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1H a/b/c - Pesticides, pharmaceuticals, perfluoroalkylated substances, antibiotics (WEP/33) Removal of pharmaceuticals during riverbank filtration. Sacher, Frank1, Gabriel, Sabine1, Metzinger, Melanie1, Wenz, Michael1, Brauch, Heinz-Juergen1, 1 DVGW-Technologiezentrum Wasser, Karlsruhe, Baden-Württemberg, Germany ABSTRACT- Nowadays, the occurrence of pharmaceutical residues in the aquatic environment is a well-recognized problem. As in Germany part of the water suppliers use bankfiltrated river water for drinking water production the behaviour of pharmaceuticals during the riverbank filtration process is of special interest. Hence, laboratory-scale experiments were performed using so-called testfilters to simulate the microbial degradation of selected pharmaceuticals (analgesics, lipid-regulation agents, betablockers, antiepileptics, x-ray contrast media, and antibiotics) during underground passage. These experiment were done using water from river Rhine in a closed-loop apparatus. The water was spiked at low concentration levels (10 Key words: biodegradation, pharmaceuticals, riverbank filtration |
g/L) with the compounds under investigation and pumped for several days over a carrier material made of sintered porous glass beads. The system was permanently aerated with ambient air and the concentration levels of the spiked pharmaceuticals were regularly monitored. The results obtained from these laboratory-based experiments were compared to real-life data from waterworks along the lower river Rhine. The testfilter experiments yielded a different behaviour of the pharmaceuticals under investigation. Most pharmaceuticals were eliminated within less than three weeks, indicating a good biodegradability of these compounds, but others, like carbamazepine, diclofenac, sulfamethoxazole and most of the x-ray contrast media proved to be persistent under the testfilter conditions. In most cases these results correspond very well to the results of long-time measurements of river water and bankfiltrated water at waterworks along river Rhine where most of the pharmaceuticals that proved to be persistent in the testfilter experiment were also found in the raw water, i.e. the bankfiltrated river water.