Does Roundup cause cancer?


By Susan Crowell /

The news that a California jury agreed Aug. 10 with a claim that Monsanto’s Roundup product contributed to one man’s cancer was a verdict heard around the world.

It was the first of many pending lawsuits to go to trial, and opened the floodgates for others to proceed.

The jury in this case awarded the plaintiff $289 million in compensatory and punitive damages. Monsanto has said it will appeal the finding.

The cases ride on a 2015 statement by the International Agency for Research on Cancer, an independent agency under the World Health Organization umbrella, that glyphosate is a probable human carcinogen. Yet, the IARC finding and the agency itself has been panned by most in the scientific community.

A separate September 2015 evaluation of at least 54 studies — including those used by IARC — by the U.S. Environmental Protection Agency Health Effects Division’s Cancer Assessment Review Committee “concluded that the epidemiological studies in humans showed no association between glyphosate exposure and cancer of the following: oral cavity, esophagus, stomach, colon, rectum, colorectum, lung, pancreas, kidney, bladder, prostate, brain (gliomas), soft-tissue sarcoma, leukemia, or multiple myelomas.”

The committee also concluded there is “conflicting evidence for the association between glyphosate exposure and NHL [non-Hodgkin lymphoma]” and “epidemiologic literature to date does not support a direct causal association.”

The review committee also stated the studies that IARC cited “had deficiencies in the design and/or conduct of the studies,” and failed to include results from other studies that found negative connections. You can read the entire report from a link in my column on our website.

The IARC finding determines the potential for a compound to cause cancer, but not the likelihood in real world exposure. There’s a big difference.

There is another important distinction in the IARC’s evaluations: Their work evaluates cancer “hazards,” not “risks.”

Here’s the agency’s explanation of the difference: “A cancer ‘hazard’ is an agent that is capable of causing cancer under some circumstances while a cancer ‘risk’ is an estimate of the carcinogenic effects expected from exposure to a cancer hazard”, and the agency identifies “cancer hazards even when risks are very low at current exposure levels.”

All this can be confusing, but in a nutshell, the IARC finding is not a risk assessment. It determines the potential for a compound to cause cancer, but not the likelihood in real world exposure. There’s a big difference.

But jurors in these cases are like you and me — certainly not scientific experts. We rely on others’ interpretations of the science, and sometimes those experts are not as objective as we think.

It’s likely to be years before the issue is settled.


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  1. The problem I feel is that Monsanto only, and not the USDA or EPA or equivalent bodies internationally, carried our research on Roundup/ glyphosate sprayed crops/ food as a risk to consumption by humans, other consuming organisms and the wider environment in general. Essentially, Monsanto is not a neutral body and the continued success of Monsanto ( and now Bayer, the new owner) as a commercial company was/ is dependent on “suitable” commercial research findings carried out by the company itself. One would hope that chemicals used so widely around the globe would have the approval as safe by independent research institutes. Given the deteriorating health status of USA citizens over the last 30 years, and where there is a strong correlation between RoundUp usage and actual disease statistics, and where the product is intensively and extensively used, one would expect that caution would be the best policy. Especially so,when vast evidence was revealed in this Californian trial that Monsanto personnel themselves seemed aware of such health risks. The jury in question got a closer look at all the evidence than the public at large, so let us not rush to judgement that these people may have made a bad decision.

    There is also considerable evidence of Monsanto having a policy of resolutely vilifying any independent scientists whose research indicates that Roundup, and its associate GM crops/ seeds developed by the same company, is bad for human and consuming-organisms health. This Monsanto policy is more disquieting and indicates Monsanto is indeed trying to cover up it’s misdeeds.

  2. Years back when Roundup was first introduced, they had various “professionals” ride the media circuits touting its benefits and “harmlessness.” I recall the phrase: “Roundup is safe enough to drink!” Indeed a Monsanto lobbyist declared on video that you “could drink a whole quart of it” without harm.

    When the video host actually offered a quart of liquid Roundup to the lobbyist to drink, he refused saying: “he wasn’t crazy.”

    Anyone who has common sense can see that when there are mega-dollars to be made, the truth usually gets skewed. Like the $4.7 Billion in Roundup worldwide sales (23%) of Monsanto’s profits.

    Bayer really put its foot into this mess by acquiring Monsanto and Roundup for $66B. Bayer–I recall them hooking up in the 1930s with another German transnational corporation: I.G. Farben, called “Hell’s Cartel.” IG Farben Cartel was the most powerful German corporate cartel in the first half of the 20th century and the single largest profiteer from the Second World War. It combined with AGFA, Bayer, BASF, Cassella, Hoechst, and Kalle.

    IG Farben was the only German company in the Third Reich that ran its own concentration camp. At least 30.000 slave workers died in this camp; a lot more were deported to the gas chambers. It was no coincidence that IG Farben built their giant new plant in Auschwitz, since the workforce they used (altogether about 300.000 people) was practically for free. The Zyklon B gas, which killed millions of Jews, Gypsies and other people was produced by IG Farben´s subsidiary company Degesch. I.G. Farebn was also intimately involved with the human experimental atrocities committed by Josef Mengele at Auschwitz.

    Unethical human experiments are a major threat to vulnerable populations everywhere – including in the US where, for example, the EPA is seeking to conduct pesticide exposure experiments on children. The IG Farben culture continues to drive the chemical-pharmaceutical industry. “Profit uber alles” – that means ANYTHING goes – profit above all else.

    In Germany a growing number of people do not understand that IG Farben´s successors Bayer, BASF and Hoechst still refuse to apologize for their misdeeds.



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