title: Experimental increase in availability of a PAH complex organic contamination from an aged contaminated soil: consequences on biodegradation.
abstract: Although high PAH content and detection of PAH-degraders, the PAH biodegradation is limited in aged-contaminated soils due to low PAH availability (i.e., 1%). Here, we tried to experimentally increase the soil PAH availability by keeping both soil properties and contamination composition. Organic extract was first removed and then re-incorporated in the raw soil as fresh contaminants. Though drastic, this procedure only allowed a 6-time increase in the PAH availability suggesting that the organic constituents more than ageing were responsible for low availability. In the re-contaminated soil, the mineralization rate was twice more important, the proportion of 5-6 cycles PAH was higher indicating a preferential degradation of lower molecular weight PAH. The extraction treatment induced bacterial and fungal community structures modifications, Pseudomonas and Fusarium solani species were favoured, and the relative quantity of fungi increased. In re-contaminated soil the percentage of PAH-dioxygenase gene increased, with 10 times more Gram negative representatives.
authors.affiliation: Université de Lorraine, Faculté des sciences, bd des Aiguillettes, 54506 Vandoeuvre-lès-Nancy, France. aurelie.cebron@univ-lorraine.fr
authors.forename: Aurélie
authors.initials: A
authors.lastname: Cébron
authors.forename: Pierre
authors.initials: P
authors.lastname: Faure
authors.forename: Catherine
authors.initials: C
authors.lastname: Lorgeoux
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Ouvrard
authors.forename: Corinne
authors.initials: C
authors.lastname: Leyval
mesh_terms: D001419:Bacteria / Q000187:drug effects / Q000254:growth & development; D001673:Biodegradation, Environmental / Q000187:drug effects; D005658:Fungi / Q000187:drug effects / Q000254:growth & development; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis / Q000633:toxicity*; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis / Q000633:toxicity*
chemical_list: D011084:Polycyclic Aromatic Hydrocarbons; D012987:Soil; D012989:Soil Pollutants