Journal article
Investigating fluorescent organic matter composition as a key predictor for arsenic mobility in groundwater aquifers
Environmental Fate & Effect of Chemicals, Department of Environmental Engineering, Technical University of Denmark1
Water Resources Engineering, Department of Environmental Engineering, Technical University of Denmark2
Department of Environmental Engineering, Technical University of Denmark3
National Institute of Aquatic Resources, Technical University of Denmark4
Section for Oceans and Arctic, National Institute of Aquatic Resources, Technical University of Denmark5
Kansas State University6
University of Copenhagen7
Dissolved organic matter (DOM) is linked to the heterogeneous distribution of elevated arsenic (As) in groundwater used for drinking and irrigation purposes, but the relationship between DOM characteristics and arsenic mobility has yet to be fully understood. Here, DOM from groundwater sampled in the Bengal Basin region was characterized using both conventional bulk emission-excitation (EEM) spectroscopy and high-performance size exclusion chromatography coupled to spectroscopy (HPSEC-EEM).
Notably, application of the novel HPSEC-EEM approach permitted the total fluorescence of individual samples to be independently resolved into its underlying components. This allowed the external validation of the bulk-sample fluorescence decomposition and offered insight into the molecular size distribution of fluorescent DOM.
Molecular size distributions were similar for the UVA fluorescent (C310, C340) as well as the three visible fluorescent (C390, C440 C500) components. There was a greater visible fluorescence in shallow aquifer samples (10-33 m) with high As (SH, up to 418µg/L) than in samples from the same depth with lower As (up to 40µg/L).
This indicated a link between DOM quality and As mobility within the shallow aquifer. The deep aquifer samples (170-200 m) revealed DOM characteristics similar to SH samples but had low As concentrations (
Language: | English |
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Publisher: | American Chemical Society |
Year: | 2018 |
Pages: | 13027-13036 |
ISSN: | 15205851 and 0013936x |
Types: | Journal article |
DOI: | 10.1021/acs.est.8b04070 |
ORCIDs: | 0000-0001-8123-6274 , Wünsch, Urban , 0000-0001-6164-3163 , McKnight, Ursula S. , Battistel, Maria and Stedmon, Colin |
Arsenic Dissolved organis matter (DOM) EEM fluorescence spectroscopy Groundwater resoruces HPSEC-EEM-PARAFAC
Coloring Agents Drinking Water Groundwater Water Pollutants, Chemical