Occurrence of selected pharmaceuticals in an agricultural landscape, western Lake Erie basin.

The occurrence of 18 commonly used pharmaceuticals was investigated in an agricultural area, which is primarily affected by runoff from agricultural fields and septic systems, on the coastline of Maumee Bay, within the western Lake Erie basin. Selected pharmaceuticals were detected in surface water, except clofibric acid and fluoxethine. The most frequently detected compounds were caffeine (88%), carbamazepine (57%) and paraxanthine (56%). Caffeine, carbamazepine, ibuprofen and paraxanthine were detected with maximum concentrations of 4.2, 1.2, 2.8 and 1.8 microg L(-1), respectively. However, no compound was detected in any sediment samples. In a field receiving biosolids application, pharmaceuticals were detected in the field tile drainage following biosolids application but not in soil. The occurrence of pharmaceuticals in surface water can be linked to the use of septic systems.