Genetically Manipulated Food News

18 April 1997

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European Commission considers Import of GE Maize
Reasons to Exclude Bt maize
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European Commission considers Import of GE Maize

The European Commission is considering whether or not to allow Ciba-Geigy's genetically engineered maize to be imported into the European Community from the US for human and animal consumption.

There is tremendous pressure from the US government and biotechnology industry to allow the importation of this product, and there have even been intimations that refusal to admit this genetically modified maize into the European Community might have broader implications for trade relations with the US.

Important as healthy trade relations with the US are, there are other issues that are highly relevant to the importation of this maize. In particular, there are serious concerns that this product may pose risks to consumer health and to the environment.

If the Commission fails to take these issues into account in their deliberations on whether or not to admit Bt maize into the European Community, it will have favored the business interests of a single multinational corporation over the health, welfare, and fundamental rights of millions of European citizens.

Reasons to Exclude Bt maize

There are four scientific reasons to exclude Bt maize from Europe. We will first introduce all of these briefly and then elucidate each in more detail in subsequent sections.

  1. There is a virtual certainty that the importation of this product will lead to the generation of pathogenic bacteria that are resistant to the antibiotic ampicillin.

  2. Bt maize constitutes a significant risk to the health of consumers because it has not been tested thoroughly enough to assure (a) that it does not contain unanticipated allergens or toxins, and (b) that its nutritional value has not been reduced in unexpected ways.

  3. The US government and the US biotechnology industry are demanding to import this maize unlabeled and mixed with non-genetically modified maize. This deprives consumers of the information needed to choose for themselves whether to accept the health risks associated with eating these inadequately tested foods. This also deprives consumers of their fundamental right to make informed purchasing choices.

  4. Scientific evidence indicates that the cultivation of Bt maize will lead to the emergence of insect pests that are resistant to the Bt toxin. This disruption of the ecosystem is inherently undesireable, and it is also detremental to agriculture in the long run. It will not only make Ciba-Geigy's Bt corn variety obsolete, but it will also deprive organic and biological farmers of a valuable tool for pest control-Bt toxin extracted from natural Bacillus thuringiensis. Allowing Ciba-Geigy's Maize to be imported into Europe sends a green light to industry that it is acceptable to ignore serious environmental, ecological, and agricultural threats in the development and commercialization of genetically engineered products.

The following sections presents these points in more detail.

Antibiotic Resistance not only has the gene for ampicillin resistance been introduced into Ciba-Geigy's Bt maize, but in this maize variety, the ampicillin resistance gene is still linked to bacterial regulatory sequences, called promoter sequences. These promoter sequences make this gene highly active in bacteria. It is well known that many kinds of bacteria readily pick up genes present in their environment and incorporate them into their own DNA. Due to the presence of these promoter sequences, it is highly likely that any bacterium that happens to pick up this gene will express ampicillin resistance. Thus it is virtually certain that the use of Ciba-Geigy's Bt corn will generate ampicillin resistant bacteria.

The digestive tracts of both humans and livestock contain large populations of benign bacteria. Transfer of the ampicillin gene to any one of those bacterial strains will secondarily generate ampicillin resistant pathogenic bacteria, as well. Whn humans or livestock eat Bt maize the ampicillin resistance gene will be present in the digestive tract. This gene will be picked up by intestinal bacteria, conferring on them resistance to that antibiotic. Then, when at some later time that person or animal becomes infected with pathogenic bacteria, the ampicillin resistance gene can readily be transferred to that pathogen from the benign intestinal bacteria that initially picked it up.

The result will be an ampicillin-resistant pathogen, which physicians will be unable to combat with ampicillin. Already the over-use and misuse of antibiotics has generated superbugs, pathogens resistant to a wide range of antibiotics. Commercialization of Bt maize will accelerate this process, making the problem even worse.

Proponents of Bt maize do not dispute that its use can contribute to antibiotic resistance in pathogens. Instead, they attempt to justify this by claiming that antibiotic resistant microorganisms are already being generated by other mechanisms, such as incorrect use of antibiotics, and therefore the added contribution of Bt maize need not be taken seriously.

We hold to the old adage that two wrongs do not make a right. It is true that antibiotic resistant pathogens are being generated by other mechanisms. However, we seriously question the wisdom of contributing to this trend by introducing widely a new mechanism that will surely generate antibiotic resistance.

