Monsanto Co. filed suit against a California state agency Thursday to keep it from including glyphosate on a list of cancer-causing chemicals.
The California Office of Environmental Health Hazard Assessment said in September it planned to put the herbicide on its Proposition 65 list. That list, created in 1986, includes chemicals known to the state of California to cause cancer.
Glyphosate is a broad-spectrum herbicide that St. Louis-based Monsanto patented in the 1970s under the RoundUp label.
Last year the cancer research arm of the World Health Organization announced glyphosatewas probably carcinogenic to humans. The California agency pointed to that report by the International Agency for Research on Cancer, saying it had no choice but to place it on the Proposition 65 list.
Monsanto has adamantly denied that glyphosate is cancer-causing.
"Glyphosate doesn’t cause cancer, so listing glyphosate under California’s Prop 65 simply isn’t warranted scientifically and it also causes unwarranted confusion among consumers," said Sam Murphey, Monsanto’s external affairs lead on chemistry in an interview with St. Louis Public Radio on Friday.
The company points to evaluations by regulatory agencies over 40 years that have found glyphosate can be used safely. That includes the U.S. Environmental Protection Agency, the European Commission and the European Food Safety Authority Organization.
Monsanto’s suit claims that the International Agency for Research on Cancer has no regulatory role.
"The conclusion of IARC, which is based in France, is really erroneous and was really based on selectively interpreted data," Murphey said. "And IARC itself says its classification should not be the basis for any type of regulatory decision making."
Sam Delson, external affairs director for the California Office of Environmental Health Hazard Assessment, said it does meet the listing mechanism.
"We believe it meets the criteria for listing under the California Labor Code and expect to complete the listing unless there is evidence to the contrary," Delson said.
The office received nearly 9,400 comments last fall regarding the listing of glyphosate, more than they’ve ever received, according to Delson. Those comments are currently under review, he said.
If glyphosate is listed, Delson said the chemical would not be banned or necessarily restricted. He said a warning might be placed on the herbicide but a one-year grace period is given companies to meet a "safe harbor level." If the chemical can come in below a risk level of one in 100,000, the office would require no warning.
But Monsanto claims in its suit that the listing would be harmful to the company and confusing for consumers.
"Glyphosate does not cause cancer," said Murphey, "so it should not be listed, and listing could potentially have labeling implications and de-selection implications."
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