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Asked by spkspk to Andy, Cathie, Jules, Les, Ricarda on 24 Jun 2012.
Question: Given that many plant species are capable of propagating - without human intervention - over substantial distances[1] and that there have already been documented cases of GM crops invading land on which they were not planted, if the widespread planting of GM crops is permitted then it seems to me that there is no reasonably economic set of measures which will ensure consumers will always have the option to buy non-GM food at reasonable prices. I.e. it seems to me that eventually, only crops carefully guarded from contamination - e.g. grown under glass or plastic, with regular spot checks to guard against accidental ingress via doors/windows - would be able to be guaranteed to be free of GM contamination; and clearly the labour and infrastructure costs would make such crops significantly more expensive to produce than if open field GM crops were disallowed and the safeguards were not necessary. This would lead to a situation in which only the wealthiest members of society would be able to afford to keep their diets GM-free. Are my concerns unfounded? NB: Please don't reply to the question by saying that GM food is perfectly safe and no one should feel any need to keep their diets GM free: such a reply would be both patronising, and a failure to answer my question! [1] See Darwin's work on this, for instance.
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Les Firbank answered on 24 Jun 2012:
Many crops produce their seed through pollination by the wind or by insects, and while most pollen travels only a few meters, some can travel further, and so can jump from a GM crop to another crop of the same species in a neighbouring field. A lot of scientists have looked at separation distances between GM and non-GM crops to make sure that such an event is very rare, but there is still a chance of that a small proportion of the seed may contain GM. The government requires separation distances are in the order of 30-110m, which are intended to keep levels of GM seeds to below 0.3% (or they would be, if GM crops were grown in this country). Also, farmers would need to clean machinery to make sure gm crops don’t accidentally get mixed up with other crops.
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Andy Stirling answered on 25 Jun 2012:
This is a nicely-phrased question. I agree that these issues of choice and reversibility are crucial. And I agree that they are relevant, even where there is a judgement that the safety or environmental issues are negligible. Where there exist uncertainties or concerns on this score, the question becomes even more important. That it remains so often effectively unanswered is very significant feature of the current debate.
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Julian Little answered on 26 Jun 2012:
Hi spkspk – possibly the longest question I’ve ever seen. Les is right in saying separation distances are important – in the UK, such “coexistence measures” have been studied in detail by SCIMAC – take a look at http://www.scimac.org.uk.
Moving on from this, you are quite right when you say that ensuring that all food is entirely GM is impossible – in the same way that if you look carefully enough, you can find radioactivity in carrots (or apples, or coffee, or anything) or mycotoxins in bread, or stones in a bag of peas, or non-durum wheat in pasta, or non-organic ingredients in organic food. The natural world does not work on absolutes. So what do we as members of the human race who have an inbuilt desire to deal with absolutes or as close as we can to having them, do about it? We put in thresholds. What are thresholds? Well, we say that as long as item X has less than y% of Z in it, then you can sell item X as item X. If however, you have more than y% of Z in item X, you either cannot sell item X as item X or you say that “this is item X (and it contains some Z in it)”.
OK, so what does that mean in the UK (and the rest of the European Union) when it comes to GM? It means that under EU law, if all the ingredients in a food stuff (for example, the wheat, cheese, tomato, vegetable oil, pepperoni, etc of a pizza) are more than 99% non-GM, then that pizza does not need to contain a GM label. If ANY of the ingredients (for example the vegetable oil) has more than 0.9% GM content, then the whole pizza will have to be labelled as GM under its table of ingredients. I should say that different parts of the world have different views on this – in some countries they have thresholds for labelling, in other parts of the world the presence of GM is very normal and labelling is not required.
So threshold in Europe allows choice – choice for farmers and consumers who wish to choose to grow a GM crop or eat GM food, and choice for those people who wish to avoid it. Just the same as there are thresholds for the presence of non-organic food in organic food to avoid incidents where organic food would otherwise have to be relabelled as non-organic if a tiny proportion of it were found to be non-organic.
Perfect? No. Practical? Yes
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Ricarda Steinbrecher answered on 27 Jun 2012:
One aspect of what you are asking is the co-existence question. Can GM and non-GM plants and farming co-exist, so that people can choose whether they consume GM or non-GM? And that farmers can chose to continue growing GM-free? A lot of time has been spent on discussing co-existence – how far apart GM and non GM plants need to be in order to be sure there is no contamination – cross pollination or gene flow – between them. Many claims have been made about how far the wind will carry maize, oilseed rape or wheat pollen or how far some insects can travel. We know that some pollen – mainly from trees – can travel thousands of miles. Depending on conditions encountered by pollen, viability may be reduced. Then of course there is the issue of contamination from spillage or from machinery that has not been cleaned properly. And ‘mingling’ has become an issue aswell.
As a result of considering all this, I would say that any attempt at co-existence means inevitable contamination by GM produce of non-GM produce, especially members of the same or related crops, to say nothing of honey. This means that GM crop growers have little to fear, but non-GM and organic growers will sooner or later find that their produce contains a proportion of GM. Indeed the thresholds of contamination in the EU were developed for just this reason.
