To use all functions of this page, please activate cookies in your browser.
With an accout for my.bionity.com you can always see everything at a glance – and you can configure your own website and individual newsletter.
- My watch list
- My saved searches
- My saved topics
- My newsletter
Genetically modified food controversies
The GM food controversy is a dispute over the advantages and disadvantages of genetically modified food crops. No major health hazards have come to light since GM food was introduced 13 years ago, and close to 150 governmental and/or industry-financed studies, and at least 47 peer reviewed articles in scientific journals have been published to attest their safety. Consumer rights groups, such as the Organic Consumers Association, and Greenpeace emphasize the long term health risks which GM could pose, or that the risks of GM have not yet been adequately investigated.
Some industry scientists and economists express concern about the alleged harm delaying welfare and environmental improvements, for instance by pro-vitamin A enriched Golden rice which is said to have the potential to prevent children from Vitamin A deficiency , and insect protected Bt rice which can potentially reduce exposure of farmers to synthetic insecticides.
Other scientists and studies, however, dispute such findings and point out that Genetically Modified foods aren't tested to scientific standards before being released to the public.
In August 1998 widespread concern, especially in Europe, was sparked by a U.K. government-funded study by nutrition researcher, Dr Árpád Pusztai, regarding some of his research into the safety of GM foods.
Pusztai claimed his experiments showed that rats feed on potatoes genetically engineered to express a lectin from snowdrop had suffered serious damage to their immune systems and shown stunted growth. The lectin expressed by the genetically modified potatoes is toxic to insects and nematodes and is allegedly toxic to mammals. He was criticized by leading British politicians, the majority of scientific peers with expertise in the area and by the GM companies because the announcement of his results in a television interview preceded the scientific publication of his results. When his studies were finally published in The Lancet, no evidence of stunted growth or damage to immune system was substantiated. The Lancet paper's actual summary was:
Diets containing genetically modified (GM) potatoes expressing the lectin Galanthus nivalis agglutinin (GNA) had variable effects on different parts of the rat gastrointestinal tract. Some effects, such as the proliferation of the gastric mucosa, were mainly due to the expression of the GNA transgene. However, other parts of the construct or the genetic transformation (or both) could also have contributed to the overall biological effects of the GNA-GM potatoes, particularly on the small intestine and caecum.
The paper was accompanied by an editorial explanation for allowing the paper's publication (Genetically modified foods: "absurd" concern or welcome dialogue?), and an independent critique which had a contrary evaluation of the data: Adequacy of methods for testing the safety of genetically modified foods. This was followed by a lively follow up debate in several later issues of the journal.
Nonetheless, controversy about Pusztai's assertions still lingers, caused by strongly held but opposing views on his conclusions and data. On the one hand, there are claims of misrepresentation of Pusztai's results by Rowett Research Institute, but on the other hand, there are concerns by scientists about overstatement of the quality of his findings by non-governmental organizations, and emphasis on matters well removed from the actual laboratory observations which are rarely discussed in public debate, against the context well over one hundred other studies published by 2006 that support the safety of GM foods and feeds, and commentaries such as that of Nina Fedoroff .
Research protocols were sent by Pusztai to 24 independent scientists in different countries (including experts in physiology, medicine, toxic pathology, nutrition, microbiology and biochemistry). These disagree with the conclusions of the review committee and argued that his research was of good quality and justified his conclusions. Among 'casualties' in these events was Dr Andrew Chesson, vice chairman of European Commission scientific committee on animal nutrition and former top scientist at the Rowett Institute who was fired for publicly defending Pusztai's research.
Various reports concerning the politicisation of the peer review process and alleged deliberate misrepresentation of Pusztai's results were voiced by newspapers and some scientists.
Potentially dangerous corn
Another controversy recently arose around biotech company Monsanto's data on a 90-Day Rat Feeding Study on the MON863 strain of GM corn . In May 2005, critics of GM foods pointed to differences in kidney size and blood composition found in this study, suggesting that the observed differences raises questions about the regulatory concept of substantial equivalence
The raising of this issue prompted the European Food Safety Authority (EFSA) to reexamine the safety data on this strain of corn. The EFSA concluded that the observed small numerical decrease in rat kidney weights were not biologically meaningful, and the weights were well within the normal range of kidney weights for control animals. There were no corresponding microscopic findings in the relevant organ systems, and all blood chemistry and organ weight values fell within the "normal range of historical control values" for rats . In addition the EFSA review found that the statistical methods used by Séralini et al in the analysis of the data were incorrect . The European Committee has approved the ΜΟΝ863 corn for animal and human consumption.
Séralini et al have now completed a similar analysis of the NK603 strain of corn and have come to similar conclusions as they did in their previously discredited study.
A gene for an allergenic trait has been transferred unintentionally from the Brazil nut into genetically engineered soybeans while intending to improve soybean nutritional quality for animal feed use. Brazil nuts were already known to produce food allergies in certain people prior to this study. In 1993 Pioneer Hi-Bred International developed a soybean variety with an added gene from the Brazil nut. This trait increased the levels in the GM soybean of the natural essential amino acid methionine, a protein building block commonly added to poultry feed to improve effective protein quality. Investigation of the GM soybeans revealed that they produced immunological reactions with people suffering from Brazil nut allergy, and the explanation for this is that the methionine rich protein chosen by Pioneer Hi-Bred is the major source of Brazil nut allergy. Pioneer Hi-Bred discontinued further development of the GM soybean and disposed of all material related to the modified soybeans.
