EPA finds glyphosate is not a carcinogen

An Environmental Protection Agency (EPA) review panel has concluded that glyphosate, a widely used herbicide manufactured by Monsanto, likely does not cause cancer.

The EPA's Cancer Assessment Review Committee (CARC) came to the conclusion following an in-depth analysis of several dozen published and unpublished scientific studies of the weed killer. The report completed last October was inadvertently released to the public in April.

According to the report, “the epidemiological studies in humans showed no association between glyphosate exposure and cancer of the following: oral cavity, esophagus, stomach, colon, rectum, colorectum, lung, pancreas, kidney, bladder, prostate, brain (gliomas), soft-tissue sarcoma, leukemia, or multiple myelomas.”

The CARC’s report contradicts findings by the World Health Organization's International Agency for Research on Cancer (IARC) in 2015, indicating that the chemical is “probably carcinogenic to humans.”

In disputing the IARC’s findings, the EPA noted that the studies IARC included in its review had significant limitations.

“IARC’s conclusion was based on epidemiologic studies available in the open literature and carcinogenicity studies in rats (4 studies) and mice (2 studies) by dietary administration," the report stated. "Of these six studies reviewed by IARC, two studies in rats and one study in mice were previously not available to OPP (Office of Pesticide Programs). The conclusion by IARC and the additional studies not available to OPP, prompted the agency to re-evaluate the carcinogenic potential of glyphosate."

The IARC’s report had a negative impact on the agricultural chemical industry, resulting in a mandate by California to have all products containing glyphosate to be listed as carcinogenic, which Monsanto is challenging in court. The report has also led to a slew of product liability lawsuits against Monsanto by plaintiffs claiming that exposure to the company's pesticide caused their illnesses.

Monsanto introduced glyphosate to market in 1974 under the trade name Roundup. The popularity of glyphosate grew rapidly among farmers after Monsanto introduced glyphosate-resistant Roundup Ready crops, which gave farmers the ability to kill weeds without killing their crops. By 2007, glyphosate had become the most used herbicide in agriculture in the country.

Monsanto praised the EPA’s conclusion in a statement to Bloomberg BNA, and said the findings reinforce the position world pesticide regulators have taken on glyphosate: that it is not carcinogenic.

CARC’s findings are part of a review program of the environmental and overall health effects of pesticides. The program reviews every pesticide chemical once every 15 years.