Most Americans have toxic weedkiller in their urine, 'disturbing' study finds

• A popular weedkiller ingredient was found in the urine of US adults and children.
• More than 80% of urine samples tested contained glyphosate, the active ingredient in Roundup.
• The chemical may be linked to an increased risk of certain cancers, but more research is needed.

Between the myriad chemicals used to deter pests, kill weeds and fungus, and optimize crop yield, it's no surprise that some toxins end up in the food we eat.

One such controversial ingredient, a weedkiller called glyphosate, has been found in the urine of more than 80% of American research participants meant to represent the US population.

Almost a third of people studied were children between the ages of six and 18, according to a Centers for Disease Control and Prevention report published in June. The report used data from the 2013–2014 National Health and Nutrition Examination Survey and involved 2,310 people.

Farmers in the US spray more than 200 million pounds of glyphosate, sold as the weedkiller Roundup, over their fields each year, according to the public health watchdog group US Right To Know. The chemical is widely used on genetically modified crops such as corn and soybeans.

Thousands of people have sued the company that manufactures Roundup, claiming that the weedkiller causes cancer. Public health agencies have been divided on whether the chemical poses a serious health risk, but the CDC's recent finding demonstrates a need for more research.

Glyphosate is the most widely used weedkiller in history

Use of the weedkiller glyphosate has increased at least 15-fold since the 1990s, according to a 2017 study from the University of California San Diego School of Medicine.

Around that time, Monsanto Co. — the agrochemical company that created Roundup — began genetically modifying crops to resist the chemical, so farmers could spray whole fields without killing their crops.

The weedkiller is also used to dry out non-genetically engineered wheat and oats before harvest, and many farmers spray it on their fields before the growing season begins. According to The Guardian, glyphosate is considered the most widely used herbicide in history.

The World Health Organization's International Agency for Research on Cancer classified glyphosate as "probably carcinogenic to humans" in 2015. The US Environmental Protection Agency, however, says the herbicide does not pose a serious health risk.

An appellate court that heard some of the cases against Roundup recently urged the EPA to reconsider its findings.

Bayer, the German pharmaceutical company that acquired Roundup from Monsanto, has maintained that glyphosate does not pose any risks to humans. Still, the company said it would replace the active ingredient in herbicides meant for residential use beginning in 2023.