Select Committee on European Communities Minutes of Evidence

Examination of witnesses (Questions 34 - 39)




  34.  Professor Burke, your attendance here is most appreciated. We have had the good fortune to see your recent address to the NFU. Would you begin by explaining your positions, previous and present, in relation to the regulation of genetic modifications?
  (Professor Burke)  Thank you, my Lord Chairman. I was chairman of the Advisory Committee for Novel Foods and Processes for nine years from 1988 to 1997. I came to the end of my term last September, but I have kept up my interest in the field and the media keep talking to me. For much of that period I was also Vice-Chancellor of the University of East Anglia, from which post I retired about two years ago. In that post I was Chairman of the John Innes Council, the John Innes Institute being the major plant-breeding biology research institute in this country. I have some previous experience in a biotechnology company in North America and also as a professor doing gene cloning at the University of Warwick. Professor Beringer and I are both scientists by background. We have been trying to steer through this new technology in an area which has aroused some controversy.

Lord Willoughby de Broke

  35.  ACNFP opposed regulatory approval for the maize produced by Novartis which contains both an insecticide and genes which in a bacteria, but not in the maize, would have conferred resistance to an antibiotic. ACRE was satisfied with the safety of the product. Can you explain the difference between the two committees' conclusions?
  (Professor Burke)  This is an interesting case study. Antibiotic resistance genes—that is, those genes that confer resistance against the action of a particular antibiotic - have been used widely in plant biology for the selection of new varieties from genetic modification for some time. Some years ago the committee that I chaired became somewhat concerned about their widespread use. We initiated a consultation in the early `nineties and produced a guidance paper for the use of these genes in 1994. All of that predates the receipt of this particular application from Ciba-Geigy (as it was then). This maize contains a gene which confers resistance to the antibiotic penicillin. It was there because of the way that the genetic material had been constructed in the bacterial host before being put into the plant. It served no useful function in the plant. We were concerned with the low risk possibility of the transfer of this gene to gut bacteria in cattle when fed the unprocessed maize, the possible activation of the gene and the production and replication of those bacteria, with subsequent transfer into the human food chain, with the low risk of increasing antibiotic resistance in the human population through the human handling of those cattle. We are talking about a low-risk situation, and we have trouble dealing with very low-risk situations. The beef on the bone controversy is an example of that. Professor Beringer and I agree that these are lower risks than that. The committee was not against the use of antibiotic resistance genes as such. The flavour-saver tomato and the Zeneca tomato paste contain an antibiotic resistance gene which we considered not to be a risk, but we thought that this one was just over the boundary and we did not recommend approval. That went to Ministers who received different advice from Professor Beringer's committee. We had a first meeting in late 1995 to see if we could agree. We did not agree. However, we agreed on the differences. ACRE is concerned about evidence of harm. It took the view that there was no increase in risk because the antibiotic resistance genes were already present to a considerable extent in the population. We believe that although that was true we should not be party to any action that increased that figure, even by a small percentage. In making that decision we were influenced by a medical member of our committee who was very concerned about antibiotic resistance and possibly the consumer representative who was also present. We are talking about a marginal decision in a low-risk case. They were more concerned about the environment, and we the particular food. They were subject to legal constraints, and we were dealing more with people's perceptions and concerns about these novel foods.
  (Professor Beringer)  Clearly, this is not an easy issue. ACRE took the view that the increment of risk was extraordinarily low. In anything we look at we do not assume that there is no risk of harm. All of the crops that we grow have within them some potential to cause harm, sometimes serious harm. For example, potatoes can be extremely poisonous. We are very used to the concept of an existing element of possible harm. Are we going to make something worse than it already is? After all, there is nothing much worse for the natural environment than agriculture. The basis of our decision was that about five per cent of people were already carrying these drug-resistant genes and the chances of that maize introducing those genes into humans and causing a health problem were unlikely to be as much as one in a million million, so it was quite low relative to five per cent. To us, it did not present a risk of harm. Therefore, we gave our approval. If one had stopped all prescriptions for ampicillin other than only in emergency use perhaps the view would have been rather different. But that is an extremely commonly used antibiotic. It is used far too often and irresponsibly and has a very high existing frequency of resistance. We did not believe that it would add to harm.
  (Professor Burke)  I tried this argument on the committee who said that nothing should be done to increase that figure, even by a minuscule amount. Therefore, one has two different attitudes to a currently agreed situation.

