As the world population continues to grow, the task of feeding these populations too often fails. Excessive heat, drought, crop destruction by pests, salinized irrigation water, and excessive poverty form some of the most common reasons for such failure. The most prevalent solution to this problem has thus far been the development and use of crops that have been given some degree of immunity to these issues through genetic modification (GM). The benefits of GM crops, however, must be weighed with the dangers they pose. GM crops pose health risks, force the advancing of pest populations that are highly resistant to pest control measures, eliminates non-GM crops through cross pollination, and are financially prohibitive for developing nations. Thus, GM crops fail to deliver the solution they promised to create.
In the United States, one of the largest producers of GM crops, the process of determining end-user safety of GM crops involves comparing modified proteins in the GM plant with same protein of an unmodified plant. A typical example of this process is found in the ongoing safety evaluation of soybeans being conducted by the US Department of Agriculture (USDA)(2007), which states, “Proteins will be extracted from seeds using the modified TCA/acetone method and separated using 2D-PAGE, analyzed using image analysis and in those cases when unique protein spots appear in any treatment, further characterization using MALDI-TOF-MS will be undertaken.” Under such conditions, it is assumed that if the protein looks identical, it will behave identically when ingested, and although that may be true in some cases, no one is certain it is universally true. As Dr. Margaret Mellon (2007), director of the agricultural and biotechnology program at the Union of Concerned Scientists, said:
“Lots and lots of people -- virtually the entire population -- could be exposed to genetically engineered foods, and yet we have only a handful of studies in the peer-reviewed literature addressing their safety. The question is, do we assume the technology is safe based on an argument that it's just a minor extension of traditional breeding, or do we prove it? The scientist in me wants to prove it's safe (PBS, 2007).”
Opinions regarding the safety of GM crops tend to be strong on both sides of the argument, and because of the polarization of opinion, proof of GM crop safety is necessary. Despite the regulatory acceptance of the current protein isolation technique for determining crop safety, it has one significant flaw, the fact that even when a protein appears chemically identical, it can behave very differently when ingested by a test subject. A team of scientists working for the Division of Molecular Bioscience at the Australian National University in Australia discovered while testing a GM pea they had developed to be resistant to the Pea Weevil. By isolating a gene in a common bean that disrupted the reproductive ability of the Pea Weevil and splicing that gene into the pea, they were able to successfully create a pea that was resistant to the Pea Weevil. During the safety testing, they found that the transgenic protein in the GM pea was chemically identical to the one in the common bean. This is as far as most accepted safety testing of GM crops would go. However, this team went further and fed the GM pea to test mice. During this testing, they found that the protein behaved very different once ingested, and the mice fed the GM pea developed serious allergies and other significant health problems. As a result of these finding the pea weevil resistant pea project was discontinued (Prescott et al., 2005). This case creates enough doubt on the effectiveness of current safety testing practices to warrant retarding the widespread implementation of GM crops, proving more testing is required before GM crops can be considered safe for consumption.
Because current testing procedures fail to adequately determine the safety of GM crops, the risk of cross-pollination with non-GM crops must be addressed. According to a study on GM cross-pollination done by Drs. Markus Schmidt and Gurling Bothma, of the University of Vienna (2006), areas that have historically been used for traditional farming tend to hold significant genetic diversity. This diversity is essential to protect against changes in various diseases and pests that threaten these crops (Pg. 1). By holding many combinations of genetic data in the natural crop selections, the likelihood that a pest of disease will destroy the entire crop population is slightly decreased. According to the Schmidt-Bothma study on gene flow within sorghum crops and related weeds in central Africa, it was discovered that no barrier existed to prevent the flow of genetic material between fields of crop and surrounding weeds (pg. 2). The study concluded that:
“The outcome of this study shows that gene flow in sorghum will take place, and introgression of transgenic characteristics into crops and wild relatives in likely. Some of the novel characteristics (e.g., pest, disease, and drought resistance) envisioned for future transgenic development could favor the survival of hybrids with crop wild relatives outside the agroecosystem (Smith and Frederickson, 2000; deVries and Toenniessen, 2001). Further research should therefore also focus on the prevention of gene flow from transgenic sorghum to other sorghum crops, landraces, and wild relatives before hand, e.g. by using adequate buffer zones and the possibilities (and limitations) of cytoplasmic male sterility (Schmidt, Bothma. pg. 8).”
Once a transgenic trait offering resistance to pests is introduced into a population, natural selection gives favor to the plants possessing that trait. As a result, the genetic diversity diminishes. The genetic diversity that allows some plants to possess genes that give it natural resistance to pests, but because there are still plants that are susceptible to pests, the populations of pests that are resistant to either GM or natural pesticides are not favored. Without genetic diversity, there is a problem when one examines pest populations using the basic principles of natural selection. If a GM crop is developed and deployed that has a resistance to a pest, then the majority of those pests will die off, while those that survive have a genetic trait allowing them to be unaffected by the GM trait. As the pest population increases, each subsequent generation will favor those with a stronger immunity to the GM trait, thus rendering the trait ineffective against the pest. Because the GM trait was initially favored, the genetic diversity is likely to have been diminished through cross-pollination, so as the new genetically superior pest increases in population, the crops, which now all carry the same genetic profile, will be destroyed. The only way to avoid the destruction of genetic diversity is to inhibit the ability of the GM crop to reproduce with either natural crops or wild relatives. There are two ways this can be accomplished, first is the isolation of GM crops, and second is the development of GM seeds that are sterile, and thereby cannot reproduce. Both of these solutions create some difficulty for developing nations, and neither can prevent the increase in GM-resistant pests.
