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ICCVAM Biennial Report 2020-2021

Biennial Progress Report 2020-2021 Interagency Coordinating Committee on the Validation of Alternative Methods

Genetic Toxicity Screening Approach for Flavoring Chemicals

A variety of compounds are used as flavorings for electronic nicotine delivery systems, or e-cigarettes. Scientists in the FDA Center for Tobacco Products conducted a study (Hung et al. 2020) using alternative methods as prioritization tools to study the genotoxic mode of action of these compounds. The approach specifically examined clastogen-sensitive and aneugen-sensitive biomarkers of DNA damage in human TK6 cells. These biomarkers were aggregated through a supervised three-pronged ensemble machine learning prediction model to prioritize chemicals based on genotoxicity. In addition, in silico QSAR models were used to predict genotoxicity and carcinogenic potential. The parallel use of these predictive technologies to clarify modes of action for potential genetic damage might be helpful for screening chemicals in tobacco products.