Genetically Modified Crops
For centuries, farmers have bred crops for certain desirable traits. Genetic engineering provides a quicker and more precise way to achieve the same goal, in one generation rather than twenty. Genetically Modified (GM) crops offer improved yields, enhanced nutritional value, longer shelf life, and resistance to drought, frost, or insect pests. Examples of GM crops include corn varieties containing a gene for a bacterial pesticide that kills larval pests, and soybeans with an inserted gene that renders them resistant to weed-killers such as Roundup. “Nutritionally enhanced” GM crops under development include varieties of wheat free of gluten, a major cause of food allergy; vegetables with higher vitamin E content to help fight heart disease; and “golden rice” genetically engineered to contain vitamin A and iron so as to prevent common nutritional deficiencies in developing countries. In the United States, GM corn is used in many common foods, including cornmeal, tortilla chips, and high-fructose corn syrup (a sweetener in soft drinks and baked goods). In 2010, more than 80 percent of U.S. corn, soybeans, cotton, and sugar beets were GM varieties. Whereas U.S. regulation of GM foods is based on the product, European Union (EU) regulations are based on the process. As a result, the EU regulates GM plants and animals more stringently, and European publics are wary of genetically engineered foods. Internationally, the cultivation of GM crops has grown from six countries in 1996 to 25 countries in 2009, and it is expected to reach 40 countries (mostly in the developing world) by 2015. In 2009, approximately 134 million hectares of land were under GM crop cultivation.
In addition to potential food safety risks, critics of GM crops have raised concerns about their potential adverse ecological effects.
First, if GM crops cross-breed with wild relatives, the foreign transgenes could “contaminate” the natural ecosystem. For example, pollen from Bt-corn has been known to fertilize non-Bt crops. Such genetic contamination can pose problems for certified producers of organic produce, as well as certain U.S. trading partners.
Second, some ecologists have warned about the harmful effects of Bt corn on non-target insects, such as Monarch butterflies that feed on wild milkweed growing near cornfields.3 To date, these fears have not materialized. However, research over a longer time period is needed.