Genetically modified foods: benefits, risks, and applications

History Of Genetically Modified Foods

Genetic Processes Used in Making Genetically Modified Foods

Scientific Studies to Date

Positive and Negative Arguments

Genetically Modified Foods

Today, the Earth is home to almost seven billion hungry humans, and the so-called "green revolution" of the mid-20th century has virtually reached its maximum production limits using the agricultural technologies introduced at the time. Moreover, the world's population continues to grow rapidly, particularly in those parts of the globe where farmers in undeveloped countries are unable to afford the relatively expensive and energy-intensive techniques used in more efficient, large-scale agricultural operations. In this environment, it would seem that scientists and the general public alike would welcome any innovations in agricultural technology that promised to provide more food for the world, but there have been mixed reviews of the use of genetically modified foods in recent years that continues to restrict their use. This paper provides a review of the relevant literature to deliver a background and overview of genetically modified foods and their history, the genetic processes that are typically used in making genetically modified foods, a representative sampling of the scientific studies conducted to date and positive and negative arguments concerning their use. A summary of the research and important findings are presented in the conclusion.

Background and Overview

In 1968, Paul R. Ehrlich's book, The Population Bomb, predicted a global famine based on the exponential growth in the world's population that could not be matched by existing agricultural techniques. Fortunately, although the time bomb described by Ehrlich failed to materialize in substantive ways due in large part based on the agricultural innovations introduced as part of the green revolution, these technologies have reached their maximum production capabilities in recent years and many undeveloped countries are not able to afford the techniques used. In this regard, Dhanagare emphasizes that in countries such as India, "The green revolution was not really taking place, that the new agricultural technology was accessible only to the large-scale farmers, and the prosperity unleashed by the green revolution was distributed differentially to the various categories of farmers, putting the small-scale and marginal farmers at a relative disadvantage" (3).

From this perspective, then, the revolutionary aspects of the green revolution were limited to those countries that could afford the investment in the supporting technologies in the first place, constraints that were particularly applicable to developing nations with large populations to feed. In this regard, Dhanagare concludes that, "The reasons for differential distribution were obvious. The high-cost, high-yield cereal technology of the green revolution called for substantial capital investments generally beyond the means of the majority of small-scale and marginal farmers" (1998:3). In reality, though, the green revolution was just part of the ongoing efforts to help feed a hungry world and food crops have been modified in one form or another since antiquity for help provide improved yields and to promote desirable qualities, and these issues are discussed further below.

History of Genetically Modified Foods

Farmers have crossbred plants and animals for centuries in an effort to promote desirable characteristics in succeeding generations, but the application of scientific approaches involving genetic modifications are much more recent. The science has improved to the point where inter- and intra-species manipulation of genetic material can be used to create desired product characteristics such as resistance to specific diseases, tolerance to agricultural chemicals or enhanced nutritional profiles (Brady and Brady 2003). Prior to the introduction of genetic engineering techniques, gene modification in plants and animals was accomplished through breeding. In this regard, Jefferson (2006) reports that, "The traditional breeding method ultimately produces the same desired effect as genetic engineering, but it occurs over a much longer time span and is self-limiting. Selected individual genes are transferred from one organism to another between plants and between animals, but not between plants and animals" (34). By using genetic engineering methods, though, it is possible to transfer genes between any living organisms, even between plants and animals: For instance, Jefferson cites the hypothetical example of inserting a gene from a fish that lives in cold seas into a strain of strawberry so that the strawberry could better endure extremely cold conditions and even frost. According to Brady and Brady, "Crops developed using genetic modifications were first made available commercially in 1996" (Brady and Brady 2003:13).

