Potential ecological and nontarget effects of transgenic plant gene products on agriculture, silviculture, and natural ecosystems: general introduction

On November 30 December 2,1992, a symposium was held at the University of Maryland. to discuss transgenic plant risk assessment issues for measurement and identification of potential ecological and nontarget organism effects. The goal was to identify available scientific information and highlight future research that will lead to useful test protocols for environmental risk assessments of transgenic plants. There have been more than 800 applications for testing genetically engineered organisms in the environment, most of them in the USA (The Gene Exchange 1993). Some applicants have asserted that because there have been no recorded adverse effects, what is the problem? There are several responses. First, virtually all releases have been on small plots of land conducted under conditions that minimize ecological response to transgenic plants and genes. Secondly, few data exist to describe the ecology of transgenic plants. Direct efforts to monitor pollen flow, to detect hybrids, to examine the life time of transgenic seeds in the soil, or to examine possible nontarget effects on the soil community, are but a few of the relevant risk assessment questions that have not been investigated. In most cases, field trial reports address product efficacy and most do not contain data on potential environmental effects (The Gene Exchange 1992). Catastrophic changes have not been observed but few would anticipate such events resulting from small-scale tests. By contrast, commercial applications will be on a very large scale. However, there are no data to support the extrapolation of data from smallto large-scale applications relative to risk assessment issues. Whether the cumulative effect of smaU trials (1-10 acres) is equivalent to a large-scale application (millions of acres) is unlikely.