Occurrence of Antibiotics, Pharmaceuticals and Sterols at Select Surface and Wastewater Sites in Iowa

Interest has been expressed in tracing possible sources of contamination (e.g. from human or other waste) by using compounds such as pharmaceuticals, caffeine, and sterols in waste as potential source markers. This pilot study was designed to identify and measure a limited set of compounds in aqueous environmental samples to determine possible relations between these compounds to animal and human activity. Field samples were collected quarterly for one year from three stream basins – a control stream; a stream potentially affected by concentrated swine production, and a stream potentially affected by concentrated cattle production. In addition, samples were collected from two wastewater treatment plant discharges in an urban area. Samples were analyzed for 34 organic wastewater compounds. A preliminary examination of the data suggests that caffeine, acetaminophen, ibuprofen, trimethoprim, sulfamethoxazole, bis(2-ethylhexyl)phthalate, and diethyl phthalate, have the strongest relation to human activity.