Lethal and sublethal exposure of Hemichromis bimaculatus (Gill, 1862) to malachite green and possible implications for ornamental fish

Malachite green (MG) is a triphenylmethane dye that is widely used in aquaculture as a fungicide, bactericide, ectoparasiticide, and antiprotozoal. There is great debate regarding the potential for this compound to trigger adverse effects. Here, we review the previous findings and then evaluate the lethal and sublethal effects of MG in the species Hemichromis bimaculatus (jewelfish). The lethal concentration for 50% of the fish in 96 h was 1 mg/L. We observed a dose-dependent increase in the percentage of fish mortality as well as physical and behavioral changes. We further found that the highest tested sublethal dose significantly increased the DNA damage index identified using the comet assay (74.97 ± 13.8 at a significant level of P