Herbicides and Your Health

Medically Reviewed by Murtaza Cassoobhoy, MD on May 26, 2023
4 min read

Glyphosate is a popular herbicide used to kill certain plants and grasses, manage how plants grow, get crops ready for harvest, and ripen fruit.

It’s been in the news recently because of concerns about health risks.

Glyphosate is one of the world’s most common herbicides. It’s the active ingredient in popular weed-control products like Roundup, Rodeo, and Pondmaster. Many farmers use it during food production.

It’s often used on:

  • Fruit and vegetable crops
  • Glyphosate-resistant crops like canola, corn, cotton, soybeans, sugar beets, and wheat
  • Plantings, lawns, greenhouses, aquatic plants, and forest plantings

If you use a weed killer with glyphosate on your lawn or garden, you may be exposed to glyphosate by breathing it in, getting it on your skin, or getting it in your eyes. Your risk goes up if you:

  • Eat or smoke after applying it and don’t wash your hands first
  • Touch plants that are still wet from it

If you’re exposed, your eyes, skin, nose, and throat may get irritated. If you get it in your eyes, it could lead to mild irritation or a superficial corneal injury. If you swallow it, you may have increased saliva and burns and pain in your mouth and throat. It can cause nausea, vomiting, and diarrhea.

In some cases, people who intentionally swallowed products with glyphosate have died.

To lower your risk, wash your hands and take off your clothes after you handle one of these products.

You may also be exposed to glyphosate in your food.

Many farmers use glyphosate products in their fields and orchards. They spray it on crops like corn and soybeans that are genetically engineered to withstand glyphosate, also known as GMOs. They also spray it on non-GMO crops like wheat, barley, oats, and beans, to dry out the crops so they can harvest them sooner.

It gets into foods early in the food chain, before raw food is harvested and before it’s processed.

You may have heard in recent news that oat-based products like oatmeal, cereal, granola bars, and snack bars have glyphosate.

In one report from California scientists and the World Health Organization, 43 of 45 oat-based products tested had it. Popular breakfast foods like Quaker Old Fashioned Oats and Cheerios had above-average levels.

It’s also in grain and bean products like pasta, buckwheat, barley, kidney beans, and chickpeas.

Some foods may surprise you, like avocados, apples, blueberries, cherries, cucumbers, dates, dried peas, garlic, lemons, olives, peanuts, pomegranates, potatoes, rice, spinach, sugarcane, tobacco, tomatoes, and walnuts.

To limit your exposure, buy organic products. Glyphosate is banned in organic farming. But that doesn’t eliminate it entirely. In the World Health Organization report, one-third of organic oat products tested had traces of glyphosate. But they were below levels associated with risk.

It’s possible glyphosate drifts over from nearby fields with conventionally grown crops or during cross-contamination at processing facilities that handle non-organic crops.

Short-term exposure to glyphosate isn’t something you need to worry much about. Experts say it’s less toxic than table salt. But it’s long-term risk may be a concern. Scientists are divided on how much risk is involved. Reports show conflicting results. And keep in mind that most studies involve animals, not people:

  • Cancer. Some studies suggest glyphosate may be linked to cancer. Others suggest there’s no link. It’s a controversial topic. The International Agency for Research on Cancer categorizes glyphosate as a probable carcinogen for humans. In 2020, the EPA released a statement that glyphosate does not pose a risk to humans as long as it is used according to directions. They also stated that it is unlikely that it causes cancer in humans.
  • Liver and kidney damage. Glyphosate may affect your kidney and liver. Studies of dairy cows eating a diet of soybeans with high levels of glyphosate had higher risks of liver and kidney damage.
  • Reproductive and developmental issues. The EPA released a statement in 2020 that there was no evidence that glyphosate interfered with the endocrine system or hormones humans. 
  • Risk for pregnant women and children. Some scientists are concerned that pregnant women and children may have higher risks because children and developing fetuses may be more susceptible to carcinogens. But the EPA says there’s no evidence that glyphosate is a developmental or reproductive toxin, so they don't feel that they are at any higher risk.