Cosmetics Trade Association Launches Landmark Proposition 65 Suit in California

On March 2, 2026, the Personal Care Products Council (PCPC) lodged a major constitutional challenge to the application of Proposition 65 to a common cosmetic ingredient called diethanolamine, or DEA. 

DEA is an alkanolamine used in cosmetic and personal care formulations as an emulsifier, pH adjuster, and stabilizer for foams. It also appears in DEA-derivatives and fatty acid condensates (e.g., cocamide DEA) that function as surfactants.

California's Safe Cosmetics Program currently identifies more than 2,500 products containing DEA or DEA-related compounds. PCPC seeks to enjoin California and private litigants from enforcing Proposition 65 warnings against cosmetics and personal care products containing DEA.

What Is Proposition 65?

California’s Safe Drinking Water and Toxic Enforcement Act of 1986, better known as Proposition 65, requires businesses that sell consumer products—including cosmetics and personal care products—to notify Californians about certain chemicals that are in those products. The state’s Office of Environmental Health Hazard Assessment (OEHHA) administers the law. The law provides private parties with the right to file actions to enforce Proposition 65, provided that private enforcers first issue pre-suit notices at least 60 days in advance of filing suit.

Pursuant to Proposition 65, California’s state government published a list of substances known to the state to cause cancer or reproductive toxicity. This Proposition 65 List of chemicals is available via the OEHHA website. Listing and delisting chemicals involves a public notice and comment process. There are hundreds of substances on the Proposition 65 list, including DEA.

OEHHA’s Proposed NSRL for DEA (Dermal)

In August 2025, OEHHA proposed to adopt a No Significant Risk Level (NSRL) for dermal exposure to DEA by amending Title 27, California Code of Regulations, section 25705(b). The proposal identified an NSRL of 6.4 micrograms per day for dermal exposure to DEA. This proposed value does not apply to non‑dermal routes of exposure.

The NSRL represents a daily exposure associated with no more than one excess cancer case in 100,000 individuals over a 70-year lifetime. If product-specific exposures are at or below the NSRL, a Proposition 65 cancer warning is not required. 

What Is the Case About?

PCPC contends that there is no scientific evidence suggesting a causal relationship between DEA in cosmetic and personal care products and cancer risks in humans. Nonetheless, private enforcers have sent legal threats regarding DEA and DEA-related compounds to more than 1,400 businesses, generating millions of dollars in settlements and legal fees.

According to the Complaint, Proposition 65 warnings for DEA hurt both businesses and the public. Businesses must “either take action to provide false, misleading, and highly controversial warnings to California consumers about the safety of their cosmetic and personal care products, or face potential costly enforcement actions” from the state or private enforcers. Meanwhile, the public is being misled “about the risks posed by cosmetic and personal care products containing DEA, potentially frightening them away from using a variety of safe products they may have been using for years or increasing their anxiety about the risk of cancer from common household products.”

PCPC lodged two causes of action for violations of the First Amendment, namely that the Proposition 65 warnings amount to compelled false speech in violation of the First Amendment and that the flood of scientifically unsupported warnings undermines public trust in the warnings that truly matter.

What’s Next?

The case, Personal Care Products Council v. Bonta, No. 2:26-at-00393, was filed in the U.S. District Court for the Eastern District of California. While the case is at its early stages, the suit represents a significant challenge to the Proposition 65 landscape as it relates to DEA and cosmetic and personal care products.

If you have any questions concerning the developments discussed in this Update, please contact members of Perkins Coie’s Food & Consumer Packaged Goods Litigation team.