GM crop acreage has increased rapidly world-wide since the introduction of GM crops in 1996, driven primarily by cotton, corn and soybeans.  By 2008, roughly 10% of cropland was planted in GM crops.  The adverse effects, such as rapid development of Bt resistance, have not materialized.  So far, the only unexpected effects have been beneficial.  For example, many grains and nuts, including peanuts, are often contaminated by toxic compounds, called mycotoxins, made by fungi that follow boring insects into the plants.  Two of these, fumonisins and aflatoxin, are extremely toxic to people and animals.  Bt corn, however, shows as much as a 90% reduction in mycotoxin levels because the fungi that follow the boring insects into the plants can’t get in.  No insect holes, no fungi, no mycotoxin.  It has also been reported that planting Bt crops might well reduce insect pressure in other crops growing nearby.  Bt cotton has been widely planted in Asia.  Analysis of the population dynamics of the target pest, the cotton bollworm, show that Bt cotton not only controls the target pest, cotton bollworm, on transgenic cotton designed to resist this pest but also reduces its presence on other host crops and decreases the need for insecticide sprays in general (Science 19 September 2008). 

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