German agrochemical giant Bayer has won five consecutive trials in the US over claims that its glyphosate-based weedkiller Roundup causes cancer.

On 1 September, a jury returned a verdict in favour of the company following a three-month trial in St. Louis, Missouri, involving three plaintiffs.

The trial, known as “Alessi v Monsanto”, heard claims from prosecution lawyers that the use of Roundup caused three clients to develop non-Hodgkin lymphoma, a type of cancer that develops in the lymphatic system.

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The prosecution chose three plaintiffs out of dozens of others who claim the use of glyphosate-based products caused their cancer.

Cheryl Davis, 70, of Steilacoom, Washington, used Roundup for personal purposes between 1985 and 2019. She was diagnosed with non-Hodgkin lymphoma in 2004.

The second plaintiff, 65-year-old retired US Army veteran Marty Cox, sprayed Roundup at his home in West Melbourne, Florida, for two decades. He was subsequently diagnosed with B-cell lymphoma, a subtype of non-Hodgkin’s lymphoma.

The third plaintiff, Gary Gentile, 75, used Roundup at his home in Mims, Florida, between 1992 and 2005, and was also subsequently diagnosed with B-cell lymphoma.

The lawsuit relied heavily on the International Agency for Research on Cancer’s 2015 assessment that glyphosate is “probably carcinogenic to humans”.

Bayer and leading pesticide regulators around the world continue to conclude that glyphosate is not carcinogenic and that glyphosate-based herbicides are safe when used according to the label.

The jury in the Alessi case deliberated for just a few hours before deciding in favour of Bayer.

Bayer statement

Following the verdict, Bayer issued a statement saying the jury’s verdict in its favour was consistent with the assessments of expert regulators worldwide and “overwhelming evidence” from more than 40 years of scientific studies, concluding that Roundup “can be safely used and is not carcinogenic”.

The statement added: “While we have great sympathy for the plaintiffs, the jury has weighed the evidence from both sides in this case and concluded that Roundup is not responsible for their injuries.

“We continue to stand behind the safety of Roundup and will confidently defend the safety of our product, as well as our good-faith actions in any future litigation.”

The next trial is in Wyzik in Broward County, Florida, which is due to begin on 19 September 2022.

Glyphosate is the main active ingredient in Bayer’s Roundup herbicides, which are widely used to control broad-leaved weeds and grasses in agriculture across the world.