Glyphosate in the Crosshairs

By Jeff Malone, a no-tiller from Coulee City, Wash., and President of the Washington Association of Wheat Growers
Published July 2025 on Wheat Life

Our farm started using Roundup (glyphosate) close to 40 years ago. Maybe even 50. What began as a simple weed control solution has become one of the foundational tools in modern agriculture. But today, it’s under fire like never before. As regulatory and public scrutiny intensifies, it’s time we speak plainly about how glyphosate fits into real world farming, and what’s at stake if we lose access to it.

We use glyphosate every spring. As we’ve transitioned more toward no-till and direct seeding, glyphosate use has become even more critical. We apply it on our chemfallow acres, helping manage weed pressure in a sustainable, efficient way. 

I want to be clear. We never use it on our standing wheat crop. We don’t desiccate our crop with glyphosate at harvest like you see in some other countries. We’re fortunate to have a naturally occurring harvest window; our crop finishes on its own.

When we do spray, it’s at a low rate, typically a pint per acre. That’s not much. It’s targeted, efficient and part of an integrated approach that works with our environment, not against it. And with the rise of precision tools like WEED-IT and other site-specific applicators, the technology is only getting better These tools allow us to reduce our chemical use even further. That’s good for the bottom line, and it’s good stewardship.

The push to eliminate glyphosate ignores all of that. It ignores the farmers who rely on it to maintain soil health through conservation practices. It ignores the data showing how glyphosate has enabled fewer passes with heavy equipment, reducing emissions and soil erosion. And it ignores the alternatives we’d be forced to use — chemicals like Paraquat and Gramoxone, which are far more toxic and much more hazardous to apply.

Not About Just Glyphosate

This conversation isn’t just about one product. It’s about what kind of agriculture we want to support in this country. Glyphosate has become a scapegoat in a broader campaign against modern production practices. Activists have cherry picked data, amplified worst-case scenarios, and ignored the generations of farmers who’ve safely and responsibly used this tool. 

Are there risks? Of course. That’s why we have labels and training and safety standards. But let’s not confuse precaution with prohibition. The conversation around glyphosate reflects a deeper divide between people who understand food production and those who only consume it. Many in our country have the luxury of being disconnected from the land. They don’t know what it takes to grow a healthy, affordable, and sustainable crop.

They’ve never seen the weeds explode after a wet spring. They’ve never had to budget for diesel and fertilizer and labor in a volatile market. And they’ve never watched as tools they depend on are stripped away based on misinformation.

Glyphosate is Not the Enemy

I believe this issue represents one of the greatest internal challenges American agriculture faces today: the growing gap between producers and the policies that govern them. As farmers, we’re committed to doing things right, to following the science, using the best available technology, and improving year after year. 

But that only works if we’re allowed to use the tools we need. We need to show policymakers, consumers, and even our neighbors that glyphosate is not the enemy. It’s a tool, just like a no-till drill or a crop rotation plan. When used properly, it helps us protect the soil, conserve resources, and grow the food this country relies on.

Glyphosate may be in the crosshairs, but so is the future of practical, sustainable agriculture. Let’s not lose sight of what really matters.

Read more updates on Wheat Life »

Dutch Regulator: Italian Study Claiming Glyphosate Causes Cancer is Unreliable

Published June 28, 2025 on Amsterdam's NL Times

Experts at the Dutch Board for the Authorization of Plant Protection Products and Biocides (Ctgb) say a recent Italian study linking glyphosate, an ingredient in weedkillers like Roundup, to cancer in lab animals is flawed and does not change their assessment of the substance.

According to the Ctgb, the scientific publication released earlier this month “does not lead to the conclusion that the substance glyphosate is carcinogenic.” The agency reviewed the study at the request of the Ministry of Agriculture and rejected the authors’ claim that their rat experiments provided “robust evidence” of carcinogenicity.

The Ctgb said the reliability of the research is difficult to verify because the raw data were not made available. For that reason, the agency recommended that European Union authorities responsible for pesticide and food safety request and review the complete underlying data.

The Ctgb also raised several substantive objections to how the study was conducted and presented. One major criticism was that the researchers combined different types of tumors that developed in the rats, even though those tumors originate through unrelated biological processes. “This results in higher statistical significance, but it is not biologically correct,” the agency concluded.