As to the first commercially grown genetically modified food crop, Chapman reports that this was a tomato that was developed by California company in the 1990s called the FlavrSavr. The FlavrSavr was genetically modified in order to provide the crop with a longer shelf life and retard ripening during transportation (Chapman 2006:1). In Europe, a variety of this tomato was employed in the manufacture of tomato puree; however, the resulting controversy that occurred among European consumers concerning the science used to create genetically modified foods that were being marketed in Europe halted the use of this and other such altered foods (Chapman 2003). As a result, the vast majority of genetically modified crops are grown, marketed and consumed in the United States. According to Brady and Brady, "Three fourths of genetically modified crops grown in the world are planted in the U.S. In 2001, 69% of cotton, 68% of soybeans, 55% of canola, and 26% of corn grown in the U.S. was genetically engineered. Other genetically engineered crops that are available but not widely adopted included sugar beets, potatoes, and sweet corn" (Brady and Brady 2003:13). The respective amounts of genetically modified food crops are illustrated in Figure 1 below.

Figure 1. Percentage of Genetically Modified Foods Grown in the U.S. As of 2001

Source: Brady and Brady 2003

As noted above, consumers in other countries, particularly those in the European Union, are wary of these and other genetically modified foods for reasons that may be related more to a misunderstanding concerning how these techniques are used and what is involved, and these issues are discussed further below.

Genetic Processes Used in Making Genetically Modified Foods

According to Brady and Brady (2003), genetically modified or genetically engineered food crops are those that have had their genetic composition altered in some way in order to promote a desirable characteristic or to retard undesirable characteristics. These authors add that, "The modification might involve importing genetic material from one plant or animal to another, rearrangement of genetic material within a plant or animal, or removal of genetic material from a plant or animal. Modifications can result in an almost infinite variety of genetic combinations" (Brady and Brady 2003:13). While most American consumers routinely consume foods that have been genetically modified with no effect, there is a growing body of research concerning the safety of these techniques that indicate there are some risks involved, and these issues are discussed further below.

Scientific Studies to Date

Interestingly, more research has been conducted to date concerning consumer acceptance of genetically modified foods than has been devoted to just how safe these products might be when consumed by humans. The few studies of the latter type that have been conducted include a study by Dr. Arpad Pusztai of the Rowett Research Institute in Aberdeen, who conducted a feeding trials study in 1998 that indicated that a strain of potatoes that had been genetically modified using an insecticide gene were toxic to rats (Chapman 2006). In addition, researchers at the U.S. Environmental Protection Agency (EPA) have determined that some genetically modified corn products have the potential of producing allergic reactions in humans (Barrett 2002). In late 2000, a growing number of reports were received by the EPA concerning genetically modified corn that had not been approved for human consumption was identified in a variety of food products, including taco shells, corn chips and other corn products; the strain of corn known as "Starlink" had been bioengineered using a toxin from bacteria that permits corn plants to ward off attacks by natural insect pests (Barrett 2002). Based on an earlier study by the EPA that determined the protein in Starlink was not readily broken down in humans, it was approved for use in animal feeds but prohibited for use in food products intended for human consumption (Barrett 2002). According to this author, "Despite this regulatory restriction, Starlink corn found its way to grocery store shelves and restaurant tables. Dozens of people reported allergic or other adverse reactions" (Barrett 2002:29). A subsequent study by Kalaitzandonakes, Marks, and Vickner (2004) determined that the extensive media coverage of the Starlink corn incident in the United States resulted in a statistically significant decline in consumer demand for taco shells among American consumers.

Research has also shown that there is a danger of cross-contamination of legacy crops with genetically modified strains as shown by a study conducted in September 1999 that found that pollen from a genetically modified oilseed rape that had been cultivated at a trial site in Oxfordshire was contained in beehives located almost 3 miles distance (Chapman 2006). According to this authority, "The research was carried out by experts at the Britain's National Pollen Research Unit. Then in May 2000, honey on sale in supermarkets was found to be contaminated with GM pollen from British crop trials. Two out of nine samples show contamination" (Chapman 2006:5). The results of an analysis by Fox (1999) confirmed this cross-contamination of pollen: "The pollen produced by these plants, carrying new genes, cannot be contained. As a result, genetic pollution of natural crop varieties and of wild plant relatives may occur. Unlike other forms of pollution, genetic pollution is uncontrollable, irreversible, and permanent, posing a major threat to biodiversity and to the bio-integrity of the entire life community" (Fox 1999:37). Despite the findings of these studies, in 2000, the National Research Council emphasized that based on its research, it was unable to identify "any evidence suggesting that foods on the market today are unsafe to eat as a result of genetic modification" (quoted in Wooster 2001 at 58).

