A jury in Philadelphia concluded that Roundup is linked to a man's cancer, the plaintiff's attorneys said. (Jeff Greenberg/Universal Images Group/Getty Images)

(CNN) — A Pennsylvania jury handed down a $2.25 billion verdict against Monsanto and its parent company, Bayer, after determining its Roundup herbicide product caused a man’s cancer, the plaintiff’s lawyers announced.

John McKivison, 49, who was diagnosed with non-Hodgkin’s lymphoma, sued the company, saying he developed the cancer after using Roundup on his property for two decades, his attorneys with Kline & Specter law firm said in a news release Monday.

The jury delivered its verdict, which includes $2 billion in punitive damages, in Philadelphia Common Pleas Court on Friday after concluding Roundup “is a defective cancer-causing product, that Monsanto was negligent, and that Monsanto failed to warn about the dangers” of the weed killer, the law firm said.

“The jury’s unanimous verdict was a condemnation of 50 years of misconduct by Monsanto and a declaration that its misconduct was in reckless disregard of human safety and a substantial cause of John McKivison’s cancer,” McKivison’s attorneys, Tom Kline and Jason Itkin, said in a statement.

Bayer, which acquired agrochemical giant Monsanto in 2018, said it will appeal the verdict and believes it will be able to get the “unconstitutionally excessive damage award eliminated or reduced.”

“While we have great sympathy for the plaintiff in this case, we are confident that our products can be used safely and are not carcinogenic, consistent with the assessments of expert regulators worldwide,” the company said in a Friday statement.

Non-Hodgkin lymphoma patients started suing Monsanto by the hundreds after a 2015 World Health Organization report suggested glyphosate, the key ingredient in Roundup, might cause cancer.

The report, by WHO’s International Agency for Research on Cancer, said glyphosate is “probably carcinogenic to humans.”

But Monsanto has continued selling the herbicide. It maintains Roundup does not cause cancer and has refuted the IARC report, saying it’s greatly outnumbered by studies saying glyphosate is safe.

The US Environmental Protection Agency said in 2020 it had found “no risks of concern to human health when glyphosate is used in accordance with its current label” and that the chemical is “unlikely to be a human carcinogen.” The European Commission also determined last year that there is “no evidence to classify glyphosate as being carcinogenic.”

The American Cancer Society says the cause of most lymphomas is unknown, but non-Hodgkin lymphoma has been linked to risk factors, including exposure to certain chemicals in herbicides and insecticides. The organization noted that research to “clarify” the potential links is still ongoing.

Over the years, the Germany-based company has paid out more than $10 billion in settlements to thousands of cancer patients and their estates who have sued Monsanto, claiming Roundup causes non-Hodgkin’s lymphoma and accusing the company of failing to adequately warn consumers of the risk.

Very few of the suits over Roundup have gone to trial. In the cases of cancer patients Dewayne Johnson, Edwin Hardeman and Alva and Alberta Pilliod, jurors sided with the plaintiffs and awarded them tens of millions – and even billions – of dollars, though judges later reduced those award amounts, saying they were too excessive.

CNN’s Holly Yan and Danny Freeman contributed to this report.

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