18 September 2002

WHY WE NEED GM - SPONSORED BY THE NATURAL ENVIRONMENT RESEARCH COUNCIL

The Natural Environment Research Council (NERC), a UK government [ie taxpayer] funded agency, is not just lending its name and credibility to a series of 'Spiked' debates on the environment, it's putting public funding into sponsoring them.

The debates - the latest is on 'The Future of GM' in the context of the farm scale trials - are taking place on the Spiked website.

This is run by the same (strategically) rightwing pro-corporate 'Living Marxism' clique that ran LM magazine until it was sued out of existence by ITN, over its attack on their journalists as part of LM's denial of Serbian war crimes. LM also ran a series of articles denying the Rwandan genocide - articles co-authored by Fiona Fox, the current director of the pro-GM Science Media Centre.

When we drew the history of this group to the NERC's attention, they responded, "NERC is satisfied that there is no evidence suggesting that, on environmental matters, spiked have any particular agenda."

In fact, Spiked are fanatically pro-GM and oppose environmental concerns in almost any form. Guardian columnist, George Monbiot is among several journalists who have exposed their agenda and the dubious tactics of their supporters.

Relevant articles in the media section of Monbiots' website - www.monbiot.com - include

The Revolution Has Been Televised
Channel 4's Against Nature series turns out to have been made by an obscure and cranky sect.

Modified Truth
Channel 4 has hired a charlatan to make its science programmes. This man takes liberties with facts.

Far Left or Far Right?
Living Marxism's interesting allegiances.

Crimes Against Nature
A new Channel 4 series would be laughable, had it not been given three hours of prime time TV.

You can judge the Spiked agenda by the debate initiators' presentations below. We have rearranged the order to bring the one mildly sceptical piece to the top so you don't have trouble finding it. Other pieces are authored by the likes of  CS Prakash and Greg Conko, and a member of the Spiked editorial clique who argues, 'The farm-scale trials are an unnecessary obstacle to the introduction of this beneficial technology.'

When we pointed out the extreme imbalance in the views presented, Marion O'Sullivan of the NERC told us, "We have edged towards balanced and pro-GM views to start off this debate because those views are less well aired than the anti-GM views." When we queried this, Ms O'Sullivan failed to clarify how the NERC justified that assertion.

What is at issue is not just a biased debate. The NERC's sponsorship of these debates also helps Spiked to increase its credibility, to put forward the views of its own spokespeople and to increase the number of people coming to the Spiked site for information - information which outside of the 'debate' is all in one extreme direction.

The strategy is clear even on the main GM debate page which has a link to a pro-GM article unconnected with the debate that dismisses the concerns over the Mexican maize scandal as "yet another round of scare stories" from "media campaigners".

When we pointed out the evidence for the Spiked agenda and the way in which the NERC was assisting what was in effect a rabidly pro-GM environmentalist-hate group that played fast and loose with the truth, Marion O'Sullivan of the NERC told us, "I'm afraid that we shall have to agree to differ about their suitability as a forum for debate."

Read and judge their suitability for yourself. If you have any concerns, you may like to contact NERC via "Marion O'Sullivan" <mjo@nerc.ac.uk>
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Sponsored by the Natural Environment Research Council

Why do we need the UK farm-scale trials?
http://www.spiked-online.com/sections/science/debates/GM/default.htm

Join the Spiked Online debate:
http://www.spiked-online.com/sections/science/debates/GM/default.htm

Discussion - all postings
http://www.spiked-online.com/Sections/Science/Debates/GM/Responses.htm

Spiked has launched a series of debates to provoke critical thinking on key scientific issues... NERC is sponsoring this series of debates on environmental issues with the aim of stimulating dialogue in the wider social and ethical context of issues in which science plays a part.
 
 
Current debate

Why do we need the UK farm-scale trials?

Why we need the farm-scale trials
Les Firbank
leader of the UK farm-scale evaluations of genetically modified crops
'The farm-scale evaluations are essential if we are to make informed decisions about growing GM crops without harming wildlife.'

Let the sowing begin
Tony Gilland
science and society director, Institute of Ideas
'The farm-scale trials are an unnecessary obstacle to the introduction of this beneficial technology.'

A political con
Robin Grove-White
professor of environment and society, Lancaster University 'The trials were born out of political necessity and should be seen for what they are: a pioneering toe-in-the-water, rather than the last word.'

