title: Application of surrogates, indicators, and high-resolution mass spectrometry to evaluate the efficacy of UV processes for attenuation of emerging contaminants in water.
abstract: In response to water scarcity, strategies relying on multiple processes to turn wastewater effluent into potable water are being increasingly considered by many cities. In such context, the occurrence of contaminants as well as their fate during treatment processes is a major concern. Three analytical approaches where used to characterize the efficacy of UV and UV/H2O2 processes on a secondary wastewater effluent. The first analytical approach assessed bulk organic parameters or surrogates before and after treatment, while the second analytical approach measured the removal of specific indicator compounds. Sixteen trace organic contaminants were selected due to their relative high concentration and detection frequency over eight monitoring campaigns. While their removal rate ranges from approximately 10 to >90%, some of these compounds can be used to gauge process efficacy (or failure). The third analytical approach assessed the fate of unknown contaminants through high-resolution time-of-flight (TOF) mass spectrometry with advanced data processing and demonstrated the occurrence of several thousand organic compounds in the water. A heat map clearly evidenced compounds as recalcitrant or transformed by the UV processes applied. In addition, those chemicals with similar fate were grouped together into clusters to identify new indicator compounds. In this manuscript, each approach is evaluated with advantages and disadvantages compared.
authors.affiliation: Department of Chemical and Environmental Engineering, University of Arizona, 1133 James E. Rogers Way, Tucson 85721, AZ, USA. Electronic address: smerel@email.arizona.edu.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Merel
authors.affiliation: Department of Chemical and Environmental Engineering, University of Arizona, 1133 James E. Rogers Way, Tucson 85721, AZ, USA. Electronic address: tanumol@email.arizona.edu.
authors.forename: Tarun
authors.initials: T
authors.lastname: Anumol
authors.affiliation: Department of Chemical and Environmental Engineering, University of Arizona, 1133 James E. Rogers Way, Tucson 85721, AZ, USA. Electronic address: minkyupark@email.arizona.edu.
authors.forename: Minkyu
authors.initials: M
authors.lastname: Park
authors.affiliation: Department of Chemical and Environmental Engineering, University of Arizona, 1133 James E. Rogers Way, Tucson 85721, AZ, USA. Electronic address: chemosphere.snyder@gmail.com.
authors.forename: Shane A
authors.initials: SA
authors.lastname: Snyder
mesh_terms: D002853:Chromatography, Liquid; D006861:Hydrogen Peroxide / Q000737:chemistry*; D016877:Oxidants / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D053719:Tandem Mass Spectrometry; D014466:Ultraviolet Rays; D014865:Waste Disposal, Fluid / Q000379:methods; D062065:Wastewater / Q000032:analysis / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000528:radiation effects*
chemical_list: D006861:Hydrogen Peroxide; D016877:Oxidants; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Contaminant; Fluorescence; Indicator; Mass spectrometry; Reuse; Surrogates