title: Investigation of the release of PAHs from artificially contaminated sediments using cyclolipopeptidic biosurfactants.
abstract: Polycyclic aromatic hydrocarbons (PAHs) can be preponderant in contaminated sediments and understanding how they are sorbed in the different mineral and organic fractions of the sediment is critical for effective removal strategies. For this purpose, a mixture of seven PAHs was studied at the sediment/water interface and sorption isotherms were obtained. The influence of various factors on the sorption behavior of PAHs was evaluated, such as the nature of minerals, pH, ionic strength and amount of organic matter. Afterwards, the release of PAHs from the sediment by surfactants was investigated. The effectiveness of sodium dodecyl sulfate (SDS) was compared to natural biosurfactants, of cyclolipopeptidic type (amphisin and viscosin-like mixture), produced by two Pseudomonas fluorescens strains. The desorption of PAHs (from naphthalene to pyrene), from the highly retentive kaolinite fraction, could be favored by adding SDS or amphisin, but viscosin-like biosurfactants were only effective for 2-3 ring PAHs desorption (naphthalene to phenanthrene). Moreover, while SDS favors the release of all the target PAHs from a model sediment containing organic matter, the two biosurfactants tested were only effective to desorb the lowest molecular weight PAHs (naphthalene to fluorene).
authors.affiliation: COBRA UMR CNRS 6014, Université de Rouen, 55 rue Saint Germain, 27000 Evreux, France. Electronic address: florence.koltalo@univ-rouen.fr.
authors.forename: F
authors.initials: F
authors.lastname: Portet-Koltalo
authors.forename: M T
authors.initials: MT
authors.lastname: Ammami
authors.forename: A
authors.initials: A
authors.lastname: Benamar
authors.forename: H
authors.initials: H
authors.lastname: Wang
authors.forename: F
authors.initials: F
authors.lastname: Le Derf
authors.forename: C
authors.initials: C
authors.lastname: Duclairoir-Poc
mesh_terms: D000327:Adsorption; D052918:Environmental Restoration and Remediation / Q000379:methods; D019015:Geologic Sediments / Q000737:chemistry; D055666:Lipopeptides / Q000737:chemistry* / Q000378:metabolism; D010456:Peptides, Cyclic / Q000737:chemistry* / Q000378:metabolism; D011084:Polycyclic Aromatic Hydrocarbons / Q000737:chemistry*; D011551:Pseudomonas fluorescens / Q000378:metabolism; D013501:Surface-Active Agents / Q000737:chemistry* / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D055666:Lipopeptides; D010456:Peptides, Cyclic; D011084:Polycyclic Aromatic Hydrocarbons; D013501:Surface-Active Agents; D014874:Water Pollutants, Chemical
keywords: Biosurfactants; PAHs release; Polycyclic aromatic hydrocarbons; Sorption isotherms; Water/sediment interface