To keep food that is GM free we would – theoretically – have three options:
1) don’t grow GM food crops (and don’t grow traits that have been put into crops/plants that are used as a food source);
2) put all GM into green-houses (or distant islands);
3) put all non-GM into green houses (or distant islands).Option 1 would undoubtedly work for the purpose of avoiding contamination and cross breeding.
Are options 2 and 3 feasable, or even do-able? Option 2 is not feasible, as seeds or fruit will easily get out for the purpose of transport and selling to customers or processors. We also know from food aid that people would safe food donations (here maize) to plant them so they would have food to harvest and to eat in months to come.
So its option 3, as suggested by you, if any at all. Not sure that people who want to have GM free would actually like their food coming from greenhouses. Doesn’t strike me as the most sustainable way of farming (especially for barley or wheat or maize), or the best way to have the full range of nutrients and variety. And what about pollinators (where they are needed) – keep them indoors? And greenhouses tend to have more problems with diseases. This scenario would also not allow for GM free honey.I need to think a bit more regarding this question – but for now I can see your point. And given the case of GM oilseed rape across all of Canada, its become evident that co-existence within the same space is not possible for non-GM. It has not even be possible to keep traits apart within the oilseed rape production.
Comments
Nathan commented on :
@Les… Exactly what does it mean to “keep levels of GM seeds to below 0.3%”? Also, assuming that this is possible, wouldn’t this still result in a gradual dilution of all GM-free plants with some element of GM products? Would farmers be able to recognise plants GM plants from non-GM plants to always remove them?
My assumption is that, even if a test were devised to distinguish GM from non-GM plants on an individual basis, it would be completely infeasible to implement it on a rigorous scale to remove all “GM-contaminated” plants before they reached the consumer. Likewise, I presume that it would be impossible to test every seed before use. Let’s suppose, therefore, that 0.3% of GM-contaminated plants in a supposedly GM-free crop would the next season result in 0.3% GM-contaminated seeds in the supposedly GM-free crop *plus* the next season’s contamination too. By 2050, this would already look like 11% contamination and after 50 seasons, it would be 14% contamination. Now, I’m hoping to be alive in 50 years, so this is not an irrelevant question for today’s young people.
Moreover, this is only simple exponential growth. One might in fact expect that the growth could actually be substantially worse than this simplistic calculation, because: 1) the 0.3% of contaminated crops would cross-contaminate other crops in the field at a far higher rate than that of crops in the “safely” distant GM crop fields; and 2) this affect would become more and more dramatic over time as the contaminated portion grew.
spkspk commented on :
Les, plants can propagate much further than 110m! Seeds have been recorded travelling across oceans – stuck to the mud on birds’ feet, for instance. As such, it seems a little misleading of you to mention separation distances and national policy, since although both these measures can affect the rate of contamination, neither of them can reduce it to zero, and neither of them can absolutely control where the contamination will occur.
Surely, the only way to prevent contamination would be an international ban on open field GM crops?
Jules commented on :
Hi spkspk – take a look at my comment above – the alternative is the use of thresholds which are used throughout the food supply chain today as a way of allowing choice in the market place
spkspk commented on :
Hi Julian, thanks, but your reply does not really answer my question.
You note that the presence in any of the ingredients in a product of more than x% (currently 0.9%) GM content would mean that the whole product would have to be labelled as GM. Yet this is no comfort at all if no adequate safeguards are in place to ensure farmers everywhere will have the ability in perpetuity to grow crops with GM content below that threshold. The closest Scimac comes to providing such safeguards is with their vague redress proposals, which in theory provide an economic incentive to farmers to avoid contaminating others’ crops. However, as we know, this amounts to an economic incentive to achieve the literally impossible – which is obviously ridiculous. What is more, the redress proposals have every appearance of being (intentionally, perhaps, since Scimac is obviously partisan) legally unworkable except in the most straightforward cases of contamination.
I should add that I did not say that ensuring that all food is entirely non-GM* is impossible. On the contrary, I believe it is entirely possible, by the simple expedient of an international ban on open field GM crops.
Would you agree?
* I think you may have made a slightly Freudian typo in your remark that,
pheed commented on :
Some plant species can propagate long distances – dandelions, grasses etc – but there are lots of different types of plants, and some don’t spread very easily at all. I think domestic crops are in the latter category.
Les commented on :
Most crop seeds don’t travel very far, unless on farm machinery etc, and that’s why there are rules about keeping machinery clean. Pollen goes a bit further. But a tiny number of seeds and some pollen can travel many miles, because of a strong wind, or they get stuck on a bird.
Les commented on :
It’s all about risks. If you want totally no risk of any GM material getting into non-GM, that means don’t grow GM crops in the open. But that threatens the freedom of choice of those people who want GM crops. The separation distances have been worked out to give freedom of choice and very low levels of GM seeds and pollen in non-GM crops.