While this study indicates the possible risks of GM foods, and indeed any new food source, some point out it establishes the commitment the developmental community has toward consumer safety as well as the competence of current safeguards. Food allergy problems occur with many conventional foods, and Kiwi fruit, for instance, as a relatively new food in many communities, has become widely eaten despite provoking allergies in certain individuals.
Another allergy issue was published in November 2005, when a pest resistant field pea developed by the Australian CSIRO for use as a pasture crop was shown to cause an allergic reaction in mice.
Respected plant scientist Maarten J Chrispeels has made interesting comments about this example that illustrate how foods offer many different types of risks:
The recent Prescott et al paper in JFAC contains a very interesting study on the immunogenicity of amylase [starch digestion enzyme] inhibitor in its native form (isolated from beans) and expressed as a transgene in peas. First of all, amylase inhibitor is a food protein, but also a "toxic" protein because it inhibits our digestive amylases. This is one of the reasons you have to cook your beans! (The other toxic bean protein is phytohemagglutinin and it is much more toxic). This particular amylase inhibitor is found in the common bean (other species have other amylase inhibitors). Even though it is a food protein, it is unlikely ever to be used for genetic engineering of human foods because it inhibits our amylases. What the results show is that the protein, when synthesized in pea cotyledons has a different immunogenicity than when it is isolated from bean cotyledons (the native form). This is somewhat surprising but may be related to the presence of slightly different carbohydrate chains.
The immunologist who tested the pea noted that the episode illustrated the need for each new GM food to be very carefully evaluated for potential health effects.
Environmental and ecological impacts
As discussed above there is some evidence for positive impacts of the planting of GM crops on reduced greenhouse gas emissions and pesticide loads in the environment. However, there has been controversy over the results of a farm-scale trial in the United Kingdom comparing the impact of GM crops and conventional crops on farmland biodiversity. Some claimed that the results showed that GM crops had a significant negative impact on wildlife.
Others pointed out that the studies showed that using herbicide resistant GM crops allowed better weed control and that under such conditions there were fewer weeds and fewer weed seeds. This result was then extrapolated to suggest that GM crops would have significant impact on the wildlife that might rely on farm weeds. In July 2005 the same British scientists showed that transfer of a herbicide-resistance gene from GM oilseed rape to a wild cousin, charlock, and wild turnips was possible.
Many agricultural scientists and food policy specialists view GM crops as an important element in sustainable food security and environmental management. This point of view is summarized in the ABIC Manifesto:
On our planet, 18% of the land mass is used for agricultural production. This fraction cannot be increased substantially. It is absolutely essential that the yield per unit of land increases beyond current levels given that: The human population is still growing, and will reach about nine billion by 2040;70,000 km² of agricultural land (equivalent to 60% of the German agricultural area) are lost annually to growth of cities and other non-agricultural uses; Consumer diets in developing countries are increasingly changing from plant-based proteins to animal protein, a trend that requires a greater amount of crop-based feeds.
More skeptical scientists as Dr. Charles Benbrook point out that improvement of global food security is hardly being addressed by genetic research and that a lack of yield is often not caused by insufficient genetic resources.  Regarding the issues of intellectual property and patent law, an international report from the year 2000 states:
If the rights to these tools are strongly and universally enforced - and not extensively licensed or provided pro bono in the developing world - then the potential applications of GM technologies described previously are unlikely to benefit the less developed nations of the world for a long time (ie until after the restrictions conveyed by these rights have expired).
Research by the Pew Initiative on Food and Biotechnology has shown that in 2005 Americans' knowledge of genetically modified foods and animals continues to remain low, and their opinions reflect that they are particularly uncomfortable with animal cloning. The Pew survey also showed that despite continuing concerns about GM foods, American consumers do not support banning new uses of the technology, but rather seek an active role from regulators to ensure that new products are safe.
Only 2% of Britons are said to be "happy to eat GM foods", and more than half of Britons are against GM foods being available to the public, according to a 2003 study. 
Interestingly, about 550 Amish farmers in Pennsylvania have adopted GM crops, because they allow for less intensive farming (fewer pesticides, etc.), are more productive (under these specific conditions), and do not conflict with the Amish lifestyle.
Opponents of genetically modified food often refer to it as "Frankenfood", after Mary Shelley's character Frankenstein and the monster he creates, in her novel of the same name. The term was coined in 1992 by Paul Lewis, an English professor at Boston College who used the word in a letter he wrote to the New York Times in response to the decision of the US Food and Drug Administration to allow companies to market genetically modified food. The term "Frankenfood" has become a battle cry of the European side in the US-EU agricultural trade war.
The authors of The Frankenfood Myth provide some support for genetically modified food:
|This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Genetically_modified_food_controversies". A list of authors is available in Wikipedia.|