Who Controls When State and Federal Regulators Disagree on Whether a Chemical Is a Carcinogen?


  • California AG Xavier Becerra filed an amicus brief in the California Court of Appeal in support of the plaintiff’s position in Johnson v. Monsanto Co., Nos. A155940 & A156706, arguing that the designation of certain chemicals as carcinogens and the requirement to include warnings about them under California’s Safe Drinking Water and Toxic Enforcement Act of 1986 (“Proposition 65”) is not preempted by federal law.
  • In the lower court, a jury found that the plaintiff had developed non-Hodgkin’s lymphoma as a result of using Monsanto’s weed killer Roundup, which contains glyphosate, a chemical designated as a carcinogen by California but not by the federal Environmental Protection Agency. On appeal, Monsanto argued that Proposition 65 is preempted by the Federal Insecticide, Fungicide, and Rodenticide Act (“FIFRA”).
  • In the amicus brief, AG Becerra argues that the duty to warn under Proposition 65 is not preempted because it is fully consistent with FIFRA in that it requires that pesticides not be misbranded; there is no conflict between the state and federal laws because FIFRA does not address point-of-sale warnings; and that federal preemption of state laws protecting public health is generally disfavored.