title: Monitoring the Behavior of Emerging Contaminants in Wastewater-Impacted Rivers Based on the Use of Fluorescence Excitation Emission Matrixes (EEM).
abstract: This study investigated the applicability of fluorescence indexes based on the interpretation of excitation emission matrices (EEMs) by PARAFAC analysis and by selecting fluorescence intensities at a priori defined excitation/emission pairs as surrogates for monitoring the behavior of emerging organic compounds (EOCs) in two catchment basins impacted by wastewater discharges. Relevant EOC and EEM data were obtained for a 90 km stretch of the Simeto River, the main river in Sicily, and the smaller San Leonardo River, which was investigated for a 17 km stretch. The use of fluorescence indexes developed by these two different approaches resulted in similar observations. Changes of the fluorescence indexes that correspond to a group of humic-like fluorescing species were determined to be highly correlated with the concentrations of recalcitrant contaminants such as sucralose, sulfamethoxazole and carbamazepine, which are typical wastewater markers in river water. Changes of the fluorescence indexes related to tyrosine-like substances were well correlated with the concentrations of ibuprofen and caffeine, anthropogenic indicators of untreated wastewater discharges. Chemical oxygen demand and dissolved organic carbon concentrations were correlated with humic-like fluorescence indexes. The observed correlations were site-specific and characterized by different regression parameters for every collection event. Caffeine and carbamazepine showed correlations with florescence indexes in the San Leonardo River and in the alluvial plain stretch of the Simeto River, whereas sucralose, sulfamethoxazole and ibuprofen have always been well correlated in all the investigated river stretches. However, when data of different collection events from river stretches where correlations were observed were combined, good linear correlations were obtained for data sets generated via the normalization of the measured concentrations by the average value for the corresponding collection event. These results show that fluorescence based indexes can be used to monitor the behavior of some trace organic contaminants in wastewater impacted rivers and to track wastewater discharges in streams and rivers.
authors.affiliation: Department of Civil Engineering and Architecture, University of Catania , Viale A. Doria 6, 95125, Catania, Italy.
authors.forename: Massimiliano
authors.identifier: 0000-0002-3460-2814
authors.initials: M
authors.lastname: Sgroi
authors.affiliation: Department of Civil Engineering and Architecture, University of Catania , Viale A. Doria 6, 95125, Catania, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Roccaro
authors.affiliation: Department Civil and Environmental Engineering, University of Washington , Box 352700, Seattle, Washington 98195-2700, United States.
authors.forename: Gregory V
authors.identifier: 0000-0002-9226-6601
authors.initials: GV
authors.lastname: Korshin
authors.affiliation: Department of Civil Engineering and Architecture, University of Catania , Viale A. Doria 6, 95125, Catania, Italy.
authors.forename: Federico G A
authors.initials: FGA
authors.lastname: Vagliasindi
mesh_terms: D057919:Biological Oxygen Demand Analysis; D004784:Environmental Monitoring; D009930:Organic Chemicals / Q000737:chemistry; D045483:Rivers / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D062065:Wastewater
chemical_list: D009930:Organic Chemicals; D062065:Wastewater