House of Commons - Science and Technology

some default text...

Select Committee on Science and Technology First Report

CHAPTER ONE: GENETIC MODIFICATION, ITS BENEFITS AND RISKS

What is Genetic Modification?

6. An organism's characteristics are determined by the information contained in its deoxyribonucleic acid (DNA) which carries the genetic information which in turn determines how individual cells, and consequently the entire organism, will develop and behave. This information is divided into individual units — the genes — "in the same way that a paragraph can be divided into individual words".[3] The characteristics displayed by a plant or animal will depend on which genes it has inherited and whether or not those genes are switched on, or 'expressed', to produce specific proteins.

7. For thousands of years mankind has sought to improve the growth, yield and other characteristics of cultivated crops by selecting and cross-breeding plants (which itself involves genetic modification) which have specific desirable characteristics. Conventional breeding involves a new plant shuffling many genes from each parent with thousands of genes recombining in large groups. This raises the possibility that an undesirable gene may also be introduced. Modern biotechnologists carry out genetic modification to change crop characteristics for similar reasons. The process of modern genetic modification, that is the transfer of genes from one type of organism to another, is the same as the process of conventional breeding but the sophisticated techniques which have been developed increase the scope of what can be achieved.

8. Modern techniques in biotechnology allow deliberate changes affecting a small number of genes. A single, pre-selected and desired gene, or group of genes, can be inserted into the DNA of the new plant. Genes can be introduced into an organism from an entirely different species. Such modification is not possible by conventional breeding. Genetic modification may also involve switching off a specific gene (or genes) thus removing its influence on the characteristics of the organism.

What GM products are grown or available in the UK?

9. In 1998 around 35 million hectares of genetically modified (GM) crops, including varieties of soya, maize, tomatoes, potatoes, cotton, tobacco and oilseed rape, were planted for commercial purposes worldwide, of which some 75% was in the USA.[4] Canada, Australia and China also have significant commercial plantings of GM crops. Europe, by contrast, although a leader in research and development in biotechnology, has been slower to adopt modern biotechnology techniques in agriculture, although they have been extensively and successfully used in the development of pharmaceuticals. Limited commercial plantings of GM maize in Spain and France in 1998 formed less than 1% of the global total.

10. There have been no commercial plantings of GM crops in the UK although GM crops have been planted for research and trial purposes. The area under cultivation in the UK for these purposes is expected to be around 300 hectares in 1999.

11. Three GM foods have been approved for sale in the UK to date. These are a tomato paste, derived from GM tomatoes with an altered ripening pattern, a type of soya which is resistant to a specific herbicide and a type of maize resistant to a different herbicide. Both soya and maize (GM and conventional varieties) are used in a wide range of processed food so GM ingredients are present in many food products on sale in the UK. A number of GM enzymes have also been approved for use in food production. For instance rennet, used in the production of cheese, which is traditionally derived from calves' stomach linings, can now be replaced by a GM version. (Consequently a broader variety of vegetarian cheese is now available). The cheese itself, however, contains no GM material. Refined food products derived from GM crops may also contain no remnant of GM material. For example, it is estimated that some 80 to 90% of the global supply of soya oil is produced from GM crops and, although detectable traces of GM protein may appear in unrefined oils, such traces are removed by the refining process.[5]

Benefits and Risks

12. No human activity is entirely risk-free.[6] Certainly no food is.[7] This is not, however, a reason to trust unquestioningly in new technologies such as modern genetic modification. Risks must be identified, evaluated and minimised. However "scientific findings will not always produce the clear cut answers the public, the press and policy-makers might prefer".[8] Scientific committees advise in areas which are, by their nature, more uncertain than most. If the scientific advisory system is to function effectively all parties must accept the nature of its limitations in this regard. Science cannot offer people what they really want—total certainty. Scientists are seldom in a position to say 'never'. It is impossible to prove a negative. We agree with Dr Cunningham's statement that "There is no point in asking for certainty. We do not live in a world of absolutes; we do not live in a world of certainties".[9] What we can ask of the scientific advisory system is that it rigorously examines what is known, identifies where there are risks and uncertainties and explains to Ministers the extent to which such risks and uncertainties can be said to be a potential problem and how they can be minimised.

