Pomeranian wastewater treatment plants as hot-spots of antibiotic resistance: the impact on the coastal waters of the Baltic sea

Wastewater treatment processes are monitored mainly in terms of biogenic substances removal efficiency. Only recently they started to be perceived as a potential sources of pharmaceutical residues to their recipients the and hot-spots for antibiotic resistance dissemination among bacteria. The scale of the problem has not been fully investigated and understood – missing data on the pharmaceuticals consumption, unidentified and dispersed point sources and non-unified sampling strategy of monitoring programs have been identified as the examples of problematic areas. I n scope of project REPHIRA (Reduction of Pharmaceutical Emissions from Dispersed Point Sources in Rural Areas), financed from the Interreg Baltic Sea Region Seed Money, the cooperation has been established between five partners located in the Baltic Sea catchment area: Poland, Germany, Denmark, Sweden and Finland. In order to fulfill the knowledge gap, a preliminary study was conducted by Polish partner on four wastewater treatment plants (WWTPs) localized in the coastal area in northern Poland. Objects differ in terms of load, people equivalent, treatment technology and the recipient of WWTP effluent. The amount of human gut related indicator organism, E. coli has been estimated in raw and treated wastewater, as well as in the receiver, using classical microbiology approach and cultivation method. Additionally, the bacterial resistance to cefotaxime – an antibiotic belonging to third-generation cephalosporin family – has been tested.