Concentrations and Distributions of Metals Associated with Dissolved Organic Matter from the Suwannee River (GA, USA)

Author(s)
Keshia M. Kuhn, Elisabeth Neubauer, Thilo Hofmann, Frank von der Kammer, George R. Aiken, Patricia A. Maurice
Abstract

Concentrations and distributions of metals in Suwannee River (SR) raw filtered surface water (RFSW) and dissolved organic matter (DOM) processed by reverse osmosis (RO), XAD-8 resin (for humic and fulvic acids [FA]), and XAD-4 resin (for "transphilic" acids) were analyzed by asymmetrical flow field-flow fractionation (AsFlFFF). SR samples were compared with DOM samples from Nelson's Creek (NLC), a wetland-draining stream in northern Michigan; previous International Humic Substances Society (IHSS) FA and RO samples from the SR; and an XAD-8 sample from Lake Fryxell (LF), Antarctica. Despite application of cation exchange during sample processing, all XAD and RO samples contained substantial metal concentrations. AsFlFFF fractograms allowed metal distributions to be characterized as a function of DOM component molecular weight (MW). In SR RFSW, Fe, Al, and Cu were primarily associated with intermediate to higher than average MW DOM components. SR RO, XAD-8, and XAD-4 samples from May 2012 showed similar MW trends for Fe and Al but Cu tended to associate more with lower MW DOM. LF DOM had abundant Cu and Zn, perhaps due to amine groups that should be present due to its primarily algal origins. None of the fractograms showed obvious evidence for mineral nanoparticles, although some very small mineral nanoparticles might have been present at trace concentrations. This research suggests that AsFlFFF is important for understanding how metals are distributed in different DOM samples (including IHSS samples), which may be key to metal reactivity and bioavailability.

Organisation(s)
External organisation(s)
University of Notre Dame, United States Geological Survey
Journal
Environmental Engineering Science
Volume
32
Pages
54-65
No. of pages
12
ISSN
1092-8758
DOI
https://doi.org/10.1089/ees.2014.0298
Publication date
01-2015
Peer reviewed
Yes
Austrian Fields of Science 2012
105302 Hydrochemistry, 105303 Hydrogeology, 104002 Analytical chemistry, 105904 Environmental research
Keywords
ASJC Scopus subject areas
Pollution, Waste Management and Disposal, Environmental Chemistry
Portal url
https://ucrisportal.univie.ac.at/en/publications/concentrations-and-distributions-of-metals-associated-with-dissolved-organic-matter-from-the-suwannee-river-ga-usa(87036c55-217d-49da-8697-0349cf9cac33).html