WHY FARMERS ARE USING GLYPHOSATE TO KILL THEIR CROPS — AND WHAT IT MIGHT MEAN FOR YOU
A common herbicide is ending up in our food, thanks to the growing practice of using it to dry crops in preparation for harvest.
It was the spring of 1978 and I was 7 years old when the first scoops of Ben & Jerry’s ice cream were sold in Burlington, Vermont, about an hour from the rural home I shared with my parents and infant sister. I don’t remember when I got my first taste, but it probably wasn’t long after that, and it was the beginning of a nearly four-decade love affair that continues to this day.
Two years before the first Ben & Jerry’s scoop shop opened, the U.S. food system saw another first: The introduction of the herbicide glyphosate, commonly sold under the trade name Roundup. Glyphosate was introduced in the U.K. and Malaysia in 1974, but didn’t gain regulatory approval in North America until 1976, where it quickly earned favor in the agricultural industry for its weed-killing abilities. In the mid-1990s, genetically modified, glyphosate-resistant soybeans were introduced (other crops, including corn, canola, alfalfa and sorghum soon followed), allowing for broad-spectrum applications of the herbicide throughout the growing season and resulting in a massive uptick in use that, like my fondness for premium ice cream, continues unabated.
Another use that few consumers are aware of also has contributed to increased glyphosate use: Pre-harvest crop desiccation. Originating in Scotland in the 1980s, this practice involves applying the herbicide to a standing crop toward the end of the growing season with the express purpose of expediting the natural process that would occur, where a crop slowly dies and dries in the field. The glyphosate kills the crop so it can be dry enough to harvest sooner than if it were left to die naturally — allowing the farmer to clear the field before the onset of unfavorable weather. Given how long they are usually in storage, the moisture levels of grain crops need to be low enough to store without getting moldy. The practice has since gained significant traction in North America, particularly in the northern regions of the Great Plains and the grain belt of Midwestern and western Canada, where cold, wet weather comes early.
For these farmers glyphosate-induced pre-harvest crop desiccation provides a couple other advantages. The accelerated drying process reduces potential post-harvest energy inputs, such as the need to use a grain dryer. The practice also generates a physiological “last gasp” response in less mature plants that expedites ripening and helps them “catch up” to their companions, ensuring more consistent yields. This in turn allows successive crops to be sowed earlier and improves weed control.
Currently, few statistics exist regarding the acreage subject to glyphosate desiccation or the overall quantity of glyphosate use for drying, but there’s little doubt that the practice is expanding across a variety of crops including corn, peas, soybeans, flax, rye, lentils, triticale, buckwheat, canola, millet, potatoes, sugar beets, soybeans and other edible legumes.
As a result, glyphosate has been showing up in trace amounts in food — including Ben & Jerry’s ice cream — raising red flags among consumer groups and even causing companies to change their sourcing to avoid contamination.
The exact timing of the application depends on a number of factors, but generally ranges from three to seven days before the onset of harvesting activities. And herein lies a potential explanation for the appearance of glyphosate in Ben & Jerry’s, as well as a large number of other food products. “Pre-harvest desiccation may account for only a small percentage of overall glyphosate use,” says Charles Benbrook, a visiting scholar at the Bloomberg School of Public Health who has spent more than a decade studying the use of glyphosate and associated health risks. “But it accounts for over 50 percent of dietary exposure.”
So what? That depends on whom you ask. The accepted regulatory stance is that glyphosate is relatively benign; indeed, in 2015 the U.S. Environmental Protection Agency increased threshold levels in both oats and wheat; in the case of oats, the allowable threshold for final processed grain was raised from 0.1 parts per million (ppm) to 30 ppm. For its part, Monsanto claims that glyphosate poses no health risk when used according to label instructions. And, in December 2017, the EPA released a draft human health risk assessment stating that glyphosate is not likely to be carcinogenic to humans, or present other meaningful risks, assuming the product is used according to labeling instructions — supporting Monsanto’s long-held position.
“There never has been, and still to this day there remains, not much certainty regarding the health risks associated with glyphosate.” – Charles BenbrookNot everyone agrees that glyphosate is as innocuous as its manufacturer and the EPA would have us believe, however. The World Health Organization, for one, has classified it as a possible carcinogen, as has the state of California. And although the European Union recently voted to reauthorize the use of glyphosate, license was granted for only five years, rather than the 15 years sought.
“There never has been, and still to this day there remains, not much certainty regarding the health risks associated with glyphosate,” says Benbrook.
Stephanie Seneff, a senior research scientist at the Massachusetts Institute of Technology, suspects there is a link between increased uses of glyphosate — largely via the process of pre-harvest desiccation — and celiac disease, which has increased dramatically in recent years, particularly among adolescents. “Wheat-based products are showing up with a lot of glyphosate on them, and glyphosate interferes with protein digestion,” says Seneff (celiac disease is triggered by gluten, a protein).
