The debate about GM Food and GM Crops is a complex one, because there is not a common starting point for those taking part in the debate. There could be a problem with the crops due to inadequate control

Latest update here: 11th December 2007

There is now no common education, no common religion, no common philosophy, no common experience that applies to the UK public as a whole. The debate therefore boils down to an airing of views which are based on different foundations. The protagonists are almost bound to disagree on the verdict because they disagree on the evidence that comes before the introduction of the GM argument.

The purpose here is therefore first to have a look at some of the issues, and then some of the obvious GM evidence that is not disputed. We can then follow events here as they unfold

One purpose of developing GM crops is to reduce dependence on artificially manufactured fertilisers and weedkillers to produce food at the level required to sustain existing populations. It might be claimed that it is to needed to sustain a growing global population, but let us set that aside. There is no need to complicate the argument.

Some reasons for wishing to reduce this dependence are common to almost all protagonists, others may have their personal ones, but we can take it that there is broad agreement on goal, whether it is achieved through GM, Organic Farming methods, or any other approach.

There may also be a requirement to make crops less dependent on the frequent availability and quantity of water. This is an aim which may be widely shared though, again, the development of GM crops is not seen as the solution by those who have reservations about any GM development at all

Another aim of GM crops is to produce GM food with different properties with respect to longevity, robustness, regularity, nutritional content or taste. This aim is much more disputed.

The fundamental reason for all the reservations is the RISK from GM crops. The risks of GM crops are considered as very great by some people because they fear the steps taken may be irreversible. There are risks in every human endeavour, but the claim of those who are against the development of GM crops is that a crop that turns out to have characteristics which cause a problem to the environment, through our inability to control its spreading through cross-pollination or other means, could create an irreversible and uncontrollable change in the national flora and fauna. As a small island, the UK is rather more sensitive to this than our continental neighbours.

Those who are in favour of GM Crop development wished to carry out field trials to verify the effects of cross-pollination and test other properties of specific GM crops. Protesters have interfered with these for a number of reasons:

1. The test itself created an irreversible change that might not be containable
2. The test would adversely effect the status of organic producers in the locality
3. The test was in their opinion wrongly conceived or poorly executed
4. The cross-pollination limits were obviously wrongly estimated

The evidence to date is that there has been cause for concern surrounding tests conducted in the UK with respect to some or all of the above objections. There are also particular concerns about transferring inappropriate resistance to weedkillers to other plants, or that genetically installed insecticide properties would cause the evolution of resistant pests.

These objections do need to be answered, and if they can be, tests should proceed unhindered. If they cannot be answered to the satisfaction of an independent tribunal of qualified persons of good education and no prior views on one side or the other, then the tests should be changed until they can satisfy. If not, they should be abandoned.

The aim of developers of GM foods is to arrive at a superior product at the same cost, or the same product at less cost, or (best case) a superior product at less cost, without resorting to the classic economy of scale through increased production per acre or investment in plant.

Those who are against such development hold that there is no real need; that this development is just a continuation of the process whereby food production is in fewer and fewer hands, denying markets to all those who do not join the GM bandwaggon.

They also hold that there are dangers in GM food because the effect on humans is unknown.

There is no evidence whatsoever that GM food is dangerous, and there are many safeguards in place to ensure that it is not. However, should any GM food turn out to be dangerous it is hardly likely to be a problem for the nation, let alone the human race. There are many billions of us and if a few of us die before we find out there is a problem, it's not the end of the world.

The passing of food production into fewer hands is not likely to be affected by GM, one way or the other. Other factors are more likely to come into play here, and it could go either way. No evidence.    BUT SEE ENTRY FEBRUARY 5th 2007

It is unlikely that GM development of crops and food can be stopped, even if the UK takes no part in it. It is therefore important that UK institutions and scientists keep up to speed on its development. If research and development is not carried out here, it will be elsewhere. Past experience leads one to believe that even if mistakes are made, there will be a way to correct the situation. There are other possible futures, whereby agriculture and food production could improve without GM. However it is far from certain that those who are vociferous in their hostility to GM are able or prepared to form the ranks of those who would make alternatives possible, or that others are there to do it. We will probably pass through a GM revolution before settling down to a more stable period to which that revolution will have contributed but, as usual, we will have learned much more in the process.

