A Scientist Didn’t Disclose Important Data—and Let Everyone Believe a Popular Weedkiller Causes Cancer

A World Health Organization group called RoundUp a “probable carcinogen,” but it didn’t have all the facts.

by Kiera Butler, Mother Jones, June. 15, 2017 (excerpt)

Does a common herbicide cause cancer? Over the past several years, that question has stirred up no shortage of controversy, with international health agencies offering conflicting information. The weedkiller, a chemical called glyphosate, is commonly sold by the agribiz giant Monsanto under the brand name RoundUp. Introduced in the mid-1970s, it’s now the world’s most widely used pesticide, with some 250 million pounds sprayed on US crops annually. 

“This is a board of people whose job it is to assess evidence, so they should be able to do that before it’s published.” 

RoundUp has long been considered a benign alternative to harsher weedkillers. After extensive reviews, most regulatory agencies—the US Environmental Protection Agency, the European Food Safety Authority, and those of many other nations—have come to the conclusion that it does not cause cancer. So when the International Agency for Research on Cancer (IARC), a division of the UN’s World Health Organization, declared RoundUp a probable carcinogen in 2015, there was an international outcry. Shortly after, 184 plaintiffs in California filed a legal case against Monsanto, saying that the company failed to warn them about the risks of its product. Since then, in a separate suit, hundreds more plaintiffs have claimed that RoundUp caused their cancers, citing the IARC’s findings as evidence.

About that evidence: According to a new Reuters investigation, Aaron Blair, the scientist who led the IARC’s review panel on glyphosate, had access to data from a large study that strongly suggested that Roundup did not cause cancer after all—but he withheld that data from the RoundUp review panel. Weirder still: Blair himself was a senior researcher on that study. From the Reuters report:

Previously unreported court documents reviewed by Reuters from an ongoing US legal case against Monsanto show that Blair knew the unpublished research found no evidence of a link between glyphosate and cancer. In a sworn deposition given in March this year in connection with the case, Blair also said the data would have altered IARC’s analysis. He said it would have made it less likely that glyphosate would meet the agency’s criteria for being classed as “probably carcinogenic.”

read … Mother Jones

Reuters: Cancer agency left in the dark over glyphosate evidence 

GLP: WHO’s IARC under fire for ignoring exculpatory data on glyphosate: Should it be reformed or abolished?