German chemical giant Bayer has lost an appeal challenging the outcome of the first case to go to trial in the USA over the company’s Roundup weedkiller, France 24 reported on 21 July.

Although the firm lost the appeal, France 24 said the court had reduced the punitive damages awarded to the plaintiff Dewayne ‘Lee’ Johnson, a school groundskeeper and heavy user of Roundup.

Johnson had sued Monsanto – a subsidiary of Bayer – in a landmark case after contracting non-Hodgkin’s lymphoma.

In 2018, a jury had found that the herbicide substantially contributed to Johnson’s illness and had awarded him nearly US$40M in compensatory damages and US$250M in punitive damages that were later reduced to US$78.5M.

The ruling had been followed by a series of lawsuits that have troubled the company since its 2018 takeover of global agrochemical firm Monsanto.

Under the latest ruling on 20 July by the California Court of Appeals, the court had denied Monsanto’s motion for a new trial on condition that Johnson accepted a settlement of US$10.2M in compensatory damages and the same amount in punitive damages.

"Although we have concluded that a reduction in the damages awarded is appropriate, we do not otherwise reverse the judgement," the three-judge panel were reported as saying, affirming Monsanto's liability in the case.

"In our view, Johnson presented abundant – and certainly substantial – evidence that glyphosate, together with the other ingredients in Roundup products, caused his cancer," the judges were reported as saying in their ruling. "Expert after expert provided evidence both that Roundup products are capable of causing non-Hodgkin's lymphoma and caused Johnson's cancer in particular."

In a statement, Bayer was reported by France 24 as saying that the ruling was a "step in the right direction".

"We nevertheless still believe that the jury ruling and the indemnity payments are not compatible with the presented evidence and the existing laws," the company said.

"Monsanto will examine its legal options, including an appeal to the Supreme Court of California," Bayer added in the statement.

In June, Bayer said it would pay more than US$10bn to settle most of the 125,000 Roundup lawsuits it faces in the USA. The firm, which had not admitted any wrongdoing as part of the settlement package, denies claims that Roundup or its active ingredient glyphosate causes cancer, saying decades of independent studies had shown the product is safe for human use.

The product is used by farmers in combination with the company’s genetically modified seeds.