Independent science now show that pests quickly develop resistance against toxic proteins produced by some GM plants. When first introduced to the market, the farmers where told that these new GM plants should result in less use of pesticides. Now after years of planting these toxic GM food plants several conventional farmers in various countries experience that they have to apply pesticides again. Not only do this mean that more toxic substances end up in the environment, water, air and food, but it mean that the allegations from the GMO industry does not hold water.
See the talk by Thomas Bøhn, director of research by Center for biodiversity.