Since the time that humans first started cultivating plants and raising animals for food, we have been striving to make food healthier and food production more efficient. Using the natural mechanisms of cross-breeding, which is nature's way of ensuring genetic diversity, we have been able to affect the biological traits of offspring by selecting and mating the parents that carry the traits we desire. Cross-breeding can only take place between species of plants and animals that are closely related genetically.
With the advent of genetic engineering, scientists are now able to surpass the natural barriers of cross-breeding. Genetic engineers can cut out bits of a living organisms DNA, called genes, and splice them into totally unrelated species. These scientists use enzymes to break the DNA strand at certain places, insert new segments, and "stitch" the strand back together again. They can "cut and paste" genes from one organism into another so that the genetic make-up of the organism is changed and its natural traits are manipulated in particular directions. Genetic engineering changes nature rather than using its own power.
DNA: The Blueprint For Life
A gene is a segment of DNA. Genes carry messages encoded in their chemical structure, so that together the genetic make-up of a living cell determines physical traits of that organism. The genes carry all the chemical instructions needed to make the organism behave in a certain way, and since they are passed on from one generation to the next, offspring inherit these traits from their parents.
There are literally millions of genes in a living organism and they don't just work on a "one gene, one trait" system. Genes are complex and work together to perform certain biological functions. By altering the genetic code of living organisms, genetic engineers are manipulating life processes. As more and more genes are isolated from their natural sources, scientists are able to control more and more aspects of life.
What Is Being Genetically Engineered?
The majority of the world's most important food crops have already been either tested for genetically engineered versions, or are under development. So far at least 38 different crop species have been genetically engineered and tested in field trials. Animal genes are going into plants, bacteria genes into food crops, and even human genes are being used to change animals and plants. Thousands of other new foodstuffs are waiting in the wings. Already in the laboratory a human gene has been added to salmon, trout, and rice; a chicken gene to potatoes; a fish gene to strawberries, mouse genes into tobacco; and bacteria and virus genes into cucumbers and tomatoes.
What Are The Impacts of Genetic Engineering?
"This is an imperfect technology with inherent dangers. ... It is the unpredictability of the outcomes that is most worrying." Dr. Michael Antoniou - Senior Lecturer in Molecular Biology - London
Genetic engineering creates whole new life forms. These organisms are alive --they can mutate, multiply, breed with other living things and go on breeding for generations to come. All over the world we have seen examples of long-term damage when non-indigenous species have been introduced into new environments. We know that changing one element of the environment sets off a domino effect of cascading changes throughout entire ecosystems. Yet industry maintains that its foreign species will not cause problems.
Who Says It's Safe To Eat?
Regulatory authorities who have allowed the use and distribution of genetically engineered products, including the USDA, FDA, EPA and the European Commission, rely solely on safety testing provided by the GE companies themselves.
Multinational companies who market the new crops say they are safe, but they have done scant tests to prove it. Industry health studies on GE crops are very limited in scope and duration. These studies did not include assessing the health affects of increased exposure to herbicide due to residues on herbicide-resistant foodsources, or the affects of increased insecticide exposure due to pesticides incorporated in foodstuff. The only time the FDA requires further testing of a GE foodstuff is if one of 8 to 10 known allergens has been engineered into a plant. Assessing health hazards beyond a few well known allergens is not required.
Allergies could very well increase. Many people are allergic to food plants because of proteins produced by the plant as a defense against diseases and pests. Since genetically engineered plants are specifically designed to produce increased quantities of these proteins, the risk of allergies is also increased.
Governments have expressed fears that crops containing an ampicillin resistance gene could undermine the treatment of human and animal disease. Ampicillin is one of our most important antibiotics. It is feared that the resistance gene could spread to harmful bacteria - making them immune to this vital treatment.
Who Says Its Safe To Grow?
Field trials to measure environmental impacts of GE crops are also usually short term and small scale, rarely lasting for more than one growing season. It could take years for most ecological effects, such as genetic pollution and increasing pest resistance to pesticides, to be seen. Tiny trial plots cannot possibly reflect the damage that could be done by planting huge tracts of countryside with genetically engineered seeds.
Scientists at Riso National Laboratory in Denmark have found that, through spontaneous cross-fertilization, genetically engineered canola can pass its herbicide resistance genes to weedy relatives. The offspring resulting from the cross-breeding of the GE and weedy plants were not only herbicide-resistant, they also were capable of passing on resistance to subsequent generations.
It is generally regarded as bad pest management practice to use the same pesticide, or one with the same mode of action, continually on a cropped area. This course of action inevitably leads to a buildup of resistance to the toxin in crop pests. Farmers using crop chemicals have seen over the years that, as pest resistance develops, more chemicals are needed to have the same effect. Resistance to Monsantos Roundup herbicide has been documented to occur after relatively minimal exposure over a long period--one Australian farmer noted resistance to Roundup after fewer than six applications over the course of ten years. Tiny test plots cant possibly determine the long range impacts of genetically engineered crops.
The Precautionary Principle
Precautionary standards are a normal part of everyday life -- when the prospect of harm is large and the uncertainty is great, our ability to predict the future is limited so we take a precautionary approach. The Precautionary Principle holds that, 1) the burden of proof of safety rests with the proponent of a new technology, not the public; and 2) where there are threats of serious or irreversible damage, lack of science should not be used as an excuse for postponing measures to prevent environmental degradation.
GREENPEACE, April 1997
1436 U St. NW, Washington DC 20009
This report © Greenpeace 1997