LINCOLN, Neb. (DTN) -- Bayer filed an opening brief in a Supreme Court case that could effectively end state failure-to-warn lawsuits alleging Bayer did not provide cancer warnings on labels for its glyphosate-based Roundup herbicide, ahead of oral arguments scheduled for April 27, 2026.

The company argues the Federal Insecticide, Fungicide and Rodenticide Act, FIFRA, takes precedence over state warning-label laws and, as a result, nullifies non-Hodgkin's lymphoma claims made by alleged cancer victims across the country.

Bayer argues that Congress's original intent of the FIFRA statute was to provide consistency in such labels across the country and that U.S. Environmental Protection Agency's label of Roundup does not stipulate cancer warnings, although it could have been required.

"Once EPA makes that judgment, the label is the law," Bayer said in its opening brief.

"It cannot be second-guessed by lay juries applying the law of 50 states without violating Congress' directive, threatening today's food supply and impeding tomorrow's innovation. Indeed, that 'crazy quilt' of conflicting state regulations is exactly what Congress enacted (FIFRA) to stamp out. Allowing lay juries applying the law of 50 states to second guess EPA's judgments destroys that balance and undermines Congress' goals. Congress protected against such results by preempting claims like Durnell's."

In recent weeks, Bayer announced a $7.3 billion settlement that covers outstanding and future Roundup claims as they pertain to non-Hodgkin's lymphoma claims.

In addition to petitioning the U.S. Supreme Court on a Missouri state failure-to-warn case now before the court, Durnell v Monsanto, Bayer has undertaken a plan to pass legislation in states across the country to protect its interests.

Last summer in the Durnell case, the Missouri Court of Appeals joined the U.S. Court of Appeal for the Ninth and 11th circuits and state appellate courts in California and Oregon in holding that federal law does not preempt state laws. The U.S. Court of Appeals for the Third Circuit ruled the opposite in another case.

In Bayer's brief filed with the Supreme Court, the company said EPA approved the Roundup label without a cancer warning and because the label is the law, "Monsanto is not free to change its labels without first seeking and obtaining EPA approval."

Bayer said Monsanto could not satisfy its state duties without the federal government's "special permission and assistance," which hinges on the EPA's judgment.

"Under the court of appeals' approach, virtually all failure-to-warn claims are 'consistent' with FIFRA's misbranding provision, because virtually all failure-to-warn claims require (as FIFRA's misbranding provision does) the manufacturer to 'adequately warn users of the potential dangers of using its product,'" Bayer said in the brief.

"That approach paves the way for massive variation where Congress demanded uniformity."

CROPLIFE AMERICA AMICUS BRIEF

In an amicus brief filed by CropLife America last week in support of Bayer, the group said the continued use of failure-to-warn claims in state courts would have far-reaching consequences for agriculture.

Although Monsanto has prevailed in most Roundup cases that have gone to trial, CropLife America said, it does not take many large jury awards to endanger the existence of agriculture and the company.

"The threat of such immense liability multiplied across the many pending cases could easily drive an economically vital product off the market, despite EPA's repeated findings that it poses no cancer risk as part of FIFRA's registration and registration review process," CropLife America said.

"Indeed, Bayer has already removed its glyphosate-based products from residential lawn and garden applications. Should the continued risk of large verdicts based on flawed legal theories lead to similar decisions for commercial applications, the result would be devastating to U.S. agricultural production."

Ag chemical manufacturers, the group said, have been put in an "impossible" position with state warning-label laws.

"Dissonant state and federal requirements place manufacturers in an untenable position," CropLife America said.

"It is difficult to imagine, for instance, how a manufacturer could thread the needle between EPA's and Missouri's warning requirements, given that EPA has specifically rejected any cancer warning for glyphosate as mislabeling."

CropLife America said repeated reviews of glyphosate have found no known link to cancer in humans, dating back to Roundup's original registration 50 years ago.

"This extensive review of 'new science' included assessment of 63 epidemiological studies, 14 animal carcinogenicity studies and nearly 90 genotoxicity studies for the active ingredient glyphosate," CropLife America told the court.

"EPA concluded that 'available data and weight-of-evidence clearly do not support the descriptors 'carcinogenic to humans' or 'likely to be carcinogenic to humans.'"

The International Agency for Research on Cancer in 2015 classified glyphosate as "probably carcinogenic to humans." CropLife America told the court that it should give more weight to the work done by the EPA on the glyphosate toxicity question.

The EPA Office of Pesticide Programs sent a letter to all glyphosate registrants in August 2019 reiterating that the agency disagrees with the IARC's assessment of glyphosate.

"EPA noted that its cancer classification is 'consistent with other international expert panels and regulatory authorities,' including government regulators in Canada, Australia and New Zealand, as well as the European Food Safety Authority and European Chemicals Agency," CropLife America said in the brief.

"EPA expressly rejected IARC's cancer conclusion, explaining that EPA's 'cancer evaluation is more robust than IARC's evaluation,' which 'only considered a subset of the studies included in the EPA's evaluation' and included 'some studies that were not appropriate for determining the human carcinogenic potential of glyphosate.'"

Read more on DTN:

"Bayer Settles Roundup Cases for $7.3B," https://www.dtnpf.com/….

Todd Neeley can be reached at todd.neeley@dtn.com

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