Don't Panic!

The long awaited report on GM is now published. Makes sense. I suggest people read it.

UPDATE October 10 2003
I am glad to say that research into the methods and likelihood of cross-pollination and the formation of hybrids has been undertaken in the case of oil-seed rape. Now, research is proceeding into the possible results of this type of cross-pollination and the wider, long term consequences, and the implications where different GM characteristics are involved. Many people think this should have been investigated a lot earlier, whatever the outcome.

UPDATE FEB 26 2004
Plans to proceed with certain commercial GM planting is delayed for a year while there is further research into separation distances and liability. As with all other technological advance, we shall now discover that the progress made in the past century was only possible because as a society we accepted risk, death and all sorts of accidents in the pursuit of progress. These days, we expect to be insured and compensated. When we re-discover that unless we limit liability, insurance is impossible, it may be possible for us to proceed. It is a good thing we have got the pioneering days of aviation behind us as it would never have got off the ground in today's political climate.

The government is to be congratulated on the announcement today that some GM crops can now be grown (a variety of Maize for animal feed for a start). There will also be legal ways for certain areas to opt for GM free status if they wish. It will take a year before everything is worked out anyway (see previous paragraph). The government has thus taken public opinion into account, even if the public it is mistaken, and has taken the legitimate and recognised fears on board by restricting permission to a case-by-case licensing.

As for GM Foods, after two years and initially taking the opposite view, the British Medical Association has come round to the point of view stated here in 2002: GM Foods are unlikely to be a risk to human health. There are caveats, so I have included a BBC report here with acknowledgement. I have underlined and emphasized the most important caveat. Since this is a known caveat, it should be able to be managed.

Tuesday, 9 March, 2004, 11:33 GMT

UK doctors alter tack to back GMs

By Alex Kirby
BBC News Online environment correspondent

Genetically modified foods are highly unlikely to harm human health, the UK's medical profession says in a surprise reversal of its position 18 months ago.

The British Medical Association says it thinks there is "very little potential" for GM food to produce harmful effects.

It calls for an end to "the hysteria" it says often surrounds the GM debate.

The BMA's Dr Vivienne Nathanson said GM food had "enormous potential to benefit both the developed and developing world in the long term", but care was needed.

" The current absence of any evidence suggesting GM foods pose a threat to human health should not lead to complacency "
Dr Vivienne Nathanson, BMA

The BMA's Board of Science said in an updated position statement that more research and surveillance were still needed to address worries over the potential risks.

Sir David Carter, the board's chairman, said: "Our assessment of all the available research is that there is very little potential for GM foods to cause harmful health effects.

Vigilance needed

"However the BMA recognises the huge public concern over the impact of GM foods and believes that research is still needed in key areas to allay remaining concern about the potential risks to human health and the environment."

Dr Nathanson, the BMA's head of science, said: "The current absence of any evidence suggesting GM foods pose a threat to human health should not lead to complacency.

"Public health surveillance should be so complete that we can be certain that adverse effects from any dietary change would be recognised.

"We also need a commitment to research in key areas to minimise the potential risks to human health and the environment posed by genetically modified food."

The statement says key areas for further research include food allergies, genetic transfer, environmental impact, and risk assessment and monitoring.

The BMA told the Scottish Parliament's health committee in November 2002 that trials of genetically modified crops in Scotland should be halted immediately as a precaution to safeguard public health.

The professional medical body represents more than 13,500 doctors in Scotland and more than 80% of British doctors.

Drug worries

In its submission then, the BMA said: "There has not yet been a robust and thorough search into the potentially harmful effects of GM foodstuffs on human health."

It said the most worrying issue was the potential danger posed by GM crops in creating antibiotic resistance in humans leading to new diseases.

The submission said: "Although the risk is not yet known, any increase in the number of resistant micro-organisms through the transfer of markers from GM foods would potentially have very serious adverse effects on human health."

The Scottish Executive rejected the BMA's concern over the trials, saying it would not have supported them if there had been any question about their safety.

The UK government is today announcing its agreement in principle to allow the commercial planting of one variety of GM maize.


The German biotech company who had been planning to plant a variety of maize in for cattle fodder has decided that the process has taken so long that their product is now out of date and therefore has lost its financal advantage compared to existing conventional varieties. So it is back to the drawing board to come up with GM maize (or other crop) that has new inbuilt characterisitics to meet the new requirements for both advantage and security. The cost of meeting the UK government controls has played a part in reducing the commercial margin as well. However the company (Bayer) are still confident of a future for GM and their plans in the UK.

UPDATE MARCH 24th 2005
EU Governements are divided over the issue of allowing GM poducts onto the market. New Labelling requiements came in in 2004. Only two new products have arrived. The World Trade Organisation is shortly to rule on complaints by the USA that he EU is in breach of WTO rules.

Meanwhile in the UK, where trials of GM crops have been largely frustrated by protesters, there are still serious reservations on dangers to the environment and wildlife.

Summary: the situation so far is in a mess. GM crops are being widely used in some developing countries wirth, it is claimed, spectacular success for farmers. In Europe the public is against GM, in foods and as crops. In the UK, this anti-GM stance is even stronger. But there is too much emotion and two little unbiased scientific testing. The coming year will see a shakeout in my view.

In spite oif the fact that GM Food poses, under existing regulations, no known risk to humanity, the different approach by the public in Europe to that in the US is causing endless controversy

EU-U.S. Clash Over GMO Corn

April 15 2005

By Jeremy Smith

BRUSSELS (Reuters) - Europe and the United States crossed swords on Friday after EU experts blocked imports of U.S. maize animal feed and grains unless there is proof they are untainted by an illegal genetically modified organism (GMO).

The United States, which has challenged EU biotech policy at the World Trade Organization, called the move an over-reaction.

From next week, U.S. exports to Europe of corn gluten feed and brewers grains, a by-product of ethanol, must be certified by an internationally-accredited laboratory to show there is no presence of Bt-10 maize, a GMO that is not authorized in Europe.

These measures will be reviewed at the end of October. U.S. exporters send 3.5 million tonnes of corn gluten feed to Europe each year, a trade worth some 350 million euros ($449 million).

"Imports of maize products which are certified as free of Bt-10 will be able to continue, but at the same time we cannot and will not allow a GMO which has not gone through our rigorous authorization procedures to enter the EU market," EU Health and Consumer Protection Commissioner Markos Kyprianou said.

Last month Swiss agrochemicals group Syngenta  said some of its maize seeds sent to the EU from the United States were mistakenly mixed with Bt-10. This insect-resistant strain is similar to Bt-11, a different GMO strain that won EU approval for distribution in 1998.

Syngenta said it respected the Commission's decision "to ensure compliance with the existing regulations."

"We are fully committed to continue co-operation with all concerned parties," Mike Mack, chief operating officer of Syngenta Seeds, said in a statement.


In Europe, consumers have been far more reluctant than in the U.S. to accept GMO products, often dubbed as "Frankenstein foods," while manufacturers of GMO foods insist they are safe.

U.S. officials condemned the EU move.

"We view the EU's decision to impose a certification requirement on U.S. corn gluten due to the possible, low-level presence of Bt-10 corn to be an over-reaction," said Edward Kemp, spokesman at the U.S. mission to the European Union.

"U.S. regulatory authorities have determined there are no hazards to health, safety or the environment related to Bt-10," he said. "There is no reason to expect any negative impact from the small amounts of Bt-10 corn that may have entered the EU."

The maize mix-up occurred sometime between 2001 and 2004.

Small amounts of seeds, up to 10 kilograms, arrived in France and Spain from U.S. suppliers for research purposes. All the seeds have since been destroyed.

Some 1,000 tonnes of Bt-10 maize also entered the EU as food and animal feed but it is still not clear to which countries. Around 70 percent of this is thought to be animal feed.

Green groups said the decision amounted to an effective ban on imports of U.S. maize-based feeds for the foreseeable future.

"Today's emergency measures will be unpopular with the U.S. government and the biotechnology industry but will start to protect Europe from more contaminated products," said Adrian Bebb at Friends of the Earth Europe.


SEPTEMBER 29th 2006

GM crops are a liability not asset
Sue Mayer

The recent row over an unapproved variety of GM rice entering the food chain should act as a warning, argues Sue Mayer, director of GeneWatch UK. In this week's Green Room, she says GM crops are still more of a liability than an asset.

" The announcement in August 2006 that an unapproved variety of genetically modified (GM) rice had been found at low levels in US long-grain rice sent shock waves through the food industry.

Bayer Crop Science's GM LL601RICE had last been grown in field trials in 2001 and was not intended for commercialisation.

Although two other varieties of Bayer's GM rice have been given approval for commercial growing and use as food, neither of these are yet being grown.

All of these varieties of GM rice have been modified to be tolerant to Bayer's herbicide, Liberty (glufosinate), so farmers can use the weed-killer without harming the crop. How the contamination arose remains a mystery and awaits the outcome of a US Food and Drug Administration inquiry.

The recent rice episode follows a very similar incident in 2005 when an experimental and unapproved variety of Syngenta's GM maize, Bt10, was found to have been grown mistakenly for four years. Errors in the laboratory and poor quality control had led to the mix up.

In 2000, another GM maize, Starlink, made by Aventis (now owned by Bayer), was found in the human food chain when it had only been given approval for animal feed because of concerns about possible allergenicity. Farmers had not known or had not been able to keep Starlink separate from other varieties of maize.

In all these cases, there have been international shipments rejected, product withdrawals and legal cases costing the industry millions of dollars.

Unapproved GMOs

The reason these GM contamination incidents have such far reaching effects is that they have affected commodity crops which are being traded internationally. A GM crop does not only require approval in the country where it is being grown; most importing countries also require GM crops to undergo a safety assessment before they are allowed in.

In Europe, because a GM organism cannot be released without approval, the presence of an unapproved GM crop - at whatever level - is illegal except in special circumstances.

The exception is when a GM organism has been through a positive safety assessment in Europe but before final approval has been given, and only applies if the contamination is at a level of up to 0.5% and is "adventitious or technically unavoidable". Neither LL601RICE or Bt10 maize fall into this category.

Therefore, the sudden widespread appearance of an unapproved GM rice has had a dramatic effect. Its detection has led to product withdrawals in Switzerland, Germany, France, Sweden, Ireland and the UK. Shipments into Europe require certification that they are GM free and Japan has halted rice imports from the USA.

Bayer is being sued by several groups of rice farmers in the USA because of the effects on their markets and other claims will probably follow.

GeneWatch UK and Greenpeace run an on-line register of GM contamination incidents which gives information about all the cases of GM contamination that are in the public domain.

There are now 132 incidents on the register and they show GM contamination can arise at every stage of development - from the laboratory, to the field, to the plate.

It shows that the controls in place are prone to failure and human error is increasingly being shown to take place - people seem unable or unwilling to take the precautions required by the law or commercial demands.

For many in the biotech industry, the fuss caused by GM contamination episodes, such as those from LL601RICE and Bt10 maize, is excessive because they do not believe there is a risk to human health or the environment.

Because the full details of these GM crops are not in the public domain, an independent assessment of claims of safety is not possible.

Food worries

Whether these particular GMOs are harmful or not, their presence in the food chain demonstrates the inability of the industry to maintain separation between GM and non-GM lines.

