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List of Environmental Risks of GM Foods

Genetically modified foods or GMOs (genetically modified organisms) are crop plants that have been modified by molecular biologists, and which are usually intended for human or animal consumption. Plants may be modified for a variety of reasons. They may be altered to enhance the size or quantity of fruit they produce, or to increase their resistance to herbicides. GM crops are widely grown throughout the world, but they do pose some environmental risks.

  1. Allergy Risks in Humans

    • In some cases, genetically modified foods contain DNA from two distinct plants or food products. If a person who is allergic to nuts eats a genetically modified bean that was spliced with nut DNA, they could have an allergic reaction without being aware of the cause. According to the European Federation of Biotechnology, this almost occurred in 1996, when Brazil nut genes were spliced into soybeans to provide added protein. Brazil nut allergies can cause some people to go into anaphylactic shock, which can be fatal. Fortunately, human and animal trials of the product revealed this problem, and the new soybean was never put on the market. However, it is conceivable that less severe allergens could be transmitted into genetically modified foods undetected.

    Harm to Insect Populations

    • Some genetically engineered crops contain genes from the bacteria Bacillus thuringiensis, or "Bt," which is a naturally occurring insecticide. Unfortunately, this insecticide can be harmful to a wide variety of insects that are not considered pests. In one study published in Nature, pollen from Bt corn was shown to cause increased mortality rates in Monarch butterfly caterpillars, as well as in other insects. Even if the insects do not have contact with the modified crop itself, pollen from plants containing Bt can spread to other plants and be transmitted quickly among insect populations. Some scientists are concerned that insects will gradually develop immunities to Bt, which will require farmers to use more and more pesticides to protect their crops.

    Unwanted Gene Transfer

    • Many GM crops are engineered for herbicide tolerance, so that farmers can spray large amounts of weed-killing chemicals on their fields without harming their crops. This can be problematic in itself, since it has led to an increased use of herbicides among farmers, according to a report by the Institute of Science in Society. These herbicides eventually find their way into rivers, lakes and water supplies, and can be harmful to humans, animals and ecosystems. There is also a concern that these crops will crossbreed with weeds, creating new herbicide-resistant weed varieties. Crossbreeding among plants does not always occur as a result of genetic modification. It also occurs naturally, resulting in new species and new adaptations to changing environments. If weeds were to acquire the herbicide tolerance of genetically modified crops, they would become extremely difficult to kill and pose new risks to the health of the crops and farm productivity. This would create a need for newer, stronger herbicides, which could in turn pose an increased risk to the environment.

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