Removal efficiency of pharmaceuticals in a full scale constructed wetland in East Ukraine
Résumé
Pharmaceuticals in surface water are a threat to drinking water supplies. The removal of 12 pharmaceuticals was investigated in a full scale constructed wetland processing hospital wastewaters in East Ukraine. Passive integrative samplers POCIS were used to monitor target compounds in the wastewater inlet and outlet at the beginning of the constructed wetland operation in 2012 and three years later in 2015. Pharmaceuticals were effectively removed; however, their removal efficiency differed among the compounds and years of the operation. An increase of removal efficiency was observed for androstenedione, carbamazepine, caffeine, diclofenac, estrone, ibuprofen, paracetamol, propranolol and triclosan with greater water residence time and an increase in macrophyte cover. Removal patterns of pharmaceuticals were discussed based on specific physical chemical properties of molecules, changes in the operational conditions of the constructed wetland and inlet pollutant concentrations. Further research is needed to fully understand how the maturation of constructed wetlands influences the removal of emerging contaminants from wastewater.