In the U.S. alone, farmers spray, spread, and otherwise administer more than 970 million tons of insect- and plant-killers every year. These pose threats to the environment. Pesticide residues linger on crops and in soil, find their way into the guts of wildlife that eat contaminated foliage, and leach into groundwater and wash into streams.

If a crop boasts its own ability to resist invertebrate predators, then farmers can use far fewer chemicals. In 1999, according to the Environmental Protection Agency, cotton farmers in states raising significant amounts of cotton genetically modified to withstand pests sprayed 21 percent less insecticide -- that is, they sprayed one to two times rather than eight to ten.

Similarly, endorsers profess that farmers raising crops bearing herbicide resistance -- such as those using the Monsanto-crafted soybean that is resistant to the company's broad-spectrum weed killer Roundup -- will use fewer chemicals in a season than they would while growing conventional soybeans.

Industry spokespersons acknowledge the possibility that cross-pollination could occur between some types of GM crops and weeds. But they claim there are ways around that, such as creating GM crops that are male-sterile -- that is, produce no pollen -- or modifying a GM plant so its pollen doesn't have the introduced gene. As for the danger of pests growing tolerant of plant-borne insecticide, farmers can create buffer zones of conventional crops around GM fields to give harmful insects something to feed on, reducing the selection pressure to adapt to the anti-pest plant. Buffer zones would also deter cross-pollination and provide a refuge for harmless and beneficial insects.

"The benefits of biotechnology are many and include providing resistance to crop pests to improve production and reduce chemical pesticide usage, thereby making major improvements in both food quality and nutrition."

--World Health Organization Expert Consultation on Biotechnology and Food Safety, October 1996 [16]

"[T]here is no scientific justification for assuming this [the possibility of cross-pollination between GM plants and wild relatives] to be either undesirable or harmful in principle - each case needs consideration on its own merits."

--Dr. Phil Dale, GM plant scientist at the John Innes Centre, a U.K. agricultural research institute [17]

"The risks of modern genetic engineering have been studied by technical experts at the National Academy of Sciences and World Bank. They concluded that we can predict the environmental effects by reviewing past experiences with those plants and animals produced through selective breeding. None of these products of selective breeding have harmed either the environment or biodiversity."

--Jimmy Carter, 39th president of the United States [18]

References:
16: Quoted in "The Benefits of Biotechnology," www.biotechbasics.com/benefits.html.
17: "Genetically Modified Crops: Impact and Behavior of Transferred Genes," Biotechnology and Biological Sciences Research Council, U.K., January 1998.
18: "Who's Afraid of Genetic Engineering?" op-ed piece in The New York Times, 8/26/98.

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