Pusztai on Dr Ian Gibson (8/6/2004)

In a speech in the House of Commons, Dr Ian Gibson who Chairs the all party Parliamentary Science and Technology Committee, authoritatively dismissed concerns over GM and said that as a scientist he could wipe the floor with his opponents. Unfortunately for Dr Gibson, Dr Arpad Pusztai has responded to his comments, exposing once again the extraordinary confection of spin, bravado and sheer nonsense with which this technology is promoted.

Multiple items follow which are worth reading in full.

from Dr Arpad Pusztai FRSE

Dear Dr Gibson,

Having just received the full text of your speech in the Commons Debate 5th May 2004 I have decided that in the public interest I must change my mind and, in addition to my previous short reply to your e-mail letter you had sent to me and Dr Brian John, to give a detailed scientific reply to the assertions made in your speech and also in your e-mail letter.  I am sure you will welcome this as part of the scientific dialogue that the government is so keen on. As I have always subscribed to the idea of openness, transparency and inclusiveness, the catchphrases of Sir John Krebs, I have decided to publish this mainly because your speech is one of the best examples of the factually unsupported assertions that, quite unlike in the House of Commons, one certainly could not get away with at scientific meetings. I shall give you a few examples:

In the House in reply to Joan Ruddock’s question you said this: “The epidemiology studies carried out in every major centre, including in the universities in the States and elsewhere, into the effects of the food (in this context GM food!), … have shown no effects whatever that correlate with the food - although I understand how difficult that is to prove.”

I am afraid, there have been no epidemiology studies, and certainly none published.  This is by the way obvious from the fact that, apart from this generalization, you could not refer to a single such study.  It is not surprising because in the absence of labeling of GM food in the USA such studies could not be carried out!  However, it is known from official statistics that in less than ten years food-related illnesses have practically doubled in the USA since the introduction of GM food into the American diet.  While the reason for this is unknown, it requires an almost foolhardy braveness to declare that everything is well in the USA and it flies in the face of the reported facts that none of these ill effects correlate with food, including GM food.

Then you go on: “I do not think that it is incumbent on me to prove that GM food is safe; the people who say it is unsafe have to prove that.”

Could you, please, let us know the law, an Act of Parliament, that places the burden of proof for deficiencies in any defective and potentially dangerous product on the purchaser and therefore absolves the manufacturer from carrying out safety checks and publishing the results of these?

“The benefits that GM has given to people, such as the provision of cheap GM soya, have been to the great advantage of the food industry and the people who live in those countries.”

Again, no evidence is presented.  In the absence of data to support your assertion most people would have reservations that the GM- is truly cheaper than the conventional soya. Cheaper in what sense, most people would ask?

I shall skip what you said on the ethical obligation as seen by the Nuffield Council on Bioethics to explore the potential benefits of GM to reduce poverty, improve food security and promote profitable agriculture in the developing countries because this is just an opinion against which one could quote many other counter-opinions but a I take strong issue with your interpretation of the BMA’s submission about the safety of GM food.  I think it is again a classical example of quoting a part of a statement that is liked by pro-GM propagandists and even politicians but keeping quiet about the strong qualifications in the same BMA statement about the safety of GM food and the effort really needed to investigate it.  You go on: “It seems to me that the evidence is piling up to say that the (GM) food is, indeed safe.  …  Although I have not the time to do so now, I am quite prepared to take my right hon. and hon. Friends for a GM-free lunch to discuss the evidence that they (i.e. the other side) put forward. I think that I can make arguments against every single, little experiment that they put forward and give another explanation, although I agree that more work needs to be done”.

