Thousands of lawsuits around the nation claim glyphosate—the active ingredient in Monsanto’s popular weed killer Roundup—causes cancer. These cases are based on pretty much zero evidence, but if trial lawyers can get a jury to accept their false narrative, thousands of more cases may proceed. 

The first case to reach trial involves DeWayne Johnson, a former school groundskeeper who applied Roundup to control weeds during his employment from 2012 to 2015. Johnson was diagnosed with non-Hodgkins lymphoma in August 2014, which his case claims is a “direct and proximate result” of his exposure to Roundup. No doubt, Johnson’s cancer is truly tragic, yet it’s highly unlikely to have anything to do with glyphosate. 

Let’s look at the science. Numerous governmental bodies around the world have concluded glyphosate does not cause cancer in humans. For example, a 2016 evaluation by the World Health Organization’s Food and Agricultural Organization (FAO) notes: “[T]he only large cohort study of high quality found no evidence of an association at any exposure level.” In other words, the best quality research shows no evidence of cancer from glyphosate. 

The only “evidence” supposedly comes from rodent studies. Yet the FAO study pointed out that rat studies found no association with cancer; only mice that were administered very high doses formed tumors. Such studies reveal little if anything about risks to humans exposed to very low amounts of the chemical. Indeed, many chemicals found in a healthy diet—including those that naturally form in fruits and vegetables such as carrots, celery, and lettuce—cause tumors in rodents when administered in massive doses. These tests remind us that it’s the dose that makes the poison. 

Considering all this evidence, the FAO concluded that “glyphosate is unlikely to pose a carcinogenic risk to humans from exposure through the diet.” EPA’s 2017 draft risk assessment also concluded “glyphosate is not likely to be carcinogenic to humans,” which is the same conclusion drawn by the European Food Safety Authority in 2015.   

The lawsuits proceed only because a single research body—the International Agency for Research on Cancer (IARC)—dubbed glyphosate a “probable carcinogen” in 2015. IARC classifications are developed by ad hoc working groups that are formed periodically to review science and classify chemicals based on cancer-causing potential. Working groups might label a chemical carcinogenic or place it within one of several lower-tier categories of “probably,” “possibly,” “not classifiable”, or “probably not” carcinogenic. 

These IARC classifications are, by and large, meaningless because they only assess hazard, which is just the first step in risk assessment. A hazard assessment simply considers whether at some exposure level and under some circumstance a substance might pose a risk. The next steps consider at what doses and potency might a chemical pose risks and whether actual human exposures are significant enough to pose risks. 

During congressional hearings in early 2018, Dr. Timothy Pastoor, CEO of Pastoor Science Communications, pointed out the absurdities of IARC’s incomplete approach. Exposure is crucial to understanding risk, he explained. For example, aspirin is a valuable pain reliever at low exposures but deadly at high ones. Because IARC fails to consider potency and exposure levels, the agency ranks plutonium and salty fish in same carcinogenic category, which is clearly absurd. 

Indeed, many of IARC’s classifications are nonsensical. Consider the fact that the agency lists “smoking tobacco” in the same category with wood dust, painting houses for a living, and even eating bologna sandwiches. Yet you can’t even begin to compare the theoretical risks associated with eating bologna or working as a painter with actual smoking-related deaths that total nearly half a million annually in the United States alone. 

IARC places glyphosate in a lower-risk category of “probably” carcinogenic. Among other probable carcinogens are a wide range of industrial chemicals as well as diseases such as Malaria and the human papillomavirus type 68, and more mundane things like red meat, being a hairdresser, or “shift working” that disrupts regular sleep hours. Coffee is fine, but don’t drink it too hot, because hot beverages are also “probably carcinogenic.” 

IARC’s faulty process is compounded by the fact that its decisions appear tainted by anti-chemical ideologies and conflicts of interest. In the glyphosate case, IARC enlisted Environmental Defense Fund (EDF) activist David Poitier to help as an “advisor” on the decision. EDF is an anti-chemical activist group, which should have no influence over what is supposed to be a purely scientific evaluation. 

An exposé by blogger David Zauk revealed the fact that Poitier also had a serious financial conflict of interest. Within a week of the IARC classification, attorneys that had been developing lawsuits against Monsanto retained Poitier as an expert witness. After signing with the law firm, Poitier collected more than $160,000 for his services while trotting the globe lobbying for government bans on glyphosate, all without disclosing who compensated him. 

If that were not bad enough, Reuters’ investigative reporter Kate Kelland discovered that the IARC monograph was essentially doctored at the last minute to change the final conclusion. Kelland reported: “Reuters found 10 significant changes that were made between the draft chapter on animal studies and the published version of IARC’s glyphosate assessment. In each case, a negative conclusion about glyphosate leading to tumors was either deleted or replaced with a neutral or positive one. Reuters was unable to determine who made the changes.”           

No court of law—or anyone else for that matter—should take any IARC decision seriously. Unfortunately, trial lawyers may be even more talented than IARC in peddling self-serving false narratives. Hopefully, Monsanto will fight this to the bitter end rather than settle because one settlement will lead to more, and eventually push a valuable product out of the marketplace for no good reason.