EFSA’s assessment came nine days after the European Commission requested a review of the controversial University of Caen study.
The French study found that rats fed on a diet containing NK603 - a maize seed variety doused with Roundup weedkiller - or given water with Roundup at levels permitted in the United States, died earlier than those on a standard diet.
The food agency’s initial review said the analysis contained in the study, led by biologist Gilles-Éric Séralini, was insufficient and asked for additional evidence by 12 October.
“Considering that the study … has unclear study objectives and given its inadequate design, analysis and reporting, EFSA finds that it is of insufficient scientific quality for safety assessments,” it says.
“When conducting a study it is crucial to ensure a proper framework is in place,” Per Bergman, who led EFSA’s work, said in a statement. “Having clear objectives and the correct design and methodology create a solid base from which accurate data and valid conclusions can follow. Without these elements a study is unlikely to be reliable and valid.”
Environmentalists want freeze on GM crops
But EFSA's findings triggered renewed criticism that the Parma, Italy-based EU agency favours the biotech industry in its safety assessments and product approvals.
“For the past decade, EFSA has consistently sided with the biotech industry and disregarded health or environment concerns about genetically modified crops,” said Mute Schimpf, food campaigner for Friends of the Earth Europe. “Instead of picking holes in peer-reviewed research, they should take public concerns seriously.”
Greenpeace EU agriculture policy director Marco Contiero demanded a moratorium on GM crops, adding: “The EU needs to redesign safety testing so that it routinely assesses impacts over the long term."
EFSA has been under fire for years for allegedly tilting towards business interests.
In February, a report by two campaign groups, the Corporate Europe Observatory and the Earth Open Source, accused the agency of repeatedly relying on industry scientists and information in risk assessments that are used by EU institutions and national governments.
“Too often it’s not independent science that underlies EFSA decisions about our food safety, but industry data,” says the report ‘Conflicts on the menu’.
Although the decade-old agency has defended its decisions, in March it announced moves to clarify disclosure rules and guidelines on who can serve as scientific experts to address criticism in its evaluations of products, including the safety of genetically modified crops.
Agency officials described the independence policy as a prioritising and consolidation of existing guidelines rather than a major overhaul of standards.
“It’s not new, it’s new that we put it up-front explicitly,” Dirk Detken, head of legal affairs for EFSA, told EurActiv at the time. “This is not going to lead to a complete overhaul of the experts we have working at EFSA right now.”