The active ingredient in Roundup, an herbicide manufactured by Monsanto and the most commonly used in the U.S., is glyphosate. Numerous studies have shown that this active ingredient was within the Environmental Protection Agency’s accepted levels of toxicity. But the studies stopped there. Now new research is pointing to the inert ingredients in Roundup as being toxic, in fact, so toxic that they can harm cells. One specific inert ingredient, polyethoxylated tallowamine, or POEA, was more deadly to the cells of pregnant women and the cells in umbilical cords and fetuses than the herbicide itself. The French research team at University of Caen said its results highlight the need for health agencies to reconsider the safety of Roundup.