Investigation of lethal range concentration and median lethal concentration of Hexaflumuron in common carp fishes (Cyprinus carpio)

Hexaflumuron is a pesticide used in farms to control insects and has been introduced as a new and effective insecticide to control rice stemborer. This study investigated lethal range concentration and median lethal concentrations of hexaflumuron in common carp (Cyprinus carpio) for the first time. For this purpose, the fishes in 6 treatments received concentrations of 0, 1.25, 2.5, 5, 10 and 25 mg/l hexaflumuron to determine the lethal range concentration and fish mortality was recorded in each treatment at 24, 48, 72 and 96 hours. Then, to determine the median lethal concentration the fishes received 0, 6, 7, 8 and, 9 mg/l hexaflumuron in 5 treatments with 3 replications and the fish mortality was recorded at 24, 48, 72 and 96 hours. The data obtained from the median lethal concentration were analyzed by probit statistical analysis and the ​​(LC5-95), No Observed Effect Concentration (NOEC) and Lowest Observed Effect Concentration (LOEC) were calculated. In this study, the median lethal concentrations of hexaflumuron at 24, 48, 72 and 96 hours were obtained 9.925, 8.395, 8.075, and 7.428 mg/l respectively. Also, NOEC and LOEC were calculated as 0.7428 and 28.42 mg/l. Behavioral and physical symptoms such as lethargy, hyperemia at the base of the fins, red eyes, very slow movements and swimming, vertical swimming, lying on the floor and finally death were observed in fishes. The results of this study showed that hexaflumuron has a moderate degree of toxicity for common carp and fish mortality increases following increasing concentration and exposure to hexaflumuron consumption.