The current scientific consensus on glyphosate

The answer depends on which health authority you ask, and that disagreement matters. The U.S. Environmental Protection Agency (EPA) and the European Food Safety Authority (EFSA) have concluded that glyphosate is not likely to cause cancer in humans at the levels people are exposed to through food and herbicide use. The International Agency for Research on Cancer (IARC), which is part of the World Health Organization, classified glyphosate as "probably carcinogenic to humans" in 2015 based on evidence in animals and limited evidence in people. These are not minor differences in interpretation—they reflect genuinely different readings of the same research.

The disagreement is not new, and it is not settled. Since the IARC classification, thousands of people in the United States have filed lawsuits against Monsanto (now owned by Bayer), the company that makes Roundup, claiming that glyphosate exposure caused their non-Hodgkin's lymphoma. Some juries have ruled in favor of plaintiffs; others have not. Regulatory agencies have not changed their positions. Understanding what each side actually says—rather than what headlines claim—is the only way to make sense of your own exposure risk.

Key Takeaways

  • The EPA and EFSA say glyphosate is not likely to cause cancer at typical exposure levels, while the IARC classified it as probably carcinogenic based on animal and limited human evidence.
  • Glyphosate is the active ingredient in Roundup and many other herbicides, and it is used on crops, in yards, and along roadsides across North America.
  • The evidence linking glyphosate to non-Hodgkin's lymphoma in humans is limited and contested; most studies in people have not found a clear connection at occupational or dietary exposure levels.
  • Your actual exposure depends on your job, where you live, what you eat, and whether you use herbicides at home—not everyone has the same risk.
  • If you have been exposed to glyphosate and have concerns about cancer risk, a conversation with your doctor about your specific exposure history is more useful than a general answer.

How the research on glyphosate splits between agencies

The EPA's most recent review, completed in 2020, looked at studies in animals, studies in human cells, and epidemiological studies (which track cancer rates in groups of people). The EPA concluded that glyphosate does not meet the criteria for classification as a carcinogen. The EFSA reached the same conclusion in its 2022 review. Both agencies acknowledged that some animal studies showed cancer at very high doses, but they determined that the doses used in those studies were far higher than any human exposure.

The IARC, by contrast, classified glyphosate as "probably carcinogenic" (Group 2A) in 2015. The IARC based this on evidence that glyphosate caused cancer in laboratory animals, evidence of DNA damage in human cells exposed to glyphosate in the lab, and what it called "limited evidence" of cancer in humans. The IARC did not say glyphosate definitely causes cancer or that it causes cancer at low doses—only that the evidence suggested it probably could. The IARC also noted that occupational exposure (farm workers, pesticide applicators) carried higher risk than dietary exposure.

These different conclusions stem partly from different standards. The EPA and EFSA focus on whether a substance causes cancer at real-world exposure levels. The IARC focuses on whether a substance can cause cancer under any circumstances, including high doses. Neither approach is wrong; they answer different questions. But they produce different answers to the question most people actually ask: "Will this hurt me?"

What the human evidence actually shows

The hardest part of this question is that direct evidence in humans is scarce. Researchers cannot deliberately expose people to a chemical and watch whether they develop cancer—so they rely on studies of people who were already exposed, either through their jobs or their diet. Those studies have produced mixed results.

The largest study to date is the Agricultural Health Study, which has tracked more than 50,000 pesticide applicators and farmers in Iowa and North Carolina since 1993. This study found no overall increase in cancer among people who used glyphosate, though some analyses suggested a possible link to non-Hodgkin's lymphoma in the highest-exposure group. Other occupational studies have found no link or only weak links. Studies of people who ate food with glyphosate residues have generally not found increased cancer risk.

The lawsuits against Monsanto have centered on non-Hodgkin's lymphoma, a blood cancer. Some juries found that glyphosate more likely than not caused the plaintiff's cancer; others found it did not. These cases do not prove causation—a jury verdict is not the same as scientific evidence—but they do show that some people who used glyphosate and developed this cancer believe the two are connected. Whether that belief is correct remains scientifically unclear.

