Federal Jury Finds Monsanto’s Weed Killer Roundup Was A “Substantial Factor” In One Man’s Cancer– Breaking Down The New Evidence on Weed Killer and Cancer Risk

This verdict comes after another case in California in which a school groundkeeper who said Monsanto’s Roundup caused his cancer was awarded $80 million.

"We have great sympathy for Mr. Hardeman and his family, but an extensive body of science supports the conclusion that Roundup was not the cause of his cancer. Bayer stands behind these products and will vigorously defend them,” Bayer said in a statement. "We are confident the evidence in phase two will show that Monsanto's conduct has been appropriate and the company should not be liable for Mr. Hardeman's cancer."

There’s been a lot of back-and-forth over the past few years about whether Roundup causes cancer. And after a lot of speculation and confusion, at this time, scientists still can’t say for sure whether glyphosate, the main chemical in the weed killer, is a carcinogen.

A recently published meta-analysis took into account several studies that looked at glyphosate and non-Hodgkin lymphoma and showed that there was a “compelling link” between the chemical and development of the cancer. Rachel Shaffer, a study co-author and a Ph.D. student in environmental toxicology at the University of Washington, explained in a blog post that people who are highly exposed to the chemical have a roughly 2.8% chance of getting non-Hodgkin lymphoma … compared to a 2% chance for the general population. Those numbers may not seem large, but when explaining the relative risk … Shaffer said people who have been heavily exposed to glyphosate-based herbicides (like those who spray it on plants every day at work) have a 41% increased risk of developing the disease at some point in their lives, compared to people who were not highly exposed.

“Our results indicate that individuals who are highly exposed to glyphosate have an increased risk of [non-Hodgkin lymphoma], compared to the control/comparison groups,” Shaffer wrote. “This finding itself is not entirely earth-shattering: the results from prior meta-analyses were similar. But, it adds more support to the carcinogenic classification.”

So if multiple studies have suggested weed killers like Roundup aren’t safe, why hasn’t the government enforced more strict regulations on it? In general, it’s really difficult for scientists to prove that any chemical is absolutely harmful or carcinogenic. “Establishing that a given agent causes a health outcome is close to impossible,” Dr. Melissa Furlong, an environmental health expert from the University of Arizona College of Public Health, said. From an ethical standpoint, it’s hard to conduct studies on the harmful effects of a chemical without exposing people to that potential harmful chemical. And without definitive data, it’s really hard to change regulations around consumer goods.

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