By Bradley J. Fikes
February 8, 2005
Sides Argue Whether Genetically Engineered Crops Harm Human Health And The Environment
Corn, soybeans, yellow squash, pasta and cottonseed oil: The number of foods made with genetic engineering keeps growing. They are found in supermarkets across the country. But the everyday coupon-clipper would be hard-pressed to identify which are the genetically engineered, or GE, foods ---- or what benefits they give.
Early forecasts of a new biotechnology-led "Green Revolution," with healthier food and a more plentiful supply for the world's poor, have so far not materialized. Instead, ag-biotech companies have been put on the defensive, fighting charges that the foods may harm human health and the environment.
Those who support genetically engineered food say protestors are unscientific or harbor a political agenda. Wacky protestor antics reinforce that message. The "Reclaim the Commons" convention protest against the 2004 Biotechnology Industry Organization convention in San Francisco featured puppet-wielding street theater activists, a "Radical Family Collective Kid Zone" and other offbeat activities.
However, GE food skeptic Dave R. Schubert can't be dismissed as some granola-brained ecohippie. He is head of the Salk Institute's Cellular and Neurobiology Lab, with a doctorate in cell biology from UC San Diego.
"The problem is that experimental biotechnology is applied to food with no mandatory safety testing," Schubert said. Allergies have gone up considerably in the decade since genetically engineered foods were introduced, he said.
Schubert carefully adds that he is not saying such a link exists; there just isn't enough evidence to say either way. That's what bothers him.
The peer review test
Schubert has done more than criticize. He has co-written a scientific paper that contends genetically engineered crops are not sufficiently monitored by the U.S. Food and Drug Administration to ensure safety. William Freese, a research analyst with Friends of the Earth, was the paper's lead author.
"Contrary to popular belief, the FDA has not formally approved a single GE crop as safe for human consumption," the paper stated. "Instead, at the end of the consultation, the FDA merely issues a short note summarizing the review process and a letter that conveys the crop developer's assurances that the GE crop is substantially equivalent to its conventional counterpart."
The paper, "Safety Testing and Regulation of Genetically Engineered Foods," was published in the Nov. 16 issue of Biotechnology and Genetic Engineering Review. This scientific journal enlists trained scientists to examine papers for accuracy, a process known as peer review.
Peer-reviewed research is the gold standard of mainstream science. When scientists' work is skeptically reviewed, errors are more easily spotted and corrected.
It's far too early to say whether the paper will mark a shift in the biotechnology community's opinion about GE foods. But the duo have already overcome a major hurdle by placing their paper in a mainstream scientific journal read by those who perform genetic engineering.
Legitimate, but ...
Maarten J. Chrispeels, a prominent pro-GE foods plant biologist who read the Freese-Schubert paper, said the work is scientifically accurate, although it needs to be looked at in the broader context of agricultural development.
Chrispeels is director of the San Diego Center for Molecular Agriculture (www.sdcma.org), an association of local scientists working in agricultural biotechnology. He is also a professor of biology at UC San Diego and a member of the National Academy of Sciences.
"It's a legitimate article, well researched," Chrispeels said.
But despite Chrispeels' kind words, he said there is no reason to doubt the safety of genetically modified foods.
"The article correctly points out that the government relies heavily on company input as we do for drugs," Chrispeels said. "There are no public funds to do such testing, and scientists generally see no need for it. Indeed, the genetic and compositional changes that can be expected from GM plants are no different than those expected from plants improved in 'traditional' ways."
Schubert disagrees. Genetically engineered foods are created by transferring genes between species, using methods that do not exist in nature. Therefore, their effect on man and nature is uncertain, he said.
Scientists use two methods to move genes. Often, the genes are transferred through tamed viruses or microbes that infect the plant of interest. Alternatively, genes are stuck onto microscopic gold or tungsten particles, shot into the cell nucleus with what is colloquially called a "gene gun."
These techniques are also used in production of biotech drugs. The difference, Schubert said, is that the FDA requires tremendous amounts of information about drugs and performs quality checks such as inspecting manufacturing facilities. Without rigorous long-term testing of genetically engineered crops, Schubert said, unforeseen effects on human health could go undetected.
"Allergy is one issue," Schubert said. "Plants make a lot of very nasty chemicals. ... This technology could product novel toxins, but it may not be picked up for a long period of time. That's why these things should be tested before their release. ... Some of the procedures can be done in high school science labs."
Another danger, Schubert said, comes from the open planting of genetically altered crops. This makes it possible for the plants to escape and spread their genes into the wild. Genes that promote hardiness might create environmentally disruptive "superweeds." Genes could also escape from genetically engineered crops that produce pharmaceuticals, which Sacramento-based Ventria Biosciences plans to grow.
"We should have zero tolerance for pharmaceuticals in the food supply, but once they start growing, they're going to get out," Schubert said. "There are alternatives to putting pharmaceuticals in plants: Do it in a type of plant that's not a food plant."
Backlash and stagnation?
