Emerging Contaminants in Coastal Landscape Park, South Baltic Sea Region: Year-Round Monitoring of Treated Wastewater Discharge into Czarna Wda River

In response to the European Union’s revised Urban Wastewater Treatment Directive, which mandates enhanced monitoring and advanced treatment of micropollutants, this study was conducted. It took place within the Coastal Landscape Park (CLP), a Natura 2000 protected area in northern Poland. The focus was on the municipal wastewater treatment plant in Jastrzębia Góra, located in a region exposed to seasonal tourist pressure and discharging effluent into the Czarna Wda River. A total of 90 wastewater samples were collected during five monitoring campaigns (July, September 2021; February, May, July 2022) and analysed for 13 pharmaceuticals and personal care products (PPCPs) using ultra-high-performance liquid chromatography tandem mass spectrometry with electrospray ionisation (UHPLC-ESI-MS/MS). The monitoring included both untreated (UTWW) and treated wastewater (TWW) to assess the PPCP removal efficiency and persistence. The highest concentrations in the treated wastewater were observed for metoprolol (up to 472.9 ng/L), diclofenac (up to 3030 ng/L), trimethoprim (up to 603.6 ng/L) and carbamazepine (up to 2221 ng/L). A risk quotient (RQ) analysis identified diclofenac and LI-CBZ as priority substances for monitoring. Multivariate analyses (PCA, HCA) revealed co-occurrence patterns and seasonal trends. The results underline the need for advanced treatment solutions and targeted monitoring, especially in sensitive coastal catchments with variable micropollutant presence.