title: Delineation of Pb contamination pathways in two Pectinidae: the variegated scallop Chlamys varia and the king scallop Pecten maximus.
abstract: Bioaccumulation of Pb was determined in Chlamys varia and Pecten maximus exposed to (210)Pb via seawater, food and sediment. Both scallops readily concentrated dissolved Pb with whole-body 7-d concentration factors of 250+/-40 and 170+/-70, respectively. In both species, more than 70% of Pb taken up from seawater was strongly retained within tissues (biological half-life>1.5 month) whereas Pb ingested with phytoplankton was poorly assimilated (<20%). As P. maximus lives buried in the sediment, this exposure pathway was assessed and showed low bioaccumulation efficiency for sediment-bound Pb (transfer factor <0.015). Despite the poor transfer efficiency of Pb from food and sediment, the use of a global bioaccumulation model indicated that the particulate pathway (food and/or sediment) constituted the major bioaccumulation route of Pb in both scallops. Whatever the exposure pathway, the digestive gland and kidneys always played a major role in Pb accumulation. In scallop tissues, Pb was predominantly associated with the insoluble subcellular fraction, suggesting a low bioavailability of Pb for scallop consumers.
authors.affiliation: International Atomic Energy Agency - Marine Environment Laboratories, 4 Quai Antoine Ier, MC-98000, Principality of Monaco. metian@hawaii.com
authors.forename: Marc
authors.initials: M
authors.lastname: Metian
authors.forename: Michel
authors.initials: M
authors.lastname: Warnau
authors.forename: François
authors.initials: F
authors.lastname: Oberhänsli
authors.forename: Paco
authors.initials: P
authors.lastname: Bustamante
mesh_terms: D000818:Animals; D004064:Digestive System / Q000378:metabolism; D019015:Geologic Sediments / Q000737:chemistry; D006207:Half-Life; D007668:Kidney / Q000378:metabolism; D007854:Lead / Q000378:metabolism*; D007856:Lead Radioisotopes; D049897:Pectinidae / Q000378:metabolism*; D010839:Phytoplankton / Q000737:chemistry; D012623:Seawater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D007856:Lead Radioisotopes; D014874:Water Pollutants, Chemical; D007854:Lead