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OEHHA Issues Notice of Intent for Cancer Drug

The California Office of Environmental Health Hazard Assessment (OEHHA) issued a notice of intent to list bevacizumab as a substance known to cause reproductive toxicity under Proposition 65. Bevacizumab is prescribed for the treatment of certain cancers, including metastatic colon cancer. It is a vascular endothelial growth factor-directed antibody. The drug has been identified as causing a risk of reproductive harm by the US Food and Drug Administration (FDA). The label accompanying bevacizumab notes that use of the drug may increase the incidence of ovarian damage and cause harm to an affected fetus.

OEHHA’s listing of bevacizumab falls under the category of substances “Formally Required to Be Listed or Identified.”  This designation is one of four methods under which a chemical can be added to the Proposition 65 list. The other three listing methods for chemicals include: (i) the Labor Code listing mechanism, (ii) the State’s Qualified Experts mechanism, or (iii) the authoritative bodies mechanism.

The final method of listing – “Formally Required to Be Listed or Identified” -is typically applicable to prescription drugs that contain warnings issued by the FDA related to the development of cancer, birth defects or reproductive harm. Under the implementing regulations governing this designation (Section 25902), a chemical is required to be listed under Prop 65 when it has been “formally required” to be identified by a state or federal agency as carcinogenic or causing reproductive toxicity. In the regulations, the formal requirement refers to a compulsory instruction, order or command that has been established by a local or federal agency of the government. The labeling requirement refers to a warning message about the cancer-causing or reproductive toxicity of the chemical being printed on the container. The law also provides a methodology for reconsidering the designation of a chemical under the “Formally Required to be Labeled” category.

For prescription drugs, Proposition 65 regulations state that “the labeling approved or otherwise provided under federal law and the prescriber’s accepted practice of obtaining a patient’s informed consent comply with” the safe harbor warning requirements (and therefore are considered clear and reasonable as a matter of law). Thus, even if bevacizumab is listed, it is unlikely that separate Proposition 65 warnings would be considered necessary.

Grimaldi Law Offices has been advising clients for over 20 years on chemical and product law. For knowledgeable advice and in-depth analysis on your Prop 65 compliance obligations, contact Grimaldi Law Offices at (415) 463-5186 or email us at [email protected].


Ms. Grimaldi maintains a diverse environmental law practice focusing on chemical and product regulation and litigation defense. Her practice areas include Proposition 65, California's Safer Consumer Products Regulations, California's Rigid Plastic Packaging Container Act and the federal Toxic Substances Control Act. Ms. Grimaldi graduated from the University of California Hastings College of the Law magna cum laude and holds a Bachelor of Science Degree in Bacteriology from University of California, Davis. Prior to attending law school, she worked as a research assistant in laboratories at the University of California, San Francisco Cancer Research Institute and at the University of California, San Francisco School of Medicine.