title: Persistence and potential effects of complex organic contaminant mixtures in wastewater-impacted streams.
abstract: Natural and synthetic organic contaminants in municipal wastewater treatment plant (WWTP) effluents can cause ecosystem impacts, raising concerns about their persistence in receiving streams. In this study, Lagrangian sampling, in which the same approximate parcel of water is tracked as it moves downstream, was conducted at Boulder Creek, Colorado and Fourmile Creek, Iowa to determine in-stream transport and attenuation of organic contaminants discharged from two secondary WWTPs. Similar stream reaches were evaluated, and samples were collected at multiple sites during summer and spring hydrologic conditions. Travel times to the most downstream (7.4 km) site in Boulder Creek were 6.2 h during the summer and 9.3 h during the spring, and to the Fourmile Creek 8.4 km downstream site times were 18 and 8.8 h, respectively. Discharge was measured at each site, and integrated composite samples were collected and analyzed for >200 organic contaminants including metal complexing agents, nonionic surfactant degradates, personal care products, pharmaceuticals, steroidal hormones, and pesticides. The highest concentration (>100 μg L(-1)) compounds detected in both WWTP effluents were ethylenediaminetetraacetic acid and 4-nonylphenolethoxycarboxylate oligomers, both of which persisted for at least 7 km downstream from the WWTPs. Concentrations of pharmaceuticals were lower (<1 μg L(-1)), and several compounds, including carbamazepine and sulfamethoxazole, were detected throughout the study reaches. After accounting for in-stream dilution, a complex mixture of contaminants showed little attenuation and was persistent in the receiving streams at concentrations with potential ecosystem implications.
authors: U.S. Geological Survey , 3215 Marine Street, Boulder, Colorado 80303, United States.
authors: Larry B
authors: LB
authors: Barber
authors: Steffanie H
authors: SH
authors: Keefe
authors: Greg K
authors: GK
authors: Brown
authors: Edward T
authors: ET
authors: Furlong
authors: James L
authors: JL
authors: Gray
authors: Dana W
authors: DW
authors: Kolpin
authors: Michael T
authors: MT
authors: Meyer
authors: Mark W
authors: MW
authors: Sandstrom
authors: Steven D
authors: SD
authors: Zaugg
mesh_terms: D003120:Colorado; D017753:Ecosystem; D004784:Environmental Monitoring; D007484:Iowa; D009930:Organic Chemicals / Q000032:analysis*; D045483:Rivers / Q000737:chemistry*; D014865:Waste Disposal, Fluid; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D009930:Organic Chemicals; D062065:Wastewater; D014874:Water Pollutants, Chemical