Environmental risk assessment of GE plants under low-exposure conditions.

Andrew Roberts,Alan Gray,Yann Devos,Alan Raybould,Patrick Bigelow

doi:10.1007/s11248-013-9762-z

Abstract

The requirement for environmental risk assessment (ERA) of genetically engineered (GE) plants prior to large scale or commercial introduction into the environment is well established in national laws and regulations, as well as in international agreements. Since the first introductions of GE plants in commercial agriculture in the 1990s, a nearly universal paradigm has emerged for conducting these assessments based on a few guiding principles. These include the concept of case-by-case assessment, the use of comparative assessments, and a focus of the ERA on characteristics of the plant, the introduced trait, and the receiving environment as well as the intended use. In practice, however, ERAs for GE plants have frequently focused on achieving highly detailed characterizations of potential hazards at the expense of consideration of the relevant levels of exposure. This emphasis on exhaustive hazard characterization can lead to great difficulties when applied to ERA for GE plants under low-exposure conditions. This paper presents some relevant considerations for conducting an ERA for a GE plant in a low-exposure scenario in the context of the generalized ERA paradigm, building on discussions and case studies presented during a session at ISBGMO 12.

Highlights

Risk has historically been expressed as a function of two components: hazard and exposure
This paper presents some relevant considerations for conducting an environmental risk assessment (ERA) for a genetically engineered (GE) plant in a low-exposure scenario in the context of the generalized ERA paradigm, building on discussions and case studies presented during a session at ISBGMO 12
ERA is informed by the generation and testing of plausible risk hypotheses, which are derived from a risk scenario detailing the necessary steps or interactions that are required for the GE plant to cause harm in the environment

Summary

Introduction

Risk has historically been expressed as a function of two components: hazard and exposure. Potentially useful sources of information are discussed, as some of the information needed to adequately assess the environmental risk of low-exposure scenarios with a GE plant may already be available and come from existing knowledge and experience with the plant species, trait and receiving environment (OECD 2013). Since genetic material can move spatially and temporally through the transfer of pollen, seeds, or vegetative propagules, the assessment should consider relevant avenues and vectors for gene flow, together with factors that affect the probability of these processes These include knowledge on the presence of wild relatives in the receiving environment, the potential to hybridize with sympatric compatible relatives, and the ability of hybrids to persist or cross back into either parental species. Consideration should be given to whether or not the transgene in the GE plant is likely to alter the plant in a way which affects a control factor

Conclusions and recommendations

Findings

Limitations to the stepwise approach