Endocrine-disrupting effects of 24 colorants used in food contact materials: In vitro and in silico studies

Current research on endocrine-disrupting effects of colorants utilized in food contact materials (FCMs) ramains limited. This study investigated these effects through in vitro cell models and in silico toxicological models. A total of 24 synthetic colorants were collected from the Chinese market, including azo, anthraquinone, heterocyclic and fused-ring ketones, and phthalocyanines. Their endocrine-disrupting effects mediated by estrogen and androgen receptors were evaluated using an in vitro dual-luciferase reporter gene assay. Results showed no estrogenic or anti-estrogenic effects or androgenic activity in the colorants. However, three colorants, C.I. Pigment Red 177, C.I. Pigment Orange 71, and C.I. Pigment Blue 15, elicited anti-androgenic effects with 20 % relative inhibitory concentrations (RIC₂₀) of 13.08, 40.52, and 33.27 μg/mL, respectively. In addition, in silico toxicological models predicted the endocrine-disrupting activity of the 24 colorants, showing predictive accuracy ranging from 35 % to 100 % consistency with in vitro experimental outcomes. Molecular docking revealed strong binding affinity and mechanisms of interaction between three colorants and the human androgen receptor. In summary, this study combined in vitro experiments and in silico toxicological models to investigate the endocrine-disrupting effects of organic colorants with different structural types, providing new insights perspective on health risks associated with their use in FCMs.