Immunotoxicity of 1-methyl-3-octylimidazolium bromide on brocarded carp (Cyprinus carpio L.)

In the present study, the immunotoxicity of 1-methyl-3-octylimidazolium bromide ([C8mim]Br) on brocarded carp was evaluated by an acute exposure of 100–300 mg L−1 of [C8mim]Br for 7 days. The results showed 300 mg L−1 of [C8mim]Br exposure caused activity inhibition of specific and non-specific immune systems, mainly including IgM level, lysozyme activity, and complement C3 content, while 100 mg L−1 of [C8mim]Br activated fish immune system during the early periods of exposure (2–5 days). This result indicates that [C8mim]Br has immunotoxicity on brocarded carp. Additionally, histological observation revealed that 300 mg L−1 of [C8mim]Br-exposure led to remarkable damages to the hepatopancreas, kidney, and spleen of brocarded carp after 7 days of [C8mim]Br treatment, although not only change in kidney and spleen somatic indexes was found, but also no swelling or hemorrhage of carp viscera occurred.

► The ionic liquid [C8mim]Br has immunotoxicity on brocarded carp.
► 300 mg L−1 of [C8mim]Br exposure caused activity inhibition of specific and non-specific immune systems, mainly including IgM level, lysozyme activity, and complement C3 content.
► [C8mim]Br-exposure led to remarkable damages to the hepatopancreas, kidney, and spleen of brocarded carp.