Organic farmers debate genetic engineering of crops – Is industry just hurrying up evolution, or is it harming the world's ecology?
Deborah K. Rich, Special to The Chronicle
Saturday, February 11, 2006

Should genetically modified seeds be allowed in organic agriculture?

At the 26th annual Ecological Farming Conference in Pacific Grove in late January, Dave Henson, director of the Occidental Arts and Ecology Center in Occidental and a steering committee member of the Californians for GE-Free Agriculture campaign, and Charles Benbrook, chief scientist at the Organic Center, addressed the question.

Arguing the case for genetically modified crops were Martina Newell-McGloughlin, director of the University of California's Systemwide Biotechnology Research and Education Program, and Autar Mattoo, plant physiologist with the USDA's Agricultural Research Service.

The National Organics Program, which stipulates what materials and systems organic growers may use, prohibits the use of genetically modified crops. Henson and Benbrook say they approve of this position, at least until multi-generational peer-review studies demonstrate otherwise.

Genetic modification (also called genetic engineering) refers to the manipulation of an organism's genes. Inactive genes may be turned on, active genes turned off or genes from distantly related species or species in different kingdoms of life spliced in. Crop plants have been genetically modified to withstand applications of herbicides and to produce proteins toxic to some classes of insects.

The long-term implications of genetically modified crops for human and environmental health and for food system security are too profound to be left to a handful of corporations subject to the pressures of quarterly earnings reports to evaluate, say Henson and Benbrook. The power to shuffle genes within and among species is unprecedented, and the science is too young to make informed decisions about the risks of the technologies.

"There is not a sufficient foundation of science to conclude that food safety and environmental problems will not result from the mixing in of foreign DNA into crop genomes," says Benbrook.

Newell-McGloughlin and Mattoo say that nature already has set the precedent for transferring genes between dissimilar organisms, as evidenced by genetic sequences in plants that are the same as those found in other species. Even our own genetic sequencing, says Mattoo, has partially developed through interaction with other genomes. "The human genome for vision was brought to us from very old photosynthetic bacteria. Nature mixes genes among species; it just takes time. The scientists are trying to do it faster."

Mattoo, who has studied genetically modified tomatoes, says that he has not found any evidence of chemical differences between regular tomatoes and modified tomatoes. "Work should continue with genetically modified crops," Mattoo says, "because we can't comprehend what the future will hold and need to keep an open view." He suggests that genetic modifications that benefit organic growing systems -- like high-producing cover crops that senesce early and decompose quickly -- may soon be possible.

Henson asserts that cross-species exchange occurring during the course of evolution is no argument for making this happen through entirely different means. The unintended environmental consequences and the human health concerns that have emerged in the 10 years since the commercialization of the first genetically modified crops should cause not only organic growers, but agricultural scientists, conventional farmers and consumers to demand rigorous scientific study of the matter. "Organics is one of the last lines of defense for all time," says Henson.

The USDA, EPA and FDA had the mandate and the opportunity to test the safety of patching genetic sequences into crop plants before authorizing the commercialization of the first modified crops in the mid-1990s. But the regulatory agencies decided that genetic engineering was simply the continuation of crop improvement that began when the first Fertile Crescent farmers began saving seed 10,000 years ago. They ruled that these new crops were substantially the same as any other crop variety we had developed and required no special regulation. When Monsanto and other developers of genetically modified crops assured the regulators that the new crops were not acutely toxic, federal agencies asked few other questions.

Benbrook cites the case of the genetically modified field pea developed in Australia that was found, just prior to commercialization, to trigger a "pronounced and sustained immune response" in mice. Australia's Commonwealth Scientific and Industrial Research Organization, which developed the pea, canceled its release late last year. "Not a single one of the genetically engineered crops already on the market have been tested with this type of state-of-the-art assay process," says Benbrook.

Newell-McGloughlin and Mattoo say that rather than the pea demonstrating the failure of regulatory systems, the case showed that the science of evaluating modified crops was improving.

But Henson says the risks are too great to release these crops first and ask questions later. After the debate, Henson elaborated upon the implications of genetically modified crops for environmental and human health and food system security.

Because pollen drifts and is undiscriminating about where it lands, genetically modified crops can transfer their characteristics to weedy relatives. Monsanto has modified canola to tolerate applications of glyphosate herbicides. Roundup, Monsanto's brand of glyphosate herbicide, is the most widely used agricultural herbicide in the world. Canola, meanwhile, is in the Brassicaceae family, which includes not only most of the world's winter vegetables like cabbage, broccoli, turnips and kale but wild radish and mustard as well. "Tolerance to Roundup," says Henson, "is being conveyed through cross-pollination to weedy relatives (of canola), and that leaves the Caltrans of every state and county and country unable to kill the weeds -- as they have to do for fire protection -- along the freeways anymore. What do they have to use now? 2,4-D. A far more persistent toxic pesticide than Roundup."

