phme writes: French scientists led by Gilles-Eric Seralini at the University of Caen (France) unveiled a study that said rats fed with NK603 corn or exposed to the weedkiller used with it developed tumors. NK603 is a corn made by US agribusiness giant Monsanto. It has been engineered to make it resistant to Monsanto's herbicide Roundup. The study, published in the peer-reviewed journal Food and Chemical Toxicology, says it is the first to look at rats over their normal lifespan of two years. In 2009, the European Food Safety Agency (EFSA) panel on GM organisms determined that NK603 was "as safe as conventional maize", based in part on a 90-day feeding study on rats.