title: Specific pathways for the incorporation of dissolved barium and molybdenum into the bivalve shell: an isotopic tracer approach in the juvenile Great Scallop (Pecten maximus).
abstract: Dissolved barium and molybdenum incorporation in the calcite shell was investigated in the Great Scallop Pecten maximus. Sixty six individuals were exposed for 16 days to two successive dissolved Ba and Mo concentrations accurately differentiated by two different isotopic enrichments (⁹⁷Mo, ⁹⁵Mo; ¹³⁵Ba, ¹³⁷Ba). Soft tissue and shell isotopic composition were determined respectively by quantitative ICP-MS (Inductively Coupled Plasma Mass Spectrometer) and laser ablation--ICP-MS. Results from Ba enrichment indicate the direct incorporation of dissolved Ba into the shell in proportion to the levels in the water in which they grew with a 6-8 day delay. The low spike contributions and the low partition coefficient (D(Mo) = 0.0049 ± 0.0013), show that neither the soft tissue nor the shell were significantly sensitive to Mo enrichment. These results eliminate direct Mo shell enrichment by the dissolved phase, and favour a trophic uptake that will be investigated using the successive isotopic enrichment approach developed in this study.
authors.affiliation: Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, Institut des Sciences Analytiques et de Physico-Chimie pour l'Environnement et les Matériaux, UMR 5254 CNRS-Université de Pau et des Pays de l'Adour, Pau, France. tabouret@mnhn.fr
authors.forename: Hélène
authors.initials: H
authors.lastname: Tabouret
authors.forename: Sébastien
authors.initials: S
authors.lastname: Pomerleau
authors.forename: Aurélie
authors.initials: A
authors.lastname: Jolivet
authors.forename: Christophe
authors.initials: C
authors.lastname: Pécheyran
authors.forename: Ricardo
authors.initials: R
authors.lastname: Riso
authors.forename: Julien
authors.initials: J
authors.lastname: Thébault
authors.forename: Laurent
authors.initials: L
authors.lastname: Chauvaud
authors.forename: David
authors.initials: D
authors.lastname: Amouroux
mesh_terms: D000818:Animals; D001464:Barium / Q000032:analysis / Q000378:metabolism* / Q000494:pharmacology; D005880:Gills / Q000378:metabolism; D007554:Isotopes; D008982:Molybdenum / Q000032:analysis / Q000378:metabolism* / Q000494:pharmacology; D009132:Muscles / Q000378:metabolism; D049897:Pectinidae / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D012623:Seawater / Q000032:analysis
chemical_list: D007554:Isotopes; D001464:Barium; D008982:Molybdenum