Lord Jopling

  36.  We have moved on a little. A number of us read an article that appeared in The Times on 4 May based on work carried out in Switzerland by the Swiss Federal Research Station for Agro-ecology and Agriculture in Zurich. It reads: "A team. . .has found evidence that the poisonous effects of the protein can spread further. It raised plant-eating insects on B thuringiensis maize plants and fed them to the larvae of lacewings - which eat crop pests. They report. . .that the death rates of the lacewings nearly doubled. . ." The conclusion reached - that is, by the journalist - was that, "This means that an insect could nibble the plant, then fly off and be eaten by a lacewing, which would die." Here one has an area where there may be a domino effect that only experience can show up. Listening to the evidence given earlier by Professor Beringer, it appears that there may be hidden effects. It may be a human being rather than a lacewing. Perhaps you would both comment on it. I know that this was a laboratory-scale experiment and that it might not be repeated in the field, but it gives rise to considerable concern.
  (Professor Burke)  This is more a matter for Professor Beringer than me because it deals with an environmental effect from a different gene. This is not the gene referred to a few moments ago but the so-called Bt gene that is present in this maize, and is the basis of the resistance to the corn borer which is a major corn pest. I also read that article which gave an example of an environmental effect upon the insect populations. We have considered the effects of Bt gene products on human populations. The evidence is that there is no toxic effect. In parenthesis, if we have any concerns about any potential toxicological effect on human populations we can refer the application to the Committee on Toxicology which may require a full toxicological analysis. We are looking at food, not environment. Professor Beringer is looking at environment rather than food.
  (Professor Beringer)  We have belt and braces as far as human safety is concerned. On ACRE there is an expert in allergenicity. We also ask questions about possible human or animal food safety. We always remind the MAFF people who are present to make sure that their appropriate committees look carefully into these for anything that we may approve for release. To go back to the lacewings, a similar report was produced in this country on ladybirds eating aphids from genetically modified plants. Yes, these are effects. The reality in terms of environmental harm is that if you keep your crop free of aphids by spraying the ladybirds will not have any aphids to eat anyhow and therefore will die. Likewise, if you kill all the insects on another crop the lacewing will not be able to eat them and the lacewing will also not multiply. This reflects what I said earlier. If one is to make crops intrinsically resistant or improve the use of pesticides one will reduce the amount of insects. One will have second-tier effects. But they are already in agriculture. There is nothing to stop one spraying as much as one wants to keep out every insect that gets anywhere near one's farm. If one travels with a MAFF adviser the advice that is commonly given is, "There's an insect there—kill it."

Lord Wade of Chorlton

  37.  How does one assess the risk? What becomes risky and what is not risky? Professor Beringer talked about a possible risk of one in a million million. The line was drawn at that. But would the line be drawn at one in a two million million chance? To me, that does not make the slightest difference to the risk. Every day I do something which is 10,000 times more risky than that. Cannot we begin getting a debate going about what risk we are talking about? What are these risks compared with the normal risks in life?
  (Professor Burke)  It is very difficult to put numbers on these. In the environment there are domino effects. Our committee has learnt to distinguish between the safety of food, for which we have absolute responsibility—we must never approve of food that we believe to be unsafe - and the perception of risk in the population. The consumer makes judgments not based on absolute numbers. He or she is particularly concerned if they—the regulators, the Government, the House of Lords or whoever - take decisions which he believes impinges on his or her freedom of choice. Food is a particularly sensitive area. For example, we have barriers to certain foods. We do not eat horses and dogs, not for food safety reasons but for religious, ethical and societal reasons. Over the past nine years we have learned that whenever we talk about new foods we are likely to raise concerns of this kind. This is not irrelevant to the issue of labelling, on which Professor Beringer and I do differ. My rather pragmatic attitude is that, first, we have an absolute responsibility for food safety. Second, we have to deal as pragmatically as we can with the issues of perception which are particularly sensitive in relation to food. They are also sensitive in relation to the environment but they stem from a different set of values.

  38.  You did not answer my question but what you said was of interest. At some stage we must begin to evaluate this matter in a way that the public understands. Merely to say that something is risky given the enormous range is not particularly helpful.
  (Professor Burke)  I agree. One of the Ministers in the previous administration referred to a Richter scale of risk. We are not in a position to place a number on the risk when there are social implications and people distinguish between their choice and others' choices. They regard some things as so risky as to be totally unacceptable. The risk of a Chernobyl-type explosion is very low indeed but it is an unacceptable risk at any level. It is not a straight numerical calculation and that makes it a lot more difficult to deal with.

