Prop 65 chemicals and to provide the required warnings. Amazon collects Prop 65 information through its listing system, including specific chemical names, and displays warnings on product detail pages.

Two practical consequences. First, the small-business exemption does not save you on Amazon: the platform policy applies regardless of headcount, and listings without the required disclosures can be suppressed. Second, Amazon listings are public, searchable, and shoppable from California, which makes them a convenient shopping list for enforcement plaintiffs. A noticeable share of recent 60-day notices name Amazon sellers and ASINs directly. Treat Amazon's Prop 65 fields as mandatory, not optional.

Note the useful parallel with the EU side: REACH restricts many of the same substances, but restriction and warning are different regimes. A product can pass REACH and still need a Prop 65 warning, because Prop 65 warns at exposure levels far below most restriction thresholds. Our REACH and RoHS guide covers the European framework if you sell on both sides of the Atlantic.

Frequently asked questions

Do I need Prop 65 testing if my supplier says the product is compliant?

A supplier's verbal assurance is not a test report, and under Lee v. Amazon your obligation is measured by what reasonable diligence would have found. Get the claim in writing as a chemical attestation tied to a specific formulation and date, and verify high-risk categories with independent testing. A factory-wide certificate not tied to your product, your materials, and a current date is not evidence.

Does Prop 65 apply if I only sell online and ship to California?

Yes. The law covers internet and catalog sales into California by businesses located anywhere. Online product pages need the warning displayed before the California buyer purchases, and the physical product should carry the on-product warning too.

What exactly should a Prop 65 warning label say?

Under the 2025 rules, a short-form on-product warning needs the warning symbol, "WARNING," the endpoint (for example, "Cancer and Reproductive Harm"), at least one named chemical for each endpoint, and www.P65Warnings.ca.gov, in at least 6-point conspicuous type. Longer warnings describing the exposure route in more detail also satisfy the law.

Does Prop 65 apply to businesses with fewer than 10 employees?

The statute exempts them from the warning requirements. But the exemption does not protect you from contracts: retailers you supply may require Prop 65 compliance regardless of your size, and Amazon's seller policy requires Prop 65 determinations from every selling partner. If you sell through any larger channel, assume the exemption does not help you.

If my product passed REACH testing, does it still need a Prop 65 warning?

Quite possibly yes. REACH restricts substances above certain concentrations; Prop 65 requires warnings based on exposure relative to safe harbor levels that are often orders of magnitude lower. Lead's reproductive-toxicity safe harbor is 0.5 micrograms per day. Passing a REACH screen does not answer the Prop 65 exposure question.

Can I be sued if I genuinely did not know my product contained a listed chemical?

Yes. California courts have held that constructive knowledge, what you would have known with reasonable diligence, is sufficient. "Nobody told me" is not a defense when the chemistry of your product category is well documented and a test would have found the chemical.

The decision rule: sort every SKU into one of three buckets

Prop 65 compliance does not have to be a research project. Pull your California-bound catalog and put every SKU in one bucket: tested clean (current independent report, below safe harbor, on file), warned (compliant warning on the product and the listing), or unknown. The unknowns are your exposure. For each one, choose: test it, warn on it, or reformulate it. Unknown is not a strategy; it is what plaintiffs get paid to find.

Start with your top sellers by California revenue and your highest-risk materials: anything brass, flexible PVC, painted metal, composite wood, or fashion jewelry. Set a calendar reminder tied to your production cycle to recheck the OEHHA list and your attestations, because the list changes and factories change materials.

If you are sourcing new products from China and want Prop 65 screening built into supplier qualification, sampling, and pre-shipment checks instead of bolted on afterward, talk to CN Ally. Chemical compliance is cheapest at the specification stage, when choosing a different brass alloy or plasticizer costs nothing, and most expensive after the container has landed.