The U.S. National Toxicology Program discovered that weedkiller formulations are “potentially more toxic to human cells” than the active ingredient in them would be by itself, according to The Guardian. While the government has tested the active chemical glyphosate in isolation, there have been no studies testing chemical concoctions that are often packaged as brand-name weedkiller. “We see the formulations are much more toxic. The formulations were killing the cells,” Mike DeVito, acting chief of the National Toxicology Program Laboratory, told the newspaper. “The glyphosate really didn’t do it.” The concoctions are reportedly “disrupting cell membranes” and “significantly” changing cell viability. This comes as FDA testing for glyphosate has been repeatedly shut down, despite preliminary findings suggesting the chemical is on a large amount of everyday food items.