The European Food Safety Authority (EFSA) says a recent study on the toxicity of genetically modified maize and a common herbicide is inconclusive. The study, published on 19 September, claimed to find that rats fed genetically modified maize developed tumors at a higher rate than control animals. The study received wide press attention, although it was criticized by many scientists for its design and its statistical analysis.
At the request of the European Commission, EFSA set up a task force to evaluate the study. That group released its initial report today, concluding that the study "is of insufficient scientific quality to be considered as valid for risk assessment." The study used too few rats, didn't include sufficient controls, and the paper didn't report all relevant endpoints, the task force says. It invited that the study's lead author, Gilles-Eric Séralini of the University of Caen in France, to provide the agency with more information by 12 October.
It's not clear whether Séralini will comply with that request. He told reporters last month that he would not accept any review of the study by EFSA. "It cannot be that those who authorized [Monsanto's GM maize variety] NK603 carry out the review of my data, because there would be a conflict of interest with their authority and their careers," he said at a 20 September press conference at the European Parliament in Brussels.