The interest in natural surface-water treatment techniques such as bank filtration and artificial ground water replenishment has increased with the growing worldwide need for clean drinking water. After detecting a number of pharmaceutical residues in groundwater samples from a bank filtration site in Berlin, Germany, the research on these compounds has focused on investigating their transport behavior during the infiltration process. In the studies presented in this paper, the fate of six pharmaceutical residues detected at concentrations up to the µg/L-level in Berlin’s surface waters was investigated. During bank filtration, the analgesic drugs diclofenac and propyphenazone, the antiepileptic drugs carbamazepine and primidone and the drug metabolites clofibric acid and 1-acetyl-1-methyl-2-dimethyl-oxamoyl-2-phenylhydrazide (AMDOPH) were found to leach from the surface water into the groundwater aquifers. They also occur at low ng/Lconcentrations in the receiving water-supply wells. Other compounds namely the antiphlogistic drug indometacine and the blood regulating drug bezafibrate which are also detected at concentrations up 100 ng/L in the surface water are efficiently removed by bank filtration. Thus, they have not been detected downstream of the first two monitoring wells. In conclusion, bank filtration was found to decrease the concentrations of some drug residues (e.g. of diclofenac, carbamazepine) or even to remove selected compounds (e.g. bezafibrate, indometacine). However, a complete removal of all potential pharmaceutical residues by bank filtration cannot be guaranteed.
Fate and transport of pharmaceutical residues during bank filtration