Key takeaways
- Glyphosate is the active ingredient in many weed killers, including Roundup products used on farms. Farmers spray it on fields and, for some grains and beans, shortly before harvest.
- The EPA says glyphosate is “not likely to be carcinogenic to humans” at expected exposures. The World Health Organization’s cancer agency calls it “probably carcinogenic.” The EPA expects an updated review in late 2026.
- The CDC found glyphosate in more than 80% of Americans tested in 2013–2014. Average urine levels fell 38% between 2013 and 2018.
- An organic diet may lower exposure. In one small study, glyphosate in urine fell about 70% within a week of switching to organic food.
What glyphosate is and how it gets into food
Glyphosate is a weed killer. It’s the active ingredient in many herbicides, including Roundup products used on farms. Plants absorb it through their leaves, and it stops an enzyme they need to grow.
It ends up in food in two main ways:
- Weed control on crops bred to tolerate it. Many corn, soybean, canola, cotton and sugar beet crops in the U.S. are grown from seeds made to survive glyphosate, so farmers can spray the whole field.
- Spraying just before harvest. Some farmers spray grains and beans, such as oats, wheat, barley, lentils and chickpeas, shortly before harvest. It kills weeds and dries the crop evenly. Because it happens close to harvest, it can leave more residue on the grain.[10]
Which foods tend to have glyphosate
Often higher: grains and beans sprayed before harvest
- Oats and oat cereals
- Wheat and whole-wheat products
- Barley
- Lentils
- Chickpeas
- Dried peas and beans
Usually lower
- Most fresh fruits and vegetables
- Meat, eggs and dairy
- Certified organic grains and beans
The EPA sets a legal limit, called a tolerance, for each crop. For oats and wheat grain it’s 30 parts per million, which is 30,000 parts per billion.[6][10] Food above its tolerance can be seized. The EPA says federal testing hasn’t found residues above the limits, and most are well below them.[1]
Some groups argue the limits are too high. The Environmental Working Group, for example, uses its own much lower benchmark for children of 160 parts per billion.[7] Our guide to glyphosate-free oats covers those tests.
Is glyphosate safe? Where experts disagree
Two respected bodies have looked at the same chemical and come to different conclusions:
| Who | Conclusion | What they looked at |
|---|---|---|
| IARC (World Health Organization), 2015 | “Probably carcinogenic to humans” (Group 2A) | Hazard: whether it can cause cancer at some level of exposure. It doesn’t estimate the risk from the amounts in food. |
| U.S. EPA, 2017 and 2020 | “Not likely to be carcinogenic to humans” | Risk: whether it is likely to cause cancer at the amounts people are actually exposed to. |
The difference is partly about the question. IARC asks whether something can cause cancer at all. The EPA asks how likely harm is at real-world exposure levels.
The EPA’s review has also been in flux:[1]
- In June 2022, a federal appeals court set aside the human health part of the EPA’s 2020 interim decision.
- That September, the EPA withdrew the decision. It says its scientific findings still stand.
- The EPA is updating its cancer review and expects a new human health risk assessment in late 2026.
In Europe, regulators renewed glyphosate’s approval in 2023 for 10 years, with restrictions. One of them bans spraying it to dry crops before harvest.[8]
Glyphosate in the news in 2026
In February 2026, President Trump signed an executive order that treats glyphosate and elemental phosphorus as critical supplies under the Defense Production Act, to protect U.S. production.[5] The order is about supply. It doesn’t change the EPA’s limits on residues in food, and it drew criticism from some “Make America Healthy Again” supporters.[5]
How to eat less glyphosate
- Buy organic oats, wheat products and beans when you can. Organic farming doesn’t allow synthetic weed killers like glyphosate, though traces can still drift in.
- Look for “Glyphosate Residue Free” certification on oats and grain products. It means testing found none above the lab’s detection limit, usually 10 parts per billion. That’s very low, though not proof of zero.[9]
- Rotate your grains and legumes so no single food is your main source.
- Keep eating whole grains and beans. Their fiber and nutrients matter. Choose cleaner versions rather than cutting them out.
Does going organic make a difference? In a 2020 study of four families, average glyphosate in urine dropped about 71% within six days of switching to an organic diet.[3] The study was small, was funded by an advocacy group and didn’t measure health effects, but it suggests organic food lowers exposure.
Questions people ask
- What foods have the most glyphosate?
- Residues have been found in grains and beans, including oats, wheat, lentils and chickpeas, which are sometimes sprayed shortly before harvest. Independent tests have found glyphosate in most conventional oat products sampled. Levels vary with farming practice, processing and batch.
- Does organic food have glyphosate?
- Organic farming does not allow synthetic weed killers like glyphosate, so organic food usually has far less. Small traces can still show up from spray drift or shared processing equipment.
- Does washing remove glyphosate?
- Not reliably. Plants absorb glyphosate, so it is inside the grain or bean rather than only on the surface. Choosing organic or certified residue-free products is a more dependable way to eat less of it.
- What is the legal limit for glyphosate in food?
- The EPA sets a tolerance for each crop. For oats and wheat grain it is 30 parts per million. Food with residues above its tolerance can be seized.
- Is glyphosate banned in the United States?
- No. Glyphosate is approved for use in the U.S., and the EPA is updating its human health review, with a new assessment expected in late 2026.
Sources
- [1]U.S. Environmental Protection Agency. Glyphosate. accessed October 2026.
- [2]International Agency for Research on Cancer. IARC Monographs Volume 112: Some organophosphate insecticides and herbicides. 2017 (evaluated March 2015).
- [3]Fagan J, et al. Environmental Research. Organic diet intervention significantly reduces urinary glyphosate levels in U.S. children and adults. 2020.
- [4]Centers for Disease Control and Prevention. Exposure to glyphosate in the United States: Data from the 2013–2014 National Health and Nutrition Examination Survey. accessed October 2026.
- [5]Farm Policy News, University of Illinois. Trump signs order protecting glyphosate, phosphorus production. February 2026.
- [6]Electronic Code of Federal Regulations. 40 CFR 180.364: Glyphosate; tolerances for residues. accessed October 2026.
- [7]Environmental Working Group. Roundup for breakfast, part 2: In new tests, weed killer found in all kids’ cereals sampled. October 2018.
- [8]European Commission. Glyphosate: renewal of approval. November 2023.
- [9]The Detox Project. Glyphosate Residue Free certification. accessed October 2026.
- [10]Oklahoma State University Extension. Glyphosate use as a pre-harvest treatment: Not a risk to food safety. accessed October 2026.
- [11]Centers for Disease Control and Prevention. Temporal trends of exposure to the herbicide glyphosate in the United States (2013–2018). 2024.
This article is for general information. It is not medical advice and does not replace a doctor, dietitian or pediatrician. Purus gives estimates for general information; it is not a medical device and does not diagnose, treat or prevent any condition.
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