Ecotoxicological screening of an e-liquid mixture using computational tools.

This article focuses on developing a novel framework to assess the potential ecological risks of chemicals in e-liquids used in electronic nicotine delivery systems (ENDS) as part of the U.S. Food and Drug Administration’s (USFDA) premarket tobacco product application (PMTA) environmental assessment requirements under the National Environmental Policy Act (NEPA). Using the U.S. Environmental Protection Agency’s (USEPA) Ecological Structure Activity Relationships (ECOSAR) program, the study predicted toxicity thresholds for chemicals in an exemplar e-liquid formulation and identified seven priority chemicals posing the greatest ecological concern. These chemicals’ environmental fate was further modeled with the USEPA Exposure and Fate Assessment Screening Tool (E-FAST) under hypothetical manufacturing release scenarios to estimate potential aquatic impacts. The framework offers a high-throughput, in silico screening method to efficiently prioritize chemicals for environmental risk assessment in complex mixtures like e-liquids, supporting regulatory compliance and product stewardship while acknowledging limitations related to predictive modeling and mixture interactions.