Bt Crops Pose Little Threat to Non-Target Organisms

October 19, 2005, Lanham, Md.—Environmental Entomology, an Entomological Society of America journal has just published the results of 11 field studies of the impact of Bt crops on non-target organisms. These field studies, published in 13 research papers in the October issue of the journal, represent the most comprehensive, long-term scientific assessment of this issue to date.

The effect of Bt technology on non-target organisms has been one aspect of the wide-ranging debate over transgenic crops. These crops, which have been in commercial production since 1996, are protected from specific insect pests with insecticidal proteins derived from the bacterium Bacillus thuringiensis (Bt).

The results of the new studies provide extensive data to support the conclusion reached by regulators when these crops were first commercializedthat Bt cotton and Bt corn pose little, if any, threat to organisms not targeted by the Bt proteins. These studies also bear out one of the environmental benefits of Bt cropsthe reduction in the use of insecticides with broad-spectrum activity. These commonly used insecticides not only affect a wide range of pests but also have been shown to be more damaging to non-target organisms.

The field studies, conducted in the United States and Australia, focused on the longer-term assessment of potential non-target effects of transgenic Bt cotton and corn. The research encompassed two varieties of crops (upland cotton and hybrid corn) which collectively produce five insecticidal proteins, and involved the evaluation of a wide breadth of non-target arthropods. With one exception, studies were conducted over a minimum of three site-years in either controlled, moderate-sized research plots or in commercial fields subject to typical grower production practices. The majority of studies were conducted for three years or more.

Publication of these papers inaugurates a new subject area in Environmental Entomology entitled “Transgenic Plants and Insects.”  

"This new subject area allows us to explore issues in agricultural biotechnology," said Dr. E. Alan Cameron, the journal’s editor-in-chief. "In this inaugural section, we present a unique body of research that shows that Bt crops have little effect on non-target organisms, especially compared to the alternative use of insecticides with broad-spectrum activity, which can be many times more damaging to the non-target arthropod community.”

“Future topics in this subject area will include all aspects of the development, application, and assessment of transgenic technology in pest management and its environmental impact,” Cameron added.

Environmental Entomology, one of four scientific, peer-reviewed journals published by the Entomological Society of America, covers a wide variety of subjects within the area of insects’ interaction with the biological, chemical, and physical aspects of their environment. Published bimonthly, the current issue (October 2005, Vol. 34, No. 5) is available at

Founded in 1889, ESA is a non-profit organization committed to serving the scientific and professional needs of more than 5,700 entomologists and individuals in related disciplines. ESA's membership includes representatives from educational institutions, government, health agencies, and private industry.