Allergic reactions and other possible health risks
By now, millions of acres of genetically engineered crops have been planted, and nearly two-thirds of the products on our supermarket shelves contain GE ingredients. But GE foods remain poorly studied; scientists simply can't say with any authority that they are absolutely safe for human consumption. In fact, many questions persist.
Essentially, we've been subjected to a massive experiment on human health. What will the results of this experiment be? Stay tuned.
1. Very few studies have been conducted to determine whether genetically engineered foods are harmful to human health.
Genetic engineering is a young, and in many ways poorly understood, technology. Many scientists believe that genetically engineered foods have been rushed much too quickly to market--to boost multinationals' profit margins--before adequate testing has been completed to ensure public health.
Early in 2001, the Royal Society of Canada-the nation's foremost scientific body-said there was insufficient research into the potential allergic effects and toxicity of genetically engineered foods. GM foods could cause "serious risks to human health," the society said.
According to the Washington Post, the "dearth of studies is the legacy of a U.S. policy that considers gene-altered plants and food to be fundamentally the same as conventional ones, a policy some Americans are starting to question....
"And it is the legacy of broken promises by the Food and Drug Administration and the Environmental Protection Agency, both of which have said for the past five years that they intend to write rules to minimize the chances that gene-altered food will cause allergies or damage the environment."
2. Genetic engineering may trigger allergies in people.
Genetic engineering may involve the transfer of new and unidentified proteins from one food into another, with the potential of setting off allergic reactions. And allergies aren't simply a matter of slight discomfort; they can potentially result in life-threatening anaphylactic shock.
Without labeling, people with allergies won't know if they are eating foods that contain genes from other foods to which they are allergic.
In 1996, scientists were stunned to discover that soybeans engineered to include protein-rich genes from the Brazil nut also contained the allergenic properties of the Brazil nut. Animal studies had not revealed the allergenic nature of the mutated soybean. The manufacturer halted the release of the soybean just in time.
But with dozens of new genetically engineered crops under consideration, scientists believe much more extensive testing is required to ensure that those who suffer from allergies won't be affected by these foods.
Scientists also have discovered that Bacillus thuringiensis (Bt), a bacterium that has been spliced into millions of acres of corn, potatoes and cotton, may produce allergies in people.
Science News reported in July 1999 that a study of Ohio crop pickers and handlers shows that Bt "can provoke immunological changes indicative of a developing allergy. With long-term exposure, affected individuals may develop asthma or other serious allergic reactions."
3. Genetic engineering may create new toxins harmful to human health.
Scientists say genetic engineering may produce new toxins, with potentially devastating results for humans. In at least one case, disaster has already happened.
In 1989, a genetically engineered version of tryptophan, a dietary supplement, produced toxic contaminants. Before it was recalled by the Food and Drug Administration, the mutated tryptophan wreaked havoc. Thirty-seven Americans died, 1,500 were permanently disabled, and 5,000 became ill with a blood disorder, eosinophila myalgia syndrome.
4. Genetic engineering may lead to antibiotic resistance.
Genetic engineers use antibiotic "markers" in almost every genetically modified organism to indicate that the organism has been successfully engineered. Scientists believe these antibiotic markers may contribute to the decreasing effectiveness of antibiotics against diseases.
5. Genetic engineering may be linked with a resurgence of infectious diseases.
The journal Microbial Ecology in Health and Disease reported in 1998 that commercial gene technology may be behind a recent resurgence of drug- and antibiotic-resistant infectious diseases. We'll let Dr. Mae-Wan Ho, author of the report (and author of Genetic Engineering: Dream or Nightmare?), take over from here. She says:
"At the heart of the issue is horizontal gene transfer - the transfer of genes by vectors such as viruses and other infectious agents - which is exploited by genetic engineers to make transgenic organisms. While natural vectors respect species barriers, the barrage of artificial vectors made by genetic engineers are designed to cross species barriers, thus greatly enhancing the potential for creating new viral and bacterial pathogens, and spreading drug and antibiotic resistance. Totally unrelated pathogens are showing up with identical virulence and antibiotic resistance genes.
"Recent statistics are frightening. Infectious diseases were responsible for one-third of the 52 million deaths from all causes in 1995. Multi-drug resistant tuberculosis is now estimated to affect 10 million each year with 3 million deaths. At least 50 new viruses attacking humans emerged between 1988 and 1996. Between 1986 and 1996, E. coli 0157:H7 infections increased by 10-fold in England and Wales and 100-fold in Scotland. Vancomycin resistance rose from 3 percent to 95 percent in San Francisco hospitals in the four years between 1993 and 1997. And Staphyloccocus (toxic shock syndrome) is now invulnerable to all known antibiotics.
"The first genetic engineers called for a moratorium in the Asilomar Declaration of 1975, precisely because they were afraid of inadvertently creating new viral and bacterial pathogens. The worst case scenario they envisaged may be taking shape. Commercial pressures led to regulatory guidelines based largely on untested assumptions, all of which have been invalidated by recent scientific findings. For example, biologically "crippled" laboratory strains of bacteria can often survive in the environment to exchange genes with other organisms. Genetic material (DNA) released from dead and living cells, far from being rapidly broken down, actually persists in the environment and transfers to other organisms. Naked viral DNA may be more infectious, and have a wider host range than the virus. Viral DNA resists digestion in the gut of mice, enters the blood stream to infect white blood cells, spleen and liver cells, and may even integrate into the mouse cell genome.
"'We may only be seeing the tip of the iceberg,' the scientists state. 'There is an urgent need to tighten existing regulations.' Instead, the EU is relaxing the guidelines on both deliberate release and contained use of GMOs. 'That is an irresponsible move in the light of existing scientific knowledge.'"
Threats to the environment
When biotech corporations boast that genetic engineering can do wonders for the environment, we would do well to consider the source. After all, some of these companies are the same ones that have invented such deadly pesticides such as DDT and Agent Orange. These pesticides, it was promised, would help the environment; instead, they turned into environmental disasters.
Environmentalists have many concerns about GE foods. Here are a few:
1. The plight of the Monarch butterfly
Cornell University researchers have found that GE corn may be deadly to the Monarch butterfly. In laboratory tests in the spring of 1999, the scientists found that nearly half of Monarch caterpillars that ate milkweed leaves dusted with GE corn pollen died within four days. The surviving Monarchs that ate the genetically mutated corn pollen were much smaller and had smaller appetites than the control Monarchs, which ate normal corn pollen or no pollen at all.
In 2000, Iowa State University scientists found that plants growing in and near cornfields are being dusted with enough GE pollen to kill monarch caterpillars that feed on them.
Already, GE corn is being grown on 20 million acres of American farmland, right in the heart of Monarch's migratory route between Mexico and Canada.
And scientists worry that there may be additional surprising scientific discoveries down the road.
2. Increased pesticide pollution
Many of the new GE crops, such as Roundup Ready soybeans, are designed to allow farmers to spray heavier doses of pesticides on their land. These pesticides inevitably will find their way into our water and food supply, endangering humans and wildlife.
New Scientist magazine reports that many farmers that have converted to GE production use as many pesticides as their conventional counterparts, while some GE farmers now use more pesticides.
And one of Britain's leading safety experts, Malcolm Kane (former head of food safety at the supermarket chain Sainsbury's), has revealed that the limits on pesticide residues in soy had been increased 200-fold to help the GE industry. He warned that higher pesticide residues could appear in a wide variety of foods, ranging from breakfast cereals to biscuits. |
