Effects of heavy metal pollution on hepatosomatic ındex and vital organ histology in Alburnus mossulensis from Karasu River

In this study, histological effects of water pollution to freshwater cyprinid, Alburnus mossulensis, was investigated. Water, sediment, and fish samples were taken from four stations in Karasu River Erzurum, Turkey between June and September in 2015? 2016. In water and sediment samples, the concentrations of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Sr, and Pb were detected. Histopathological changes in gill, liver, and kidney tissues were determined by degree of tissue change DTC , and hepatosomatic index HSI was calculated. The mean concentrations of heavy metals in water and sediment samples were lower at station 4. The trend of some metal contents found in the fish was in increasing order of Zn < Cu < Cr < Pb. The observations on histopathology included cellular degeneration, congestion, dilatation, vacuolization, edema, vasodilatation, hyperplasia, hypertrophy, infiltration, melanomacrophage aggregates, glomerulopathy, fibrosis, and necrosis. It was observed that the DTC and HSI values in fish varied significantly from station to station. The results showed that the higher severity of histopathological alterations in the fish tissues was strongly correlated with agricultural and domestic activities in the area.