title: Contaminants of Emerging Concern: Mass Balance and Comparison of Wastewater Effluent and Upstream Sources in a Mixed-Use Watershed.
abstract: Understanding the sources, transport, and spatiotemporal variability of contaminants of emerging concern (CECs) is important for understanding risks and developing monitoring and mitigation strategies. This study used mass balances to compare wastewater treatment plant (WWTP) and upstream sources of 16 CECs to a mixed-use watershed in Minnesota, under different seasonal and hydrological conditions. Three distinct CEC groups emerged with respect to their source proportionality and instream behavior. Agricultural herbicides and daidzein inputs were primarily via upstream routes with the greatest loadings and concentrations during high flows. Trimethoprim, mecoprop, nonprescription pharmaceuticals, and personal care products entered the system via balanced/mixed pathways with peak loadings and concentrations in high flows. Carbaryl, 4-nonylphenol, and the remaining prescription pharmaceuticals entered the system via WWTP effluent with relatively stable loadings across sampling events. Mass balance analysis based on multiple sampling events and sites facilitated CEC source comparisons and may therefore prove to be a powerful tool for apportioning sources and exploring mitigation strategies.
authors.affiliation: University of Minnesota , Water Resources Center, 1985 Buford Ave., St Paul, Minnesota 55108, United States.
authors.forename: David J
authors.initials: DJ
authors.lastname: Fairbairn
authors.affiliation: University of Minnesota , Civil, Environmental, and Geo- Engineering, 500 Pillsbury Drive SE, Minneapolis, Minnesota 55455, United States.
authors.forename: William A
authors.initials: WA
authors.lastname: Arnold
authors.affiliation: University of Minnesota , Department of Soil, Water, and Climate, 1902 Dudley Ave, Saint Paul, Minnesota 55108, United States.
authors.forename: Brian L
authors.initials: BL
authors.lastname: Barber
authors.affiliation: University of Minnesota , Water Resources Center, 1985 Buford Ave., St Paul, Minnesota 55108, United States.
authors.forename: Elizabeth F
authors.initials: EF
authors.lastname: Kaufenberg
authors.affiliation: United States Department of Agriculture, Agricultural Research Service, 1991 Upper Buford Circle, University of Minnesota , Saint Paul, Minnesota 55108, United States.
authors.forename: William C
authors.initials: WC
authors.lastname: Koskinen
authors.affiliation: University of Minnesota , Civil, Environmental, and Geo- Engineering, 500 Pillsbury Drive SE, Minneapolis, Minnesota 55455, United States.
authors.forename: Paige J
authors.initials: PJ
authors.lastname: Novak
authors.affiliation: United States Department of Agriculture, Agricultural Research Service, 1991 Upper Buford Circle, University of Minnesota , Saint Paul, Minnesota 55108, United States.
authors.forename: Pamela J
authors.initials: PJ
authors.lastname: Rice
authors.affiliation: University of Minnesota , Water Resources Center, 1985 Buford Ave., St Paul, Minnesota 55108, United States.
authors.forename: Deborah L
authors.initials: DL
authors.lastname: Swackhamer
mesh_terms: D004784:Environmental Monitoring / Q000379:methods*; D005843:Geography; D008910:Minnesota; D014865:Waste Disposal, Fluid; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis*; D018508:Water Purification
chemical_list: D062065:Wastewater; D014874:Water Pollutants, Chemical