Problem formulation and hypothesis testing for environmental risk assessments of genetically modified crops

Abstract

Environmental risk assessments can provide high confidence of minimal risk by testing theories, "risk hypotheses", that predict the likelihood of unacceptable harmful events. The creation of risk hypotheses and a plan to test them is called problem formulation. Effective problem formulation seeks to maximize the possibility of detecting effects that indicate potential risk; if such effects are not detected, minimal risk is indicated with high confidence. Two important implications are that artificial test conditions can increase confidence, whereas prescriptive data requirements can reduce confidence (increase uncertainty) if they constrain problem formulation. Poor problem formulation can increase environmental risk because it leads to the collection of superfluous data that may delay or prevent the introduction of environmentally beneficial products.

Assessment of risk of insect-resistant transgenic crops to nontarget arthropods

“…In our approach, the problem formulation stage is designed to identify the areas of greatest concern or uncertainty concerning ecological risks, and to define the scope of the risk assessment by generating testable scientific hypotheses that are subsequently addressed in the analytical phase of the risk assessment 8,13,14 . The information that is considered during problem formulation takes many forms, including published scientific literature, expert opinion, stakeholder deliberations and data developed by the registrants and submitted to the regulatory authority as part of the registration dossier.…”

“…This information establishes the level of 'familiarity' (that is, the similarities in ecologically relevant characteristics) between the IRGM crop and nontransformed crop [15][16][17] and, together with the related concept for food of 'substantial equivalence' , serves as a starting point to focus the ERA process on potential stressors of concern 18,19 . If substantial equivalence and familiarity are established, the ERA can proceed with emphasis on narrowly defined, stressor-mediated effects that arise from the expressed trait in the IRGM crop (e.g., a Bt protein) 14,20 . In cases where substantial differences other than those directly related to the expressed trait are detected, these characteristics become additional potential stressors that also need to be evaluated, following the same tiered approach that we outline.…”

Environmental Risk Assessment of Genetically Modified Crops: General Principles and Risks to Non-target Organisms

“…The hypothesis could be tested by mathematical modelling of the dispersal of the chemical under the proposed use, and confidence in the risk assessment could be increased by making conservative assumptions about the values of parameters in the model. If the risk hypothesis is not falsified after testing under highly conservative conditions, there is high confidence that the use of the chemical presents negligible risk to the endangered species (Raybould 2006).…”

“…Collection of additional data could always be justified because it would provide "more evidence to prove safety". Hypothesis testing provides a clear criterion to judge the value of additional data: unless the additional data offer a more rigorous test of the risk hypothesis than existing data, and thereby increase certainty of the risk assessment, they are superfluous (Raybould 2006).…”

“…If delay can increase risk, no study can be free from risk, and requirements for data to assess the risk of an action must be balanced with the loss of potential benefits of that action while the data are collected. Therefore to minimise environmental risk, problem formulation should devise risk hypotheses that can be rigorously tested with the minimum need to acquire additional data (Raybould 2006).…”