California Prop 65 Warning Text: Formats, Symbol, and Placement

A compliant California Prop 65 warning text must name at least one listed chemical, state that it is known to the State of California to cause cancer or reproductive harm (or both), and direct the reader to www.P65Warnings.ca.gov. That text has to be preceded by a yellow triangle symbol with a black exclamation point and a bold signal word reading “WARNING,” “CA WARNING,” or “CALIFORNIA WARNING.” The regulations give you two safe harbor formats to choose from: a long form and a short form.

The Long-Form Safe Harbor Text

The long-form warning is the standard. The exact wording depends on which health endpoint applies.

For a product containing a listed carcinogen: “This product can expose you to chemicals including [name of chemical], which is [are] known to the State of California to cause cancer. For more information go to www.P65Warnings.ca.gov.”¹

For a reproductive toxicant: “This product can expose you to chemicals including [name of chemical], which is [are] known to the State of California to cause birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.”¹

When both endpoints apply, you have to identify at least one chemical for each. If different chemicals cause each risk, name both. If a single chemical causes both, combine the endpoints into one sentence: “This product can expose you to chemicals including [name of chemical], which is [are] known to the State of California to cause cancer and birth defects or other reproductive harm.” When only one chemical triggers the warning, you can drop the phrase “chemicals including” entirely.¹

The Short-Form Safe Harbor Text

The short-form warning is a condensed version meant for products where label space is tight. It still has to name at least one chemical. For a carcinogen, either of these phrasings works:

“Cancer risk from exposure to [name of chemical]. See www.P65Warnings.ca.gov.”
“Can expose you to [name of chemical], a carcinogen. See www.P65Warnings.ca.gov.”

For reproductive toxicants, the short-form follows the same pattern, substituting “reproductive harm” for “cancer.” When both endpoints apply, name a chemical for each.¹

The 2025 Amendment and the 2028 Deadline

The requirement to name a chemical in the short-form is new. Before January 1, 2025, a short-form warning could say something generic like “Cancer” or “Reproductive Harm” without naming any chemical at all. The amended regulation took effect on January 1, 2025, and businesses already using the old short-form have a three-year transition window. On January 1, 2028, the old format loses its safe harbor protection.² If you are designing new labels or packaging now, use the updated format.

The Symbol and Signal Word

Every safe harbor warning, long or short, needs two visual elements set before the text itself.

The symbol is a black exclamation point inside a yellow equilateral triangle with a bold black outline. If the label is not printed in color, a black-and-white version is acceptable. The symbol goes to the left of the warning text and must be at least as tall as the word “WARNING.”³

The signal word appears in all capital letters and bold print. You can choose “WARNING,” “CA WARNING,” or “CALIFORNIA WARNING.” Any of the three satisfies the requirement.¹

Where and How the Warning Must Appear

Getting the words right is only half the job. The warning also has to reach the consumer in a way that is prominent and legible before the sale. Different sales channels follow different rules.

Product Labels and Packaging

For most consumer products, the warning goes directly on the label or packaging. Short-form warnings on labels must appear in type no smaller than 6-point, and the warning must be conspicuous compared to other text on the label. A tiny warning buried in a dense ingredient list would not qualify even at 6-point.⁴

Shelf Signs and Point-of-Sale Tags

When a warning cannot sit on the product itself, signs or shelf tags at the display or sale point can carry it. Sign requirements vary by product category and exposure type. Some product-specific regulations call for signs as large as 8.5 by 11 inches with a minimum of 20-point type. Position matters: the sign has to be where a customer is likely to see it before deciding to buy.

