Investigation of Genotoxic Mechanisms of Etofenprox: Cytotoxicity, Micronucleus and Comet Analyses

Etofenprox is a synthetic pyrethroid pesticide widely used in agriculture, with significant ecotoxicological concern due to its potential for long-term persistence in the environment. This study aimed to evaluate the cytotoxic and genotoxic effects of etofenprox on Chinese hamster ovary (CHO) cells. Cytotoxicity was determined by measuring the cytokinesis-block proliferation index (CBPI) after exposure to various concentrations (1–800 µg/mL) of etofenprox. Genotoxicity was assessed using the micronucleus (MN) assay and alkaline comet assay. The results revealed significant reductions in CBPI, increases in MN frequency, and pronounced elevations in DNA damage parameters (tail length, % tail DNA, olive tail moment) at higher concentrations. These effects increased in a dose-dependent manner, particularly at concentrations ≥200 µg/mL, where the changes were statistically significant (p