Moreover, Morse notes that even the findings reported in the aforementioned study by Pusztai were dubious at best. "The few studies claiming genetically modified food is harmful are highly controversial," Morse points out and adds, "For example, in 1999 The Lancet published a study by Arpad Pusztai claiming that some people who ate genetically modified potatoes suffered organ damage" (2001:58). More importantly, this author emphasizes that, "The Lancet also published a critique stating that Pusztai's experiments were 'incomplete, included too few animals per diet group, and lacked controls' and thus 'do not allow the conclusion' the potatoes were dangerous. Pusztai was then sacked for publicizing research which hadn't been peer-reviewed" (quoted in Wooster 2001 at 58).

Yet another study sponsored by the UK government determined that 90% of British consumers were adamant about refusing to consume products that contained genetically modified components until there were further studies conducted to ensure that these techniques were safe (Chapman 2006). Likewise, Huffman, Shogren, Rousu and Tegene (2003) report the results of a telemarketing survey conducted in February 1999 in New Haven, Connecticut that found that an overwhelming majority of the respondents (82%) surveyed strongly believed that genetically modified foods should be so labeled, a finding these researchers note is congruent with a majority of the surveys concerning genetically modified foods that have been conducted to date.

Positive and Negative Arguments Concerning Genetically Modified Foods

Although there are some compelling arguments against the use of genetically modified food crops unless and until scientists can guarantee their safety, there are some equally compelling arguments in support of their use today. For example, according to Jefferson (2006), "With an ever-increasing global population, hunger in the developing world, and the health risks of pesticides, some experts view genetically modified food as a panacea. Others view it as one of the most serious threats to human civilization" (33). Advocates of genetically modified foods maintain that the use of these technologies can help produce food products that have a superior appearance and taste, remain fresher longer, and contain more nutrients than their unaltered counterparts (Brady and Brady 2003). Although there are some concerns that genetically modified foods crops hold the potential to harm the environment in some ways (some of which remain strictly conjectural), proponents of the technology emphasize that these techniques can actually benefit the environment because they reduce the needs for harmful pesticides and require less chemical fertilizers (Jefferson 2006). According to Brady and Brady, "Such technology can produce crops that are resistant to diseases and pests and may yield food components that require less processing. Applications of genetic modification allow farmers to produce more and better crops using less time and fewer chemical fertilizers, pesticides, and herbicides" (13). The bottom line for genetically modified food proponents, then, relates to the fact that these technologies will provide consumers with better foods at lower prices than in years past (Brady and Brady 2003).

By contrast, critics of genetically modified foods maintain that these foods represent an unknown health risk to consumers especially since they have the potential of containing allergens not traditionally identified with a food. In addition, critics argue that genetically modified crops hold the potential for harming the ecology of a region and that there are ethical issues involved when a plant or animal's genetic material is purposely modified for whatever reason. Furthermore, some critics of genetically modified food crops cite the same reasons the green revolution has not been achieved by underdeveloped nations based on the economic consequences of genetic modification given that these countries do not enjoy the same access to technology as their developed counterparts and that some corporations could use access to the genetic modification technologies in an effort to control the food markets (Brady and Brady 2003). Likewise, Jefferson (2006) notes that, "Opponents [of genetically modified foods] argue that government agencies are violating their religious and consumer rights" (34).

Despite the common uses of genetically modified food crops in the United States, many consumers in America remain either unaware of their widespread use or do not know what scientific processes are used to alter these food crops; in fact, the Food and Drug Administration (FDA) currently requires that genetically modified foods be labeled or feature labels that indicate the food has been modified only if one of the following conditions exists: