Authors: Laetitia Hédouin Marc Metian JeanLouis Teyssié Renaud Fichez Michel Warnau
Publish Date: 2017/03/09
Volume: 25, Issue: 12, Pages: 11206-11218
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 and 65Zn 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 halflives always 2 months The estimated transfer factor TF in clam tissues after a 35day sediment exposure was 1 to 4 orders of magnitude lower than the estimated CF indicating a lower bioavailability of sedimentbound 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 timeintegrated information about ambient contamination levels in the tropical marine coastal environmentThis work was supported by the International Atomic Energy Agency IAEA The support of French Ecosphère Continentale et Côtière—Programme National Environnement Côtier EC2COPNEC and the Institut de Recherche pour le Développement IRD is also acknowledged The IAEA is grateful for the support provided to its Environment Laboratories by the Government of the Principality of Monaco LH was beneficiary of a PhD grant CIFRE France supported by the Goro Nickel Company New Caledonia MW is an Honorary Senior Research Associate of the National Fund for Scientific Research NFSR Belgium
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