Scientists who published research showing that rats fed with one type of genetically modified corn suffered tumours and organ damage have been accused of employing scare tactics by the biotech industry.
But in a press conference in the European Parliament today one of the researchers on the report, Gilles-Eric Séralini, defended what he said was the "longest, most detailed study ever carried out" on the subject.
The controversy arose after French research published
in the journal Food and Chemical Toxicology
claimed that rats fed a diet of the GM company Monsanto's modified corn, or exposed to the American firm's weedkiller Roundup, developed tumours as well as liver and kidney damage.
The team from the University of Caen, including Séralini, examined 200 rats over two years. Those rats fed an exclusive diet of the seed variant NK603, which is designed to be tolerant to Roundup, or given the weedkiller itself in water at levels allowed in the United States, were much more vulnerable to premature death, they found.
In response the French government asked the country's health watchdog to investigate further, while the European Commission said the European Food Safety Authority would look into the matter in detail. But the study provoked a backlash from some, including EuropaBio, which represents the biotech industry. It published a statement rounding up what it said was the extensive criticism of the research from the scientific community.
It said doubts had been cast on the statistical methods used and the size of the control group, while describing the maize-only diet as "dubious and unrealistic". It added that the type of rat used was a problem because of its particular susceptibility to the sorts of cancer found in the test subjects. The study appeared designed "not to produce good science, but to scare people and media into forming negative opinions of GM," EuropaBio said.
Earlier Monsanto spokesman Thomas Helscher said: "Numerous peer-reviewed scientific studies performed on biotech crops to date, including more than a hundred feeding studies, have continuously confirmed their safety, as reflected in the respective safety assessments by regulatory authorities around the world." Nevertheless he said the company would examine the research closely.
However, some MEPs have demanded that the commission take immediate action in light of the new research. Jill Evans, from the Greens/European Free Alliance group said the authorisation and import of GM maize should be suspended while food safety agencies undertook independent studies.
And the European United Left/Nordic Green Left group tabled a question to health commissioner John Dalli asking whether the European Union executive would review its GM policy, whether it intended to ban all crops of Monsanto GM, and whether it would introduce new maximum residue limits for the herbicide used in Roundup.
Meanwhile Séralini criticised regulators for relying on three-month studies when they made decisions on authorising GM products, noting that the effects found in the newly published research would not have been caught in that timeframe. Speaking alongside him, Corinne Lepage MEP said there should be a "profound change in the way things work following the publication of this study".