Friday, Jul 3, 2026
Does Monsanto v. Durnell bar California from adding its own health warnings to pesticide labels?
Monsanto v. Durnell bars all sub-national entities, including California, from adding health warnings to pesticide labels different from the federal government’s.
Missouri farmer John Durnell held he’d developed cancer after using Monsanto’s Round Up and sued the company for not disclosing the pesticide’s alleged cancer risk on the product label.
Missouri’s “strict liability” doctrine holds companies legally accountable for failing to warn about the dangerous nature of a product. On those grounds, Durnell was awarded $1.25 million dollars by a Missouri jury.
The decision was appealed to the U.S. Supreme Court, which ruled against Durnell, holding in a 7-2 vote that under federal law, states cannot impose labeling requirements “in addition to or different from” those required by the U.S. Environmental Protection Agency.
While the EPA and European Union agencies have stated Round Up is unlikely to be carcinogenic, the World Health Organization has deemed it “probably carcinogenic to humans.”
This fact brief is responsive to conversations such as this one.
Sources
- Supreme Court of the United States: Monsanto Co. v. Durnell
- Revisor of Missouri: Strict liability for failure to warn
- European Food Safety Authority: Glyphosate: EFSA updates toxicological profile
- U.S. Environmental Protection Agency: Glyphosate
- World Health Organization: IARC Monograph on Glyphosate
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