Until recently, few scientists were willing to question the safety of genetic engineering. Today, speaking out on GM can still be career suicide, as the former environment minister Michael Meacher learnt to his cost recently, but when he accused the Government of dancing to the tune of big business at the risk of public health, he was not alone.
The industry maintains that genetic engineering is safe, but according to Meacher it hasn't been looking for dangers. The Government had only once researched the health impacts of genetically modified organisms, he said, and when the evidence pointed to dangers, "it was widely rubbished in government circles".
Nevertheless, evidence of dangers is emerging. The Royal Society has warned that GM baby foods might lead to a rise in allergies. The British Medical Association has said that we do not know enough to be able to vouch for its safety. Other scientists wonder whether GM plants containing genes that produce antibiotics might trigger antibiotic resistance in gut bacteria, a nightmare scenario the establishment has yet to investigate.
It is widely accepted that genetic engineering is not a precise technology. When a gene is removed from its context, its effects are unpredictable. That is why inserting alien genes into organisms leads to obvious abnormalities in roughly 99 per cent of cases. Since, according to the University of California, there have been no studies into the less obvious defects, it's impossible to know how many of the remaining 1 per cent are healthy.
More than 450 scientists recently signed a statement calling for a complete moratorium on the release of GM crops. But the political establishment has chosen to ignore their concerns. It argues that millions of people have been eating GM without mishap. But how does it know? GM soya-based infant formula has raised levels of oestrogen, and last year it emerged that more than 1 per cent of three-year-old American girls have pubic hair. Could there be a link? Without rigorous studies, we can't know. Only a handful of GM scientists deny the possibility of health risks. Their argument is that risk is the key to progress. But before taking such a gamble, we need to weigh it against the benefits. With GM crops, there is little evidence the benefits exist.
We're told GM crops will reduce the use of chemicals in agriculture. But most of these crops have been designed for resistance to pesticides, with the effect that more pesticides can be applied. Worse, unintended breeding between different GM varieties is leading to super-weeds that necessitate a new generation of toxic chemicals. A Canadian government study found super-weeds at every site it examined.
We're also told GM will feed the world's poor. That is nonsense. Last year, the head of Novartis Seeds admitted: "if anyone tells you that GM is going to feed the world, tell them that it is not". He's right. GM cotton farmers in India are reporting record losses. And in the US, the situation is such that even its agriculture department has questioned why farmers are growing GM crops, given their "mixed or even negative" financial impacts. Canada's and the US's mightiest farm organisations are demanding a moratorium on GM wheat.
At its height four years ago, the consumer backlash seemed unstoppable. Monsanto's share price plummeted by 40 per cent, supermarkets vowed to remove GM products, and even McDonald's announced that its fries would be GM-free. Yet the industry today is stronger than ever. How this has happened defies belief.
When Monsanto's advertising offensive spectacularly collapsed four years ago, it was forced to adopt a new strategy. Now, according to leaked company documents, its goal is to place friendly scientists on "independent" scientific committees. For the wider industry, according to biotech consultancy group Promar International, the hope "is that over time the market is so flooded that there's nothing you can do about it, you just sort of surrender".
Politicians, meanwhile, are doing what they can to help. In the US, the revolving door between industry and regulators is moving so fast that the two are indistinguishable, with President Bush tying pharmaceutical aid in the Third World to acceptance of GM. In Britain, Mr Blair takes counsel from his Science minister, Lord Sainsbury, who is Labour's biggest donor and a man with financial interests in GM; from a Food Standards Agency that spends more time attacking organic food than examining GM; and from a Royal Society awash with vested interest.
Regardless of the outcome of the Government's consultation on GM, which even some ministers admit is a "PR offensive", the debate will continue. In characteristic doublespeak, Mr Blair demands that we "proceed according to the science". But consumers smell a rat in his "science". And if it emerges that the only viable avenue for opposing contamination of Britain is civil disobedience, then I would wager that a lot of people will oblige.
Zac Goldsmith is editor of 'The Ecologist Magazine'; www.theecologist.org