These are truly confident words!  However, in your reply to the specific questions in the e-mails that Dr Brian John and I sent you, in which we asked you to describe a little bit more fully this pile of evidence that shows the safety of GM food, your reply became less confident and was rather short and selective on the examples.  You gave us precisely three examples that you thought supported your case: a Monsanto study on GM soya in 1996, a Chinese paper on studies with GM sweet peppers and tomatoes and Dr Richard Phipps’ recent paper of a production study with GM maize-fed cattle. I expect, what constitutes a pile is a matter of definition. One can reverse this argument by saying that the evidence is in fact piling up to show the health problems of GM foods reported in the published science literature (see our review!).  However, these you and other pro-GM supporters conveniently ignore. Despite this, I am afraid, I have to tell you that even though the pro-GM people shout loud as they are trying to make up for the deficiencies of their case, you and others like you are on the losing side because the evidence to show that some if not most of the GM foods do really present health risks is truly accumulating in the literature. Moreover, not to be too pedantic, regardless whether the Gasson/Burke paper was refereed or not, it was still an opinion piece and not based on new research.  In contrast, the three examples quoted by you were at least refereed publications of new research and as such one has to take them seriously.  By the way the paper by Burke in the EMBO Journal does not present any new work either and to take a very kind view of it, it is another opinion piece.

I am afraid, your three examples are not exactly in the top category of nutritional papers.  First, the Monsanto GM soya study has in fact shown what is wrong with some of the GM studies. You will find a detailed scientific criticism of the published GM soya papers in our review.  As this is published and I already made references to it, I shall only refer to one of the most glaring examples of the clever manipulation of the results done by the Monsanto scientists by hiding the inconvenient results as supplementary information deposited in the archives of a journal that could be regarded as an attempt to mislead other scientists  (see in detail in the Appendix).

The Chinese study is not a proper nutritional study (see Appendix).  This is understandable, neither sweet peppers nor tomatoes contain sufficient protein and energy to support animal growth and therefore their nutritional testing is rather difficult.  It is rather interesting that, in contrast, by referring to Prof. Tom Saunders who opines that rats do not do well on raw potatoes (incidentally in our work we used both raw and cooked potatoes!) the impression is created that apparently sweet peppers and tomatoes are the staple food for the rats.

The Phipps paper describes a production study and as such it has an obvious commercial value.

All in all, these papers can at best be described as some evidence but hardly a confident ringing approval of the safety of GM foods.

Personalizing the debate is not what one would call a high-class debate.  In this context I  think it is demeaning to refer to a well-respected scientist such as Professor Traavik (Tromso, Norway) as “a so-called leading expert in GM crops” because of a newspaper article that he may not have anything to do with.

It is also unfair (to say the least) and misleading (some people probably would use stronger language) the passage in your speech in which reference is made to our work. “His work eventually appeared in a peer review journal, which is fine, but it first appeared in newspapers and television shows. There is no evidence that his results can be repeated.  I can cite times and places where people have tried to repeat the experiments and have not had the same results.  The essence of science is to be able to repeat experiments in different labs at different times, perhaps under different conditions, and get the same results”.

I am afraid, in your letter to Dr Brian John and myself the confidence of citing times and places where people tried to repeat our experiments but failed to get the same results, is somewhat less convincing.  More precisely this is what you said in your e-mail: “Although I am aware that nobody has repeated Dr Pusztai’s experiments precisely, that is by feeding potatoes modified in this particular way to rats over an extended period, there have been a number of feeding trials”.

True, there have been feeding experiments but these were done with soya, sweet peppers and maize (see Appendix) and not GM potatoes but this can hardly be cited as evidence that by repeating Pusztai’s experiments nobody could get the same results. 

The kindest interpretation that I can put on your views, i.e. that a study carried out with one particular GM crop can be reproduced by doing a study with a totally different other crop, is that your grasp of the principles of both genetic and nutritional science is rather shaky.  It either shows up a rather embarrassing lack of understanding of the basics of gene splicing or you try to convince your fellow parliamentarians of something that you know is not so.  I am sure you know that in genetic modification each GM crop represents a unique event. For example, Bt-176 maize refers to one particular modification event and what is established for this event may not apply to another event of even the same crop.  Indeed, this is the reason why the government experts demand a case-by-case risk assessment of each crop (see for example in Professor King’s, the government chief scientist’s report). 

Nutritionally it is also very disingenuous to pretend that by looking at sweet peppers one can demonstrate that the GM potato experiments of Pusztai were wrong.  Clearly, you were influenced Professor Burke’s (another nutritional expert) views that the work done in the UK most advanced animal laboratory (the Rowett) to a well-tried and accepted design and published in the Lancet is inferior to a Chinese work published in a journal of not truly top ranking after more than three years that it was first presented at the OECD meeting in Edinburgh. I am not surprised that this work could not have been published in a top nutritional journal because of its clear deficiencies (see the Apendix for details). Finally, I am not going to say anything more about the old hobby-horse of the pro-GM people that our work first appeared in newspapers and television shows.

