In a column in the New England Journal of Medicine, two scientists called for a new U.S. safety assessment of glyphosate, the most widely used herbicide in the world, said Reuters. The scientists said the new review was appropriate because of a sharp increase in use of the weedkiller on genetically engineered food crops and the determination by a WHO agency to classify glyphosate as “probably carcinogenic” to humans. The authors of the column, epidemiologist Philip Landrigan and professor Chuck Benbrook of Washington State U, said the EPA relied on outdated studies when it recently approved the weedkiller for use.
Glyphosate is the key ingredient in Roundup, a weedkiller developed by Monsanto. Regulators in many countries besides the United States consider it among the safest herbicides available. WHO’s International Agency for Research on Cancer decided on March 20 to list the weedkiller as “probably carcinogenic to humans” based on studies that show it can cause cancer in lab animals and limited evidence of carcinogenicity in humans.
IARC says its evaluates cancer hazards but not the risk associated with exposure to a substance. “Risk measures the probability that cancer will occur, taking into account the level of exposure,” it says, while an agent is considered a hazard if it is capable of causing cancer under some circumstances.