title: Thallium contamination of soils/vegetation as affected by sphalerite weathering: a model rhizospheric experiment.
abstract: The environmental stability of Tl-rich sphalerite in two contrasting soils was studied. Rhizospheric conditions were simulated to assess the risk associated with sulfide microparticles entering agricultural (top)soils. The data presented here clearly demonstrate a significant effect of 500 μM citric acid, a model rhizospheric solution, on ZnS alteration followed by enhanced Tl and Zn release. The relative ZnS mass loss after 28 days of citrate incubation reached 0.05 and 0.03 wt.% in Cambisol and Leptosol samples respectively, and was up to 4 times higher, compared to H2O treatments. Incongruent (i.e., substantially increased) mobilization of Tl from ZnS was observed during the incubation time. Generally higher (long-term) stability of ZnS with lower Tl release is predicted for soils enriched in carbonates. Furthermore, the important role of silicates (mainly illite) in the stabilization of mobilized Tl, linked with structural (inter)layer Tl-K exchange, is suggested. Thallium was highly bioavailable, as indicated by its uptake by white mustard; maximum Tl amounts were detected in biomass grown on the acidic Cambisol. Despite the fact that sulfides are thought as relatively stable phases in soil environments, enhanced sulfide dissolution and Tl/trace element release (and bioaccumulation) can be assumed in rhizosphere systems.
authors.affiliation: Department of Soil Science and Soil Protection, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamýcká 129, 165 21 Praha 6, Czech Republic. Electronic address: vaneka@af.czu.cz.
authors.forename: Aleš
authors.initials: A
authors.lastname: Vaněk
authors.affiliation: Department of Soil Science and Soil Protection, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamýcká 129, 165 21 Praha 6, Czech Republic.
authors.forename: Zuzana
authors.initials: Z
authors.lastname: Grösslová
authors.affiliation: Institute of Geochemistry, Mineralogy and Mineral Resources, Faculty of Science, Charles University in Prague, Albertov 6, 128 43 Praha 2, Czech Republic.
authors.forename: Martin
authors.initials: M
authors.lastname: Mihaljevič
authors.affiliation: Institute of Geochemistry, Mineralogy and Mineral Resources, Faculty of Science, Charles University in Prague, Albertov 6, 128 43 Praha 2, Czech Republic.
authors.forename: Vojtěch
authors.initials: V
authors.lastname: Ettler
authors.affiliation: Department of Environmental Geosciences, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 165 21 Praha 6, Czech Republic.
authors.forename: Vladislav
authors.initials: V
authors.lastname: Chrastný
authors.affiliation: Department of Environmental Geosciences, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 165 21 Praha 6, Czech Republic.
authors.forename: Michael
authors.initials: M
authors.lastname: Komárek
authors.affiliation: Department of Soil Science and Soil Protection, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamýcká 129, 165 21 Praha 6, Czech Republic.
authors.forename: Václav
authors.initials: V
authors.lastname: Tejnecký
authors.affiliation: Department of Soil Science and Soil Protection, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamýcká 129, 165 21 Praha 6, Czech Republic.
authors.forename: Ondřej
authors.initials: O
authors.lastname: Drábek
authors.affiliation: Department of Soil Science and Soil Protection, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamýcká 129, 165 21 Praha 6, Czech Republic.
authors.forename: Vít
authors.initials: V
authors.lastname: Penížek
authors.affiliation: Department of Soil Science and Soil Protection, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamýcká 129, 165 21 Praha 6, Czech Republic.
authors.forename: Ivana
authors.initials: I
authors.lastname: Galušková
authors.affiliation: Department of Soil Science and Soil Protection, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamýcká 129, 165 21 Praha 6, Czech Republic.
authors.forename: Barbora
authors.initials: B
authors.lastname: Vaněčková
authors.affiliation: Department of Soil Science and Soil Protection, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamýcká 129, 165 21 Praha 6, Czech Republic.
authors.forename: Lenka
authors.initials: L
authors.lastname: Pavlů
authors.affiliation: Department of Soil Science and Soil Protection, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamýcká 129, 165 21 Praha 6, Czech Republic.
authors.forename: Christopher
authors.initials: C
authors.lastname: Ash
mesh_terms: D004784:Environmental Monitoring; D008903:Minerals / Q000737:chemistry; D008956:Models, Chemical; D058441:Rhizosphere; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis* / Q000737:chemistry; D013793:Thallium / Q000032:analysis* / Q000737:chemistry
chemical_list: D008903:Minerals; D012987:Soil; D012989:Soil Pollutants; D013793:Thallium
keywords: Dissolution; Release; Rhizosphere; Trace element