Cancer agency left in the dark over glyphosate evidence

The World Health Organization's cancer agency says a common weedkiller is "probably carcinogenic." The scientist leading that review knew of fresh data showing no cancer link - but he never mentioned it and the agency did not take it into account.The epidemiologist from the U.S. National Cancer Institute had seen important unpublished scientific data relating directly to a key question the IARC specialists were about to consider: Whether research shows that the weedkiller glyphosate, a key ingredient in Monsanto’s best-selling RoundUp brand, causes cancer.Previously unreported court documents reviewed by Reuters from an ongoing U.S. legal case against Monsanto show that Blair knew the unpublished research found no evidence of a link between glyphosate and cancer.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.”But IARC, a semi-autonomous part of the World Health Organization, never got to consider the data. The agency’s rules on assessing substances for carcinogenicity say it can consider only published research – and this new data, which came from a large American study on which Blair was a senior researcher, had not been published.The lack of publication has sparked debate and contention. A leading U.S. epidemiologist and a leading UK statistician – both independent of Monsanto – told Reuters the data was strong and relevant and they could see no reason why it had not surfaced.Monsanto told Reuters that the fresh data on glyphosate could and should have been published in time to be considered by IARC, and that the failure to publish it undermined IARC’s classification of glyphosate. The legal case against Monsanto, taking place in California, involves 184 individual plaintiffs who cite the IARC assessment and claim exposure to RoundUp gave them cancer. They allege Monsanto failed to warn consumers of the risks. Monsanto denies the allegations.