GM in perspective
Gregory Conko and CS Prakash
Gregory Conko is director of food safety policy with the Competitive Enterprise Institute.
Dr Channapatna S Prakash is professor of plant molecular genetics at Tuskegee University
'If the field trials are allowed to progress unmolested, Britons will find that they show GM crops to have real environmental benefits

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A POLITICAL CON
September 16, 2002
Spiked Online
Robin Grove-White
http://www.spiked-online.com/articles/00000006DA0A.htm

'The trials were born out of political necessity and should be seen for what they are: a pioneering toe-in-the-water, rather than the last word.' - Robin Grove-White professor of environment and society, Lancaster University Whatever their merits as science, the UK farm-scale trials risk being remembered as a political con. As they near completion, it is vital that their very real limitations are understood, as much as their strengths. The trials programme emerged as an ingenious political expedient in early 1998. It was the UK government's response to a dilemma for which it had found itself unprepared.

In late 1997 and early 1998, controversy about the prospect of GM crops and food was beginning to crystallise in Britain. Following the first highly provocative imports of American GM soya, there had been little time for public debate.

But as media attention built, increasing numbers of people began to raise concerns.  Non-governmental organisations (NGOs) such as Greenpeace, Friends of the Earth and the Five-Year Freeze coalition argued for a moratorium on the commercial introduction of GM. Supermarket chains became aware of rising resistance by consumers - which in turn fed through to major food manufacturers like Unilever and Nestlé. By the end of 1998, Monsanto's PR consultants reported a 'meltdown in consumer confidence'.  Yet even while the public mood was shifting in this way, European Union (EU) consent already existed for the commercial release of certain GM crops (especially maize). This meant that the government was under strong pressure from the industry to allow full plantings programmes to go ahead.

Caught between this legal rock and a political hard place, the government latched on to arguments made by English Nature and the Royal Society for the Protection of Birds (RSPB) about the paucity of ecological understanding of the potential effects on biodiversity of the changed herbicide regimes that would be associated with the introduction of GM varieties of rape, maize and beet. Under EU law (the 1990 Deliberate Release Directive), delay to product distribution could only be permitted if a member state had grounds for suspecting specifiable risks to health or the environment. So the government gained the justification it needed to negotiate a delay while further research was undertaken.

With the agreement of the industry, English Nature, the RSPB, and the Advisory Committee on Releases into the Environment (ACRE), a research programme was devised and funded.  The focus was not on the inherent safety of GM technology. That issue, the government claimed, had been addressed through the established regulatory machinery (ACRE and its product-by-product risk assessments). The trials were to focus on a particular restricted range of indirect effects - the potential impacts of changed herbicide-use associated with the GM crops in question.

So the farm-scale trials were born - a scientific programme, but one shaped by legal constraints and political contingencies.

The political origins of the trials programme gave them great significance for the government, as public controversies around GM intensified from mid-1998 onwards. In the circumstances, there was a strong temptation for spokesmen to oversell them.

Inflated official claims abounded in 'fact sheets' and ministerial statements: 'These trials will ensure the managed development of GM crops in the UK takes place safely', ministers assured.  The trials, they said, 'will show whether there is evidence of...risk of harm either to human health or the environment'.

In its subsequent review of the programme in 2001, 'Crops on Trial', the Agriculture and Environment Biotechnology Commission (AEBC) criticised such assertions as exaggerated and misleading. Scientists close to the programme are aware of the dangers of these misapprehensions, for public respect towards science, as much as for the future of biotechnology.

As the programme got under way, more sources of controversy emerged. When farms up and down the country were selected for experimental plantings, they became the focus of more general concerns about GM. Anxieties about 'contamination' of adjacent farms (organic or otherwise) by gene-flow from the plants, concerns about soil and water impacts, resentments about the imposed, non-consultative character of the trial sites, pressure on 'trial' farmers from their neighbouring communities - all of these fed the wider climate of unease about the very principle of GM agriculture in Britain. This sceptical public mood found other indirect forms of expression. In several cases, direct actions against specific trial sites by groups such as Greenpeace and Genetic Snowball found sympathetic juries, reluctant to convict citizens arguing that the trials themselves constituted a serious ecological threat - and, to organic farmers and beekeepers, an economic threat.

The farm-scale trials rumble on. The results, which many expect to be modestly illuminating but inconclusive, will start to emerge in the second half of 2003. The AEBC has underlined their restricted scope, emphasising that the government should not 'exaggerate their significance'. Yet there are indications that ministers continue to regard the trials as key to forging a wider national commitment to GM agriculture.

What are the lessons here?

