Oxidative stress, genotoxicity and cytotoxicity of 1-methyl-3-octylimidazolium chloride on Paramisgurnus dabryanus

•Acute toxicity test result showed that [C8mim]Cl had higher toxicity effect to P. dabryanus.•Biochemical analysis results showed that [C8mim]Cl could induce oxidative stress in fish.•Comet assay results showed that [C8mim]Cl induced obvious genotoxicity in fish.•Apoptosis analysis results showed that [C8mim]Cl induced obvious cytotoxicity in fish.•Toxicity effects of [C8mim]Cl to fish were obvious dose-t and time-effect relationships.

This study evaluated the toxicity of 1-methyl-3-octylimidazolium chloride ([C8mim]Cl) on Paramisgurnus dabryanus by enzyme analysis, comet assay, and apoptosis analysis. The study showed that [C8mim]Cl had an obvious toxic effect inducing oxidative stress, genotoxicity, and cytotoxicity to fish liver cells. [C8mim]Cl also induced changes in the activities of superoxide dismutase and catalase, and the glutathione content and malondialdehyde level in fish exposed at 20–80 mg L−1. With increased exposure concentration and time, the four antioxidant enzyme activities, three different comet parameters and apoptosis rates of tested cells were significantly increased, with significant differences (P < 0.05 or P < 0.01) observed between control group and each treatment group. This study shows that [C8mim]Cl could be a threat to aquatic organism health when accidentally released into aquatic ecosystems.