Researchers have found a chemical linked to cancer, also the main ingredient in the world’s most popular weedkiller, in more than 80% of Americans, according to a Centers for Disease Control and Prevention study.

The CDC’s National Health and Nutrition Examination Survey tested nationwide urine samples stored between 2013 and 2014, finding glyphosate in 1,885 out of 2,310 samples.

Glyphosate is the main ingredient in Roundup, the world’s best-selling weedkiller. Researchers have found that exposure to glyphosate increases the risk of non-Hodgkin lymphoma, which affects the body’s lymphatic system, by 41%.

But despite the research, the U.S. Environmental Protection Agency determined during the Trump administration that glyphosate is “unlikely to be a human carcinogen” and approved its use in Jan. 2020.

In June, a federal court ordered the EPA to vacate the human health finding of the decision, citing “serious” errors in assessing human health risks from the chemical. The court also ordered the EPA to perform additional studies on the glyphosate’s effect on human health and the environment and allowed the agency to reconsider its decision on glyphosate. The EPA is expected to conclude its new review by Oct. 1.

The Monsanto Co. and its parent company, Bayer AG, have spent billions of dollars settling tens of thousands of lawsuits.

Bayer AG has reached an $11 billion agreement to settle about 80% of the lawsuits against the company. The company unsuccessfully attempted to get the U.S. Supreme Court to reject several multi-million dollar lawsuits, including one brought by a California couple diagnosed with non-Hodgkin lymphoma that was awarded $2 billion by a jury. The award was reduced to $87 million on appeal.