University specialist: Glyphosate link to cancer unfounded

While glyphosate has lower toxicity than many pesticides — it's rated zero risk for homeowner use — the news and social media are laden with its purported health risks to humans, especially cancer.But those claims are out of step with scientific risk assessments related to exposure, Ronda Hirnyck, University of Idaho pesticide coordinator, said during a pesticide seminar at this year’s Agri-Action.Part of the issue with glyphosate or Roundup —a Monsanto product used to treat weeds in some GMO crops — is that everybody’s heard about it. And there are a lot of people who don’t like GMOs or Monsanto, she said.Glyphosate binds tightly to soil, and it’s not volatile in the environment. It doesn’t percolate soil to get into groundwater. It inhibits an enzyme that builds proteins a plant needs, and animals and humans don’t produce that enzyme, she said.Studies have shown there’s little to no absorption through the skin, no inhalation risk and no neurotoxicity, she said.Studies in animals and extrapolated to humans show very, very low toxicity to either, she said. The level of acute oral toxicity in mice is 10,000 parts per million. In rabbits, the only animal to show any reaction, that level was 2,000 ppm, she said.