Two recent items in The Durango Herald called into question the safety of crops from seeds that have been modified by rearranging their genes or introducing new genes into the seeds in order to improve the quality and quantity of the product. One was an opinion piece by Lyn Patrick a naturopathic practitioner headlined Genetically modified crops, safety asserted, but far from proved (Herald, Nov. 18), and the other was a front page news story headlined GMO foes want you to say no (Herald, Dec. 13).
Genetic modification (GM) technology improves on the traditional methods of cross breading by having more control over the process and thus being more predictable. It also involves a higher risk because of the wider variety of genes that can be combined in one product. Scientists working in the GM field are well aware of the risks, believe they can be controlled and that they are minor compared with the enormous potential the technology has for improving farming (growing more crops on less land using less water and fertilizers.) The scientific community agrees with that assessment as reported by the National Academy of Sciences (Biological Confinement of Genetically Engineered Organisms, National Academy Press, 2004)
As with any new technology, questions are always raised about its safety, and opponents like Patrick try to convince the public that the GM products are dangerous to people, animals and the environment and should be banned. And if not banned, the products should be labeled so that people can avoid eating the produce.
I have written several articles about this topic over the years, and I have no delusion that I can change dedicated opponents minds. These people view GM as ideologically or monetarily threatening, coupled with a distorted understanding of risk assessment.
Such attitudes are not easily swayed by scientific evidence. But, by discussing the questionable arguments those opposed are making, perhaps I can assure some who are on the fence that the assessment of the scientific community is correct. Let me address the safety issue first.
The best answer I can provide in a short column is a scientific reference written for popular reading: Pamela Ronalds recent book Tomorrows Table: Organic Farming, Genetics and the Future of Food.
Ronald is professor of plant pathology at the University of California, Davis, and addresses questions skeptics have raised such as: Is GM food risky to eat? What about weeds, gene flow and the environment? Who owns the seed and who owns the genes? The answers she provides using scientific documented evidence should reassure anyone with an open mind that the benefit to risk ratio for this technology is overwhelmingly positive.
In addition to the controlled experimental results Ronald references, there is also compelling epidemiological evidence that the produce is safe. Between 70 and 80 percent of processed foods in the U.S. over the last two decades have contained some GM products, yet according to the U.S. Food and Drug Administration and the Centers for Disease Control and Prevention, no instance of harm to human health has been detected resulting from commercialization of GM crops.
The Dec. 13 news story, which was notably short on scientific evidence, claimed the opposition to GM crops is growing when the opposite is true. One telling example is that the European Food Safety Authority in this years annual conference ruled that based on strict adherence to empirical evidence, GM products pose no health risk (Science, Nov. 30). Until recently, Europe has been a bastion of opposition to GM technology.
Of course as with any technology, science can never demonstrate that GM products are risk free under all possible conditions, for the simple reason that it is impractical to test all possible conditions. As a result, even though a large number of scientific studies have uncovered no harm that cannot be avoided, opponents insist that the technology be banned because not enough conditions have been tested without specifying what they would consider to be enough.
Patrick uses this absurd reasoning, as do all the opponents interviewed in the Herald news story. More important, these arguments leave out any consideration of benefits. When benefits are included, it shows that a ban would deprive society of a technology that would confer much greater net benefits than risks.
The second demand by opponents that all foods that contain GM products be labeled seems simple enough. But studies show that in order to be accurate about contents, the U.S. food wholesale and delivery system would have to be duplicated at tremendous expense.
Everyone, including those who are not concerned about the issue, and particularly the poor, would have to share the increased food costs. Patrick justifies the need by claiming, more than 90 percent of Americans are in favor of GMO labeling a number seemingly pulled out of thin air. Otherwise, how is it that California rejected a proposal for mandatory labeling in the November election by 53 percent?
Garth Buchanan holds a doctorate in applied science and has 35 years of experience in operations research. Reach him at firstname.lastname@example.org.