  39.  Can you explain to the committee your understanding of "substantial equivalence"? It would be useful if you could briefly outline how you see the novel food regulation being used for regulatory approval for the following three products: a fruit which has not previously been marketed in the EU but is commonly eaten in other countries, for example the durian; a peach modified so that the expression of new genes results in a much smaller stone, but the flesh of the fruit does not contain the gene products; and maize oil in which the maize has been modified to change the oil characteristics and where herbicide resistance has been used for selection of the modified crop? Would you also comment on ostrich meat, which a few years ago I would not have dreamt of eating but which is now available all over the place? Many years ago when I was in the cheese business I was the first person to use ultra-filtration as a method of manufacturing cheese. That was accepted and went into the marketplace. It was then a new process that had not previously been used for that product. Would that now be considered as a novel food?
  (Professor Burke)  To answer the last question first, the committee dealt with any novel process and any change in the way food was processed: food sterilisation processes, neutron irradiation and so on. Novel foods included those which had not been genetically modified. The majority of our work lay in non-genetically modified food but novel foods that came into the country, sometimes sold in health shops, such as chaparral tea. Sometimes new fruits or oils came in. The committee was concerned with all novel foods and processes. We had to ask ourselves: What was novel? We adopted a broad definition and said that it was something to which the British population had not been exposed in the past. Reactions to foods depend sometimes on population differences. How does one assess the safety of such a novel food? We start from where we are; namely, populations all over the world have been eating foods for many hundreds of years. There is a considerable accumulation of folk wisdom about what you can and cannot eat, how it should be prepared, and so on. To return to the question, "substantial equivalence" means that you start by comparing the new case with what is already in the diet, preferably in Britain but possibly elsewhere. One uses the accumulated wisdom and experience of generations and asks: How close is the new material to what is already being eaten? Another reason for doing it is that one cannot screen novel foods in the way one screens novel drugs where commonly one gives to animals and ultimately to man much larger doses than will eventually be used. One cannot give people 10 or 100 times as many durians as anyone would want to eat. If one did there would be certain physiological effects! Substantial equivalence is not a precise definition but a judgment, and there is a series of criteria for it laid down. The committee will ask: How close to or different from is this from an existing food? If it is absolutely identical and the track record is very good there is no problem. One then asks: How different is it? Are any of these differences likely to give rise to a problem? How can we detect these problems? Ultimately, it is a matter of judgment. The committee works on a case-by-case basis, arguing about the possible risks that may ensue—in the presence of a consumer representative and an ethical adviser. Therefore, it is a process and not a dictionary definition. Going to your examples, you spoke of a fruit not previously marketed in the EU but commonly eaten elsewhere. Those are coming into the country all the time. If one goes into the market of any town one will find novel foods that may or may not have come before the committee. In general, the big importers and supermarkets are scrupulous. The small market trader may not bother. We would ask how widely durian had been eaten in the world by Anglo-Saxons, non-Anglo-Saxons, whites, non-whites and so on. Is there any suggestion that there may be a difference? What is the history? If it was clear that there had been no problems elsewhere and there was no reason to believe that there would be problems in Britain it would be cleared. Your second example was a peach modified so that it had a smaller stone. This is an interesting hypothetical example. I can only react as I would on the committee and say first, that I know nothing about what controls the size of peach stones. Presumably, a series of genes controls the size of stones because one can breed selectively for different sizes of stone. I assume that a number of genes are involved. If so, there may be secondary effects from the alteration of those genes. Therefore, the committee will ask the person making the case to do detailed chemical and biochemical analysis on the peach flesh. Is there any reason to believe that it may be different? One would ask for all the things that one could think of. One might also ask about the things that had been bred out of the peach during selective breeding. For example, it is well known that potatoes in the wild carry toxic materials that have been bred out for commercial use. But if one genetically modifies potatoes there is a real risk that those toxic alkaloids may pop up again. In a situation like that the committee will nearly always go back to the applicant and say that it wants more evidence about this, that and the other. If it was worried it would go to the Committee on Toxicology. It is a reiterative process. We have tried to help applicants over the years by refining these kinds of questions into a series of decision trees which are published. The applicant traces his product through the decision tree with a series of yes/no answers. That should provide the information that the committee needs to make the decision. That is designed to prevent an endless reiterative process back and forth to the producer. The volume of material that comes in with an application such as the one that you instance may be an inch or so thick with a lot of detailed material because the applicant will be aware of the sort of things that the committee will be asking about. That does not mean that the committee does not go back and ask other questions. Your third example was maize oil in which the maize had been modified to change the oil characteristics and where herbicide resistance had been used for the selection of the modified crop. That has happened. Herbicide resistance maize is grown and the oil is then extracted. There would be no DNA and very little protein in the oil, so there would be almost no residue of the genetic modification. However, the oil would be different. We would be very interested indeed in the changes in oil composition. The composition of oils in the human diet is a very important part of our normal health. From genetic modification and other forms of food manufacture we have had a whole series of modified oils with increased unsaturated fatty acid content, for example to replace cocoa fat. Oils are being changed all the time. One can even buy a Mars Bar that is claimed to contain fewer calories so one can eat more of them. This is based on a change in the fatty acid composition in the fat in the Mars Bar. The committee spent a lot of time considering what would be the effect on the normal population of a change in fats. In this instance one ends up talking about the role of fatty acids and normal human nutrition. What are the effects of altering it? Should we allow people to alter it? As for ostrich meat, we never thought of eating it before but today it is available in supermarkets. You can choose to eat it or not. It is labelled. It is perfectly straightforward. The supermarket will be aware from the bar codes at the end of it how much ostrich meat is sold at any particular time to any particular group of people. The market will just run that. We may have greater problems where we cannot separate the new from the unmodified. But in the case of ostrich meat it is easy: if you do not like it, do not buy it.

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