BENEFITS

13. GM foods potentially offer significant benefits for the public, producers and the food manufacturing industry. The Institute of Biology state that "we are certain that the potential for Genetically Modified ... Crops to contribute to the world's food supply is considerable".[10] The Chief Scientific Adviser has put the argument clearly, noting that modern intensive agricultural practices, with their high dependence on fossil fuels and chemicals, are not sustainable, he said "in the longer term we need to bioengineer crops which work with nature to reduce the need for intensive use of chemical fertilisers, pesticides, herbicides and fungicides".[11] He sees GM technology as producing an "agriculture which can feed the super-abundant human population but ... in a way which requires less input of pesticides, herbicides, chemicals".[12] Some witnesses argued that growing herbicide tolerant or pesticide resistant crops could result in the more effective use of agricultural chemicals and therefore lead to a reduction in the overall volume needed to control weeds and pests. Rather than having to spray crops with different selective herbicides to control weeds, farmers may be able to use fewer applications of a broad spectrum herbicide. English Nature told us that GM crops "have the potential to solve the environmental problems of intensive agriculture".[13] Monsanto told us that, following the introduction of GM cotton varieties in the USA, "the use of chemicals on cotton has been reduced by something like 80 to 90 per cent".[14] More immediate benefits to the consumer in the UK could include lower prices coupled with greater nutritional value or healthier food.[15] Zeneca have stated that "biotechnology has the potential to have a profound and beneficial impact on agriculture and the environment".[16]

14. The exploitation of GM technology could provide substantial economic benefits for countries with a strong science base. The UK's contribution to genetic research has been out of all proportion to its size and it is well placed to capitalise on such advances with companies such as Zeneca Plant Science running their own research programmes into GM foods and other international companies choosing to site their research centres here.[17] The Chief Scientific Adviser has pointed out that there is a huge potential market for GM food in Europe. Successive UK Governments and the European Commission have identified biotechnology as an area for future economic expansion.[18]

RISKS

15. It has also been argued that the exploitation of GM technology for food has considerable risks. These fall into two broad categories: risks to health and risks to the environment.

Risks to Health

16. Concerns over the consumption of GM food centre on four issues. The first is over the safety of the intentional changes made in the genetic make-up of crops, including consideration of any toxic or allergenic effects. For instance, some plants naturally produce toxins as a defence against pests. Generally these are either present at such low levels that they have no impact on the humans or animals which consume them or are eradicated by processing (eg cooking). Whilst genetic modification could remove or lower the level of allergens or toxins, it is also possible that levels could be increased.[19] Secondly, there is a possibility that unintentional changes may have occurred as a result of genetic modification.[20] Thirdly, it needs to be established whether a genetic modification will be inherited in a predictable manner over several plant generations. The fourth is whether modified genetic material could be transferred to organisms which occur naturally in the human gut. Of particular concern is the use of antibiotic resistance marker genes.

17. Antibiotic resistance marker genes have been used in the genetic modification process to allow researchers to trace transgenes.[21] Some suggest that the gene sequence conferring antibiotic resistance could be transferred to bacteria which colonise the human gut, and thereby assist in the spread of antibiotic resistance in humans.[22] The Advisory Committee on Novel Foods and Processes (ACNFP) assessed the risk associated with antibiotic resistance marker genes as extremely low but nevertheless recommended that researchers should stop using them and develop alternatives.[23] The spread of resistance to antibiotics is a serious threat to our ability to treat diseases but it is likely that the widespread use of antibiotic growth promoters and antibiotics as drugs are the causes of resistance, rather than the use of antibiotic resistance marker genes. The Advisory Committee on Releases to the Environment (ACRE) has made a similar statement and more recently the Royal Society has argued that "it is no longer acceptable to have antibiotic resistance genes present in new GM crops under development for potential use in foodstuffs". Alternatives are now available.[24]

Environmental Impacts

18. The direct effects of releasing GM plants into the environment have also raised some concerns. One, for example, is about "escaping genes"— where a GM plant may transfer its new genes to other plants. Transfer of genes between plants is a natural part of the normal evolutionary process and also occurs between unmodified plants. Should this happen repeatedly when genetic modifications have conferred tolerance to herbicides, it has been suggested that a new breed of plant which cannot be controlled with conventional herbicides — super-weeds as they have been termed — could emerge.[25] Such invasions also occur without genetic modification. For example, Spartina Anglica, a form of salt marsh grass, grows rampantly over British salt marshes and is a cross between a native species and an accidentally introduced species, neither of which themselves grows particularly well. Conventional crops, including organic crops, are vulnerable to cross pollenation and inadvertent chemical contamination. This is not an issue specific to genetically modified organisms (GMOs). Nor are GMOs likely to be the greatest source of contamination.

19. Biodiversity is an area of concern. Both English Nature and the Royal Society for the Protection of Birds (RSPB) state that biodiversity in the UK countryside has been in decline for a number of years. Some suggest that the cultivation of GM crops could exacerbate existing trends towards the intensification of agriculture which are in part responsible for this decline.[26] We have already noted that GM technology may reduce the use of chemicals in agriculture; but there are also arguments that cultivation of herbicide tolerant crops might allow extravagant use of herbicides which may, in turn, have an impact on plant life and consequently on the habitats and food supplies of wildlife. It has also been suggested that crops engineered to be pesticide resistant may harm non-target wildlife. Such concerns, of course, apply equally to conventionally bred crops which possess herbicide tolerance or pest resistance — an area which has received far less attention.

20. Others have pointed out that biotechnology should not be seen as the root cause of the biodiversity problems or the cause of intensive farming practices. Professor Beringer, the chair of ACRE, said the intensification of agriculture "is not a GM issue. GM is a minor part of that problem and maybe it is a solution to part of it".[27] The Chief Scientific Adviser too is concerned about the intensification of agriculture but stated that "if I had to identify one worry about the changing shape of the British countryside at the moment it would not be GM crops, it would be winter wheat, winter oil seed rape" and their effects.[28]

Public Values and Acceptability

21. Perceptions of risk and benefit play a large part in the decisions the public make over whether or not, and under what conditions, new technologies are acceptable. It can, however, take many years for technological breakthroughs to deliver widespread benefits. Consequently there is a potential risk that new technologies with the potential to deliver huge benefits may be lost in their infancy if public apprehension over risk, not balanced by immediate benefit, rises to such levels that commercial exploitation of the new technology becomes non-viable. Direct and immediate benefits to the consumer are likely to play a strong part in decision making. Also, in the case of GM foods, indeed any food, attitudes are not only dependent on an analytical assessment of risk and benefit. Other factors, such as ethical and moral considerations, knowledge of the technology and trust in the regulatory system, play a part. The Royal Commission on Environmental Pollution stated that "values are an essential element in decisions about environmental policies and standards".[29] This is no less true of decisions over the food we eat and the crops we grow.

