Question

Discuss the various environmental risks associated with genetically modified crops.

Answer 1

1. Out-crossing: Out-crossing refers to the transfer of engineered genes, i.e., transgenes from genetically modified crops to conventional, cultivated plants or to related crop species in the wild. This may happen by means of wind, insect pollination, or other transfer. According to the World Health Organisation (WHO), there is a very real risk of out-crossing in nature. The foreign genes can cross with and contaminate other species, resulting in a hybridisation of the genetically modified crop plant with a non-GMO plant. This could radically alter entire ecosystems if the hybrid plants thrived.
   Out-crossing can also have an indirect effect on food safety and security as the contaminated species make their way into the food chain. In a September 2010 paper, for example, the World Health Organisation reports an incident in which traces of a GM variety of corn that was only approved for use as livestock feed were found in corn products intended for human consumption in the U.S. market.
2. Unintended harm to Non-target Organisms: A 1999 laboratory study published in Nature showed that pollen from a variety of GM corn resulted in high mortality rates among monarch butterfly caterpillars. Even though these caterpillars feed on milkweed plants, not corn, there is a concern that if pollen from the GM com is blown into a neighbouring field with milkweed plants, the caterpillars would consume it and perish. The potential risk posed to non-target organisms remains the subject of acrimonious debate.
   Leakage of GM proteins into soil can also disturb the ecosystem.