Extramural Research
Presentation Abstract
Grantee Research Project Results
Identifying Chemical Compounds from Wastewater Discharges
Susan T. Glassmeyer1, Edward T. Furlong2, Dana W. Kolpin3, Jeffery D. Cahill2, Steven D. Zaugg2, Stephen L. Werner2, Michael T. Meyer4, and David D. Kryak5
1Office of Research and Development, U.S. Environmental Protection Agency, Cincinnati, OH;
2U.S. Geological Survey, Denver, CO;
3U.S. Geological Survey, Iowa City, IA;
4U.S. Geological Survey, Lawrence, KS;
5Office of Research and Development, U.S. Environmental Protection Agency , Research Triangle Park, NC
The quality of drinking and recreational water is currently ascertained using indicator bacteria. The tests to analyze for these bacteria require a considerable length of time to complete and do not discriminate between human and animal fecal material sources. To shorten the time needed to test water quality and distinguish the fecal pollution source, chemicals found in human wastewater, such as pharmaceuticals, surfactants, and fecal sterols, were evaluated as tracers of human fecal pollution. These chemicals would have the advantage of requiring shorter analysis times than traditional microbiological techniques and can be selected to be human specific. At 10 locations, water samples were collected upstream and at 2 successive points downstream from a wastewater treatment plant. A treated effluent sample also was collected at each location. This longitudinal sampling scheme was used to estimate the persistence of the target compounds in streams. The water samples were extracted using either solid phase or liquid-liquid extraction and were analyzed using either liquid chromatography/mass spectrometry or gas chromatography/mass spectrometry. Of the 110 chemical analytes investigated in this project, 78 were found in at least one sample. Seventeen of the 110 compounds were classified as either a prescription or nonprescription pharmaceutical. Of these, 9 were found in at least 50 percent of the samples, and 13 were found in at least 10 percent of the samples. Although most concentrations of all of the compounds were in the range of 0.1 to 1.0 μg/L, in some of the more highly contaminated samples concentrations were in the range of 5-20 μg/L. The concentrations of the majority of the chemical compounds present in the samples generally followed an expected trend; they: (1) were non-existent or at only trace levels in the upstream samples; (2) had their maximum values in the wastewater effluent samples; and (3) declined in the two downstream samples. This research project indicates that these chemical analytes do have utility as tracers of human wastewater discharge. The correlation between the concentration of wastewater chemicals and incidence of illness is being investigated via a recreational water epidemiological study. The results of this study will determine if wastewater chemicals can be used as indicators of water quality.