Bayer, Syngenta and other companies are developing unquestionably more potentially dangerous GM crops that have altered nutritional characteristics, produce therapeutic drugs or industrial chemicals. Like LL601RICE and Bt10 maize, these experimental lines do not exist officially and there are no tests available for them.

To reduce the risk, governments and companies will have to screen crops from high risk countries that grow and trial GM crops.

However, because companies maintain much information about the nature of their experimental GM crops as "confidential business information", screening will only be possible for the genes that are commonly introduced as markers, so the risk of contamination remains.

Governments also need to take the failure to comply with the law more seriously.

The fine for the Bt10 contamination incident in the USA was $370,000 (£196,000) - a trivial amount for a company the size of Syngenta. Europe and Japan took no legal action. That has to change if a more serious incident is to be avoided.

Food companies must despair about the poor practice of the agbiotech industry. They have to face the public and deal with product removals and then try to obtain redress.

Insurers are likely to continue to be sceptical about providing cover for the risks arising from the use of GM crops and foods, and large biotech companies probably have to self-insure - something that will require explicit reporting to investors. GM crops still look more of a liability than an asset. "

Dr Sue Mayer is director of GeneWatch UK, a not-for-profit group that monitors developments in genetic technologies from a public interest, environmental protection and animal welfare perspective

The Green Room is a series of opinion articles on environmental topics running weekly on the BBC News website

Wheat's lost gene helps nutrition

Turning on a gene found in wheat could boost levels of protein, iron and zinc, scientists have discovered.

The gene occurs naturally in wheat, but has largely been silenced during the evolution of domestic varieties.

Researchers found evidence that turning it back on could raise levels of the nutrients in wheat grains.

Writing in the journal Science, they suggest that new varieties with a fully functioning gene can be created through cross-breeding with wild wheat.

"Wheat is one of the world's major crops, providing approximately one-fifth of all calories consumed by humans," said project leader Professor Jorge Dubcovsky from the University of California at Davis.

"Therefore, even small increases in wheat's nutritional value may help decrease deficiencies in protein and key micronutrients."

'Spectacular' results

The researchers identified a gene called GPC-B1, GPC standing for Grain Protein Content.

It is found in both wild and domesticated varieties of wheat, but in subtly different forms, indicating that it has been changed by the long history of domestication.

The results were spectacular, confirming that this single gene was responsible for all these changes
Jorge Dubcovsky
Working with a variety of wheat called Bobwhite, a staple crop whose grains are commonly used in bread, scientists "turned down" GPC-B1 activity even further using RNA interference.

RNA interference is a recently-discovered technique which blocks the expression of genes.

"The results were spectacular," said Professor Dubcovsky.

"The grains from the genetically modified plants matured several weeks later than the control plants and showed 30% less grain protein, zinc and iron, without differences in grain size.

"This experiment confirmed that this single gene was responsible for all these changes."

The researchers deduced that the reverse process - enhancing GPC-B1 activity - ought to produce plants which have higher levels of these nutrients in their grains and mature faster.

The UC Davis team is already making such varieties, not by genetic engineering but through crossing domesticated wheat plants with wild relatives.

The key is a technology called Marker Assisted Selection (MAS). This allows scientists to select which plants to cross using genetic information, rather than simply choosing them by their attributes, as farmers have done throughout the history of agriculture.

FEBRUARY 5th 2007

There is a noisy debate going on about the safety of Monsanto's GM Maize which has been modified to protect it from attack by insects. There are claims that mice fed with the maize developed more lesions on their livers and other organs than a control group. The results are disputed. The EU appears to have accepted it as safe enough to license but there are dissenting voices. In effect, only time will tell and consumer choice will decide. This comes back again to my point that the business of the planting and contamination of crops is the real issue. If a GM food turns out to be harmful, and it hs proved impossible to prevent it contaminating other crops used for seed, there is an expensive purification problem ahead. All in all we shall just have to see what happens. In the case of GM Maize I do not see anything irreversible happening to the varieties of maiz we wish to plant in the future, but growers must be able to prove they are planting and harvesting what they intend. If there is a risk of damage to the organs of consumers, that is a choice they have to make. For them to make that choice the labelling of GMO and non-GMO must be clear and correct.

