which were filled with approximately 200 g of wet sediment and 600 mL of artificial river water. The system was equilibrated for one week before the supernatant was replaced with artificial river water that was spiked with a mixture of pharmaceuticals as described below. The bottles were continuously aerated with pressurized air and kept in the dark at a temperature of 15◦C. A daily dose of 200 g ofd-glucose was added to each bottle to avoid a carbon limitation of the system.