The Threats from Genetically Modified Foods

robin mather

• Robin Mather is a long-time food columnist and a senior associate editor at Mother Earth News; this article was published in the April–May 2012 issue. Mather has written about GM crops since the early 1990s, and is the author of A Garden of Unearthly Delights: Bioengineering and the Future of Food (1995), one of the first books on genetic modification written for the general public, and The Feast Nearby (2011).

Eighteen years after the first genetically modified food, the Flavr Savr tomato, came to market, the controversy about genetically modified foods rages. The call to label GM foods continues to build, yet the federal government has not responded. GM foods, illegal in many countries, have been part of the American diet for nearly two decades. As GMOs have come to dominate major agribusiness sectors, a handful of chemical/biotech companies now control not only genetically modified seeds but virtually our entire seed supply.“Genetic modification” refers to the manipulation of DNA by humans to change the essential makeup of plants and animals. The technology inserts genetic material from one species into another to give a crop or animal a new quality, such as the ability to produce a pesticide. These DNA transfers could never occur in nature and are not as precise as proponents make them sound.Some genetically modified crops have been engineered to include genetic material from BT (Bacillus thuringiensis), a natural bacterium found in soil. Inserting the Bt genes makes the plant itself produce bacterial toxins, thereby killing the insects that could destroy it. The first GM crop carrying Bt genes, potatoes, were approved in the United States in 1995. Today there are Bt versions of corn, potatoes and cotton.Roundup-Ready crops—soybeans, corn, canola, sugar beets, cotton, alfalfa and Kentucky bluegrass—have been manipulated to be resistant to glyphosate, the active ingredient in Monsanto’s broadleaf weed-killer Roundup.5   These two GM traits—herbicide resistance and pesticide production—are now pervasive in American agriculture. The

Department of Agriculture’s National Agricultural Statistics Service says that, in 2010, as much as 86 percent of corn, up to 90 percent of all soybeans and nearly 93 percent of cotton were GM varieties.You’re eating genetically modified foods almost daily unless you grow all of your food or always buy organic. Federal organic standards passed in 2000 specifically prohibit GM ingredients. Other genetically modified crops—none labeled—now include sweet corn, peppers, squash and zucchini, rice, sugar cane, rapeseed (used to make canola oil), flax, chicory, peas and papaya. About a quarter of the milk in the United States comes from cows injected with a GM hormone, honey comes from bees working GM crops, and some vitamins include GM ingredients.

Some sources conservatively estimate that 60 percent or more of processed foods available in the United States contain GM ingredients, because most processed foods contain corn and/or soy products.Genetically modified foods are not labeled in the United States because the biotech industry has convinced the Food and Drug Administration (FDA) that GM crops are “not substantially different” from conventional varieties. The FDA, however, does no independent testing for human or animal safety and relies strictly on the research conducted by the manufacturers of the products. The main GM producer, Monsanto, makes it nearly impossible for independent scientists to obtain GM seeds to study. Meanwhile, many countries require labeling (the European Union, Australia), and some have even banned all GM foods (Japan, Ireland, Egypt).Genetic modification technology does have extraordinary potential. In the practice known as “pharming,” animals are genetically modified to give milk, meat or blood from which medicines are manufactured, as when GM goats produce milk containing a blood-thinning drug called ATryn. Research laboratories use GM mice to seek cures for diseases. Yet with minimal oversight on the crops and livestock produced, many people have serious worries about GMO technology. Many of us simply want the right to know what is in our food.

Bt Crops: Is Built-In Pesticide a Boon or Bane?

Monsanto has led the invasion of Bt crops, starting with corn, cotton and potatoes. Syngenta has developed Bt corn as well, as have Bayer, Dupont and other companies. Such crops are marketed to growers as pest-resistant.10   Some researchers have concerns about the effect of Bt crops on human health. Professor Emeritus Joe Cummins of the University of Western Ontario told the U.S. Environmental Protection Agency (EPA) that “there is evidence that [Bt] will impact directly on human health through damage to the ileum [the final portion of the small intestine, which joins it to the large intestine] … [which] can produce chronic illnesses such as fecal incontinence and/or flu-like upsets of the digestive system.”Bt may also harm beneficial insects such as honeybees and lady beetles.