WHO: Long-cleared Roundup ingredient ‘probably’ causes cancer

Health officials are raising new concerns about the most widely used herbicide in the world.

Earlier this month, the World Health Organization’s International Agency for Research on Cancer announced findings that glyphosate, the main ingredient in Monsanto’s RoundUp line of pesticides, is “probably carcinogenic to humans.” The research, published in The Lancet Oncology, relies on studies conducted on the chemical over the last few decades.

Use of glyphosate – which the EPA has deemed safe — has soared in the last two decades with the introduction of crops genetically engineered to withstand the herbicide. Glyphosate is also a main ingredient in a new product called “Enlist Duo” recently introduced by Dow Chemical.

Monsanto vice president of global regulatory affairs Philip Miller told Reuters that the company questioned the “quality of the assessment.”

As NewsHour reported last fall, widespread use of the chemical has also come under fire because weeds are becoming increasingly resistant to it. Dow has marketed its new product, a mix of glyphosate and the herbicide 2,4-D, as a new tool for farmers battling herbicide-resistant weeds.

But agriculture experts say farmers should look at other ways to manage weeds, like cover-cropping, increased rotation and mechanical removal.

This week, environmental groups sent a letter to the EPA renewing their calls for the agency to reconsider its decision to approve Enlist Duo. The groups also called on the EPA to reexamine its findings that glyphosate is safe.

Monsanto has come out swinging. In a press release, Chief Technology Officer Dr. Robb Fraley said the company is “outraged” and, “This conclusion is inconsistent with the decades of ongoing comprehensive safety reviews by the leading regulatory authorities around the world that have concluded that all labeled uses of glyphosate are safe for human health.”

Monsanto has demanded a retraction of the report has asked to meet with the WHO about its evaluation, Reuters reported.

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