Core and Supplementary Studies to Assess the Safety of Genetically Modified (GM) Plants Used for Food and Feed




genetically modified, safety assessment, food and feed, hazard, exposure, risk, core studies, supplementary studies


Genetically modified (GM) plants used for food and feed have an established history of safe use over more than 25 years of their commercialization. Developers and regulatory authorities have accumulated extensive experience in evaluating their safety over time. The studies required for the safety assessment of GM plants used for food and feed should now be re-defined to leverage this experience and increased scientific knowledge. This paper, a companion paper for Waters et al. also published in this issue, presents a systematic approach for the safety assessment of newly expressed proteins (NEPs) in GM plants by evaluating the two components of risk: hazard and exposure. Although the paper focuses on NEPs, the principles presented could also apply to other expression products that do not result in a NEP. A set of core studies is recommended, along with supplementary studies, if needed, to evaluate whether the GM plant poses risk. Core studies include molecular and protein characterization and hazard identification encompassing toxicity and allergenicity. In the absence of hazard, core studies are sufficient to conclude that GM plants are as safe as their conventional counterparts. Depending on the GM trait and intended use, supplementary studies should be performed to characterize hazard and exposure when a hazard is identified. Problem formulation should be used to identify hypothesis-driven supplementary studies. Acute toxicity studies, compositional assessment, and dietary exposure assessment are recommended to be hypothesis-driven supplementary studies. Further discussion on the current food and feed safety assessment landscape for GM plants and the use of problem formulation as a tool for identifying supplementary studies can be found in the companion paper [62].

doi: 10.21423/jrs-v09i1brune


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