It then goes on: “The scientific community is almost unanimous in support but the public debate reflects uncertainty”.  This is again a sweeping generalization without any factual support. How many scientists and what percentage of the scientific community have you interviewed to allow you to make this statement?  This is a standard ploy of projecting your beliefs and then taking them as gospel truth!  But then we are back to the newspapers: “In fact, activism has not been public-led; it has been provoked by newspapers…”  Neither the biotechnology industry nor the politicians supporting it do anything wrong; it is the nasty newspapers!

However, when you appear to be running out of steam with the arguments you fall back on the age-old practice of referring to people, such as Prince Charles or your “ex friend” Lord Melchett, in a way that shows them up in a bad light, in their absence when, of course, they cannot defend themselves. Or give pious statements, such as: “But as stewards of the planet, we also have a responsibility to recognize that change is necessary if we are to feed a burgeoning world population”…  that is so general that it is almost useless.

The final passage in your speech is a real “bravura” in misinformation; it almost takes one breath away. “If anything, the Government have been too soft on this (GM) issue; that is the only reason to admonish them. They should have taken a much harder line, rather then listening to 0.00035 per cent of the population.  Unfortunately, it is not very clear from the speech how this figure has been arrived at. But of course in the House there were few people who could or would challenge these figures, after all great many of them, unlike the majority of the British population, are on your side.

I am really saddened by this whole affair when someone respected like you decide for some unknown reason to give up your previous measured and well-considered position in public life and parliament and become a cheer-leader of the pro-GM camp.  Even for that one can find possible explanations but one would and could expect a better and more professional job from someone with previous scientific training.  If this is the best that the Chair of the Science and Technology Committee of the UK Parliament can come up with in the defence of GM foods we are in a worse situation than I ever imagined.


Arpad Pusztai          June 2004

 Previous correspondence: I attach these letters for completeness sake

Dear Dr Gibson,

I was intrigued by your references to studies in which our study with GM potatoes had been repeated time and time again and found it to be wrong.

As I keep reviewing this field of potential health effects of GM foods (our last review was published in "Food Safety: Contaminants and Toxins, ed. by JPF D'Mello, by CAB International, 2003 and the next one to be published by Elsevier early next year) it would be useful for everyone interested in this topic to let me know the references to these published works that I could include them in future reviews as I unfortunately not aware of them.

Thanking you in advance

Arpad Pusztai

Dear Dr Gibson,

I do not want to appear to be patronizing but I think you stepped outside of your expertise when you made your statement to the House on nutritional or toxicological matters concerning GM foods. I do not doubt that you are a politician of good standing and you may even get away with this statement when it comes to your friends in politics but, I am afraid, your track record as a nutritional scientist is nowhere and this will be obvious to all research scientists. However, I hope that as someone with past scientific training you will understand that when you make comments which show up your deficiencies in and poor grasp of science by pronouncing on something that you do not fully understand, you will not only embarrass some of your former colleagues but also all other presently practicing scientists. I am not going to point out to you in this short e-mail the obvious mistakes and scientific nonsenses in your statement to the House but perhaps I can suggest to you to read our review on the "Potential Health Effects of GM Foods" in the book entitled Food Safety: Contaminants and Toxins (ed. by JPF D'Mello) published by CAB International in 2003 if you want to get a professional view of all the published works in the scientific literature on the topic you commented on so bravely though somewhat foolhardily. Moreover, you cannot easily dismiss this book as anti-GM propaganda because the chapter preceding ours was written by one of your favourite authors, Mike Gasson. It is perhaps still not too late to be informed on this topic of GM safety (?) of such importance for the people of this country and your constituents whom you represent in Parliament and make amends though I know the likelihood of this to happen is less then zero.

