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At the NWQL, Pharmaceuticals are measured as trace compounds present in filtered water samples that are indicative of anthropogenic influence upon water bodies. High resolution chromatography coupled to sophisticated mass spectrometers can provide sub-parts per billion reporting levels for 100’s of pharmaceuticals in a single analysis. The NWQL uses a high-performance liquid chromatography/tandem mass spectrometry (LC/MSMS) method to sensitively and specifically determine over 110 human-use pharmaceuticals and related organic compounds at concentrations as low as a few nanograms per liter (parts-per-trillion). The method has been applied to thousands of surface and groundwater samples, wastewater influent and effluent samples, source and treated drinking water samples, and other water samples. The official report that documents this method and its  performance characteristics is freely available aat:

Numerous reports that use this and other related methods to measure the presence and distribution of pharmaceuticals and other emerging contaminants are assembled as part of the U.S. Geological Survey’s Toxic Substances Hydrology Program’s Contaminants of Emerging Concern Investigation, which is described at:

Specific reports from that investigation can be searched out at the Investigation’s  bibliography website: