HR: 1340h
AN: B13C-1383    [Abstracts]
TI: Role of bacteria on the long term behaviour of waste confinement matrixes
AU: * Crovisier, J
EM: jlc@illite.u-strasbg.fr
AF: Ecole et Observatoire des Sciences de la Terre, Centre de Géochimie de la Surface UMR 7517, 1, rue Blessig, Strasbourg, 67000, France
AU: Bachelet, M
EM: mickael.bachelet@illite.u-strasbg.fr
AF: Ecole et Observatoire des Sciences de la Terre, Centre de Géochimie de la Surface UMR 7517, 1, rue Blessig, Strasbourg, 67000, France
AU: Geoffroy, V
EM: geoffroy@gem.u-strasbg.fr
AF: bLaboratoire de Génétique Moléculaire, Génomique, Microbiologie, Université Louis Pasteur, UMR 7156, 28, rue Goethe, Strasboug, 67000, France
AB: Bacteria are often presented as source of problems because they are suspected to accelerate the alteration of materials. Numerous works are based on patterns of holes and channels attributed to bacterial activity while no laboratory experiments clearly support these conclusions. A review of this important question will be presented. If microorganisms like Acidi Thiobacillus thiooxydans is able to metabolize strong acid by sulphur oxidation and contribute to accelerate the degradation of rocks and minerals, others one like Pseudomonas aeruginosa may produce protective exopolysaccharides (EPSs). These EPS may protect materials and also trap potentially toxic elements. To model the long term behaviour of waste confinme,nt matrixes, the effect of bacteria cannot be describe only on the basis of morphological patterns. One have to measure real rate which is only possible with specific growth media permitting to analyze weak concentration variations by ICP-MS (tracers)
DE: 0419 Biomineralization
SC: Biogeosciences [B]
MN: 2007 Fall Meeting