In an oral question to be debated on Tuesday 13 June with the European Commission, MEPs say that correspondence from the company, which was recently disclosed, has shed doubt on the credibility of a number of Monsanto-sponsored studies.
The International Research Agency on Cancer has reported that glyphosate could be carcinogenic, a finding which other studies contradict.
Monsanto said: "IARC’s review of glyphosate is just one example of IARC’s flawed processes and unsubstantiated conclusions, and should be disregarded by policymakers. Instead, the European Commission should listen to its own European Food Safety Authority (EFSA) and European Chemicals Agency (ECHA), which joined every other global health and regulatory body that has reviewed glyphosate in determining that glyphosate is not carcinogenic."
Meanwhile, US National Cancer Institute epidemiologist Aaron Blair, chair of the 17 specialists at the International Agency for Research on Cancer which found that glyphosate was a probable carincogenic in 2915, says important unpublished scientific data was not seen by IARC.
Reuters reports that previously unreported court documents from an ongoing US legal case against Monsanto show that Blair knew the unpublished research found no evidence of a link between glyphosate and cancer.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 its probable carcinogenic finding.
IARC'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.
Monsanto said the new 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.
A legal case against Monsanto, taking place in California, involves 184 individual plaintiffs who cite the IARC assessment and claim exposure to Round Up gave them cancer. They allege Monsanto failed to warn consumers of the risks. Monsanto denies the allegations.