British scientists this week mounted a counter-offensive to the newspaper headlines damning genetically modified food, claiming there was no justification for a ban on planting GM crops.
Their action comes after a week of controversy punctuated by a memorandum from a group of scientists supporting Arpad Pusztai, the former Rowett Research Institute scientist who last year claimed in a TV documentary that his research showed that feeding rats genetically modified potatoes caused weight reduction in organs and damaged the immune system. Dr Pusztai was suspended after the comments, pending an inquiry. He was later retired from the institute.
This week it was claimed that Dr Pusztai's findings - which the inquiry said were not justified from his data - have been supported by more recent work by Stanley Ewen, senior pathologist at Aberdeen University. The results, if they can be replicated, could, some say, have major implications for the biotechnology industry, suggesting the process of genetic modification itself may be dangerous.
The resurfacing of the story has brought with it allegations of suppression of research and of conflict of interest against science minister Lord Sainsbury. Calls for a five-year freeze on GM crops were this week led by Friends of the Earth and Greenpeace, which took out advertisements in national newspapers challenging the safety of GM foods. The call was also backed by a number of scientists including Vyvyan Howard,a toxicologist at Liverpool University.
But others questioned the research and supported the continuation of the planting of GM crops.
Chris Leaver, head of the plant science department at Oxford University, told a Biotechnology and Biological Sciences Research Council press conference: "We must not generalise from a single laboratory-based experiment. This is a complete red herring. It is impossible to conclude without seeing the research." He added that Dr Pusztai had previously published research showing the lectins concerned also promoted health in rats.
Many others called for access to Dr Pusztai's work for peer review - a standard scientific requirement for authenticity. One commentator added: "This is science by press release, not peer review." Calls for publication of data were met in part this week with the release of Dr Pusztai's alternative report on the internet by the Rowett. But the Royal Society said this was not sufficient and did not contain the raw experimental data.
A spokeswoman said: "The society wants the release of full details in the manner of a paper you would submit to a journal. This has not been released as yet and we would urge the people involved to release this data for evaluation by experts."
John Gatehouse, who headed the team at Durham University collaborating with Dr Pusztai, said the toxic effects suggested by Dr Pusztai when rats were fed GM potatoes were not necessarily caused by the engineering itself, as was being suggested. "There are other possibilities," he said, adding these include a possible build-up of natural toxins in the potatoes as a result of the plants being grown from tissue cultures.
Don Grierson, a plant scientist at Nottingham University, added: "We are now into Glenn Hoddle territory. We are into the realms of mysticism and misinterpretation. We have not seen the evidence, but there are a number of other less surprising explanations. It's highly implausible."
Ray Baker, chief executive of the BBSRC, stressed the importance of more research. "It is important the government and regulators receive scientifically informed advice. Experimental field trials are essential to provide the information required to underpin this advice. A delay would achieve nothing, except enable the UK's competitors to advance at our expense."
He added: "I cannot accept that the 20 scientists on the memorandum are representative of the scientific community. We could find 3, 000 scientists who would back the science as opposed to 20 who have been carefully selected by Dr Pusztai and Friends of the Earth.
"The results need to be placed in context and open to debate by peer review. People want openness. They don't want rumour."