When Rachel Carson wrote Silent Spring in 1962, she stunned the world and created great controversy. More than three generations later, her words have become inspiration for harmony with nature - yet we continue to silence nature.
Monarch butterflies are being threatened by genetically altered corn. Often seen flitting silently through gardens, Monarchs are prized for their beauty and for the wonder of their long autumn migration - up to 3000 miles, from Canada to central Mexico's forests. The adults are valuable as pollinators of many flowers, including sunflowers and asters.
Results of field studies conducted at Iowa State University, released in August 2000, showed 20 percent of monarch larvae died after being exposed to pollen from Bt corn that had blown onto plants the monarch caterpillars eat. The butterflies feed exclusively on milkweed plants which commonly grow in or near cornfields.
Scientists can now create amazing organisms by altering genes. For instance, the gene for a protein that keeps the arctic flounder from freezing has been inserted into tomatoes and strawberries to keep the produce from dying during a frost.
Bioengineered crops in the near future will give consumers cooking oils with more healthful types of fatty acids. Farmers may be able to grow crops on lands that were too dry or salty for traditional varieties. Staple foods such as rice can be enhanced with extra nutrients, beta-carotene and iron. Such advances are just around the corner, and could go far to reduce the toll of childhood blindness, malnutrition, and anemia in some areas of the world.
"The potential of this equals the Industrial Revolution," Jim Quick, head of the agricultural sciences department at Colorado State University. "We will be able to feed the world and help the environment."
The outcry against biotechnology is mostly a matter of risks vs. benefits. According to Quick, genetic engineering has been happening for the past hundred years. "The main difference," notes Dr. Ruth Kava, director of nutrition for the Monsanto-backed American Council on Science and Health, "is that the modern processes are much more specific. Instead of transferring hundreds or even thousands of genes with traditional breeding, modern methods allow biologists to move only the gene or genes that are known to have the desired effects."
While genetic engineers argue their creations are no different than crossbreeding that has occurred for thousands of years, critics say not so. Natural boundaries are violated, they claim, something that never occurred in nature such as crossing animals with plants, strawberries and carrots with fish; grains, nuts, seeds and legumes with bacteria, viruses, and fungi; or human genes with swine.
GE proponents say the U.S. Department of Agriculture (USDA) and the U.S. Food and Drug Administration (FDA) adequately test and sign off on new GE products. Opponents disagree, citing the fact that biotech potatoes used to make fast-food french fries are registered with the U.S. Environmental Protection Agency (EPA) as pesticides, not foods, and are thus not under FDA jurisdiction. FDA's own reports show it accepted testing results from biotech firms instead of performing their own tests.
DNA fragments are blasted past a cells membrane with a "gene gun" shooting in foreign genetic materials. According to Richard Lacey Ph.D., a medical microbiologist at the University of Leeds, "Wedging foreign genetic material in an essentially random manner causes some degree of disruption. It is impossible to predict what specific problems could result."
And that is precisely where much of the controversy lies: No one knows where were headed with the technology. "What it boils down to is, its impossible to prove a negative," Colorado State University wheat breeder Scott Haley, Ph.D. said.
According to Ron Epstein, Ph.D. professor at San Francisco State University, the main environmental problem with genetically engineered food plants and animals is that when they escape into the wild, they permanently disrupt ecosystems which are the products of billions of years of evolution. Another potential problem is viruses. By their very nature, viruses invade the genetic material of their hosts and often break apart and recombine using part of the hosts genetic material to crate new viruses. When this happens with genetically engineered plants and animals outside of the laboratory, new viruses will be related that incorporate genetically engineered genetic material. The viruses will then spread and, because they could not have been naturally produced, there may be no natural defenses against them.
Some problems related to genetic engineering have already surfaced. Concerns include:
Bacillus thuringiensis, or Bt, is a natural soil bacterium long used to thwart caterpillars and other pests that thrive on corn, potatoes and other crops. Biotech companies slip Bt into corn so that every cell in every part of the plant always exudes this insect toxin. One study by researchers at New York University found that Bt engineered into crops leached from roots and remained in the soil for at least eight months. Researchers predict insects will develop immunity to Bt within five years.
Toxicity to soil. Biotech scientists say that GE seeds and plants will help the environment by reducing toxic herbicide and pesticide use. The majority of research for future products involves transgenic strains for increased chemical resistance. According to an article by R.J. Goldburg, scientists predict herbicide use will triple as a result of using GE products.
