Genotoxic evaluation of the Ergene River, Turkey, on mosquito fish, Gambussia affinis (Baird and Girard, 1853) using the piscine micronucleus assay

The Ergene River is located in the Thrace Region of Turkey and is polluted by industrial and municipal waste. In the present study, we investigated the genotoxic and cytotoxic effects of water samples on Gambussia affinis in vivo using the piscine micronucleus (MN) test. Fish were exposed to 50, 100, 150 and 300 mL L-1 of water samples for 24 hrs, and MN, nuclear abnormalities (NA), polychromatic-normachromatic erythrocytes (PCEs/NCEs), and apoptotic erythrocytes were evaluated. In addition, water samples were analysed to determine the concentrations of the heavy metals. The results showed that MN, NA, and apoptosis frequencies significantly increase at all concentrations compared to the control. A significant correlation was found between genotoxicity endpoints and the concentration of water samples. The PCE-NCE ratio was significantly decreased at all treatments. The metal content of river water was not associated with the increase in the seasonal frequency of genotoxicity endpoints. The results indicated that the Ergene River has genotoxic and cytotoxic effects on erythrocytes of G. affinis in an in-vivo piscine MN test that could be due to organic and inorganic effluents.