Furthermore, claims that Bt maize will make only a small contribution to the process of creating antibiotic resistant pathogens, compared to other mechanisms, is pure speculation. There is no quantitative evidence that this is the case. Especially if genetically engineered Bt crops become widely used as animal feed, the contribution could be very large.

Health Risks of Bt Maize Ciba-Geigy's Bt maize has met the current requirements for safety testing required by the US government and by the European Union. However, a careful scientific evaluation of the tests actually performed indicates that these tests have not been sufficient to assure that Bt maize is safe to eat. In the US, all testing of genetically engineered foods is voluntary. Manufacturers are not required by law to test these foods before placing them on the market. In Europe, testing is not voluntary. However, the tests required are never-the-less inadequate to detect all potential hazards in genetically engineered foods.

Two interrelated factors contribute to these inadequacies.

  1. First, the process of genetic engineering is not completely reliable and controlled. It can, therefore introduce unforeseen genetic changes into the food-producing organism, which can, in turn, lead to changes in the characteristics of the food that cause it to contain unexpected allergens or toxins, or be reduced in nutritional value. In light of this scientific fact, one might expect that regulatory agencies would have already established a highly rigorous system for testing these novel foods that is designed to detect those that could jeopardize health. Yet, the safety testing currently required falls far short of this standard. It is not capable of detecting the full range of unforeseen hazards that could occur. This problem and alternative approaches are discussed in detail in the paper Assessing the Safety and Nutritional Quality of Genetically Engineered Foods (Attached).

  2. The second factor contributing to the inadequacy of current regulations is that these regulations are based on the principle of substantial equivalence. Testing based on this principle focuses on potential risks that can be anticipated on the basis of the known characteristics of the food-producing organism that has undergone genetic modification or on the basis of the known characteristics of the genes introduced into that organism. However, testing based on this principle ignores the unexpected hazards that are an unavoidable risk when an organism has been altered using the process of genetic engineering.

In a testing program based on the principle of substantial equivalence, selected characteristics of the genetically engineered food are compared to those of its non-genetically engineered counterpart. If those selected characteristics are found to be "substantially equivalent" in the genetically engineered food and its non-genetically engineered counterpart, it is concluded that, since the non-genetically engineered food has been shown to be safe through long use, the genetically engineered food must be equally safe.

This approach is based on the tacit assumption that measurements showing that two foods are substantially equivalent with respect to certain selected characteristics imply that those two foods are substantially equivalent in all other characteristics relevant to the health and safety of the consumer. This assumption is clearly not valid, especially in light of the fact that the process of genetic engineering is inherently capable of introducing unexpected changes in the characteristics of a food.

This approach is advantageous to industry because it speeds up the process of commercialization by allowing developers to obtain certification that a given genetically engineered food is safe without ever having to directly measure characteristics, such as allergenicity, that are critical to safety. However, this approach leaves consumers highly vulnerable to undisclosed health risks of genetically engineered foods. This problem is discussed in greater detail in the attached paper, The Failings of the Principle of Substantial Equivalence in Regulating Transgenic Foods, in which alternative approaches to testing are presented that can rectify this problem.

Labeling and Segregation of Genetically Engineered Maize The US government and the US biotechnology industry are pressing forcefully to import Bt maize in a manner that obscures the fact that it is genetically engineered. In so doing they are failing to respect the right of consumers to choose for themselves whether or not to purchase and eat genetically engineered foods. They have claimed that labeling of this maize as genetically engineered is not feasible, because (a) it is impossible to distinguish it from non-genetically engineered maize and (b) it has been mixed with non-genetically engineered maize in US grain storage facilities. Both of these claims are erroneous.

Testing-A highly sensitive and rigorous test is available that can scientifically distinguish between genetically engineered and non-genetically engineered maize. This test is available in the US through Genetic ID, a US-based testing service, and in Europe through TNO Nutrition and Food Institute in collaboration with Genetic ID. TNO is an applied research organization established through an act of the parliament of the Netherlands. This test is capable of positively detecting genetically engineered maize even if it is present at only one kernel in 10,000.

Segregation-Although regulations in the US do not require genetically engineered maize to be segregated from non-genetically engineered varieties, in practice the vast majority of genetically engineered maize has been segregated informally by farmers and grain dealers. This has been done because they have been very much aware of the controversy in Europe regarding this maize. In actuality, Mycogen has promised to buy back any genetically engineered NatureGard maize (another Bt corn variety) that farmers are unable to sell on the open market, and Ciba-Geigy has already purchased a substantial portion of the harvest of their Bt corn to sell as seed for the next growing season. Segregation must already be taking place for these things to occur.

In light of the fact that less than 0.5% of the US maize harvest has been genetically engineered, and the fact that even many of the large grain dealers have been quietly segregating maize, the biotechnology industry's claims that it is impossible to obtain sufficient non-genetically engineered maize to meet Europe's needs are ridiculous, especially in light of the fact that Europe normally purchases less than 5% of the US maize harvest.

Ecological and Agricultural Damage Rapid generation of Bt toxin-resistant pests will be the primary ecological impact of the wide-spread commercialization of maize varieties that have been genetically engineered to produce Bt toxin endogenously.

Lepidopteran pests, such as the European maize borer are killed when they consume Bt toxin produced endogenously in the tissues of maize plants genetically engineered to carry the gene for Bt toxin. However, in any insect population there will be a few individuals with natural resistance to this toxin. These will survive to reproduce, and if all maize borers except those with resistance are killed by consumption of Bt toxin, then with each generation a growing portion of the maize borer population will be resistant to this toxin. Over even a few growing seasons, such selective pressure is likely to generate pest varieties that are highly resistant to Bt toxin.

At present there is no scientifically proven strategy for preventing the emergence of resistant insects. Industry has proposed a voluntary program for using "refugia" to prevent or slow the development of Bt-resistant insects. The refugia concept is a simple one: if in a given area some maize is available that does not carry the Bt toxin (these plots are called refugia), maize borers that are not resistant to Bt toxin will survive to reproduce, thereby diluting out the selective effect of Bt toxin on the next generation of maize borers.

The refugia concept is certainly a promising one. However, no research has been done to demonstrate empirically whether or not refugia will be effective. Instead of carrying out such research, the US government has accepted industry's refugia plan without scientific evaluation. The government has allowed Ciba-Geigy and Mycogen to market Bt maize seed to farmers on a large scale, based on the promise that they will encourage farmers to voluntarily create refugia along the perimeters of their fields. This policy has been established in spite of strong objections from a large number of highly respected ecologists, entomologists, and molecular biologists.

In practice, the refugia program has been sadly ineffective. As formulated, the plan called for refugia representing from 15 to 25% of total maize acreage. However, in practice farmers have been unwilling to "waste" such large portions of their acreage in this way. Instead, much smaller refugia have often been created, and in many cases, even these were mishandled. For instance, many farmers completely negated the function of their refugia by spraying them with chemical insecticides. This allowed them to harvest marketable maize from their refugia, but spraying killed the Bt toxin-sensitive insects that the refugia were designed to preserve. Clearly a voluntary refugia program is not adequate to avoid the generation of Bt toxin-resistant pests.

This approach has serious implications, not only for farmers who are growing genetically engineered Bt maize, but also for organic, biological, and ecological farmers. Organic farmers have been using Bt toxin as a topical pesticide for many years. They spray their fields with a crude extract from Bacillus thuringiensis to kill maize borers. Because the toxin is rapidly destroyed by UV light, topically applied toxin is present in the field for only a few days. This is a sufficient period of time to substantially reduce the maize borer population, and control the pest, but not long enough to select for Bt toxin-resistant variants. As a result, resistant pests have not emerged, and Bt toxin has been used successfully for many years, and is considered a highly valuable tool in the hands of organic farmers.

The rapid generation of insects resistant to Bt toxin, due to the use of genetically engineered Bt maize, will not only make genetically engineered Bt maize varieties obsolete within a few growing seasons, but will also deprive organic farmers of a valuable tool-topically applied Bt toxin-that they have come to rely upon to protect their crops.

In summary, there is abundant scientific justification for barring Ciba-Geigy's Bt maize from the European Community. We call for the European Commission to take a strong position on this issue in which they exclude this potentially harmful product from Europe. Such a position will protect the health and safety of European citizens and will also protect the ecosystem.

Richard Wolfson, PhD Campaign to Ban Genetically Engineered Food

Natural Law Party 500 Wilbrod Street Ottawa, ON Canada K1N 6N2 Tel. 613-565-8517 Fax. 613-565-6546 email: NLP Website:

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