There are a host of reasons for the intelligent citizen to feel concern about present pressures towards widespread (and effectively irreversible) use of GM in agriculture in a country like Britain. Contrary to official wisdom, the public is generally measured and undogmatic in its attitudes towards the technology.

Indeed, the recently published EU-funded social research study 'Public Attitudes and Agricultural Biotechnologies in Europe' by PABE highlights the extent to which most people are neither pro-nor anti-GM. Instead, they have many politically significant concerns, grounded in solid past experience of human fallibility, regulatory cock-up, technological over-promising, industrial erosion of wild nature, 'tampering' in food production - and the inevitability of 'unanticipated consequences'.

These concerns can only be addressed through serious and respectful national debate. They have little to do with the 'public ignorance about science' alleged by senior politicians and industrialists pressing for rapid deployment of GM technology in agriculture. Indeed, as the PABE study shows, the more that governments urge the primacy of narrow scientific criteria while displaying ignorance towards wider issues of social importance, the greater the mistrust and hostility they provoke.

Although it is welcome that the indirect ecological implications of GM crops have become the focus of scientific attention, the trials need to be seen for what they are: a pioneering toe-in-the-water, rather than the last word. Using the wider environment as an experimental laboratory for the trials has already alienated many people.

The trials were born out of political necessity in 1998, and as the results start to come in, they will become political again. The government has committed itself to a full and open public debate before commercialisation decisions are countenanced.

It is that debate, to which the results of the trials can make their own significant but modest contribution, that should determine the country's stance on the commercialisation of GM technology.

Robin Grove-White is professor of environment and society at Lancaster University.  He is currently a member of the government's Agriculture and Environment Biotechnology Commission (AEBC), and chair of Greenpeace UK.
 

WHY WE NEED THE FARM-SCALE TRIALS
September 16, 2002
Spiked Online
Les Firbank
http://www.spiked-online.com/articles/00000006DA00.htm

'The farm-scale evaluations are essential if we are to make informed decisions about growing GM crops without harming wildlife.' - Les Firbank, leader of the UK farm-scale evaluations of genetically modified crops

In 2001, there were around 52million hectares of genetically modified (GM) crops grown around the world, almost three quarters of which have been modified to be resistant to certain broad-spectrum herbicides. This allows for simplified systems for weed control, as a single application of a chemical can kill most of the weeds within the field, leaving the crop intact. Most of the GM crops are grown in the USA, Argentina and Canada. In 1998, four herbicide-tolerant crops - beet, maize, spring and winter oil seed rape - were all approaching approval for commercial growing in the UK. They had passed the risk assessments concerning food safety and direct environmental harm. However, English Nature and the Royal Society for the Protection of Birds (RSPB) pointed out that there was a potential for the crops to cause indirect harm to the environment. GM crops would allow more efficient weed-control than conventional crops; these weeds may include important sources of food for farmland birds, which would reduce wildlife populations that are already in widespread decline. But GM crops might also bring benefits to wildlife.  Farmers may reduce their use of herbicides that linger in the soil and which can get into water supplies - and they could delay herbicide application until later in the season, by which time nesting birds will have already used the extra cover and food sources provided by the weeds to help raise their young.

The balance between these environmental costs and benefits may even vary between different crop types, from farmer to farmer, and between different parts of the country. There was no way to test these ideas without actually growing the crops in comparison with conventional varieties. The farm-scale evaluations were established to do this. 1  We are independent scientists, fully funded by government, and are looking for differences in wildlife between the half-fields grown with GM crops and the other half-fields grown with current crops. The crops are managed by farmers, so that we can also take farmer behaviour into account - and get as close as we can to how the crops would be grown commercially. We shall publish our findings on the spring-sown crops in 2003; the winter rape study will run a little later. These papers will try to explain some of the variation in wildlife in terms of differences in the way the crops have been managed - and how that differs between GM and non-GM varieties. Such information is essential if we are to make informed decisions about whether, and how, GM crops could be grown in this country without causing unacceptable harm to wildlife.

We aim to evaluate around 60 to 75 fields of each crop over a period of three years. We record plants and invertebrates (including weeds, insects, spiders, slugs and snails) in and around the fields, before, during and after the crops are in the ground. This may seem like a lot of observations - it is certainly much larger than comparable experiments in agricultural ecology. But this scale is essential if we want to be confident we can detect effects of GM cropping on wildlife, given the variation between years, parts of the country and different farms. The experiment is concerned with the effects of crop management on wildlife - especially with the effects of different weed-management systems. These effects would be the same, whether the crops had been developed using GM techniques or not: the fact that GM techniques had been used is incidental to the experimental design. However, if crops have been genetically modified, there are certain conditions for how they must be grown and managed. In particular, no GM material from the experiment is allowed to enter the human food chain.

