Subcommittee E: Section 1

Direct Damage

by Rebecca Reilly

Various studies performed within the past several years indicate that transgenic crops are a possible cause of direct, non-genetic, damage to the environment. However, all observed effects thus far have been equivalent those caused by herbicide and pesticide treatments on traditional crops.

Some bioengineered products, like Monsanto’s "Roundup Ready" soybean, involve the application of an herbicide, in this case Roundup, to the fields. While the weeds are killed, the transgenic crops remain unharmed by the application. However, other beings are harmed by this product. In fact, Roundup is "the third most commonly reported source of pesticide-related illness among California farmworkers". Another area for potential concern is that, depending on the application method and weather conditions at the time, Roundup can drift up to 800 yards from the area to which it was applied. This could necessitate that farmers within that area use the "Roundup Ready" crops in their fields in order to avoid damage from the weed killer, thus decreasing the amount of natural crops produced, and perpetuating any problems associated with bioengineered food crops. It is important to note here that such particle drift can occur with any herbicide, is not specific to this product, and, in fact, is less likely to occur with Roundup than with many other herbicides because Roundup is "virtually non-volatile". These transgenic crops involving herbicides seem to entail potential damage to surrounding plants and animals, but no more so than other, more traditional, herbicides.

Various laboratory studies have found that damage done to predators could be very significant. The Swiss Federal Research Station for Agroecology and Agriculture found that the insects called green lacewings "have elevated mortality" when they consume other insects that consume Bacillus thuringiensis,or Bt corn. Bt is a common type of toxin used in genetically engineered crops, and is a natural pesticide from bacteria. Recently, a study at Cornell University found that the pollen from Bt corn can kill the caterpillars of Danaus plexippus, the monarch butterfly. Almost half of the monarch butterfly larvae that were fed on leaves that had the pollen of Bt corn died after four days, while those not exposed to the pollen did not die. The larvae that survived the Bt corn pollen "ate less, grew more slowly and suffered higher mortality" than larvae that were not exposed to this type of pollen. Causing death to insects seems to be a characteristic of several Bt products. This is also an area for concern because the pollen of Bt corn, for example, can be carried by the wind for up to 60 yards.4 This pollen could pose a threat to insects in the area to which the pollen drifts, thus extending the area in which Bt has an effect on the ecosystem. However, it is vital to note that Bt, in addition to its use in genetically engineered crops, is also used as a pesticide in traditional and organic farming. Again, transgenic crops do not seem, at this point in time, to pose more of a threat to the environment than do other crops and the methods used to encourage their cultivation.

One potential cause for concern relating to bioengineered crops involves the pest populations that are targeted by specific crops. While the pests may die, which is the desired effect, their disappearance could allow other species that are naturally resistant to the pesticide to thrive and become overabundant.

Transgenic crops can pose a danger to people, predators, and other plants. However, their toxicity has not been proven to be more severe than that associated with the treatments used in traditional farming. Direct damage to the environment can be associated with the use of transgenic crops, but the same can be said, and to the same extent, of pesticides and herbicides used by other farmers.

Pennybacker, Mindy. "Fooling Mother Nature." Sierra 83 (1998): 14-15.

"Application Management." at http://http://www.roundupready.com/soybeans/ Accessed 12/11/99.

Stix, Gary. "The Butterfly Effect." Scientific American 281 (1999): 28-29.

Tangley, Laura. "Attack of the Killer Corn." U.S. News & World Report 126 (1999): 69.

Losey, John E., Linda S. Rayor, and Maureen E. Carter. "Transgenic Pollen Harms Monarch Larvae." Nature 399 (1999): 214.

Snow, Allison A., and Pedro Moran Palma. "Commercialization of Transgenic Plants: Potential Ecological Risks." BioScience 47 (1997): 86-96.

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