22. The first clearance for the use of a GM material in food production in the UK was granted in 1990, when ACNFP consented to the use of a GM bakers' yeast in bread-making. Its introduction, and that of the GM rennet in cheese production, caused little concern on the part of the public.[30] Nor did the more high-profile launch of GM tomato paste in 1996 which Sainsbury's were the first to market. Sainsbury's experience illustrates a fundamental shift in public perceptions which has subsequently occurred. The paste was sold alongside its conventional equivalent but at a cheaper price and initially outsold the non-GM variety by 2:1.[31] During 1998 the volume of sales declined and "since Christmas [1998] it has reduced to a very low level indeed".[32] The paste is now being withdrawn because at the present sales rate it does "not justify its position on the shelves".[33] Sainsbury's, like many other food manufacturers and retailers, has decided to remove all GM ingredients from its own-brand goods. In every instance these decisions have been made on the basis of commercial judgement that consumers will demand choice, rather than any belief on the part of the companies concerned that the products they have been selling are unsafe.[34] Iceland, for instance, said that it had withdrawn GM ingredients from its own-brand products in response to customer concerns.[35] At the current rate at which food manufacturers are withdrawing GM ingredients or ingredients derived from GM sources from their products, there will be no market for GM food in this country.

23. As mentioned above, there are several factors which have played a part in affecting public attitudes towards GM food. A number of surveys has shown that a key factor in influencing public acceptability of GM food is consumer choice.[36] The first GM foods on the market in the UK were clearly labelled as such and non-GM alternatives were readily available. This has not been the case with other GM products such as soya and maize. Much of Europe's soya and maize comes from the US where producers, on the grounds that there is no significant difference between GM and non-GM plants, have not segregated crops and the Food and Drug Administration has not required labelling if GM products are substantially equivalent to their conventional counterparts (see paras 60-1). Thus European food processors and retailers had no way of telling whether any given batch of processed food was derived from or contained GM material. Sainsbury's told us that "It was extremely frustrating throughout 1996 and 1997 to see no action with the commodity crops" in the US and that they repeatedly asked "for a consistent treatment in terms of segregation. In the event that did not take place. The American Soya Bean Growers' Association, Monsanto and the trade associations confirmed that it could not be segregated on the farm, it could not be segregated in the supply stream".[37] Subsequent efforts by Sainsbury's and others have demonstrated that segregation is possible but in the interim UK consumers were precluded from making choices about whether or not to buy GM products.

24. Another factor contributing to the current antagonism towards GM food is the stance taken by established and influential lobby groups such as Greenpeace and Friends of the Earth, both of which have campaigned heavily against the introduction of GM foods. Greenpeace told us that it had no principled objections to GM technology per se but that its concerns resulted from an evaluation of the risks posed by release into the environment and the food chain and therefore was absolutely opposed to its use in food.[38] Campaigns, such as the Genetic Engineering Alliance's for a 5 year freeze on commercial plantings and imports of GM food and farm crops, on the basis that far too little is known about the consequences of widespread use, have exacerbated existing widespread concerns about the intensification of agriculture more generally.[39] Moreover some lobby groups have challenged the Government's scientific advisory system by calling into question the impartiality and integrity of those serving on committees (see paras 49-52).

25. The media, too, have played a key role in influencing public attitudes towards GM food. Sainsbury's found that initial media interest in GM food, at least in relation to the launch of their GM tomato paste, was "on the whole interested, curious, but fairly positive".[40] Monsanto's high profile advertising campaign during the summer of 1998 provoked further media interest and fuelled controversy. It added little to informed debate and provided fertile ground for the subsequent tone of media reporting. Against that background, one single incident would seem to have caused a fundamental shift in the tone of media reports.