Another issue concerns the rats themselves. The Sprague-Dawley strain used in the experiments is known to frequently develop spontaneous tumors. “It cannot currently be said that the tumors found are a consequence of exposure to glyphosate or glyphosate-containing products,” the Ctgb said. Some tumor types appeared in only a single animal, and in other studies where rats were given higher doses of glyphosate, such tumors were not observed at all.

The agency also noted inconsistencies in the results. In some cases, a rat exposed to a low dose of glyphosate developed a tumor, while rats exposed to higher doses did not. “If glyphosate were causing tumors, it would be expected that higher dosages would lead to more or faster tumor formation,” the Dutch evaluators wrote. “Such a dose-response relationship is not seen in this study.” 

Read the original article on NL Times »

Is Roundup Messing With Our Gut Microbiome?

By Nina Elkadi
Published July 4, 2025 on Ambrook Research

When University of British Columbia professor of biochemistry and molecular biology Deanna Gibson and then-PhD candidate Jacqueline Barnett began researching glyphosate, they hoped their hypotheses would not be true.

“I hoped not to see anything because it would mean that when I banned my husband from spraying Roundup all the years that I was rearing my children, it would have been meaningless,” Gibson said. She’d long feared she would get exposed to the glyphosate in her garden, but it turns out most people are likely exposed through their food. “Because every time I gave them a piece of bread or the lentils that we eat, I unknowingly was causing them damage.”

Glyphosate, of course, is the active ingredient in Bayer-Monsanto’s infamous herbicide Roundup, a weedkiller that has changed the way farmers farm and gardeners garden. According to the Environmental Protection Agency (EPA), glyphosate “is important in the production of fruits, vegetables, nuts, and glyphosate-resistant field crops such as corn and soybeans.”

In 2015, Roundup became a more infamous name when the International Agency for Research on Cancer (IARC) declared glyphosate a “probable carcinogen” to humans. The IARC reviewed 1,000 studies on glyphosate, some of which looked at farmers exposed to the herbicide through their work.

EPA Says There’s No Danger

The EPA has maintained that glyphosate is not dangerous to humans. But further research, like the work being done by Gibson and Barnett, is expanding on what glyphosate can do to the gut. Due to the way glyphosate inhibits bacterial pathways, Barnett’s latest research concludes that mice with grandparents exposed to glyphosate develop colitis. This connection has been a burgeoning area of interest in the past few years — authors of one 2013 paper concluded that glyphosate “is the most important causal factor in [the Celiac] epidemic.” Another paper, published in 2023, argued that glyphosate “significantly impacts gut microbiota composition.”

In her latest study, Barnett consulted with a registered dietician to calculate how much glyphosate residue is in our food. That number constituted the first dose she tested on mice. The other dose was set based on the EPA’s “acceptable daily intake” of glyphosate, which the agency claims can be consumed daily without any ill effects.

“Our average American diet dose that we calculated was about 0.01 milligrams per kilogram per day, whereas the EPA currently states that you can consume 1.75 milligrams per kilograms per day. We’re talking about a 175-time difference in doses,” Barnett said. “We found that in otherwise healthy mice, whose grandparents were exposed to glyphosate at these two doses that I mentioned, offspring in the F1 and F2 generation developed colitis. We saw it in that average American diet dose. We saw it in that EPA high level dose. And so that was shocking.”

While the EPA’s numbers may seem high, people are likely exposed to glyphosate in many different ways, the most common being through the fruits, vegetables, and grains we eat. According to the Environmental Working Group (EWG), high levels of glyphosate can be found in everything from hummus to oats. It is also found in the urine of 87 percent of children tested in the United States. In some heavily farmed states, glyphosate can even be found in tap water. EWG claims that the EPA’s high limits for human consumption ultimately allow for not enough regulation, and too much glyphosate residue left in our foods.

Authors of one 2013 paper concluded that glyphosate “is the most important causal factor in [the Celiac] epidemic.”

Barnett also looked at the serum levels of different hormones and different metabolic components in the mice and noticed that these animals had a dramatic decrease in GLP-1, which stimulates insulin secretion. GLP-1 is what Ozempic, the diabetes drug now viral for its use as a weight-loss tool, activates in the body. Without it, the body cannot use sugars as fuel. In her study, exposure of generations of mice exposed to glyphosate subsequently have “very low levels of GLP-1.”

