title: Solubilization of Pb-bearing apatite Pb5(PO4)3Cl by bacteria isolated from polluted environment.
abstract: The main purpose of this study was to test if microorganisms isolated from heavily polluted environments can enhance dissolution of Pb-apatite (pyromorphite) resulting in remobilization of lead. Three bacterial strains belonging to the genus Pseudomonas isolated from underground mines in SW Poland were used in batch experiments of pyromorphite solubilization carried out in phosphate reach and phosphate poor media. Bacteria growth and evolution of Pb and phosphate concentrations as well as pH were determined. Additionally the concentration of bacterial siderophores in leaching solution was assayed. All bacterial strains were able to grow in both media in the presence of pyromorphite. The number of bacterial cells was from one to two orders of magnitude higher in the phosphate rich media. In the phosphate poor media the only source of P was the dissolving lead apatite. Bacteria enhanced the solubility of pyromorphite resulting in elevated Pb concentrations, up to 853 μg L-1in phosphate-rich medium and 6112 μg L-1in phosphate-poor medium, compared to less than 100 μg L-1in an abiotic control sample. Production of siderophores was characteristic for each culture and was much lower (10-1000 fold) in the phosphate-poor medium. This study demonstrates for the first time that indigenous bacteria can directly and indirectly promote the mobilization of lead from pyromorphite. This phenomenon should be considered in long term risk assessment of Pb contaminated soils after reclamation processes because bacteria can play a significant role in the efficiency of clean-up efforts and overall geochemical cycling of Pb.
authors.affiliation: Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland.
authors.forename: Łukasz
authors.initials: Ł
authors.lastname: Drewniak
authors.affiliation: Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Skłodowska
authors.affiliation: Faculty of Geology, Geophysics and Environmental Protection, AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Krakow, Poland.
authors.forename: Maciej
authors.initials: M
authors.lastname: Manecki
authors.affiliation: Faculty of Geology, Geophysics and Environmental Protection, AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Krakow, Poland. Electronic address: bajda@agh.edu.pl.
authors.forename: Tomasz
authors.initials: T
authors.lastname: Bajda
mesh_terms: D001031:Apatites / Q000032:analysis / Q000378:metabolism*; D001419:Bacteria / Q000378:metabolism*; D001673:Biodegradation, Environmental; D004787:Environmental Pollution; D007854:Lead / Q000032:analysis / Q000378:metabolism*; D008903:Minerals / Q000032:analysis / Q000378:metabolism*; D010710:Phosphates / Q000032:analysis / Q000378:metabolism*; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism*
chemical_list: D001031:Apatites; D008903:Minerals; D010710:Phosphates; D012989:Soil Pollutants; C471364:pyromorphite; D007854:Lead
keywords: Biosolubilization; Lead; Pseudomonas sp.; Pyromorphite; Siderophores