Fears Over Roundup Herbicide Residues Prompt Private Testing

U.S. consumer groups, scientists and food companies are testing substances ranging from breakfast cereal to breast milk for residues of the world’s most widely used herbicide on rising concerns over its possible links to disease.

The focus is on glyphosate, the active ingredient in Roundup. Testing has increased in the last two years, but scientists say requests spiked after a World Health Organization research unit said last month it was classifying glyphosate as “probably carcinogenic to humans.”

“The requests keep coming in,” said Ben Winkler, laboratory manager at Microbe Inotech Laboratories in St. Louis. The commercial lab has received three to four requests a week to test foods and other substances for glyphosate residues. In prior years, it received only three to four requests annually, according to its records.

“Some people want to stay out in front of this. Nobody knows what it means yet, but a lot of people are testing,” said Winkler.