DR PUSZTAI'S RESEARCH

26. On 10 August 1998, a World in Action programme was broadcast in which Dr Arpad Pusztai, then working at the Rowett Research Institute, claimed that "the effect [of feeding GM potatoes to rats] was slight growth retardation and an effect on the immune system. One of the genetically modified potatoes, after 110 days, made the rats less responsive to immune effects".[41] On the same day a Rowett Research Institute press release stated that feeding GM potatoes in experiments had led to reduced growth and immune functions and called for further research.[42] Dr Pusztai's assertions attracted massive, and unquestioning, media interest.[43] Two days later the Rowett published another press release announcing that Dr Pusztai had been suspended and would be retiring.[44] It transpired that Dr Pusztai's experiments involving GM material were incomplete and the Rowett Research Institute's press release had misreported the scientific findings of the experiments and, indeed, that the experiments referred to had not been carried out.[45] The announcement of Dr Pusztai's retirement further fuelled speculation that the authorities were attempting to suppress scientific evidence of potential dangers of GM foods and also led to Dr Pusztai receiving support from other scientists concerned at his treatment by the Institute. Moreover, Dr Pusztai's interpretation of his research data was disputed, not only by the Rowett Institute, but also by an independent statistical analysis, commissioned by Dr Pusztai himself, which found "no consistent pattern of changes in organ weights" and which questioned the validity of the design of the experiment.[46] Dr Pusztai told us that in his 110 day feeding trials, "no differences between parent and GM potatoes could be found". This directly contradicts his statement on World in Action.[47] Dr Pusztai's appearance before us attracted far more press interest than did some of our more credible witnesses. The press continues to give credibility to Dr Pusztai's claim despite it being contradicted by his own evidence.

27. A number of lessons can be learnt from this episode. The combination of naive media handling on the part of researchers and their institute pursuing a publicity agenda, aimed at securing research funding,[48] and irresponsible broadcasters in search of ratings, provided the perfect basis for the "total delirium, hysterical headlines and a series of alarmist, largely fact-free stories that suggested all ... GM foods were a threat to human health" that has followed.[49] Scientists and research institutions must recognise that they can have a major impact on public opinion, particularly when novel products are being considered. It is right that scientists should warn of possible health hazards but they must accept that such influence needs to be wielded with the utmost responsibility.

The Importance of Peer Review

28. For many years peer review in advance of publication has been accepted as the most appropriate way of ensuring scientific validity. As Professor Bainbridge, the chair of ACNFP, told us, "We must have open debate and peer review of the science—not science by press release".[50] In February 1999, nineteen Fellows of the Royal Society, stimulated by the Pusztai affair, said "it is a dangerous mistake ... to assume that all statements claiming to be scientific can be taken at face value. Good science is work that has stood up to detailed scrutiny by independent workers in the field and contributes to new knowledge and understanding. Those who start telling the media about alleged scientific results that have not first been thoroughly scrutinised and exposed to the scientific community serve only to mislead, with potentially very damaging consequences".[51] We fully support these sentiments. There need to be improvements in the way research institutes, universities and researchers present their results. Researchers and their employers must be aware of the implications of discussing partial findings publicly. We recommend that directors of research establishments and university departments should take steps to ensure that all scientific staff are able to respond effectively and competently to media pressure. This is clearly not the case at present.

Responsible Journalism

29. Journalists, too, must recognise the duty they have to report accurately, particularly on such sensitive issues as food and health. Since media interest in GM food was reawakened earlier this year there has been a continual succession of reports, implying that eating GM food would lead to all sorts of serious diseases, such as those which appeared in late April 1999 in several newspapers relating GM food to meningitis, but which are totally unsupported by evidence.[52] Not only do such stories jeopardise the future of a potentially beneficial technology but also cause undue worry and distress. Conversely, premature disclosure of technological breakthroughs raises unrealistic public expectations which may lead to disappointment. Science editors appear to be have been sidelined over this issue.[53] We recommend media coverage of scientific matters should be governed by a Code of Practice which stipulates that scientific stories should be factually accurate. Breaches of the Code of Practice should be referred to the Press Complaints Commission.

30. These media reports have resonated with understandable public scepticism towards the Government's handling of food matters following the BSE crisis and have formed the hostile background against which the scientific advisory system must deliver its advice to Government.

