title: On the bioavailability of trace metals in surface sediments: a combined geochemical and biological approach.
abstract: The bioavailability of metals was estimated in three river sediments (Sensée, Scarpe, and Deûle Rivers) impacted by different levels of Cu, Cd, Pb, and Zn (Northern France). For that, a combination of geochemistry and biological responses (bacteria and chironomids) was used. The results obtained illustrate the complexity of the notion of "bioavailability." Indeed, geochemical indexes suggested a low toxicity, even in surface sediments with high concentrations of total metals and a predicted severe effect levels for the organisms. This was also suggested by the abundance of total bacteria as determined by DAPI counts, with high bacterial cell numbers even in contaminated areas. However, a fraction of metals may be bioavailable as it was shown for chironomid larvae which were able to accumulate an important quantity of metals in surface sediments within just a few days.We concluded that (1) the best approach to estimate bioavailability in the selected sediments is a combination of geochemical and biological approaches and that (2) the sediments in the Deûle and Scarpe Rivers are highly contaminated and may impact bacterial populations but also benthic invertebrates.
authors.affiliation: Unité biotechnologie, Materia Nova, Rue des foudriers 1, 7822, Ghislenghien, Belgium. stephanie.roosa@materianova.be.|Proteomics and Microbiology Lab, Research Institute for Biosciences, Mons University, 20 Place du Parc, 7000, Mons, Belgium. stephanie.roosa@materianova.be.
authors.forename: Stéphanie
authors.identifier: http://orcid.org/0000-0002-5131-3520
authors.initials: S
authors.lastname: Roosa
authors.affiliation: Laboratory LASIR (UMR 8516 CNRS-Université Lille 1), 9655, Villeneuve d'Ascq, France.
authors.forename: Emilie
authors.initials: E
authors.lastname: Prygiel
authors.affiliation: Laboratory LASIR (UMR 8516 CNRS-Université Lille 1), 9655, Villeneuve d'Ascq, France.
authors.forename: Ludovic
authors.initials: L
authors.lastname: Lesven
authors.affiliation: Proteomics and Microbiology Lab, Research Institute for Biosciences, Mons University, 20 Place du Parc, 7000, Mons, Belgium.
authors.forename: Ruddy
authors.initials: R
authors.lastname: Wattiez
authors.affiliation: Proteomics and Microbiology Lab, Research Institute for Biosciences, Mons University, 20 Place du Parc, 7000, Mons, Belgium.
authors.forename: David
authors.initials: D
authors.lastname: Gillan
authors.affiliation: Centre Ecotox Eawag/EPFL, EPFL-ENAC-IIE-GE, Station 2, 1015, Lausanne, Switzerland.
authors.forename: Benoît J D
authors.initials: BJD
authors.lastname: Ferrari
authors.affiliation: Laboratory LASIR (UMR 8516 CNRS-Université Lille 1), 9655, Villeneuve d'Ascq, France.
authors.forename: Justine
authors.initials: J
authors.lastname: Criquet
authors.affiliation: Laboratory LASIR (UMR 8516 CNRS-Université Lille 1), 9655, Villeneuve d'Ascq, France.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Billon
mesh_terms: D000818:Animals; D001419:Bacteria / Q000302:isolation & purification; D001682:Biological Availability; D002683:Chironomidae / Q000378:metabolism*; D004784:Environmental Monitoring / Q000379:methods; D005602:France; D019015:Geologic Sediments / Q000032:analysis; D007814:Larva / Q000378:metabolism; D019216:Metals, Heavy / Q000032:analysis* / Q000378:metabolism*; D045483:Rivers / Q000737:chemistry / Q000382:microbiology; D014871:Water Microbiology; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000378:metabolism*
chemical_list: D019216:Metals, Heavy; D014874:Water Pollutants, Chemical
keywords: Bacterial community; Bioaccumulation; Chironomid; Metals; Toxicity index