Dr. Kurt Straif, a section head with the World Health Organization’s International Agency for Research on Cancer (IARC), appeared in an interview with euronews defending the agency’s assessment that glyphosate probably causes cancer in humans.
“Our evaluation was a review of all the published scientific literature on glyphosate and this was done by the world’s best experts on the topic that in addition don’t have any conflicts of interest that could bias their assessment,” Straif said.
“They concluded that, yes, glyphosate is probably carcinogenic to humans based on three strings of evidence, that is clear evidence of cancer in experimental animals, limited evidence for cancer for humans from real-world exposures, of exposed farmers, and also strong evidence that it can damage the genes from any kind of other toxicological studies.”
In March 2015, the IARC concluded that glyphosate is a “probable human carcinogen,” touching off an international row on the health and safety of the widely applied herbicide. However, this past May, the United Nation’s Food and Agriculture Organization (FAO) and a different regulatory body from the WHO issued a joint report concluding that the ingredient is “unlikely to pose a carcinogenic risk to humans from exposure through the diet.”
During the euronews interview, Straif explained why the conclusions from the IARC and the FAO/WHO about the weedkiller seem to be contradictory.
“Our classification of the cancer hazards of glyphosate still stand,” he said. “We are the authority to classify cancer substances worldwide for the WHO, and it was then this other panel that looked at a very narrow angle of exposure from daily food, and then came up with the conclusion on how much of that may be safe or not.”
Basically, the IARC assessment focussed on “hazard” while the other looked at “risk.” David Eastmond, a toxicologist at the University of California, Riverside, explained to Wired how the terms are different: “If you have people gawking at sharks swimming around a tank in an aquarium, the sharks are a hazard, but they pose little risk. If you have a surfer on the beach with a shark, now that shark is both a hazard and a risk.”
During the interview, the euronews host asked Straif which body of the WHO she should trust as a “consumer, as a farmer, as an occasional beer drinker, as somebody who likes to sit in parks that have been treated with glyphosate.”
He replied, “I think it’s important to understand the literature that our assessment that glyphosate can cause cancer in humans still stands, and then you have to look at the other assessments for the specific scenarios, and that is not my authority to comment on these evaluations.”
Straif also hinted at possible conflicts of interest from the FAO/WHO report. When the euronews host asked the senior scientist if he was “disturbed” by credible reports of the FAO/WHO scientists allegedly receiving payoffs by Monsanto for a favorable glyphosate review, Straif replied, “It is an important topic that needs important scrutiny, yes.”