No matter whose version of the health impacts one believes, one thing is clear: Many consumers do not find the idea glyphosate in their food an appetizing one. To this end, Ben & Jerry’s has pledged to stop sourcing ingredients subject to glyphosate-induced pre-harvest desiccation by 2020, and also advocate for policies that would put an end to the practice.
In the meantime, I haven’t given up my beloved Ben & Jerry’s. Indeed, just last week I picked up a pint (Phish Food, if you have to know). But this time, I did something highly unusual: I ate only half.
Why Is Glyphosate Sprayed on Crops Right Before Harvest?
Glyphosate, the main ingredient in Monsanto‘s Roundup herbicide, is recognized as the world’s most widely used weed killer. What is not so well known is that farmers also use glyphosate on crops such as wheat, oats, edible beans and other crops right before harvest, raising concerns that the herbicide could get into food products.
Escalating Use of Probable Carcinogen
Glyphosate has come under increased scrutiny in the past year. Last year the World Health Organization’s cancer group, the International Agency for Research on Cancer, classified it as a probable carcinogen. The state of California has also moved to classify the herbicide as a probable carcinogen. A growing body of research is documenting health concerns of glyphosate as an endocrine disruptor and that it kills beneficial gut bacteria, damages the DNA in human embryonic, placental and umbilical cord cells and is linked to birth defects and reproductive problems in laboratory animals.
A recently published paper describes the escalating use of glyphosate: 18.9 billion pounds have been used globally since its introduction in 1974, making it the most widely and heavily applied weed-killer in the history of chemical agriculture. Significantly, 74 percent of all glyphosate sprayed on crops since the mid-1970s was applied in just the last 10 years, as cultivation of GMO corn and soybeans expanded in the U.S. and globally.
Glyphosate Used to Speed Up Wheat Harvest
Charles Benbrook, Ph.D., who published the paper on the mounting use of glyphosate, says the practice of spraying glyphosate on wheat prior to harvest, known as desiccating, began in Scotland in the 1980s.
“Farmers there often had trouble getting wheat and barley to dry evenly so they can start harvesting. So they came up with the idea to kill the crop (with glyphosate) one to two weeks before harvest to accelerate the drying down of the grain,” he said.
The pre-harvest use of glyphosate allows farmers to harvest crops as much as two weeks earlier than they normally would, an advantage in northern, colder regions.
The practice spread to wheat-growing areas of North America such as the upper Midwestern U.S. and Canadian provinces such as Saskatchewan and Manitoba.
“Desiccation is done primarily in years where conditions are wet and the crop is slow to dry down,” Joel Ransom, an agronomist at North Dakota State University, said.
Ransom says desiccating wheat with glyphosate has been a useful tool for farmers.
“It does help hasten dry down and controls grain weeds and other material that slows down the threshing practice,” he said. “It has an important role in areas where it’s wet.”
Ransom says the practice has increased in North Dakota, which is the leading wheat-producing state in the U.S., over the past 15 years due to wetter weather.
While more common in Upper Midwestern states where there is more moisture, desiccation is less likely to be done in drier wheat growing areas of Kansas, Oklahoma, Washington and Oregon.
All Conventional Farmers in Saskatchewan Desiccate Wheat
According to a wheat farmer in Saskatchewan, desiccating wheat with glyphosate is commonplace in his region. “I think every non-organic farmer in Saskatchewan uses glyphosate on most of their wheat acres every year,” the farmer speaking on condition of anonymity said.
He has concerns about the practice. “I think farmers need to realize that all of the chemicals we use are ‘bad’ to some extent,” he said. “Monsanto has done such an effective job marketing glyphosate as ‘safe’ and ‘biodegradable’ that farmers here still believe this even though such claims are false.”
The vast majority of farmers in Manitoba, Canada’s third largest wheat producing province, also use glyphosate on wheat, said Gerald Wiebe, a farmer and agricultural consultant. “I would estimate that 90 to 95 percent of wheat acres in Manitoba are sprayed pre-harvest with glyphosate; the exception would be in dry areas of the province where moisture levels at harvest time are not an issue,” he said.
“Don’t Ask, Don’t Tell” Policy
According to Tom Ehrhardt, co-owner of Minnesota-based Albert Lea Seeds, sourcing grains not desiccated with glyphosate prior to harvest is a challenge.
“I have talked with millers of conventionally produced grain and they all agree it’s very difficult to source oats, wheat, flax and triticale, which have not been sprayed with glyphosate prior to harvest,” he said. “It’s a ‘don’t ask, don’t tell policy’ in the industry.”
Ehrhardt also says that crops grown to produce seed are not usually sprayed with glyphosate prior to harvest because this can damage seed germination.
