More than two decades ago, the U.S. Food and Drug Administration (FDA) granted GMOs “generally regarded as safe” status, meaning the industry had no obligation to conduct long-term safety studies. And while GMOs don’t have what scientists call “acute” effects, what about “chronic” effects — those that come on gradually and can’t easily be tied to one cause? The French study — the most comprehensive GMO safety assessment ever conducted — highlights that concern. It involved 200 rats and spanned two years, the life expectancy of the species of rat used. Previously, the longest study had lasted 240 days, says Michael Hansen, senior scientist at Consumers Union and an expert on GMO research. Industry-funded studies typically last just 90 days.
The researchers say their results show “severe adverse health effects, including mammary tumors and kidney and liver damage, leading to premature death” from Roundup-Ready corn and Roundup herbicide, whether they were consumed separately or together.