A state environmental agency in California says it intends to list glyphosate, the most widely used weedkiller in the world, “as known to the state to cause cancer” under the so-called Proposition 65 law. Passed in 1986 during a referendum to address concern about exposure to toxic chemicals, Prop 65 requires the state to publish annually a list of substances known to cause cancer, birth defects or other reproductive harm. The state Office of Environmental Health Hazard Assessment also proposed listing three other pesticides – parathion, malathion and tetrachlorvinphos – along with glyphosate, best known under the brand name Roundup.
The state action follows a decision by a WHO agency earlier this year that glyphosate and malathion are “probably carcinogenic to humans,” while parathion and tetrachlorvinphos are “possibly carcinogenic to humans.” The California agency said it would accept public comments until Oct. 5.
Companies have up to a year to comply with labeling requirements under Prop 65, said the Columbus (Ohio) Dispatch. It quoted a spokeswoman for Monsanto, which owns the brand name and has genetically engineered corn and soybean varieties to tolerate the weedkiller, as saying, “No regulatory agency in the world considers glyphosate to be a carcinogen.” Monsanto disputes the decision by the WHO agency.