Another risk is the possible loss of beneficial insects. For example, Bt maize, maize genetically modified to produce the Bt protein which kills the corn borer insect if it attempts to eat the maize, contains the Bt toxin4. Some claim this will travel through the food chain and kill beneficial insects, including lacewings and ladybirds. Another concern is that if GM crops are more effective at killing target insects this might deprive other organisms which prey on them. For example, in America it is feared the number of skylarks may fall due to a reduction in Chenopodium album weeds which they feed on. The fall in weeds has been the effect of planting weedkiller-resistant sugar beet5.
Resistance against pesticides from unwanted weeds and insects is also a problem. It is known the more frequently a pesticide is used the more likely resistance to it will emerge in the weeds and insects which it is designed to kill4. The concern with GM crops is that increased use of a single ‘broad spectrum’ herbicide on
successive crops, in preference to a mix of ‘narrow spectrum’ herbicides will lead to more weeds becoming resistant to that herbicide. Furthermore, viruses tend to recombine to create new viruses and new diseases for farmers to fight4. As new viruses develop all the time it is inevitable that some will emerge from GM applications. Critics of GM technology are fearful that new, highly damaging viruses could develop which may be uncontrollable.
Despite these possible dangers to the environment, GM crops are being produced commercially for human consumption in the US, Argentina, China, and forty other nations due to the economic benefits farmers are experiencing4. These include less utilisation of pesticides6. Much of the current GM technology is aimed at producing pesticide tolerant crops so that only one or two applications of pesticides are needed to control weeds/insects, rather than numerous. For example, GM soya has been modified to make it tolerant to the herbicide glyphosate – a ‘broad spectrum’ weedkiller which cannot be used on non-GM soya as it would kill both the weeds and the soya4. With conventional soya, several ‘narrow spectrum’ herbicides have to be used to kill specific weeds. With herbicide tolerant GM soya, however, glyphosate can be used to control most weeds without killing the soya. Thus, farmers cost of production are minimised as they pay for fewer chemicals, which in turn brings savings in the energy which would have been needed to produce and transport those chemicals.
Following on from this, making crops resistant to insects and diseases and reducing weeds should lead to fewer crop losses, thereby increasing yields. Worldwide 7% of the annual maize harvest is destroyed by the European corn borer. If Bt maize delivers its promise maize yields in Europe and the US could increase by 7-10 million tonnes. Furthermore, it has been estimated yields of GM soya and GM potatoes could both rise by approximately 5%4.
Another benefit is the reduced soil erosion. For example, with non-GM soya, weeds are cleared prior to seeds being planted. With herbicide tolerant soya, this is not necessary as the weeds can be more easily controlled at a later stage. GM seeds are planted by placing them directly into relatively undisturbed soil. This conserves moisture and soil fauna and flora, also reducing water and wind erosion4.
Perhaps one of the greatest potential assets of GM crops, however, is the possibility of increasing food supply in Third World nations. The crop yields of developing countries are significantly lower due to problems with insects, weeds, and diseases. Globally there are 100 million people starving and 800 million hungry7. GM crops could be used to reduce this number by, for example, enabling crops to grow in less fertile areas. Drought resistance could be built into plants allowing them to develop in arid conditions, whilst plants made resistant to frost could grow in colder climates. Pesticide tolerant crops could also be used to increase yields.
Nevertheless, is it morally permissible to proceed with a harmful cause of action if we are unsure of the consequences? Genetic engineering is still in its relative infancy, and from the risks it is evident insufficient research has been carried out. The situation feels eerily like deja-vu, bringing back memories of the disastrous consequences chemicals such as DDT and thalidomide brought. For both, inadequate analysis was carried out to investigate the possible long-term affects the substances may have on people and the environment. Genetic engineering, however, has undoubtedly a far worse risk potential than any pharmaceutical drug or biotechnological advance developed in the past. With genetic engineering you are tampering with the very essence of life because the manipulation of genes is involved.
Nonetheless, the possible benefits GM crops could bring to humankind, particularly of feeding the world, may perhaps justify genetic engineering: you would be manipulating the blueprint of life to save lives. Even so, the potential risks to the environment cannot be disregarded as devastating results may follow. A solution therefore would be to continue research on GM crops investigating their short-term and long-term affects, thereby hopefully finding answers to their potential risks. For example, one solution found to tackle the problem of ‘escaping’ genes through cross-pollination would be to further modify GM crops making the seeds they produce sterile7. This terminator technology is currently at examination stage. With research, fears surrounding GM crops can be verified to being either true or false, leaving people confident of the full consequences they may cause to the environment.
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