Genetically modified plants may crossbreed with wild species to produce "superweeds," which cannot be eliminated using standard herbicides. Genetically modified Bt endotoxin remains in the soil at least 18 months, according to researchers Marc Lappe and Britt Bailey, and can be transported to wild plants creating superweeds that will disturb the balance of nature.
A 1996 study in Denmark and in Britain showed superweeds growing near GE plants in just one generation. A U.S. study showed the glufosinate-resistant superweed to be just as fertile as non-polluted weeds. Scientists suspect that Monsanto's wheat will hybridize with goat grass, creating an invulnerable superweed. "Everything we do in plant breeding is a risk," Quick said. "Our job is to assess those tests."
Herbicide-resistant"Supertrees" are being developed with leaves exuding toxic chemicals to kill caterpillars and other surrounding insects. Herbicides can be sprayed from the air to literally kill all of surrounding life except the GE trees. The trees are often sterile and flowerless, in contrast to trees that can host thousands of species of insects, fungi, mammals and birds in an interconnected ecosphere. Pollen from the supertrees has traveled as much as 400 miles - roughly one-fifth the distance across the United States.
Crops which have been genetically modified to contain their own insecticide, such as Bt, cause insects to become resistant to the insecticide. Lab tests indicate that common plant pests such as cottonboll worms will evolve into superpests immune from Bt sprays used by farmers. A recent "stink bug" epidemic in North Carolina and Georgia seems linked to GE plants that the bugs love.
Fish and marine life are threatened by accidental release of GE fish currently under development by bioengineering firms in several countries - fast growing trout, carp, salmon and catfish several times the normal size can wipe out their competitors in the wild. There are no regulations for their containment, and some have escaped from their "net pens." One such incident recently occurred in the Philippines, threatening local fish supplies.
Killing beneficial insects.
Crops which have been genetically modified to resist insects kill not just the "target inset", such as the weevil, but beneficial insects such as the Monarch butterfly. Swiss scientists found Bt crops killed green lacewings that feed on pests. A 1997 study in New Scientist indicates honeybees may be harmed by feeding on proteins found in GE canola flowers. Other studies relate to the death of bees during a contained trial with Monsanto's Bt cotton.
Poisonous to mammals
Toxic compounds such as glyphosphate (roundUp) an Bromoxynil are used on genetically modified crops. The Environmental Protection Agency (EPA) has approved the use of Bromaxynil on cotton despite acknowledging "...serious concerns about developmental risks to infants and children." In a study with GE potatoes, spliced with DNA from the snowdrop plant and a viral promoter (CaMV), the resulting plant was poisonous to rats - damaging vital organs, the stomach lining and immune system.
Carrying GE pollen by wind, rain, birds, bees, insects, fungus, bacteria the entire chain of life becomes involved. Once released, there is no cleanup or recall possible. In a recent study in England, wild honey was found to be contaminated, indicating that bees are likely to pollinate organic plants and trees with transgenic elements.
One of the hopes raised by biotechnology is that it will solve the worlds hunger. Some high tech agriculture does offer higher single crop yields. But according to Charles Benbrook, former director of the Board of Agriculture at the National Academy of Sciences, organic farming techniques generally offer higher per acre yields. In a study of 8,200 field trials, Roundup Ready soybeans produced fewer bushels of soy than non-GE.
In other studies Bt corn yieldwas higher. But this did not lead to greater profit because GE related costs in terms of insecticides, fertilizer and labor were nearly $4 more per acre.
Fragility of future agriculture. The nature of genetic modification and long term effects are not well understood. During the Irish potato famine of the 19th century, farmers grew limited varieties of potatoes. This allowed a crop blight to spread throughout Ireland. GE crops throughout the world are currently in trouble potato late blight is presently attacking Russian potato crops, and a citrus canker blight in January seriously threatened Florida's $8.5 billion fruit industry.
Research is moving forward to bring the first genetically modified wheat to market as early as 2003. The top importers of U.S. wheat, including Egypt and Japan, have already said they want nothing to do with GE wheat.
"There is tremendous potential to address many problems of humankind with this technology. To discard it based on emotional issues would be a great disservice," Haley said.
"I feel the real future in food production lies in further development of sustainable agricultural strategies, such as crop rotation, crop diversification, and natural pest control methods. The objectives that scientists hope to achieve through genetic manipulations can be accomplished much more simply, safely, and cost-effectively through these strategies," John Fagan, a molecular biologist specializing in genetic techniques in cancer research, said.