Environmental Risk Assessment

In many world regions, regulatory frameworks are in place to ensure that all precommercial genetically modified (GM) crops are evaluated for potential impacts on human health, animal health and the environment according to established standards of risk assessment and current scientific knowledge before authorizations for import or planting are granted. The environmental risk assessment for GM crops follows the same fundamental principles as other risk assessment schemes, i.e. risk is a function of hazard and exposure. However, one of the main differences that sets GM crop risk assessment apart is that it is highly dependent on the crop and the introduced trait; hence, a case-by-case approach is required. For many crop/trait combinations, the assessment is based on a comparison with an appropriate conventional non-GM crop. If agronomic/phenotypic and compositional/nutritional equivalence between the GM crop and its non-GM counterpart is demonstrated, the environmental risk assessment can focus on what is different. For products with no appropriate comparator, further testing or a non-comparative-based evaluation may be required. The goal of the environmental risk assessment is to systematically collect information to support decision making. This is achieved by focusing on end points that are clearly defined and aligned with environmental management goals defined by public policy. A well-constructed risk assessment should follow a logical progression or 'tiered approach', where all information available at a given time is gathered and assessed to determine what, if any, additional data must be collected to reach satisfactory risk conclusions. The risk assessment provides regulators with information that allows them to make knowledge based decisions about the GM crop. Final authorizations for commercialization, whether for import or cultivation, take into account the outcome of the environmental risk assessment, a formal assessment of food and feed safety, and in certain cases also consider political, economic and societal factors. Although the details of the risk assessment frameworks for GM crops vary from country to country, the general principles upon which they are based are comparable. Since 1996, over 100 GM crop/trait combinations have been placed on the market without negative environmental impacts, demonstrating the robustness of existing frameworks. This chapter reviews the main principles and regulatory aspects of the environmental risk assessment of GM crops.