After a storm of protest over Ventria's plans to grow pharmaceutical-making rice in California, the company announced that it is moving to Missouri. And last year, San Diego-based Epicyte Pharmaceuticals, which planned to grow pharmaceuticals in corn, was purchased by North Carolina-based Biolex Inc., and the San Diego facilities closed. However, the companies did not say the opposition caused their departure from California.
A report issued Feb. 2 by the Center for Science in the Public Interest, a consumer watchdog group, said that ag-biotech is "stagnating." The report said that the number of biotech crops completing the FDA's voluntary review process has declined from a total of 47 from 1995 through 1999 to 15 in the years 2000-2004.
The report," Withering on the Vine," praised the potential of biotech crops. It stated that the "first generation" of genetically modified crops approved in the 1990s have been found to be safe and beneficial to humans and the environment. But the last few years haven't been as productive.
To fulfill that potential, the report recommended speeding up reviews of genetically engineered crops that are similar to other crops already on the market, such as those with previously used genes. It also urged the biotech industry to develop crops with "broad societal benefits," especially to developing nations.
The report is available on the Center's Web site at: (tinyurl.com/6j4xo).
Benefits from GM foods
Chrispeels puts genetic engineering in a continuum of thousands of years of mankind meddling with nature to make better foods. Today's conventional domesticated crops are far different that their natural ancestors, Chrispeels points out.
Although genetic engineering is a new science, Chrispeels said there is now extensive experience with genetically modified crops, and the hypothetical new threats from these crops have not materialized. That's not to say these crops are free of risk, he emphasized. In every field of human activity, risk must be weighed against benefit.
"You can certify that a food is dangerous, but you cannot certify that a food is absolutely safe, because science cannot prove a negative," Chrispeels said. "The question then becomes: Is there sufficient testing? In my view, there is more than enough, and probably too much, making the whole process too expensive."
Chrispeels said genetically engineered foods could cause allergies, but that is also true of some conventional foods that cause allergies.
Benefits from genetically modified foods have so far been modest, Chrispeels said. However, even apparently trivial benefits can become extremely significant when compounded over the years. During the last 50 years, he said, yields of major staples as measured by pounds per acre have tripled, although the annual increase in yield is just 1 percent.
"If we didn't have this increase over the long run, to get a tripling of the yield, we'd be plowing up the whole country," Chrispeels said.
Additionally, Chrispeels said major benefits to consumers such as reducing heart disease are in the works. This new crop of beneficial genetically engineered foods, Chrispeels said, will include canola oil containing omega-3 fatty acids, which research has shown to reduce the incidence of heart disease.
Arthur Caplan, a prominent bioethicist, agrees with Schubert and Freese that genetically modified crops were released onto the market with too little safety testing. Since it's well known that new technologies and the introduction of new species of animals and plants can produce unforeseen harm, Caplan said, scientists should err on the side of caution.
Caplan, director of Penn Center for Bioethics at the University of Pennsylvania, looked at the ethical issues regarding genetically engineered crops a few years ago with support from Consumers Union and DuPont, which has a division doing agricultural biotechnology. His conclusion is that the public was not given enough information.
The self-testing and disclosure of food companies is "a real weakness in the regulatory system," Caplan said. "It became a giant field test in us."
But at this point, it's probably impractical to roll back the clock and impose rigorous testing of genetically engineered foods, Caplan said, because these foods are already widely consumed.
"If they were going to kill us, we'd all be dead by now," Caplan said. "I'd say at this point that every person in the United States, unless they've got their own food supply, has eaten a fair amount of (GE) foods already."
However, Schubert said that subtler effects would not be so easily detected. If only certain people were allergic to genetically modified foods, their nearly universal prevalence would make it difficult to isolate the cause.
"My bottom line is that the consumer is being hoodwinked by the producers of genetically engineered foods and the federal government into believing that just because the foods are approved by the FDA as safe that they are rigorously tested like drugs," Schubert said. "The fact is that there is no required testing."
Peer review isn't perfect
Scientists are humans, too. They have blind spots and biases. Peer review, the scrutiny of research by skeptical fellow scientists, is modern science's way to weed out the biases.
However, peer review does not guarantee accuracy or acceptance. Questionable articles sometimes slip in. A famous example is a controversial paper by Arpad Pusztai and Stanley Ewen, published in the Lancet, a prestigious British medical journal. The 1999 paper reported that rats fed genetically engineered raw potatoes suffered intestinal damage.
Publication came only after a ferocious struggle featuring claims by the authors that corporate interests tried to suppress their work. Moreover, it was questioned by senior peer reviewers for lack of controls and a too-small sample size. The paper was vigorously attacked by other scientists in an article the Lancet published along with the Pusztai-Ewen paper.
The Lancet's editor, Richard Horton, said he granted publication in part to refute charges of suppression.
A summary of the controversy is on the Web site of Biosafety Information Network and Advisory Service, or BINAS, a service of the U.N. Industrial Development Organization, at tinyurl.com/4cx9c.
Pusztai spells out his own views at tinyurl.com/526ny.