The applicability of New Approach Methodologies (NAMs) in aquatic hazard and risk assessments of cosmetic ingredients: a case study of UV filters

Abstract Transitioning to Safe and Sustainable by Design (SSbD) in cosmetics requires reliable non-animal methods for early ingredient selection. This study proposes an approach that integrates New Approach Methodologies (NAMs) to screen for persistence, bioaccumulation, and toxicity (PBT), endocrine active substance (EAS), and environmental risk (predicted environmental concentration-to-predicted no-effect concentration (PEC/PNEC) ratio) to support the selection of less toxic ingredients for product formulation. A case study of nine organic ultraviolet (UV) filters commonly used in cosmetics, with exposure scenarios adapted to the Brazilian context, was used to demonstrate the applicability of the proposed approach. The selected UV filters were: bis-ethylhexyloxyphenol methoxyphenyl triazine (BEMT), butyl methoxydibenzoylmethane (BMD), diethylamino hydroxybenzoyl hexyl benzoate (DHHB), ethylhexyl methoxycinnamate (EMC), ethylhexyl salicylate (ES), ethylhexyl triazone (ET), octocrylene (OC), phenylbenzimidazole sulfonic acid (PSA), and tris- biphenyl triazine (TBT). For hazard predictions, PBT and endocrine activity were predicted using the freely available in silico tools QSAR Toolbox, VEGA, JANUS, Danish QSAR, T.E.S.T., and Endocrine Disruptome. In vitro data from the EPA ToxCast were included in the EAS evaluation. Using a majority consensus approach for integrating the in silico tools, ER activity was predicted only for ES. ToxCast data showed EAS potential for three of the four UV filters: OC and BMD (ER and AR antagonists), and ES as an ER agonist. Although results indicated some ingredients were toxic to aquatic life, under a conservative exposure scenario, PEC/PNEC ratios for water and sediment indicated acceptable environmental margins of exposure for PSA, BEMT, DHHB and TBT. In conclusion, hazard and risk assessments using NAMs data can be employed to identify UV filters of lower concern for aquatic environments and support the implementation of SSbD within the cosmetic industry.