(WFLA) – A leading research group claims harmful levels of a weed killer linked to cancer are showing up in foods and cereals marketed to children.

An analysis by the non-profit Environmental Working Group (EWG) found trace amounts of glyphosate in a number of products including Cheerios and Quaker Oats granola bars.

Scientists tested 29 products and found that almost three-quarters of the samples they tested contained higher levels of glyphosate than deemed safe, according to the report. 

“That does not mean, ‘Stop eating this bowl of Cheerios right now!’ But then when you think about how people eat these oats,” Olga Naidenko, senior science adviser at EWG told Mother Jones. “That’s when those numbers start to come into concern.”

Glyphosate, the active ingredient in Monsanto’s Roundup, is the most widely used herbicide in the country due to the widespread adoption of GMOs. According to the IARC, the herbicide has additional chemical ingredients that are “probably carcinogenic to humans.”

Last Friday, a groundskeeper was awarded $289 million in damages after a jury found glyphosate was a significant cause of his terminal cancer. 

Monsanto (which is now owned by Bayer) said on Monday it planned to challenge the verdict on the grounds that the judge should have barred scientific evidence.

“More than 800 scientific studies, the US EPA, the National Institutes of Health and regulators around the world have concluded that glyphosate is safe for use and does not cause cancer,” said a company representative.