31. The risk the UK faces, should it prove impossible to return to a measured and informed debate on the issues relating to GM food and crops, is that any potential benefits from GM technology may be lost solely as the result of misconceptions. The Chief Scientific Adviser said that the UK must keep up with this technology because it "is a vital industry of the future. We have played a hugely disproportionate part in creating the underlying science: are we going to lose it like we lost things in the past?"[54] It would be deeply regrettable if the UK forfeited all the potential economic and social benefits offered by GM technology on the basis of unfounded scare stories. If the UK is to reject it, it should be on the basis of scientific assessments of identifiable risks or well-considered value judgements not the result of journalistic hyperbole and unfounded fear. We entirely agree with Mr Rooker MP, the Minister for Food Safety, that it is not for the Government to either promote or prevent the introduction of GM food.[55] However, the Government does have a role in ensuring that the public are adequately equipped to make informed choices. Blanket reassurances on safety are no more likely to promote rational debate or informed decision-making than some of the more extreme media coverage regarding GM foods that we have seen in recent weeks.[56] Scientific advice needs to be communicated to the public in a manner which sets out any uncertainties. The Government has a crucial role to play in explaining the risks and rewards associated with new technological developments and also in ensuring that the public has confidence in a regulatory system that is not seen to be beholden to commercial interests. We question whether the current controversy would have reached such heights if GM soya and maize had been segregated from conventional crops from the outset. GM technology and its potential benefits may be permanently lost to the UK unless there is rational debate. The Government must provide leadership in this debate but it is also incumbent upon scientists to present findings clearly and in a manner not open to misconstruction and on the media to report accurately.

Labelling

32. EU regulations require all new GM foods to be labelled as such. The regulations do not apply to GM additives or to derivatives of GM crops, such as tomato paste or refined vegetable oils, which contain no modified constituents. The Government intends to 'gold plate' these regulations by imposing additional requirements in the UK. It is also pressing the European Commission to bring forward proposals for labelling rules for GM additives. The Commission is currently developing proposals for thresholds for labelling of GM foods.

33. The current EU regulations are based on the premise that labelling requirements should only apply where the accuracy of labels can be checked by testing the product. This may meet the requirements of those who do not wish to consume GM material, but cannot address the concerns of those who do not wish to consume food derived from, or processed with, GM technologies where no modified material remains in the final product. Many retailers are actively promoting the fact that they will soon have no GM derived ingredients in their products and consumers will be making choices based on these policies. Such claims are not at present covered by the GM food labelling requirements and in many cases there is no scientific means of testing the final product in question to establish the validity of assertions of GM status. To reduce the risk of fraudulent use of GM free labels we recommend that the Government obliges retailers not to claim GM free status unless a full audit trail from seed to supermarket shelf is in place.

34. Professor Bainbridge was strongly supportive of labelling for food derived from GM crops but pointed out that, if labelling were to be fully effective, it would be necessary to reach agreement on thresholds.[57] Sainsbury's told us that if agreement were not reached on thresholds all the effort that had already been put into developing a labelling regime would be wasted as the system would not be trusted.[58] We agree. It is important that threshold levels for the labelling of GM foods are established and are understood by the public. Thresholds should be open to review as the technology to test for GM material improves. We recommend the Government pursues these objectives in its negotiations with European partners on labelling and thresholds and in other international fora.

35. The Country Landowners' Association told us that effective and meaningful labelling was also dependent on crop segregation "without proper segregation of GM from conventional crops it will be impossible to label products as GM free".[59] There has been debate over whether segregation, at least in the volumes required, is practical.[60] Professor Bainbridge told us that she considered that segregation was possible at present, but she was unsure whether it would continue to be so.[61] Similarly, Sainsbury's were not sure whether they would be able to continue to identify sources of segregated crops in the long term, although they were confident that "if there is a market requirement ... and a market demand of value to the grower and the supply chain then it can be achieved". We also acknowledge the argument made by the Country Landowners' Association that an extension of labelling requirements to animal feed products would enable farmers to make more informed choices regarding their farming practices and to pass on better information to their customers.[62] The Government should press for international agreement on regulations requiring the separation of GM from conventional crops. These requirements should also be extended to include animal feed and meat products.