by Ken Roseboro
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.
of Probable Carcinogen
Glyphosate has come under increased scrutiny in the past year.
Last year the World
Health Organization's (WHO)
cancer group, the International Agency for Research on Cancer
(IARC), 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
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
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.
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
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
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
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
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,
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
"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 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
"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
"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
realize when they buy wheat products like flour, cookies and
bread they are getting glyphosate residues in those products,"
"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
"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
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 (FDA)
recently said it would begin testing foods for glyphosate residues.
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
Sunflowers may also be
treated pre-harvest with glyphosate, according to the National
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
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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