The evaluations are working within risk assessments produced by the Advisory Committee on Releases to the Environment (ACRE), in order that GM crops do not cause harm to human health, nor direct harm to the environment (especially in terms of the potential effects of gene-flow, which is being monitored in and around the field sites by other independent scientists). The farm-scale evaluations do not address all of the questions surrounding the possible commercialisation of GM crops in Britain. They do not address the moral issues, nor the issues about globalisation and economics; these are beyond the scope of such a scientific programme. Nor do they investigate the potential effects of GM crops with different traits (for example, resistance to insect pests), or different countries and farming systems. However, the evaluations will provide clear evidence about the effects of herbicide-tolerant crops on farmland wildlife in Britain, and this evidence will be important when decisions about the commercialisation of GM crops are made. Les Firbank is an ecologist specialising in relationships between agriculture and biodiversity. He leads the UK farm-scale evaluations of genetically modified crops.
 

LET THE SOWING BEGIN
September 16, 2002
Spiked Online
Tony Gilland
http://www.spiked-online.com/articles/00000006D9FF.htm
'The farm-scale trials are an unnecessary obstacle to the introduction of this beneficial technology.' -  Tony Gilland science and society director, Institute of Ideas

The starting point of the UK's farm-scale trials is an unquestioning acceptance of negative assumptions about the destructive nature of modern farming practices.

As a result of these assumptions, over £5million has been spent on the trials, which will monitor the impact of genetically modified herbicide tolerant (GMHT) crops on farmland biodiversity; and the commercial use of a benign technology has been delayed for over four years. The formal purpose of the farm-scale trials is to test 'the null hypothesis that there are no significant differences between the biodiversity associated with the management of the particular GMHT crop and the comparable crop at the farm scale'. Back in 1998, GMHT sugar beet, maize and some oil-seed rape crop varieties had already been assessed by the regulatory authorities, and were found to pose no risk to human health or the environment. But English Nature, the government wildlife conservation agency, led a high-profile campaign for a moratorium on the commercial growth of these crops, arguing that the use of GMHT crops could have important consequences for farmland biodiversity. While English Nature acknowledged that there might be environmental advantages to the use of these crops, it warned that more efficient weed-control made possible by GMHT technology might result in fewer weed seeds being present in farmers' fields, which are an important food source for some farmland birds: 'The environmentally untested introduction of [genetically modified organisms] could be the final blow for such species as the skylark, corn bunting and the linnet, as the seeds and insects on which they feed disappear.' 1

The farm-scale trials are not attempting to assess the impact of GMHT farming practices on birds directly (though some limited observational pilot studies are underway).  Rather, a range of other so-called biodiversity 'indicator' species such as weeds, insects, slugs and snails are being measured to compare their abundance in GMHT and non-GMHT fields. But it is concern for the fate of so-called 'farmland bird' species that is the reason most usually cited for the need for the farm-scale trials. When English Nature announced its moratorium, many UK newspapers responded with concerned articles about the fate of farmland birds 2.

Things are not so simple as the critics of modern farming would have us believe. One frequently cited statistic is an index of 20 'farmland species', compiled for the government by the British Trust for Ornithology (BTO).  According to this index the population of farmland birds in the UK has declined by more than 30 percent over the past three decades.  Because this is a period over which various modern farming practices were introduced (such as increased pesticide usage and the switch from spring-sown to autumn-sown crops), it is commonly argued that those practices must be to blame for the dramatic decline of farmland birds. What tends to be ignored is that very little is known about the population dynamics of most bird species; that the interacting factors are extremely complex; and that change is the norm.  Over time, a whole variety of factors has caused populations of different bird species to go up and down. As leading British ornithologists Alexander and Lack observed over 50 years ago: '132 out of 189 breeding species, or 70 percent, have changed markedly in status during the course of the nineteenth and twentieth centuries', and there were many cases in which 'human factors do not appear to have been involved' 3 . In a commentary in the science journal Nature in 1999, ornithologist John Krebs and his colleagues pointed to the major declines in some farmland bird species, and argued that the intensification of farming meant that 'the rest of nature is bound to suffer'. But the authors admitted the difficulties of establishing causal relationships, even though they found the evidence 'by association' to be 'damning' 4 .