Some references - but not a lot of help actually,

DECEMBER 11t 2007
An important stage in the arguments over GM Crops, reported here in the International Herald Tribune

* * *

Science and policy collide in EU over genetically modified crops
By Elisabeth Rosenthal
Sunday, December 9, 2007

BRUSSELS: A proposal that Europe's top environment official made last month to ban the planting of a genetically modified corn strain across the bloc sets the stage for a bitter war within European Union, where politicians have done their best to dance around the issue.

The EU's environmental commissioner, Stavros Dimas, said he based his decision squarely on scientific studies suggesting that there remain long-term uncertainties and risks in planting the so-called Bt corn. But when the full European Commission takes up the matter in the next couple of months, commissioners will have to decide what mix of science, politics and trade to apply. And they will face the ambiguous limits of science when it is applied to public policy.

For a decade, the European Union has maintained itself as the last major largely GMO-free swath of land left in the world, largely by sidestepping these tough questions; it kept a moratorium on the planting of crops made from genetically modified organisms while making promises of further scientific studies.

But Europe has been under increasing pressure from the World Trade Organization and the United States, which argue that there is plenty of research to show such products do not harm the environment. Therefore, they insist, normal trade rules must apply.

In fact science does not provide a definitive answer to the question of safety, experts say, just as science could not know for sure whether the Year 2000 computer bug would be a problem.

"Science is being utterly abused by all sides for nonscientific purposes," said Benedikt Haerlin, head of Save Our Seeds, an environmental group in Berlin, and a former member of the European Parliament. "The illusion that science will answer this overburdens it completely." He added, "It would be helpful if all sides could be frank about their social, political and economic agendas."

Dimas, a lawyer and the minister from Greece, looked at the advice provided by the European Union's scientific advisory body - which found that the corn was "unlikely" to pose a risk - but he decided there were nevertheless too many doubts to permit the modified corn.

"Commissioner Dimas has the utmost faith in science," said Barbara Helfferich, spokeswoman for the Environment Commission. "But, there are times when diverging scientific views are on the table." She added that Dimas was acting as a "risk manager."

Within the European scientific community there are passionate divisions about how to apply the growing body of research concerning genetically modified crops, and in particular the one known as Bt corn, which is based on the naturally occurring soil bacterium Bacillus thuringiensis, a toxin that is genetically inserted in the corn to kill pests. The vast majority of that research is conducted by, or financed by, the companies that make seeds of genetically modified organisms.

"Where everything gets polarized is the interpretation of results and how they might translate into different scenarios for the future," said Angelika Hilbeck, an ecologist at the Swiss Federal Institute of Technology in Zurich, whose skeptical scientific work on Bt corn was cited by Dimas. "Is the glass half empty or half full?" she asked.

Hilbeck says that company-funded studies do not devote adequate attention to broad ripple effects that modified plants might cause, like changes to bird species or the effect of all farmers planting a single biotechnology crop. Hilbeck said producers of modified organisms, like Syngenta and Monsanto, have rejected repeated requests to release seeds to researchers like herself to conduct independent studies of the environmental impact of the products.

In his decision, Dimas cited a dozen scientific papers in finding potential hazards in the Bt corn to butterflies and other insects.

But the European Federation of Biotechnology, an industry group, argues that the great majority of these papers show that Bt corn does not pose any environmental risk.

Many plant researchers say that Dimas actually ignored science, including that of several researchers who advised the EU that the new corn was safe.

"We are seeing 'advice-resistant' politicians pursuing their own agendas," said one researcher, who like others said he could not be quoted by name because of his advisory role.

