The U.S. Supreme Court on Thursday sided with pesticide manufacturer Monsanto in a closely watched Roundup case, ruling that federal law overrides state claims that the company failed to warn consumers about cancer risks associated with its products.
The 7-2 decision in Monsanto v. Durnell overturns a Missouri verdict won by St. Louis gardener John Durnell, who argued years of exposure to the herbicide contributed to his non-Hodgkins lymphoma. The court ruled that states cannot require product warnings that exceed U.S. Environmental Protection Agency regulations. It approved Roundup in 1974 and stated it posed no adverse health effects when used as directed.
However, glyphosate, the active ingredient in Roundup, has been classified as “probably carcinogenic to humans,” since 2015 by the World Health Organization.
The ruling carries significance for agricultural states like Illinois, one of the nation’s largest producers of corn and soybeans and among the heaviest users of glyphosate-based herbicides such as Roundup. Some rural Illinoisans have faced long-term exposure to the weedkiller. In a previous interview with the Tribune, organic farmer Harold Wilken talked about how he believes years of Roundup use contributed to his tonsil and lymph node cancer.
For farm advocacy groups that filed briefs in the case, the decision raises concerns that federal regulatory approval may now make it harder to bring state consumer protection claims.
“Today’s Supreme Court decision in Monsanto v. Durnell is harmful to farmers and farmworkers,” said Nathan Leys, staff attorney with FarmSTAND, a legal advocacy group. “Farmers and farmworkers have made clear that Monsanto does not speak for them when the company says it needs impunity.”
In April, Illinois Attorney General Kwame Raoul joined a coalition of 17 attorneys general in an amicus brief urging the court to reject Monsanto’s argument, warning it would undermine states’ ability to protect consumers and provide legal remedies for residents harmed by products sold within their borders.
The ruling is expected to limit tens of thousands of similar lawsuits nationwide and marks a major legal victory for Monsanto parent company Bayer, a German-based agricultural science company, which has spent billions of dollars defending and settling Roundup-related cancer claims.
“The ruling should result in the dismissal of current warning-based claims and bar future failure-to-warn claims,” Bayer said in a statement Thursday, calling the decision “good for science, farmers and industries that depend on regulatory clarity for innovation.”
What began as a dispute over one Missouri cancer case may sharply limit how residents of Illinois and other agricultural states seek accountability when they believe federally approved products have caused injury, critics say.
“Today’s ruling allows Monsanto and other chemical companies to avoid responsibility when their labels leave people unprotected from serious harm,” said Patti Goldman, senior attorney at Earthjustice in a statement Thursday.
“The fact that EPA-approved labeling exists does not mean a product is safe, and it should not become a shield for companies that fail to warn about cancer risks, neurological harm and other serious dangers,” Goldman added.
The U.S. EPA evaluates and registers all pesticides sold or used under its Federal Insecticide, Fungicide and Rodenticide Act, or FIFRA. Although Roundup remains widely used in agriculture since its EPA registration in 1974, Bayer removed its glyphosate-based product for residential lawn and garden use in 2023 following thousands of legal claims that the weedkiller caused cancer.
In his majority opinion, Justice Brett Kavanaugh said that the federal law “preempts Durnell’s state-law failure-to-warn claim because the claim would require Monsanto to add a cancer warning to Roundup’s label.”
Opponents argue that reasoning leaves consumers with fewer avenues to seek compensation.
“Many in rural communities may get sick as a result of Roundup exposure in the future,” said David Muraskin, FarmSTAND’s managing director of litigation. “It’s harmful to the fight for a better food system if lawyers ignore the voices of farmers and farmworkers in service of deals to release Monsanto from liability.”
In her dissenting opinion, Justice Ketanji Brown Jackson, joined by Justice Neil Gorsuch, argued that Missouri’s failure-to-warn claim was consistent with federal law and that the majority’s approach left injured individuals without a remedy.
“In accepting Monsanto’s argument and holding that Durnell’s failure-to-warn claim is preempted, the Court misunderstands FIFRA’s requirements, misinterprets the scope of FIFRA’s preemption, and ultimately leaves Durnell without a remedy for the significant harms he has suffered,” Justice Jackson wrote.
Durnell’s counsel, Ashley Conrad Keller, did not immediately respond to a request for comment from the Tribune.
The ruling is expected to shape pesticide litigation for years to come.
Stronger regulations may have to come from Congress. The House of Representatives stripped provisions that would have protected pesticide manufacturers from the Farm Bill before passing it in April. The bill is still being considered by the Senate.
