Yeşilırmak Havzası'nda evsel ve endüstriyel atıksu arıtma tesislerinden kaynaklanan mikrokirleticilerin alıcı ortamdaki oluşumu ve yükü

The occurrence of micropollutants in the aquatic environment is an emerging topic. It is known that the wastewater treatment plants (WWTPs) are the main point sources of the micropollutants. With this regard, the purpose of the study is to determine the occurrence of micropollutants in the WWTPs, to detect the significant discharges, and to analyze the impacts of these discharges on the receiving bodies. A 2-year monitoring study was conducted in Yeşilırmak River Basin and 6 urban WWTPs (UWWTPs), 14 industrial WWTPs (IWWTPs), and related 22 surface water stations were analyzed for 45 priority substances defined by the EU Water Framework Directive (WFD) and 250 specific pollutants. The analysis results showed that the average concentrations of 22 and 38 micropollutants exceed the environmental quality standards (EQSs) in the effluents of UWWTPs and IWWTPs, respectively. Process contributions (PC) of these micropollutants were calculated and significant discharges were identified. The impacts of significant discharges were assessed by comparison of the pollution loads in the upstream and downstream of the related WWTP and results revealed that the Çorum UWWTP, Samsun OIZ, Turhal Sugar, and Özdemir Antimony Mine IWWTPs had the most significant effects on the downstreams, especially for metals. Additionally, the micropollutant removal efficiencies of 5 WWTPs were investigated, and the results showed that the WWTPs were not highly effective in micropollutants removal. This study provides comprehensive results to understand the conditions and effects of the WWTPs in the basin for competent authorities.