Determination of Nuclear Abnormalities in Peripheral Erythrocytes of the Frog Pelophylax ridibundus (Anura: Ranidae) sampled from Karasu River Basin (Turkey) for Pollution Impacts

Karasu River, which is the only river in the Erzurum plain, is the source of the river Euphrates (Eastern Anatolia of Turkey). The river is in a serious environmental situation as a result of pollution by agricultural and industrial sewage and domestic discharges. The present study aims to evaluate genotoxic effects of toxic metals in marsh frog, Pelophylax ridibundus collected from two contaminated wetlands environments of the Karasu River Basin, in comparison with frogs from one non-polluted reference site. Heavy metal concentrations in surface water of the river were determined. Genotoxicity assays such as micronucleus (MN) and other nuclear abnormalities (NA) were carried out on the frogs studied. MN and NA (kidney-shaped nucleus, notched nucleus and lobed nucleus) were assessed in peripheral blood erythrocytes of the frog. A significant elevation in MN and NA frequencies was observed in frog collected from the polluted sites compared with those from the reference site. Results of the current study suggest that there is a close realtion between increasing of erythrocytic nuclear abnormalities and environmental contamination. High concentrations of heavy metals have a potential genotoxic effects, and the toxicity is possibly related to industrial, agricultural and domestic activities.