Others are more cautious about making such sweeping statements. For example, Dr Tim Sharrock, co-ordinator of the British Trust for Ornithology (BTO)'s first 'Bird Breeding Atlas', wrote a piece called 'Panic Ye Not' in the journal British Birds, in which he expressed dismay at 'doom-and-gloom' stories about falling bird numbers, and counselled that there 'will always be winners and losers' 5 . While the government's farmland bird index of 20 bird species showed a decline of 35 percent between 1970 and 1998, the statistic varies with the choice of bird species. The birds included by the government are those regarded by most ornithologists as farmland specialists, as opposed to generalists (which tend to be found in a wider range of habitats). However, if an index were calculated for a broader group of 42 'farmland birds' - those that BTO researchers found breeding on Common Bird Census farmland plots sufficiently frequently to index 6 - it would show either no change, or a slight increase, over the same time period 7 . Only five of the species in the government index are among the 15 species most frequently found breeding on farmland. The government index therefore provides a very partial measure of the abundance of bird life on British farms.  There is little evidence of a significant decline overall. A more balanced and objective perspective on the relationship between farming and wildlife would accept that changes in farming practices will inevitably have an impact on wildlife, but that this impact will not necessarily be a negative one. Such a perspective would not have supported the establishment of the farm-scale trials. But the current trials also need to be viewed in the broader context of the GM debate in the UK, which, since the beginning, has been driven more by prejudice than by scientific fact.

From 1998 onwards, endless panics about GM technology - from 'superbugs' to 'superweeds' and 'poisonous potatoes' - have been promoted, all of which play on contemporary prejudices about the frailty of nature and the destructive impact of man. Government, industry and all involved with the development of GM technology have failed at every step to counter such fears. We have heard little about the importance of human innovation, or of our longstanding ability to overcome problems when things don't go precisely to plan.

We should recognise that the farm-scale trials are motivated, not by problems facing birds or other wildlife, but by politics. The government and industry has failed to win the argument for the use of GM technology, and when the going got tough they decided to put things on hold for a while. The current farm-scale trials are an unnecessary obstacle to the introduction of a technology that has been shown to be beneficial and benign in other parts of the world. The farm-scale trials took much of the heat out of the GM debate - but as they draw to a close, tensions are again mounting. It remains to be seen whether those in authority have learned sufficient lessons to win the argument for GM cultivation.

Tony Gilland is science and society director at the Institute of Ideas, and editor of Science: Can You Trust the Experts?, Hodder & Stoughton, 2002.
 

GM IN PERSPECTIVE
September 16, 2002
Spiked Online
Gregory Conko and CS Prakash
http://www.spiked-online.com/articles/00000006DA08.htm
'If the field trials are allowed to progress unmolested, Britons will find that they show GM crops to have real environmental benefits.' - Gregory Conko and CS Prakash
Gregory Conko is director of food safety policy with the Competitive Enterprise Institute.
Dr Channapatna S Prakash is professor of plant molecular genetics at Tuskegee University

Three years after the UK government initiated its farm-scale evaluations of GM crops, the debate over genetic modification remains as heated as ever. The evaluations, intended to assess the environmental and agronomic impact of GM crops and promote confidence that government policies are based on real-world data, have accomplished few of these goals. Fields have been destroyed, equipment damaged, and farmers and their families threatened and hounded out of the programme.  Neither committed opponents of GM nor the broader public have been reassured by the tests. And, consequently, the government that launched the evaluations lacks confidence to move forward with the technology.

Critics of GM technology have opposed the trials all along, arguing that genetically modified crops could have negative impacts on the environment, such as displacing wild biodiversity and spreading genes to other crops or wild plants through cross pollination. But by ignoring the broader context in which food production has taken place over the millennia, they miss two important points. First, genetic modification is not, in and of itself, dangerous. Some types of GM crop could pose genuine and substantial environmental or human health risks, while others are safer than their conventionally modified counterparts. The fact that GM techniques were used makes the crop neither dangerous nor safe: it has no meaningful effect on the plant's risk characteristics. What does determine if plants are safe or dangerous is the traits that are transferred to them, regardless of whether this is done with advanced genetic techniques or more conventional methods. Second, every risk that has been legitimately hypothesised about GM plants has a perfect analogue in one or another conventionally bred variety.