Still, not everyone is convinced that glyphosate is bad for the gut, or really, even, bad at all. In 2023, the EU Commission renewed the approval of glyphosate for 10 years, while Bayer consistently defends the product’s safety in multiple lawsuits. And some argue that the chemical’s agricultural benefits outweigh its potential harms.

“That’s just propaganda,” said Bill Freese, science director of the nonprofit advocacy group Center for Food Safety. “There’s so much propaganda out there on glyphosate.”

Freese explained that other strategies, like crop rotation, can significantly reduce the need for herbicides. Additionally, over 35 different species of weeds have developed resistance to glyphosate, so its widespread efficacy is becoming less of a reality.

In 2020, the Center for Food Safety sued the EPA over their latest approval of glyphosate, claiming that the EPA “did not adequately consider whether glyphosate causes cancer.” In 2022, the courts agreed, striking down the EPA’s human health assessment of glyphosate. Now, the group is suing the EPA again, claiming that glyphosate’s registration is illegal without a thorough safety standard.

Safety is the focus of Barnett and Gibson’s research, and, today, gut health is connected more and more with brain health. Research from Johns Hopkins, Harvard, and the Cleveland Clinic all describe how the gut can influence certain conditions like depression and anxiety. In Barnett’s research, the mice who were descendants of glyphosate-exposed grandparents did not have much interest in exploring their surroundings. Scientifically, the mice also had reductions in kynurenine — a central metabolite which regulates immune response — which helps the body and brain form new memories.

“I think it’s fair to say that there’s a scientific consensus that glyphosate is a carcinogen in particular.”

“I don’t know if there is any pesticide that’s been so heavily marketed as glyphosate as being safe, as being biodegradable, and as being safer than table salt,” Freese said. “It’s just remarkable the degree of deception in Monsanto’s ads for glyphosate.”

Regulators Vs. Scientists

It is difficult for a true “consensus” to be reached on causation when bodies are exposed to something over time. This was clear with DDT and with tobacco. As Freese noted, sometimes regulators reach different conclusions than scientists.

“I think it’s fair to say that there’s a [scientific] consensus that glyphosate is a carcinogen in particular,” Freese said, citing a paper signed by almost 100 scientists supporting this claim. “Among regulators, there’s kind of a different view that prevails. I think it’s explained by the fact that glyphosate is a really popular herbicide, and the pesticide companies and the big industrial farming groups have fought back really hard, and they influence the regulators.”

Though glyphosate was initially introduced to the masses in the 1970s, in 1996 Monsanto began selling genetically modified “Roundup Ready” crops that could withstand glyphosate. This “revolution” has resulted in glyphosate being the most commonly used herbicide of all time. Today, almost all soybeans grown in the United States are genetically modified.

Research being done on the connection between the glyphosate and the gut is still preliminary, and in a moment when microplastics, forever chemicals, and alcohol are also being investigated for messing with our guts, it is difficult to fully pin down one culprit. But Barnett believes it is already time for something to change.

“Ultimately, agricultural workers are going to continue to use it until we find something better,” Barnett said. “We need something better.” 

Read the original column on Ambrook Research »

New Study Adds to Evidence That Glyphosate Can Cause Cancer

By Carey Gillam
Published June 10, 2025 on The New Lede

A new long-term animal study of the widely used weed killer glyphosate find fresh evidence that the herbicide, introduced by Monsanto in the 1970s, causes multiple types of cancer, and may do so at doses considered safe by regulators.

The results of the two-year study, which were published June 10 in the journal Environmental Health, add to an ongoing global debate over the safety of the pesticide, which is commonly used by farmers to kill weeds in fields and pastures. The chemical is also used widely to manage weeds on golf courses, in parks and playgrounds, and in forestry management.

“Our study provides solid and independent scientific evidence of the carcinogenicity of glyphosate and glyphosate-based herbicides,” said Daniele Mandrioli, director of the Cesare Maltoni Cancer Research Center of the Ramazzini Institute in Italy. Mandrioli is the principal investigator for the study.

