A prime example is currently under consideration in the Philippines. Scientists have produced a GMO called “Golden Rice” which contains a significant amount of beta-carotene, a compound that the human body converts into Vitamin A. 1.7 million Philippine children suffer from Vitamin A deficiency, which can cause blindness and weaken the immune system, and this deficiency represents a serious systemic issue. (Bloem et. al. 1989) The idea was to introduce Golden Rice into the food supply and therefore curb a public health catastrophe.(Ashton 2013)
Despite these examples of the benefits of GMOs, there have been many arguments against them. Most of these arguments can be easily overcome, or are not fully studied (although this does not reduce their validity), yet the threat to the environment from genetically modified crops is clear and concrete. This paper will outline the threats posed by cross-pollination, increased usage of pesticides, and the overall disruption of the ecosystem.
The first threat posed to the environment by genetically modified crops is less visible than the remainder, and may take several generations to fully play out and show its effect. Cross-pollination is a common and accepted fact of farming. Unlike with animals, genetic material can float for hundreds of miles in the wind, and is designed to withstand natural conditions such as cold, moisture, or even crushing. With genetically modified crops, this means that their seeds could travel well outside the region in which they are intended to be planted, interact with the local flora, and possible cause serious damage to the ecosystem.
This threat will dwarf the danger of non-native species, as genetically modified crops are engineered specifically to increase their fitness in a region. With some of these traits passed on to their progeny, should an effective hybridization of a GMO crop and a natural native plant occur, their offspring could easily impact the entire local ecosystem, forcing out native plants, restricting the food supply of local animals and potentially weakening the watershed.
This threat will only increase as companies attempt to further modify food crops. One particular problem that comes to mind is the temperature tolerance of the organism. By making a plant able to withstand greater heat or cold, the engineers can extend the growing season, increasing profits dramatically. This sounds like an excellent idea, but that is a characteristic that could massively increase fitness in hybrid plants created by cross-pollination.
Another characteristic incorporated into most GMO crops is increased resistance to herbicides and various other compounds used to eliminate pests. In addition to the threat that this genetic modification could pose should it be incorporated into local plant life (as described in the previous section), this resistance encourages heavy and excessive herbicide usage in addition to other poisons in farming and cultivation.
These toxins are generally considered harmful, but necessary. In order to prevent their entire crop from being eaten by bugs and other pests, farmers regularly use such substances. They are not completely effective, as too much usage (the amount needed to completely prevent pests) would damage the plants. With the increased tolerance for these poisons, farmers will have little incentive to not spray massive amounts of highly toxic herbicides to protect their crops. In addition to the effect on the eventual consumer of the food product and the local insect population, these poisons impact the entire local environment.
Herbicides and other atomized toxins are sprayed liberally around most farms. Due to the large number of plants that must be treated, it is not economical to apply the poison directly to each plant, and instead it is simply sprayed, often from airplanes. This means that much of the substance never actually makes it to the plants, and instead simply is wasted on the ground. They are then washed away and soaked into the soil where they eventually end up in the groundwater. From there, they affect the aquatic wildlife, the drinking water for settled areas, and the animal life that depend on that source of water for sustenance. While this occurs regardless of the origins of the crops, the increased resistance to pesticides that is generally incorporated into any genetically engineered food crop makes the amount of pesticide used drastically higher, raising the threat of contamination, and the power of the threat.
Finally, these crops themselves may not effectively integrate into the local environment. The second and third order effects of modified crops and their cultivation have the potential to affect the environment. For example, the monarch butterfly has seen its population shrink significantly due to the lack of milkweed grass on which to lay eggs. This milkweed is not generally considered harmful to crops, but the generalized spraying of pesticides eliminated the population, therefore depriving the butterflies of their ordinary location in which to lay their eggs. This is just one of many examples, the full number of which will probably never be understood. The ecosystem of any particular area is incredibly fragile and any disruption can reverberate among the populations of flora and fauna in devastating ways.
In summation, GMOs have a definitively negative effect on the environment. That does not mean that their use should be completely eliminated, but rather that these deleterious effects should be understood, studied and accounted for. Both farmers and genetic engineers must consider the full ramifications of their actions and take measures to protect the environment that they rely upon and live within.
In order to accomplish these goals, more oversight is needed for the types of modifications made, and the cultivation of these crops. It may be possible to take measures to prevent cross-pollination through netting or similar mechanical methods. Additionally, companies producing GMO crop seeds should consider the ethical ramifications of their work. These companies have a responsibility to ensure that their products do not cause unnecessary harm to the regions in which they are planted, and it is insufficient to simply blame farmers for the damage done.
As illustrated in the opening anecdote on Golden Rice, GMOs have the potential to seriously help world food crises and developing nations. Yet, like all other scientific advances, they must be monitored and care must be taken to prevent abuse.