For example, the UK farm-scale evaluations focus on crops that have been genetically modified to tolerate specific herbicides. Concerns have centred on speculation that the herbicide-tolerant plants could become invasive weeds; that the herbicide-tolerance trait could spread to wild plants through cross pollination; or that use of herbicide in conjunction with the crop could damage biodiversity. Several rapeseed varieties and at least one soybean variety have been modified with conventional breeding techniques to be herbicide tolerant. And every one of the concerns about GM herbicide-tolerant crops applies equally to conventionally modified herbicide-tolerant crops. GM is just a more effective and more predictable way of accomplishing what Mother Nature can do on her own. But, curiously, opponents of GM have raised not a whisper against more traditional breeding methods. Cross pollination with other crops is also an age-old consideration for farmers. For example, two different varieties of rapeseed are grown in many countries - one used to produce edible cooking oils, the other to produce industrial lubricants - and each can very easily cross pollinate with the other. Industrial rape is harmful if ingested because of high levels of a naturally occurring chemical that is toxic to humans. So rape for consumption and rape for lubricants must be carefully separated - far more carefully, in fact, than GM and conventional or GM and organic crops. The exact same methods developed by growers of rapeseed can be used to control cross pollination from GM crops.

Critics note that novel genes introduced into GM plants could produce proteins that are toxic, allergenic or carcinogenic. But potentially dangerous genes, proteins and other substances are routinely introduced into the food supply with conventional breeding techniques. Food-grade tomatoes and potatoes are routinely bred from wild varieties that are toxic to human beings. But we are not concerned about the unsafe products of conventional breeding because plant breeders, biologists and farmers have identified methods to eliminate potentially dangerous plants before they ever make it to market. GM techniques, which allow breeders to test the genes and proteins before they are transferred, mean that ensuring the safety of GM plants is actually easier. This broader context suggests that fears about the GM farm-scale evaluations are wholly misplaced. Moreover, if the field trials are given an opportunity to progress unmolested, Britons will find that they show GM crops to have very real environmental benefits, not just hypothetical risks.

In the USA, for example, the commercial cultivation of GM crops has reduced insecticide and herbicide use and saved topsoil and other valuable resources. The non-profit National Center for Food and Agricultural Policy found that GM cotton, maize and rape allowed US farmers to reduce insecticide and herbicide use in 2001 by 21million kilograms. GM herbicide-tolerant crops have also promoted the adoption of farming practices that reduce tillage or eliminate it altogether.  Low-tillage practices can decrease soil erosion by up to 90 percent compared to conventional cultivation, saving valuable topsoil, improving soil fertility, and dramatically reducing sedimentation in lakes, ponds and waterways. Opponents of genetic modification argue that organic farming can reduce insecticide and herbicide use even more than GM crops can.  But about 20 percent of crop productivity in the industrialised countries of North America and Europe, and as much as 40 percent in Africa and Asia, is lost to insect pests, weeds and plant diseases. Organic production methods would only exacerbate yield losses, and substantially more land would have to be brought into agricultural use to compensate.

Perhaps of equal importance to Britons is the fact that, unlike many other advances in farming technology, GM crops have been shown to be scale-neutral. The small, family-run farms of which Europeans are so fond can benefit as much as large industrial farms. This could help put European growers on a more equal footing with competitors in other parts of the world.  Indeed, studies of South African and Chinese cotton-growers suggest that small farmers actually achieve higher relative benefits from GM, because expensive machinery can sometimes be made obsolete. Maybe GM critics oppose the farm-scale trials because they realise the results could hurt their case against genetic modification. For true believers, though, no amount of evidence will ever be enough. Before resigning as head of Greenpeace UK, Lord Peter Melchett told a House of Lords Select Committee hearing that his organisation's opposition to GM is 'a permanent and definite and complete opposition based on a view that there will always be major uncertainties'. Perhaps, then, the only good reason for opposing the farm-scale trials is that they are unlikely to ever satisfy GM's most devoted critics. Even the most ardent supporters of genetic modification can not claim that GM will never cause unanticipated problems. But if society demanded absolute certainty of no harm before products could be marketed, we would have to abandon not just GM, but traditional breeding as well. Genetic modification can offer tremendous benefits for the environment, for farmers and for consumers - but only if we give it a chance to prove itself.

Gregory Conko is director of food safety policy at the Competitive Enterprise Institute in Washington, DC.
Channapatna S Prakash is a professor of plant molecular genetics at Tuskegee University in Tuskegee, Alabama.
The authors are also co-founders of the non-profit AgBioWorld Foundation in Auburn, Alabama.