Genetically modified organisms have been in American fields and grocery stores for more than a decade, but the controversy surrounding them is as fresh as ever. One Cornell University scientist says that in the discussion about GMOs, emphasizing the scientific facts is key -- but she also cautioned against arrogance on the part of genetic engineering advocates.
“Food is very intimate to people, and dismissing their concerns is not a wise strategy,” plant scientist Margaret Smith said at an Inside Cornell event with reporters in New York in Friday.
As with any new technology, in GMO research there are unknowns to be studied, and potential risks to be evaluated. But with GMOs, that evaluation takes place in the midst of an extremely polarized public debate.
Smith works with traditional methods of plant breeding in her own research on corn, but can often be found teaching classes and speaking in public on the science of GMOs. It’s a hefty job -- misconceptions abound, she says. Some of the more high-profile studies purporting to show that GMOs are harmful – a study released in September 2012 that drew a link between GE corn and tumor development in rats, and a recently released paper claiming that GE corn and soy feed caused stomach inflammation in pigs – have been criticized as flawed by many other scientists.
“There needs to be much better [studies], more well-done [studies,]” Smith said.
At the moment, the scientific consensus is that the genetically engineered foods on the market don't pose any serious health risk. Currently, the commercially available genetically engineered crops in the U.S. are insect-resistant corn and cotton; herbicide-resistant soybeans, canola, cotton, corn and alfalfa; and virus-resistant papaya and squash. Other GE crops are on the horizon. A new kind of drought-tolerant corn was planted in experimental fields last spring (eerily timed, since the Midwest had a record drought in 2012).
Despite the fact that they all get frequently lumped together, not all GMOs are built alike. Insect-resistant crops contain a gene from a bacterium that codes for a biological pesticide. Monsanto’s Roundup Ready crops get their resistance to the herbicide glyphosate from an enzyme taken from another kind of bacteria. A GE potato made by the J.R. Simplot Company that’s under consideration for deregulation by the U.S. Department of Agriculture has been tweaked to rid the potato of a neurotoxin and potential carcinogen called acrylamide, which is widely found in non-GE potatoes. But in the Simplot potato, the genetic engineering technique, called RNA interference, uses genetic material from the potato itself, not another organism.
“As new products come through the pipeline, we will need to look at each on a case by case basis,” Smith said.
With respect to GMOs’ impact on the environment, the verdict is mixed. A 2010 study from the National Council on Research found that the adoption of Roundup Ready crops led to farmers using more herbicides; however, they’re not using the especially toxic herbicides as much anymore. And farmers are using less insecticides overall.
There's the looming worry of “superweeds” and “superbugs” that could arise in the wake of GMO adoption, much in the same way antibiotic use in humans and livestock has led to antibiotic-resistant strains of bacteria. Smith says this is a problem that won’t go away on its own.
“If you try to control a problematic pest with the same control measures over and over, very rarely does that pest disappear from the face of the earth; it evolves,” Smith said.
Unless mitigation efforts are put in place – like farmers rotating between different kinds of herbicide, trying to engineer new crops that use different strategies to resist the effects of herbicide or kill insects, the genetically modified advantages of GMOs will be negated. Farmers would lose a very strong tool, Smith says.
Environmentalists also worry about GE crops escaping into the wild, or contaminating other farms – as seen in the recent appearance of experimental GE wheat in a field in Oregon. (Monsanto experimented with GE wheat years ago, but eventually abandoned the project). At present, a USDA investigation has not found evidence of GE wheat in the surrounding area, and it’s still something of a mystery as to how the GE wheat got to that particular field.
There are risks of GE crop escape at many stages in the plant’s life cycle – wind-blown pollen, a bird or mouse passing a seed in the right place, or a mixup at the farm or feedlot. But there is still no concrete evidence that GE corn and soy will pose as much of a threat to wild ecosystems as, say, an invasive species.
“Most of our cultivated crops are notoriously awful at competing in the wild,” Smith says.
There are ways to improve the current GMO regulatory scheme that could alleviate public concern, Smith says. One thing that worries many is the fact that unless a GE crop contains a totally novel compound or element, a company is only encouraged to have a food safety consultation with the U.S. Food and Drug Administration, not required.
“Why not at least have mandatory consultations?” Smith said. “It would make the anxiety less, and serve well the credibility of the regulatory agencies, so it’s not just industry saying ‘oh it’s fine.’”
Roxanne has liked science ever since she started watching "Bill Nye the Science Guy" on Saturday mornings over a bowl of sucrotic O's. She especially likes writing about...