Call Us: 415.956.2828

Client Alert: Injunction Casts Doubt on Titanium Dioxide Proposition 65 Cancer Warnings in California

by Alecia E. Cotton and Emily A. Murphy

The future of a Proposition 65 warning required in California for products containing a specific form of Titanium Dioxide is now uncertain as a federal judge has ruled it could be misleading. 

This development has implications for cosmetic and personal care products companies, many of which have faced litigation in recent years for using the chemical in products such as eyeshadow, blushes and sprays.

Proposition 65 and Titanium Dioxide 

Proposition 65 is a decades-old California law that requires businesses to warn consumers of certain chemical exposures that could cause cancer, birth defects or other reproductive harm.  The Office of Environmental Health Hazard Assessment (OEHHA) is tasked with implementing the law. In 2011, OEHHA listed a specific type of Titanium Dioxide that is made of airborne, unbound particles of respirable size as cancer-causing in humans, thereby requiring a Proposition 65 warning on products containing this specific type of Titanium Dioxide.

The Litigation

The Personal Care Products Council (the plaintiff), a nonprofit business association with more than 600 cosmetic industry members, filed a lawsuit arguing California Attorney General Rob Bonta should remove the chemical from the Proposition 65 list of known carcinogens. The plaintiff argues a cancer warning is misleading as the study relied upon by OEHHA in listing Titanium Dioxide was based on the International Agency for Research on Cancer’s (IARC) finding that it was “possibly carcinogenic in humans.” The plaintiff argues that IARC’s conclusion was based on two experiments with rats where the animals were forced to inhale levels of Titanium Dioxide that could not be cleared from their lungs—a condition that does not occur in humans. 

U.S. District Judge Troy L. Nunley in the Eastern District of California has sided with the plaintiff for the time being, issuing a preliminary ruling that there appears to be insufficient evidence to justify the cancer warning. It remains to be seen whether the plaintiff will prevail at trial, as the Attorney General could present further evidence supporting the cancer warning.

Industry Impact

Over 500 Proposition 65 Notices of Violation for Titanium Dioxide have been filed by private enforcers in the last two years alone. Many of these notices have targeted cosmetic and personal care products companies. The Personal Care Products Council v. Rob Bonta injunction temporarily blocks new lawsuits from being filed over the chemical. While the injunction does not expressly halt existing lawsuits, companies may take the position that a stay of such suit is warranted until a final decision is reached in The Personal Care Products Council v. Rob Bonta. 

If you have questions about this alert or any compliance issues related to Proposition 65, please reach out to our Retail practice co-chair, Alecia Cotton ( or Emily Murphy ( in our Retail practice group.

San Francisco, CA
  • Robert Dollar Building
    311 California Street, 10th Floor
    San Francisco, CA 94104-2695
  • Phone: 415.956.2828
  • Fax: 415.956.6457
Washington, DC
  • 1500 K Street, NW, Suite 800
    Washington DC 20005-1227
  • Phone: 202.777.8950
  • Fax: 202.347.8429