Determination of heavy metal accumulation in water and fish tissues in Asarsuyu Stream

Asarsuyu Stream, one of the major river resources of the Büyük Melen Basin in the Western Black Sea Region, is under severe urban and industrial pollution pressure.In this study, it was aimed to determine water quality depending on physical and chemical parameters such as temperature, dissolved oxygen, salinity, EC, pH, various anions and cations and heavy metals in Asarsuyu Stream as well as to determine heavy metal accumulation in liver and gill tissues of fish species Squalius pursakensis and Barbus tauricus.Within the scope of the present study, sampling of water and fish was carried out seasonally in February-October 2018 at three different points of Asarsuyu Stream.The results indicated that Asarsuyu Creek was in Class 4 (Very Polluted) water quality class in terms of physical and inorganic chemical parameters.Nitrogenous compounds and dissolved oxygen in the water were found to be at critical values.It was determined that aluminum, iron and zinc were the most abundant pollutant metals in the water; however, the concentration of these metals did not reach lethal levels for living beings. In addition, it was determined that the amount of iron and aluminum was high in the liver tissue, mercury approached the limit values and cadmium and lead exceeded these values in the fish species studied. In order to control pollution in the area, it is considered appropriate to prevent especially the discharge of urban and industrial wastewater to Asarsuyu Stream, to ensure effective control of industrial plants and treatment plants, and to limit the use of fertilizers and pesticides.