title: Influence of reducing conditions on metallic elements released from various contaminated soil samples.
abstract: The redox conditions of soil may have significant consequences for the mobility of metallic elements (ME), but unlike pH, very few studies have investigated this parameter. A procedure was established to study the solubilization of ME from soil samples in various reducing conditions using a batch method and sodium ascorbate solutions. The change in redox potential from +410 to +10 mV was studied from four contaminated soil samples (designated A-D) of different origins and compositions. The results showed that ME mobilization greatly increased with decreasing redox potential within a limited and very sensitive range. Depending on the soil sample studied, various sensitive ranges of potentials were obtained (A, 220-345 mV; B, 280-365 mV; C, 260-360 mV; and D, 240-380 mV), and the induced percentages of ME mobilization varied (i.e., maximal values for Zn: A, 45%; B, 59%; C, 53%; and D, 58%). The results could be explained by the combined effect of potential and pH decrease on ME-carrying phases; in particular, Fe and Mn (oxy)hydroxides.
authors.affiliation: Université de Limoges, Groupement de Recherche Eau-Sol-Environnement, Faculté des Sciences & Techniques, Limoges, France.
authors.forename: Priscilla
authors.initials: P
authors.lastname: Pareuil
authors.forename: Sonia
authors.initials: S
authors.lastname: Pénilla
authors.forename: Nursen
authors.initials: N
authors.lastname: Ozkan
authors.forename: François
authors.initials: F
authors.lastname: Bordas
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Bollinger
mesh_terms: D005591:Chemical Fractionation; D004602:Elements; D008670:Metals / Q000737:chemistry*; D010084:Oxidation-Reduction; D019163:Reducing Agents / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis*; D012995:Solubility; D013997:Time Factors
chemical_list: D004602:Elements; D008670:Metals; D019163:Reducing Agents; D012989:Soil Pollutants