title: Arsenic Mobilization from Historically Contaminated Mining Soils in a Continuously Operated Bioreactor: Implications for Risk Assessment.
abstract: Concentrations of soil arsenic (As) in the vicinity of the former Złoty Stok gold mine (Lower Silesia, southwest Poland) exceed 1000 μg g(-1) in the area, posing an inherent threat to neighboring bodies of water. This study investigated continuous As mobilization under reducing conditions for more than 3 months. In particular, the capacity of autochthonic microflora that live on natural organic matter as the sole carbon/electron source for mobilizing As was assessed. A biphasic mobilization of As was observed. In the first two months, As mobilization was mainly conferred by Mn dissolution despite the prevalence of Fe (0.1 wt % vs 5.4 for Mn and Fe, respectively) as indicated by multiple regression analysis. Thereafter, the sudden increase in aqueous As[III] (up to 2400 μg L(-1)) was attributed to an almost quintupling of the autochthonic dissimilatory As-reducing community (quantitative polymerase chain reaction). The aqueous speciation influenced by microbial activity led to a reduction of solid phase As species (X-ray absorption fine structure spectroscopy) and a change in the elemental composition of As hotspots (micro X-ray fluorescence mapping). The depletion of most natural dissolved organic matter and the fact that an extensive mobilization of As[III] occurred after two months raises concerns about the long-term stability of historically As-contaminated sites.
authors.affiliation: Institute for Ecopreneurship, School of Life Sciences, University of Applied Sciences and Arts Northwestern Switzerland , Gründenstrasse 40, 4132 Muttenz, Switzerland.
authors.forename: Liwia
authors.initials: L
authors.lastname: Rajpert
authors.affiliation: Institute for Ecopreneurship, School of Life Sciences, University of Applied Sciences and Arts Northwestern Switzerland , Gründenstrasse 40, 4132 Muttenz, Switzerland.
authors.forename: Boris A
authors.initials: BA
authors.lastname: Kolvenbach
authors.affiliation: Institute for Ecopreneurship, School of Life Sciences, University of Applied Sciences and Arts Northwestern Switzerland , Gründenstrasse 40, 4132 Muttenz, Switzerland.
authors.forename: Erik M
authors.initials: EM
authors.lastname: Ammann
authors.affiliation: Institute of Terrestrial Ecosystems, Department of Environmental Systems Science, ETH Zürich , Universitätstrasse 16, 8092 Zürich, Switzerland.
authors.forename: Kerstin
authors.initials: K
authors.lastname: Hockmann
authors.affiliation: Paul Scherrer Institute, 5232 Villigen - PSI Switzerland.
authors.forename: Maarten
authors.initials: M
authors.lastname: Nachtegaal
authors.affiliation: Institute of Applied Geosciences, Karlsruhe Institute of Technology (KIT) , Adenauerring 20b, 76131 Karlsruhe, Germany.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Eiche
authors.affiliation: Institute for Environmental Research (Biology V), RWTH Aachen University , 52074 Aachen, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Schäffer
authors.affiliation: Institute for Ecopreneurship, School of Life Sciences, University of Applied Sciences and Arts Northwestern Switzerland , Gründenstrasse 40, 4132 Muttenz, Switzerland.
authors.forename: Philippe Francois Xavier
authors.initials: PF
authors.lastname: Corvini
authors.affiliation: Laboratory of Environmental Pollution Analysis, University of Warsaw , 02-096 Warsaw, Poland.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Skłodowska
authors.affiliation: Institute for Ecopreneurship, School of Life Sciences, University of Applied Sciences and Arts Northwestern Switzerland , Gründenstrasse 40, 4132 Muttenz, Switzerland.|Sub-Department of Environmental Technology, Wageningen University , 6700 EV Wageningen, The Netherlands.
authors.forename: Markus
authors.initials: M
authors.lastname: Lenz
mesh_terms: D001151:Arsenic; D019149:Bioreactors; D008906:Mining; D018570:Risk Assessment; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants
chemical_list: D012987:Soil; D012989:Soil Pollutants; D001151:Arsenic