Who is actually exposed to glyphosate

Glyphosate is not a single product—it is an active ingredient in hundreds of herbicides sold under different brand names, with Roundup being the most common. Exposure happens in several ways. Farm workers and agricultural pesticide applicators have the highest occupational exposure. People who use herbicides in their yards or gardens have lower but measurable exposure. The general population is exposed through residues in food, particularly in crops like wheat, oats, and soybeans that are sprayed with glyphosate before harvest.

Glyphosate has been detected in the urine of a large percentage of the U.S. population, which means most people have some exposure. The question is whether that exposure is at a level that poses a cancer risk. The EPA and EFSA say no; the IARC says the evidence suggests it might, especially at higher occupational levels. Your own risk depends on your specific exposure—a farm worker who applies glyphosate daily has a different exposure profile than someone who eats conventional wheat.

What happens if you have been exposed

If you have used glyphosate-based herbicides regularly or worked in an environment where you were exposed, and you are now concerned about cancer risk, the first step is to talk with your doctor. Bring information about how long you were exposed, how often, and in what context (occupational, home use, or both). Your doctor can assess your individual risk based on your exposure history and your personal and family cancer history.

You do not need to wait for a definitive scientific answer to take this step. Your doctor can discuss screening options, what symptoms to watch for, and whether your exposure history warrants any particular monitoring. They can also help you understand the difference between increased risk and certain harm—glyphosate exposure does not mean you will develop cancer, even if a link exists.

If you have already been diagnosed with non-Hodgkin's lymphoma and had significant glyphosate exposure, your doctor should know about that exposure as part of your medical history. It may not change your treatment, but it is relevant information.

How to reduce your own glyphosate exposure

If you use herbicides at home, you can reduce exposure by wearing gloves and long sleeves during application, washing your hands and clothes afterward, and following label instructions. You can also consider alternatives: hand-pulling weeds, mulching, or using herbicides with different active ingredients. If you work with glyphosate occupationally, your employer is required by law to provide safety equipment and training; make sure you are using it.

For dietary exposure, washing produce reduces but does not eliminate residues. Choosing organic produce for crops that typically have higher glyphosate residues (wheat, oats, chickpeas) is one option, though it is more expensive. The residue levels in conventional food are within the limits set by the EPA and EFSA, which both maintain that these levels are safe. Whether you believe that assessment is a personal decision based on how much weight you give to the EPA and EFSA versus the IARC.

Frequently Asked Questions

Does glyphosate cause cancer or not?

The EPA and EFSA say no; the IARC says probably. The human evidence is limited and mixed. No major health authority has concluded that glyphosate definitely causes cancer at typical exposure levels, but the IARC's classification means the question is not closed. Your risk depends on how much you have been exposed.

Is Roundup safer than other herbicides?

Roundup's active ingredient is glyphosate. Other herbicides have different active ingredients and different safety profiles. Whether one is "safer" depends on the specific chemical, the dose, and the type of exposure. Your doctor or a poison control center can compare specific products if you are concerned about a particular exposure.

Should I stop eating food with glyphosate residues?

That is a personal choice. The EPA and EFSA say residue levels in food are safe; the IARC's classification suggests caution, especially for occupational exposure. If you want to reduce dietary glyphosate, organic produce is one option. The overall health benefits of eating more vegetables—organic or conventional—likely outweigh the risk from glyphosate residues.

If I developed cancer after glyphosate exposure, does that mean glyphosate caused it?

Not necessarily. Many cancers have multiple causes, and most people exposed to glyphosate do not develop cancer. A temporal connection (exposure came before cancer) is not the same as causation. A doctor can help you understand whether your exposure history is relevant to your specific diagnosis.

Where can I find my glyphosate exposure level?

If you have occupational exposure, your employer should have records of what you were exposed to and when. For dietary exposure, the EPA publishes data on glyphosate residues in food crops. You cannot easily measure your own exposure at home, but your doctor can discuss whether testing would be useful in your situation.