Grain Millers, which has grain processing facilities in the U.S. and Canada, announced last year that it would not buy oats from Canada that had been desiccated with glyphosate. The company’s Canadian procurement manager, Terry Tyson, told Western Producer that glyphosate disrupts the natural maturing process and starch development, resulting in lower quality flakes and flour. He said the decision had nothing to do with health or safety concerns.
“Would Rather Not Eat a Loaf of Bread With Glyphosate In It”
Still, there are obvious concerns about glyphosate getting into food products.
“We are told these (glyphosate residues) are too small to matter but can we believe that?” the Saskatchewan farmer asked. “I think everyone, even farmers that use and love glyphosate, would rather not eat a loaf of bread with glyphosate in it.”
Wiebe shares similar concerns. “Consumers don’t realize when they buy wheat products like flour, cookies and bread they are getting glyphosate residues in those products,” he said. “It’s barbaric to put glyphosate in food a few days before you harvest it.”
Wiebe believes the use of glyphosate on wheat may be connected to the rise in celiac disease. “We’ve seen an explosion of gluten intolerance,” he said. “What’s really going on?”
“Can you imagine the public’s response if they knew that glyphosate is being sprayed on the oats in their Cheerios only weeks before it is manufactured?” Ehrhardt asked.
Residues of glyphosate have been found in wheat flour. Last year, Ransom reported to the U.S. Wheat Quality Council that tests on flour samples from the U.S. and Canada found that all had traces of glyphosate. However, Ransom said these were well below the maximum residue limits for glyphosate in wheat, which are 30 parts per million in the U.S.
Still, Ransom said: “I wouldn’t be surprised if someone repeated the test and found traces also.”
In response to mounting concerns over the escalating use of glyphosate, the U.S. Food and Drug Administration recently said it would begin testing foods for glyphosate residues.
Powerful Effect on Food System
Along with wheat and oats, glyphosate is used to desiccate a wide range of other crops including lentils, peas, non-GMO soybeans, corn, flax, rye, triticale, buckwheat, millet, canola, sugar beets and potatoes. Sunflowers may also be treated pre-harvest with glyphosate, according to the National Sunflower Association.
Benbrook says that a large portion of edible beans grown in Washington and Idaho are desiccated with glyphosate.
There are no statistics kept on the number of acres of wheat or other crops that are desiccated with glyphosate, according to Ransom.
While the pre-harvest use of glyphosate may account for a small amount of overall use of the herbicide, Benbrook says this still has a huge impact. “It may be two percent of agriculture use, but well over 50 percent of dietary exposure,” he said.
Further, he said: “I don’t understand why Monsanto and the food industry don’t voluntarily end this practice. They know it contributes to high dietary exposure (of glyphosate).”
Wiebe sees the situation in dire terms. “The most tragic thing is that industry is encouraging the use of glyphosate on wheat, farmers are using it, consumers are unaware of it and it’s having a powerful effect on the food system,” he said.
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The latest study to look at the long-term effects of Roundup, a popular weed killer developed by Monsanto in the 1970s, raises questions about the herbicide’s possible contributions to poor health in certain communities.
The study, published Tuesday in JAMA, tracked people over the age of 50 in southern California from 1993-1996 to 2014-2016, with researchers periodically collecting urine samples during that time.
Researchers led by Paul Mills, professor of family medicine and public health at the University of California San Diego, found that the percentage of people who tested positive for a chemical called glyphosate, which is the active ingredient in the herbicide Roundup, shot up by 500% in that time period. The levels of glyphosate also spiked by 1208% during that time.
Exactly what that means for human health isn’t quite clear yet. There are few studies of the chemical and its effects on people, although animal studies raise some concerns. One trial from the UK, in which rats were fed low levels of glyphosate throughout their lives, found that the chemical contributed to a higher risk of nonalcoholic fatty liver disease, a condition in which fat accumulates in the liver and contributes to inflammation and scarring of the tissue. Mills says that the levels of glyphosate documented in the people in his study were 100-fold greater than those in the rats.
To follow up on these results, Mills plans to measure factors that track liver disease, to see if the levels of glyphosate he found are actually associated with a greater risk of liver problems in people. He heads the Herbicide Awareness & Research Project at UCSD, an ongoing research project in which he invites people to provide urine samples to test glyphosate levels. By gathering more information about people’s exposure, he is planning to tease apart how much of it comes from actually ingesting products sprayed with the chemical, and how much can be attributed to breathing in particles that have been sprayed into the air, especially in farm communities.
Read more: Here’s Which Produce Has the Most Pesticides
In a statement, a Monsanto representative said: “The amounts reported are consistent with prior reports from the U.S. and Europe and do not raise health concerns. Since food is often grown using pesticides, trace amounts can sometimes be found in people’s urine, which is one way our bodies get rid of non-essential substances.”