Drifting pollen also contaminates unmodified varieties of the same species. For example, it is difficult to maintain buffer zones between a field of modified corn and a field of unmodified corn sufficient to eliminate the risk of pollen transfer. Contamination jeopardizes the grower's marketing options because many foreign markets ban genetically modified foods.

Since seed doesn't stay in place any better than pollen does, genetically modified crops jeopardize the genetic diversity of crops. Seed travels in the digestive tracts of birds and animals, on muddy boots and truck tires, on wind and in the cheeks of mice and ground squirrels. It is also carried around the world in the form of food aid. Which is probably how corn in Oaxaca, Mexico, became contaminated despite Mexico's ban on planting genetically modified corn. The thousands of native corn varieties that grow in Oaxaca -- considered the center of diversity of corn -- comprise a genetic library to which the world turns when it needs varieties naturally adapted to niche environments, or with resistance to new pests or diseases, or with a preferred texture and flavor. If every "book" in the library becomes imprinted with the same story, the world will lose the options embedded in the varieties.

Then there is the question of who owns the books. The lawyers are having a field day arguing who is liable and who owns the contaminated crop when modified plants sprout up where they shouldn't. The patents for genetically modified crops are written such that the seed company has a legal claim not only on the seed it sells but also on the plants grown from the seed, wherever those plants crop up. One of the reasons that the developers of genetically modified crops are so eager to force their global use is to avoid the "liability train wreck" that is fast approaching, says Henson.

When interviewed after the debate, Newell-McGloughlin acknowledged that pollen floats but said she believes the risks of crop contamination are manageable and, in many cases, worth taking for the sake of crop improvement, especially in an increasingly hungry world that will require either the farming of more acres to feed or higher yields from existing acres. "It's all a question of checks and balances and of cost-benefit analysis," Newell-McGloughlin says.

The spread of genetically modified crops can also increase the speed with which agricultural pests evolve resistance to controls. The use of Roundup herbicides on the more than 80 million acres planted to Roundup-resistant crops in the United States has created a situation where only weeds that are naturally resistant to glyphosate herbicides survive to reproduce -- the so-called "superweeds." "This has happened in spades already," says Henson. "Mare's tail, a weed in the Southeast and East Coast of the United States, grows 5 to 7 feet tall and has 200,000 seeds per plant, and in just eight years it has become resistant to Roundup."

Beyond the environmental issues, we know little about the long-term impacts of consuming genetically modified food crops on human health, says Henson. We don't know, for example, what plant health or nutritional qualities we are compromising when we force a plant to withstand herbicides or to produce its own insecticides. No matter how many tricks they can perform, plants have only a finite amount of energy to spend during their life cycle.

We also don't know how safe it is to incorporate modified plants into our diet and into that of our animals. Advocates of genetic-engineering argue that we have nothing to fear from consuming these crops because the new genes ultimately express themselves as proteins, lignins and carbohydrates. However, as in the case of the Australian pea, not all proteins are created equal, and worrisome results are emerging from feeding trials that look beyond immediate toxicity. Scientists have observed abnormal white and red blood cell counts, inflammation of the liver and unexplained growths in the stomachs and small intestines of rats fed genetically modified corn and potatoes.

Meanwhile, the claim that no one is dying from eating genetically modified foods is questionable because no one is monitoring long-term human health impacts.

"I don't know that genetically engineered foods are bad for you," says Henson. "Nobody knows. But there is enough evidence that would lead any routinely robust scientific process to say, 'We have some science to do here before we just release these widely into the food stream.' "

Finally, Henson says, we need public debate about the implications of genetically modified crops for food security. The release of genetically modified crops has been accompanied by an unprecedented consolidation of the seed industry. In the 1990s, chemical companies catapulted themselves into the seed business to capitalize on genetic-engineering technologies. By purchasing seed companies, they bought market share, seed production and marketing expertise, plant patents and seed stock. Ten companies, with Monsanto, Dupont and Syngenta firmly in the lead, now control half of the world's commercial seed sales. Monsanto alone sells 41 percent of the world's corn, 25 percent of its soybeans and more than 30 percent of its cucumbers, hot peppers and beans other than soybeans. Monsanto also sells 88 percent of the world's genetically modified seeds.

"Monsanto," says Henson, "is systematically buying privately held seed companies and retiring their seed stock." Varieties that farmers have purchased for years vanish, and the "local" seed company simply becomes a distribution center for Monsanto's seeds.

"We have to ask," says Henson "whether we bank on a corporate-controlled, extremely consolidated vertically integrated food system, or on a robust, diversified horizontal system."

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