But Karen Oberhauser, a leading specialist on Monarch butterflies at the University of Minnesota, said that debate and further study of Bt corn was appropriate, particularly for Europe.

"We don't really know for sure if it's having an effect" on ecosystems in the United States, she said, and it is hard to predict future problems. About 40 percent of U.S. corn is now the Bt variety, and it has been planted for about a decade.

"Whether Bt corn is a problem depends totally on the ecosystem - what plants are near the corn field and what insects feed on them," Oberhauser said. "So it's really, really important to have careful studies."

While Bt crops produce a toxin that kills a winged pest and its caterpillar but is also toxic to related insects, notably Monarch butterflies, but also a number of water insects. The butterflies do not feed on corn itself, but on nearby plants, like milkweed; but since corn pollen is carried in the wind, such plants can also become coated with Bt pollen.

Oberhauser said she had been worried about the effect of Bt corn on Monarch butterflies in the United States, after her studies showed that populations of the insect dipped from 2002 until 2004. But they have rebounded in the last three years, and she has concluded that, in the U.S. corn belt, Bt corn has probably not hurt Monarch butterflies.

Still, she said there was still disagreement and broader causes for worry. U.S. Monarch butterflies may have been saved by a bit of dumb luck, she said, a fluke of local farming practices. Year by year, farmers alternate Bt corn with a genetically modified soy seed that requires the use of a weed killer. That weed killer, Monsanto's Roundup, killed off the milkweed - the monarch's favored meal - in and around corn fields, so the butterflies went elsewhere and were no longer exposed to Bt.

"It's a problem for milkweed, but it made the risk for Monarchs very small," she said.

Still, she said, other effects could emerge with time and in farming regions with other practices. For example, Bt toxin slows the maturation of butterfly caterpillars, which leaves them exposed to predators for longer periods.

Time will tell if there is a real problem. "Sure, time will give you answers on these questions - and maybe show you mistakes that you should have thought about earlier," she said.

For ecologists and entomologists, a major concern is that insects could quickly become resistant to the toxin built into the corn if all farmers in a region used that corn, just as human microbes become resistant to antibiotics that are overused. The pests that are killed by modified corn are only a sporadic problem, which could be treated by other means.

They worry, too, that Bt toxin is present in wind-borne pollen. It is extremely unusual for pollen to contain poison. Most pollens "are highly nutritious, as they are designed to attract," Hilbeck said, wondering how a toxic pollen would affect bees, for example.

Having reviewed the science, insurance companies have been unwilling to insure Bt planting because the risks of collateral damage to health or environment are too uncertain, said Duncan Currie, an international lawyer in Christchurch, New Zealand, who studies the subject.

In the United States, where almost all crops are now genetically modified, the debate is largely closed.

"I'm not saying there are no more questions to pursue, but whether it's good or bad to plant Bt corn - I think we're beyond that," said Richard Hellmich, a plant scientist with the U.S. Department of Agriculture who is based at Iowa State University, who noted that hundreds of studies had been done. Bt corn could help "feed the world," Hellmich said.

But the scientific equation may look different in Europe, with its increasing green consciousness and strong agricultural traditions.

"Science doesn't say on its own what to do," Catherine Geslain-Lanéelle, executive director of the European Food Safety Agency. She noted that while her agency had advised Dimas that Bt corn was "unlikely" to cause harm, it was still working to improve its assessment of the long-term risk to the environment.

Part of the reason that science is central to the current debate is that EU law as well as WTO rules make it much easier for a country or a region to exclude genetically modified seeds in the case of new scientific evidence showing danger. Lacking that kind of justification, a move to bar the plants would be regarded as an unfair barrier to trade, leaving the European Union open to penalties.

But the science probably will not be clear-cut enough to help the EU ministers dodge the bullet.

Simon Butler at the University of Reading in Britain is using computer models to predict the long-term effect of genetically modified crops on birds and other species. But should the ministers should reject Bt corn?

"My work is not to judge whether GM is right or wrong," he said. "It's just to get the data out there."