Weighing the Science 

Germany-based Bayer, which bought Monsanto in 2018 and inherited the glyphosate-based Roundup brand and other glyphosate-based herbicides, is currently embroiled in litigation in the United States brought by tens of thousands of people who allege that exposure to the company’s glyphosate herbicides caused them to develop non-Hodgkin lymphoma, a type of blood cancer.

One trial is underway now in Missouri, not far from Monsanto’s former headquarters. The company has already paid out billions of dollars in settlements and jury awards, and the new study comes as Bayer warns that if it cannot put an end to the litigation, it may shut down its glyphosate operations in the US, and possibly place its Monsanto businesses in bankruptcy.

Just as Monsanto always did, Bayer maintains that its glyphosate herbicides are not carcinogenic, and says the weight of scientific research backs that position.

But many studies have found cancer connections, and in 2015, the World Health Organization’s International Agency for Research on Cancer classified glyphosate as a probable human carcinogen.

Other studies have found a range of harmful effects from glyphosate exposure. A 2022 study, for example, found that glyphosate can have neurotoxic effects at doses lower than levels considered safe by regulatory agencies. And a 2023 study linked childhood exposure to glyphosate to liver inflammation and metabolic disorders.

Last month, a review of 15 years of published studies confirmed that human exposures to glyphosate herbicides have been associated with numerous adverse health outcomes that not only include cancers, liver and metabolic problems, but also reproductive and endocrine-system effects, and disruption of the microbiome, among others.

In response to the study, Bayer issued a statement accusing the Ramazzini Institute of having “a long history of making misleading claims about the safety of various products.”

“The US [Environmental Protection Agency] determined past Ramazzini studies did not meet the criteria of scientific quality for consideration in the registration review process,” Bayer said. “In addition, the EPA has retracted risk assessments that relied on Ramazzini Institute data regarding other substances and {the European Food Safety Authority] has publicly expressed its frustrations with the institute’s lack of transparency after it claimed to find adverse health effects caused by artificial sweeteners.”

Dosing Drinking Water

In the new study from Italy, the researchers looked at the impacts of glyphosate alone as well as the impacts of two types of commercial glyphosate-based formulations that are used in Europe and the United States. They administered the weed killers to rats via drinking water beginning in prenatal life, at doses of 0.5, 5, and 50 mg/kg body weight per day for two years and compared them to control groups that did not receive the pesticide doses More than 1,000 rats were part of the study.

The European Union’s acceptable daily intake for glyphosate is set at 0.5 mg/kg body weight/day, and the EU’s “no-observed adverse effect level” (NOAEL) is 50 mg/kg body weight/day. In all three treated groups, increased incidences of benign and malignant tumors were seen in multiple tissue sites compared to rats in a control group that did not receive any of the pesticide. The researchers said the study results indicate the glyphosate herbicides can cause a range of cancers, including leukemia.

“Our results indicate that, while glyphosate alone is capable of causing a number of benign and malignant tumors, [glyphosate-based herbicide] co-formulants may enhance the carcinogenicity of glyphosate, particularly in the case of leukemia,” the study states.

Most of the tumors that developed are considered rare in Sprague Dawley rats, the type used in the study, the scientists said. They noted that roughly 40% of the leukemia deaths seen in the treated groups occurred early in the animals’ lives, though increased early deaths were also seen in connection with other types of tumors. Long-term studies on rats are commonly used to predict is a substance is a human carcinogen. Cancer links to asbestos, benzene and many other substances were first detected in rodent studies.

The research is part of a “Global Glyphosate Study” led by the Cesare Maltoni Cancer Research Center of the Ramazzini Institute in Italy and involves scientists from Boston College, George Mason University, King’s College London, Icahn School of Medicine at Mount Sinai, Scientific Centre of Monaco, University of Bologna, the Institute of Agricultural Biology and Biotechnology of the Italian National Research Council the Italian National Institute of Health, and the National Food Safety Committee of the Italian Ministry of Health.

In 2022, the group published prior findings showing adverse effects of glyphosate at doses that are currently considered safe.

“The findings from this carefully conducted study, and especially the observation that prenatal exposures of infant rats to glyphosate during pregnancy increase incidence and mortality from early-life leukemia, is a powerful reminder of human infants’ great vulnerability to toxic chemicals,” Philip Landrigan, who participated in the study and directs the Program for Global Public Health and the Common Good at Boston College, said in a statement.

Read the original column on The New Lede »

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