“The article describes a laboratory procedure which can be used for assessing the risks of transgenic plants on non-target organisms.”

The introduction of transgenic plants in crop production has lead to much political and social controversy. One major concern has been whether transgenic plants are a risk to the environment. Previous publications had claimed negative effects of transgenic insect-resistant plants on beneficial insects in laboratory experiments but not in the field. Most likely this paper is highly cited given the comprehensive and stepwise testing procedure which was used in order to determine whether plants expressing Bacillus thuringiensis pose a risk on an important predatory insect found in maize fields.

The article describes a laboratory procedure which can be used for assessing the risks of transgenic plants on non-target organisms. Although it provided no new discovery, it gives a holistic perspective on how to design and conduct risks assessment tests in the laboratory in order to gain enough meaningful information for deciding whether higher tier tests in the field are required.

Since 1996, insect-resistant transgenic crops expressing genes from Bacillus thuringiensis have been released into the field. The continuous expression of the insecticidal protein (Bt-toxin) in most plant tissues and throughout the growing season has raised concerns about the possible impact on insects that are not the target pest in the crop. In the study we investigated the effects of Bt-maize on three herbivores insects commonly found in a maize field that feed directly on the plant together with a third trophic organism, namely a predatory beneficial insect, that preys on these herbivores. By quantifying the amount of Bt-toxin found in each organism it was possible to determine the potential exposure of the organisms to the insecticidal protein. We found that exposure to the toxin varies according to the different feeding behaviors of the herbivore insects. Although the third trophic level predatory insect is potentially exposed to the Bt-toxin, no direct toxic effects were observed. This easy laboratory testing procedure can be used as a tool for predicting whether transgenic plants in the field could potentially have adverse effects on non-target organisms.

I was hired as a Postdoc in 2000 at the Swiss Federal Research Station for Agroecology and Agriculture (Agroscope FAL Reckenholz) where work on the risks of transgenic plants had been ongoing since the introduction of the technology into agricultural fields. The institute was one of the first to work in this area and since then has taken the lead on establishing methods and guidelines that are used in the risk assessment of transgenic plants.

This area of research has very important social and political implications as the use of transgenic plants has been restricted to only some areas of the globe, and the debate on whether they should be released in other areas is still ongoing. Establishing guidelines and conducting risk assessment research is necessary for providing the public with transparent information. Providing scientifically sound information to the layman is essential, given that this technology has been often portrayed as negative and harmful to the environment. A comparison between transgenic plants and the commonly accepted agricultural pest control methods is a requirement, in order that we can best judge if transgenic plants are more or less harmful to the environment.