Monsanto is in hot water as it’s facing the first of thousands of lawsuits targetting the weed-killer, Roundup. A California man suffering from terminal cancer claims the herbicide’s active ingredient, glyphosate, is responsible for his cancer. The case is going to trial, and Monsanto may end up paying billions of dollars to the plaintiff if the court finds glyphosate significantly contributed to his cancer disease.

The plaintiff, 46-year-old Dewayne Johnson, who worked as a groundskeeper, claims Monsanto failed to warn users of the carcinogenic dangers of glyphosate in Roundup. He insists the “dangerous characteristics” of glyphosate in Roundup were “substantial and contributing factors” in causing his cancer.

Roundup, Monsanto’s Flagship Product

Roundup is one of Monsanto’s biggest revenue-producing products, but it has been marred by controversy in recent years as more advocates speak out and claim it is a serious health hazard. Monsanto posted $4.8 billion in revenue for Roundup in 2015; and in its current fiscal year, the active weed-killer ingredient helped the company to post eight percent more revenue. The company was recently acquired by German chemical giant Bayer for $60 billion and is now facing lawsuits from thousands of individuals over Roundup.

Glyphosate is the cancer-causing agent in Roundup, according to Johnson and fellow advocates. Monsanto has consistently maintained that studies show glyphosate does not cause cancer.  Monsanto told CBS in a statement that they look forward to proving the safety of their product in court with Johnson, CBS News reported.

“We have empathy for anyone suffering from cancer, but the scientific evidence clearly shows that glyphosate was not the cause. We look forward to presenting this evidence to the court,” Monsanto’s statement said.

A Billion Dollar Lawsuit

Monsanto has increased advertising for Roundup to combat the recent negative press. As CBS News reported, it spent $5.6 million on Roundup campaign adverts and on promoting the safety of glyphosate in the first quarter.

“Glyphosate was a linchpin for the overall company’s profits,” said Carey Gillam, the author of “Whitewash: The Story of a Weed Killer, Cancer, and the Corruption of Science,” which examines the science and controversies about Roundup. Gillam told CBS News, “You’ve seen a really full-court press by Monsanto. You’ve seen advertising on TV about the safety of the product and a whole array of outreach efforts to promote its safety.”

Johnson is not the only individual to sue Monsanto on the relative dangers of Roundup. Thousands of others are suing Monsanto over Roundup, but Johnson’s is the first to come to court and may set a precedent for the subsequent cases. Johnson’s case comes up for hearing on Tuesday.

Apart from the fact that Monsanto and Bayer may cough up millions to Johnson if he wins in court, the publicity may affect the product’s sale worldwide, especially in Europe. European lawmakers and regulators have been looking for ways to ban the product. They cite the World Health Organization’s finding that glyphosate is “possibly carcinogenic to humans.” The EU voted by a narrow margin to continue to allow the use of Roundup last year.

Monsanto will argue studies show glyphosate is not linked to cancer. One long-term study of farmers in the U.S. found no association between glyphosate “and any solid tumors or lymphoid malignancies overall, including non-Hodgkin Lymphoma . . . and its subtypes.”

There was, however, “some evidence of increased risk of acute myeloid leukemia . . . among the highest exposed group,” but added that this association was “not statistically significant.”

“There is also certainly a great debate over whether or not science proves definitively if this causes cancer,” Gillam told CBS. When CBS asked if she uses Roundup herself, Gillam said, “I loved Roundup, years ago. I used it around my yard to kill weeds. Now, of course, I’m very nervous about using it, or any type of weed-killer.

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