In a 227-page “issue paper” compiled for a panel of experts, the EPA says its latest analysis indicates glyphosate, the most widely used weedkiller in the world, does not cause cancer. “The strongest support is for ‘not likely to be carcinogenic to humans’ at doses relevant to human health risk assessment,” says the paper in a discussion of the results of dozens of studies that it reviewed.
The EPA’s conclusion is at odds with the rating of “probably carcinogenic to humans” assigned by the International Agency for Research on Cancer in March 2015. The WHO agency ignited a global re-examination of the herbicide, made by St. Louis-based Monsanto, a pioneer in GMO crops. Monsanto created corn, soybean and cotton crops, among others, that tolerate doses of the weedkiller. Monsanto has defended the safety of its herbicide.
Critics of GMO foods used the IARC rating of glyphosate as ammunition to question the broad-scale adoption of GMO crops in the United States and challenge arguments that the crops are needed to feed the growing world population. Use of glyphosate skyrocketed following U.S. approval of Monsanto’s biotech crops two decades ago.
The European Food Safety Authority ruled last November that glyphosate was unlikely to pose a cancer risk to humans. This May, an FAO/WHO body said the weedkiller was unlikely to pose a cancer risk to humans through dietary exposure. The administrative arm of the European Union extended the EU license for glyphosate for 18 months following a repeated deadlock by EU nations in June over renewing the license.
The EPA is assessing glyphosate as part of a review, required by law every 15 years, of pesticides. Work began in 2009 and the agency now expects the review to be completed in 2017, rather than before the end of this year. The agency assembled the issue paper ahead of an Oct. 18-21 meeting of a scientific advisory committee. The proposed conclusion of the paper is “not likely to be carcinogenic to humans” but the agency said it wanted the committee’s evaluation and interpretation of the available data for each line of evidence. Glyphosate was first approved in 1974.