Three questions for biologist Lisa Weasel on GMOs (Genetically Modified Organisms)
In 1996, U.S. farmers planted the first commercial genetically modified (GM) seeds. Some were engineered to resist herbicides so farmers could apply weed-killing herbicides without destroying their crops. Others contained genes to keep pest insects at bay. Today, about 92 percent of all soy and 80 percent of all corn grown in the U.S. is GM. These crops feed the animals that feed us, and they provide the bulk of our sweeteners and cooking oil. In fact, more than 70 percent of processed foods sold in the United States have ingredients from GM crops.
Yet GM crops remain controversial. France, Italy, Japan and several other countries have banned them because of health concerns and worries that GM crops may spread their engineered traits to other plants. Although company-funded studies and the FDA have labeled these foods as safe, a few preliminary studies suggest they are responsible for allergies, decreased fertility and super-weeds. “Genetically modified foods are a very misunderstood issue in this country,” says Lisa Weasel, a biologist at Portland State University and a member of Oregon’s task force on developing policy for biopharmaceutical crops. Her latest book, Food Fray: Inside the Controversy over Genetically Modified Foods (AMACOM, 2009), takes readers to the frontlines of the debate.
What are your concerns about GM food crops and human health?
There are too many unknowns. There aren’t enough studies really documenting that they are safe. The safety data is all generated by the companies and submitted to our government. We have lots of reasons as consumers to ask for independent safety studies. GM ingredients are largely found in processed food—except for papayas, which in this country tend to be GM varieties. The only way to be certain you are not eating GM foods is to buy certified organic, which must be 95 percent GM-free.
Are GM crops affecting the health of other plants and the environment?
If there are closely related species in the wild or in nearby crops, then pollen from a GM crop can pollinate another plant, thereby spreading its genetically engineered traits. There’s been research, for example, documenting the spread of transgenic corn genes into native corn species in Mexico. This is particularly troubling because many native and wild relatives of corn grow in Mexico and such cross-pollination could threaten the genetic biodiversity of corn, an important food crop around the world. Here in the U.S., organic farmers have filed a lawsuit against the USDA for allowing the planting of GM sugar beets, because the GM traits could potentially spread into closely related organic crops, such as chard and table beets, voiding their organic status. Another environmental issue is the increase in chemical use. Between 1994 and 2005 there was a 15-fold increase in the use of Roundup, an herbicide produced by Monsanto—which is also the world’s leading producer of GM seeds. About 80 percent of GM crops are herbicide-tolerant, so farmers can use far more herbicides on their crops and not kill them. If you’re going to engineer a crop to resist a weed-killer that just invites the use of herbicides.
Are there any examples of GM crops promising health benefits?
Golden rice is a strain of rice genetically engineered to contain beta carotene in the endosperm. (Your body converts beta carotene to vitamin A.) Golden rice was originally developed over 10 years ago with a humanitarian mission in mind to treat vitamin A deficiency, however regulatory and patent issues as well as consumer opposition in developing countries have kept it out of the food supply to date.