Within most developing nations, where the need for affordable food is the direst, quality farmland can be rare, and all but the most meager lots are far too expensive for the majority of the populations, as Dr. Peter Rosset, an agricultural ecologist and the executive director of Food First/The Institute for Food and Development Policy, being quoted at www.globalissues.org points out:
“First, where farmland is bought and sold like any other commodity and society allows the unlimited accumulation of farmland by a few, superfarms replace family farms and all of society suffers.
Second, where the main producers of food - small farmers and farm workers - lack bargaining power relative to suppliers of farm inputs and food marketers, producers get a shrinking share of the rewards from farming.
Third, where dominant technology destroys the very basis for future production, by degrading the soil and generating pest and weed problems, it becomes increasingly difficult and costly to sustain yields. (Rosset, n.d.).”
With the rise of such “superfarms,” the subsistence farm becomes more difficult for the most needy to obtain, and when it is obtained, it is virtually impossible to adequately isolate natural crops from GM crops, thus destroying the genetic diversity of the region and making reliance on segregation to prevent such destruction non-viable.
As an alternative to relying on crop segregation to protect genetic diversity, some producers of GM crops are developing plants with sterile seeds. As Wendy Hollingsworth, Science, Technology and Innovation Specialist at the Inter-American Institute for Cooperation on Agriculture (IICA) in Barbados (n.d.) explains:
“Terminator genes prevent crops from producing fertile seed, this means that farmers growing these crops would have to buy new seed each year rather than saving part of the harvest to plant the next years (sic) crops. The terminator technology from a scientific perspective is a brilliant development of the creative process. However, where the technology runs off course is in its application. Proponents of the technology argue that it would be a useful method of preventing infringement on any patent rights or plant breeder's rights granted and could also be used to minimize environmental risks of GM crops (Hollingsworth, n.d.).”
In terms of preventing cross-pollination and negating environmental impacts on genetic diversity, such “terminator technology” works very well, although it will not inhibit the advancement of GM-resistant pests. The fundamental flaw with this technology is that the farmers who would be in the greatest need of such crops are the poorest farmers in the world. By requiring the purchasing of new seed every season, control of food supplies is taken away from farmers and placed in the corporations that produce the GM seeds (Hollingsworth, n.d.). As prices increase, and the ability of poor farmers to buy seed diminishes, starvation increases and the ability of developing nations to create sustainable and independent food supplies is destroyed.
When the financial conditions in the developing world are viewed in context with food supplies, it becomes clear that the solution to world hunger proposed by the widespread use of GM crops is neither effective nor financially viable. It can be argued that monetary limitation, not inadequate food supplies, are the principle cause of widespread hunger as Dr. Rosset (2007) explained:
. . . [M]ountains of additional food could not eliminate hunger, as hunger in America should never let us forget. The alternative is to create a viable and productive small farm agriculture using the principles of agroecology. That is the only model with the potential to end rural poverty, feed everyone, and protect the environment and the productivity of the land for future generations (Rosset, 2007).
In light of the observation that the cause of world hunger has far less to do with the food supply and more to do with socio-economic conditions in the developing world, the proliferation of GM crops is not as optimal of a solution as initially thought. With the effectiveness of current safety testing procedures having been proved inadequate, and the fact that no good solutions to prevent cross-pollination exist, any benefit that may be gained from the widespread use of GM crops pales in comparison to the risks. There are no valid reasons for the widespread use of GM crops.
References
USDA (n.d.). Evaluation of the quality and safety of transgenic soybeans. Retrieved November 10, 2007, from http://www.ars.usda.gov/research/projects/projects.htm?accn_no=410447
PBS (2007). Harvest of Fear. Retrieved November 10, 2007 from http://www.pbs.org/wgbh/harvest/exist/arguments.html
Prescott et al. (2005). Transgenic Expression of Bean a-Amylase Inhibitor in Peas Results in Altered Structure and Immunogenicity. Agriculture and Food Chemistry, 53, 9023-9030.
Schmidt, M., & Bothma, G. (March-April 2006). Risk assessment for transgenic sorghum in Africa: crop-to-crop gene flow in Sorghum bicolor (L.) moench. Crop Science, 46, 2. p.790(9). Retrieved November 10, 2007, from Academic OneFile via Gale:
http://find.galegroup.com.ezproxy.umuc.edu/itx/start.do?prodId=AONE
Rosset, P. (n.d.). If Biotech Industry Is Serious About Solving World Hunger, It Is Poorly Attacking Symptoms Only. Retrieved November 10, 2007 from http://www.globalissues.org/EnvIssues/GEFood/Hunger.asp.
Hollingsworth, W. (n.d.). Intellectual Property Right and Genetically Modified Organism. Retrieved November 10, 2007 from http://www.consumer.gov.tt/link/link7-8.htm
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