A perspective on problem formulation and exposure assessment of transgenic crops

Abstract: Risk assessment is a science-based decision making process. When risk assessmentfollows an established framework, it allows for transparency, predictability, and consistency inthe regulatory process. Problem formulation is a critical first stage in the risk assessment process;it involves 1) the characterization of the transgenic plant and receiving environment, 2) definitionof harm, 3) identification of potential exposure pathways or potential harm, and 4) establishmentof assessment endpoints to evaluate the potential for harm based on the plant’s characteristics.Risk to non-target organisms can be defined as the co-occurrence of hazard (or toxicity) andexposure. Exposure characterization has often been overlooked in the literature regarding the riskassessment of transgenic plants, with many recent publications focusing only on the hazardportion of the risk assessment equation. Exposure assessment informs the risk assessment andassists in the determination of which types of non-target organisms should be tested in hazardcharacterization. The purpose of risk assessment is to provide a framework for efficient decisionmaking,rather than to generally increase scientific knowledge; therefore data collection for riskassessment must be directed toward answering specific questions identified in the problemformulation stage.