Environmental Exposures

For locations where people are exposed to listed chemicals in the environment, like parking garages, factories, or amusement parks, the warning must be posted at every public entrance in type no smaller than 72-point. The sign has to identify at least one source of exposure and appear in English plus any other language used on other signage in the area.⁵

Internet and Catalog Sales

Online sellers must display the warning on the product page or provide a clearly marked hyperlink using the word “WARNING” that takes the buyer to the full warning text. Either way, the warning has to reach the customer before the sale is completed. Catalog sellers must include the warning in the catalog itself, clearly tied to the specific product.¹

When a Warning Is Actually Required

A product containing a listed chemical does not automatically need a warning. The obligation applies only when a business knowingly and intentionally exposes someone to a listed chemical and the exposure exceeds the safe harbor threshold set for that chemical.⁶

For carcinogens, the threshold is the No Significant Risk Level (NSRL): the daily intake calculated to produce no more than one additional cancer case per 100,000 people exposed over a 70-year lifetime. Exposures at or below the NSRL require no warning.⁷

For reproductive toxicants, the threshold is the Maximum Allowable Dose Level (MADL), calculated by taking the highest dose that produced no observable reproductive effect in studies and dividing by 1,000. Exposures at or below the MADL are also exempt.⁷

Two exemptions sit outside the threshold analysis. Businesses with fewer than 10 employees are exempt from the warning requirements entirely, as are government agencies and public water systems.⁷ And eating a food product does not count as an “exposure” when the listed chemical occurs naturally in the food, meaning it is a natural constituent or was absorbed from the natural environment through geologic processes rather than introduced through pollution or manufacturing. If a chemical is partly natural and partly introduced by human activity, only the human-caused portion counts. Businesses claiming this exemption have to prove the chemical is naturally occurring and show they used good agricultural or manufacturing practices to keep contamination as low as feasible.⁸

Manufacturer or Retailer: Who Writes the Warning

Primary responsibility sits with the business that makes, imports, packages, or distributes the product. That business can discharge the duty in one of two ways: label the product directly, or send a written notice to the retailer with all necessary warning materials, including labels, shelf signs, or internet warning language.⁹

A manufacturer’s written notice has to identify the specific product, name the listed chemicals involved, and include all warning materials the retailer needs. The notice must be renewed annually for as long as the product is sold in California, and the manufacturer has to get written or electronic confirmation of receipt. If the chemical or health endpoint changes, an updated notice goes out within 90 days.⁹

Retailers become directly responsible in limited situations: when they sell a product under their own brand, when they add a listed chemical to the product themselves, when they cover or alter a warning label, when they receive proper notice and materials but fail to display them, or when no upstream supplier exists and the retailer has actual knowledge of the exposure.⁹

What a Non-Compliant Warning Costs

Civil penalties run up to $2,500 per violation per day for each day the exposure continues without a proper warning.¹⁰ For a product that has been on shelves for months or years with a defective label, that daily accumulation adds up fast.

Enforcement comes from the California Attorney General, district attorneys, city attorneys, and private enforcers acting in the public interest.¹¹ Most cases are brought by private enforcers and most resolve through settlement, with the business paying civil penalties, reimbursing the enforcer’s attorney fees, and agreeing to reformulate or relabel. For small businesses, legal fees alone often exceed the penalties, which is why the warning text is worth getting right the first time rather than correcting after a notice arrives.

1
Cornell Law Institute. California Code of Regulations Title 27 25603 – Consumer Product Exposure Warnings Content
2
Office of Environmental Health Hazard Assessment. Proposition 65 Clear and Reasonable Warnings – Safe Harbor Methods and Content
3
Proposition 65 Warnings. Warning Symbol
4
Office of Environmental Health Hazard Assessment. Regulations on Proposition 65 Title 27, Division 4
5
Cornell Law Institute. California Code of Regulations Title 27 25604 – Environmental Exposure Warnings
6
California Legislative Information. California Health and Safety Code 25249.6 – Required Warning Before Exposure to Chemicals Known to Cause Cancer or Reproductive Toxicity
7
Office of Environmental Health Hazard Assessment. Fact Sheet on Proposition 65 Safe Use Determination Process
8
Office of Environmental Health Hazard Assessment. Regulations on Proposition 65 Title 27, Division 4 – Section 25501
9
Cornell Law Institute. California Code of Regulations Title 27 25600.2 – Responsibility to Provide Consumer Product Exposure Warnings
10
Proposition 65 Warnings Website. What Are the Penalties for Violating Proposition 65
11
California Legislative Information. California Health and Safety Code 25249.7