It saddens me that although by inviting me to submit my views to the Science and Technology Committee in 1999 you were instrumental in releasing me from my contractual gagging by the Rowett, and thus lived up to your duties as a true parliamentarian, your more recent actions, including your misleading statement to the House, did a great disservice to your reputation and standing in the eyes of those who had thought well of you but, even more importantly, to the truth and the people of our country.

Yours sincerely

Arpad Pusztai


This contains the scientific criticism of the three studies referred to in your speech in the House of Commons.  As I do expect that your extended public and parliamentary duties allow you sufficient time to study the three papers in depth, here I summarize some of the scientific problems with them.

The Monsanto study on GM soya:

The statistical method for comparing the GM and non-GM lines was flawed. Instead of comparing sufficiently large numbers of samples of each individual GTS with its appropriate individual parent line grown side-by-side at the same location and harvested at the same time to establish whether they were compositionally "substantially equivalent", what the authors compared was a large number of different samples from different locations and harvest times. This is all the more curious because in the authors' experiment 1 in Puerto Rico the conventional and the GTS lines were grown at the same site but the results of their analyses on these soybean samples were not included in the publication based on experiments 2 and 3 from different sites (Padgette et al., 1996).  The Puerto Rico results had been deposited with American Society for Information Science, National Auxiliary Publication Service (NAPS) as supplementary information as referred to in Padgette et al. (1996).  It could also be retrieved from the archives of the Journal of Nutrition and data showed that the GM soybean contained significantly less protein and the amino acid phenylalanine, amongst many other things and therefore it could not have supported the growth of animals as well as the parent line.  Accordingly, because the GM and non-GM samples were not substantially equivalent had these results been included in the published paper and not hidden away in the archives the GM soya could not have been approved.  In practically all heat-treated GM soybean samples from the Puerto Rico trial the amounts of the lectin and the trypsin inhibitors were significantly higher in the GM samples than in the isogenic line.  Even more curiously, heat-treatment appeared to have far less denaturing effect on the trypsin inhibitor content of the GM lines than on the parent line samples.  Although for some unexplained reason the values were from single assays on single samples (Table 6), one of the GM lines (61-67-1) appeared to have almost seven times as much trypsin inhibitor per mg sample DW than the parent.  Indeed, the values in this GM soybean approached that found in untoasted soybean seed samples.  Even the other GM line (40-3-2) contained three times as much trypsin inhibitor than the non-GM line. There were other compositional differences in these processed soybean products.  Although it is difficult to decide from single determinations what significance one can attach to them it is curious that these studies were not followed up to establish whether the differences were real or not.

The Chinese study with GM sweet peppers and tomatoes:

A Chinese study on the safety assessment of GM tomato and GM sweet pepper expressing the coat protein (CP) gene of cucumber mosaic virus (CMV) has been published.  In this it was claimed that diets based on these GM crops appear to be as safe as their comparable non-GM counterparts.  However, some of these sweeping claims are difficult to accept on the basis of the actual data in the published paper mainly because there is a lack of precision in defining some of the parameters measured in the work. Thus, one of the major omissions is that the coat protein expression level in the plants is not given and in the toxicity tests it is impossible to see what is measured without making comparisons with equivalent amounts of CP, particularly as no attempt has been made to isolate CP from the two GM plants. The nutrition study has not been described adequately, no starting- or during-the-experiment weights of the individual animals are given.  Means are no substitute, particularly when as in Figure 3 the standard deviations in the bar diagram are so big (e.g. in 3 A at 3 weeks the mean weight of the rats is about 150 ± 50 g) that makes the in-between group comparisons meaningless.  No diet composition and no animal management data are described, even though without pair-feeding no valid conclusions about weight gain, organ weights, biochemical blood indices, etc can be arrived at. The graphs and data are uninformative. The size of the most important tissues such as the small and large intestines, pancreas, etc. has not been recorded.  The methods used for histological evaluation are not detailed and therefore it is impossible to see whether the authors used appropriate methods or not.  In view of these deficiencies it is difficult to accept the authors' conclusions that these GM plants are as safe as their conventional counterparts.

The Phipps study is not an academic study concentrating on animal production.  This is valuable for the industry but it is rather uninformative about the biochemical mechanism of food-gut interaction.

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