title: High contribution of the particulate uptake pathway to metal bioaccumulation in the tropical marine clam Gafrarium pectinatum.
abstract: The clam Gafrarium pectinatum was investigated to assess its usefulness as a bioindicator species of metal mining contamination in the New Caledonia lagoon. The uptake and depuration kinetics of Ag, Cd, Co, Cr, and Zn were determined following exposures via seawater, sediment, and food using highly sensitive radiotracer techniques (110mAg,109Cd,51Cr,57Co, and65Zn). When the clams were exposed to dissolved metals, Co, Zn, and Ag were readily incorporated in their tissues (concentration factors (CF) ranging from 181 to 4982 after 28 days of exposure) and all metals were strongly retained (biological half-lives always >2 months). The estimated transfer factor (TF) in clam tissues after a 35-day sediment exposure was 1 to 4 orders of magnitude lower than the estimated CF, indicating a lower bioavailability of sediment-bound metals than dissolved ones. Once incorporated, metals taken up from sediment and seawater were retained longer than metals ingested with food, indicating that the uptake pathway influences the storage processes of metals in clam tissues. Compilation of our data into a global bioaccumulation model indicated that, except for Ag that essentially originated from food (92%), sediment was the main source of metal bioaccumulation in the clam (more than 80%). These results highlight that bioaccumulation processes strongly depend from one metal to the other. The overall efficient bioaccumulation and retention capacities of the clam G. pectinatum confirm its usefulness as a bioindicator species that can provide time-integrated information about ambient contamination levels in the tropical marine coastal environment.
authors.affiliation: International Atomic Energy Agency-Environment Laboratories (IAEA-EL), 4a Quai Antoine Ier, MC-98000, Monaco, Principality of Monaco. laetitia.hedouin@criobe.pf.|Littoral Environnement et Sociétés (LIENSs), UMR 6250 CNRS, Université La Rochelle, 2 Rue Olympe de Gouges, 17042, La Rochelle Cedex 01, France. laetitia.hedouin@criobe.pf.|Mediterranean Institute of Oceanography (MIO), Aix-Marseille Université, CNRS/INSU, Université de Toulon, IRD, UM 110, 13288, Marseille, France. laetitia.hedouin@criobe.pf.|USR378 EPHE CNRS UPVD-CRIOBE, Laboratoire d'Excellence CORAIL, BP1013, 98729, Papetoai, Moorea, French Polynesia. laetitia.hedouin@criobe.pf.|PSL Research University: EPHE-UPVD-CNRS, USR 3278 CRIOBE, Laboratoire d'Excellence «CORAIL», PSL Research University, BP 1013, 98729, Papetoai, Moorea, French Polynesia. laetitia.hedouin@criobe.pf.
authors.forename: Laetitia
authors.initials: L
authors.lastname: Hédouin
authors.affiliation: International Atomic Energy Agency-Environment Laboratories (IAEA-EL), 4a Quai Antoine Ier, MC-98000, Monaco, Principality of Monaco.
authors.forename: Marc
authors.initials: M
authors.lastname: Metian
authors.affiliation: International Atomic Energy Agency-Environment Laboratories (IAEA-EL), 4a Quai Antoine Ier, MC-98000, Monaco, Principality of Monaco.
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Teyssié
authors.affiliation: Mediterranean Institute of Oceanography (MIO), Aix-Marseille Université, CNRS/INSU, Université de Toulon, IRD, UM 110, 13288, Marseille, France.
authors.forename: Renaud
authors.initials: R
authors.lastname: Fichez
authors.affiliation: International Atomic Energy Agency-Environment Laboratories (IAEA-EL), 4a Quai Antoine Ier, MC-98000, Monaco, Principality of Monaco.
authors.forename: Michel
authors.initials: M
authors.lastname: Warnau
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000378:metabolism; D019015:Geologic Sediments / Q000032:analysis* / Q000737:chemistry; D008670:Metals / Q000032:analysis* / Q000737:chemistry; D008906:Mining; D009510:New Caledonia; D017747:Seafood; D012623:Seawater; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry
chemical_list: D008670:Metals; D014874:Water Pollutants, Chemical
keywords: Bioaccumulation; Mining activities; Radiotracers; Seafood; Tropical