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Weed Killer for Breakfast

An excerpt from Carey Gillam’s recent book Whitewash: The Story of a Weed Killer, Cancer, and the Corruption of Science

For many people, a toasted bagel topped with honey might sound like a healthy breakfast choice. Others might prefer a bowl of oatmeal, cornflakes, or a hot plate of scrambled eggs. Few would likely welcome a dose of weed killer that has been linked to cancer in their morning meal. Yet that is exactly what private laboratory tests in the United States started showing with alarming frequency in 2014: residues of the world’s most widely used herbicide were making their way into American meals.

Testing since then, by both private and public researchers, has shown glyphosate residues not only in bagels, honey, and oatmeal but also in a wide array of products that commonly line grocery store shelves, including flour, eggs, cookies, cereal and cereal bars, soy sauce, beer, and infant formula. Indeed, glyphosate residues are so pervasive that they’ve been found in human urine. Livestock are also consuming these residues in grains used to make their feed, including corn, soy, alfalfa, and wheat. Glyphosate residues have been detected in bread samples in the United Kingdom for years,1 as well as in shipments of wheat leaving the United States for overseas markets.2 “Americans are consuming glyphosate in common foods on a daily basis,” the Alliance for Natural Health said in its April 2016 report, which revealed glyphosate residues detected in eggs and coffee creamer, bagels and oatmeal.3

In January 2015, an advocacy group called GMO Free USA said tests it ordered showed that Kellogg’s Froot Loops cereal contained trace amounts of glyphosate. The group blamed Kellogg Company for “feeding children unlabeled GMOs and toxic herbicides” and called for a boycott of Kellogg.4 The group also said testing showed glyphosate in PepsiCo, Inc.’s Frito-Lay SunChips snacks. The food manufacturers responded by echoing Monsanto Company’s assurances, saying that pesticide residues in food are common and that any glyphosate residues are not at unsafe levels.

Researchers from Abraxis, LLC, a Pennsylvania-based scientific diagnostics company, worked with Boston University on their own testing and reported in 2014 that they found glyphosate residues in 41 of 69 honey samples and in 10 of 28 samples of soy sauce purchased from U.S. grocery store shelves.5

One lab, Microbe Inotech Laboratories, was used by several concerned companies and groups for early rounds of glyphosate testing, in part because it was founded by a former Monsanto microbiologist, Bruce Hemming, who had a stellar reputation. Microbe Inotech was small, but it had received government grants to conduct food microbiological research. Moreover, Hemming was a career scientist and entrepreneur as well as a former church missionary with twenty-eight grandchildren, and he had a deep passion for using his scientific skills to help people. Hemming started his lab in 1991, offering microbial and biochemical analyses to a range of companies that wanted tests run on their consumer and industrial products. He was surprised when the interest in glyphosate testing emerged in 2014 and was soon very surprised by the results found in his laboratory, which he operates a mere four miles from Monsanto’s massive corporate headquarters in a St. Louis suburb. Hemming knew from his work at Monsanto that glyphosate was not supposed to accumulate in the human body, but his lab detected glyphosate in breast milk samples and a range of other substances submitted for analysis. The shock quickly wore off as Hemming’s lab became one of only a few in the United States juggling an influx of testing requests from food companies, public and private researchers, and consumer organizations, all trying to determine how much, if any, glyphosate was present in food, water, and bodily fluids.6 Hemming’s reputation and that of his lab came under sharp criticism, however, by Monsanto and others who said the methodology and results were seriously flawed. Hemming’s lab was using a method known as an enzyme-linked immunosorbent assay (ELISA), which the lab said was validated. But critics claimed ELISA was too likely to produce false results to be considered definitive proof of anything.

Rising demand for more and better testing prompted one coalition of scientists and activists, working through what they call the Detox Project, to start offering testing in early 2016 through a laboratory at the University of California, San Francisco, that is registered with the U.S. Food and Drug Administration (FDA). The program was designed for individuals curious to learn if glyphosate is present in their bodies through urine testing, but it quickly expanded to include food product testing, using the more precise and well-regarded method known as liquid chromatography-tandem mass spectrometry (LC-MS/MS).

The Detox Project warns would-be testers that they may not like what they find. The group says this on its website:

Glyphosate is present at all levels of the food chain: in water, plants, animals, and even in humans. Every single study that has measured human contamination with glyphosate has found it. . . .

Despite claims that glyphosate has been widely studied by regulatory agencies and industry, little is known about the health effects of glyphosate-based herbicides at levels found in food or water.

In North Dakota, an agronomist at the state university, Joel Ransom, became so curious about glyphosate residue that in 2014 he ran his own tests on flour samples from the region. North Dakota grows much of America’s hard red spring wheat, a type that is considered the aristocrat of wheat and carries the highest protein content of all classes of American wheat. It is used to make some of the world’s finest yeast breads, hard rolls, and bagels. But growing the wheat and bringing a healthy crop to harvest is not always easy in a state known for cold and damp conditions. To make harvesting the crop easier, many North Dakota farmers spray their wheat crops directly with glyphosate to help dry the plants a week or so before they roll out their combines. The practice is also common in Saskatchewan, across the border in Canada. So when Ransom ran his tests on flour samples from the area, including flour from Canada, he expected to find some samples with glyphosate. He certainly did not expect all of them to have glyphosate residues. But they did. Ransom reported his findings to the Wheat Quality Council in February 2015, telling the group he was surprised by the results because it was generally believed by agricultural experts that if farmers used glyphosate as instructed, the pesticide’s residues should not persist in the grain, let alone in the flour made from it.

1. Home-Grown Cereals Authority (HGCA), “Pre-harvest Glyphosate Application to Wheat and Barley,” Information Sheet 02, Summer 2008,

2. Jason Vanfossan (USDA), e-mail to Terry Councell (FDA), August 29, 2014,

3. Alliance for Natural Health USA, “Glyphosate Levels in Breakfast Foods: What Is Safe?,” April 19, 2016,

4. GMO Free USA, “GMO Free USA Finds GMOs and Weedkiller in Kellogg’s Froot Loops,” press release, January 29, 2015,

5. Fernando Rubio, Emily Guo, and Lisa Kamp, “Survey of Glyphosate Residues in Honey, Corn and Soy Products,” Journal of Environmental & Analytical Toxicology 5 (November 19, 2014): 249, doi:10.4172/2161-0525.1000249.

6. Bruce Hemming, in conversation with the author, April 2015.

From Whitewash by Carey Gillam. Copyright © 2017 Carey Gillam. Reproduced by permission of Island Press, Washington, D.C.