title: Shell disturbances and butyltins burden in commercial bivalves collected from the Bizerta lagoon (northern Tunisia).
abstract: Shell disturbances and soft tissues butyltin burden were investigated in commercial bivalves Lithophaga lithophaga, Mytilus galloprovincialis, Solen marginatus and Crassostrea gigas from the Bizerta lagoon. Shell disturbances were found in all bivalves, being scarce in S. marginatus. In the internal valve of L. lithophaga, burrowing annelids and sipunculids living inside galleries were observed, while in the external valve, brown-blackish or white stains were found. In M. galloprovincialis, a yellowish mass located at the shell anterior side was found fixed firmly to the pearly layer by a hard brownish structure covering some annelid elliptic eggs. In the internal shell layer of some specimens collected in April, embryos belonging to tubiculous annelids at various developmental stages were observed. In C. gigas, shell thickening was revealed in some specimens corresponding to white doughy deposits at the internal valve and between shell layers. In S. marginatus, only one specimen showing a cavity at the posterior site was found. Total butyltin concentrations in the studied bivalves varied between 30 and 245 ng/g dry weight with tributyltin (TBT) being the predominant compound. The highest concentration was recorded in L. lithophaga collected from the Bizerta Bay and the lowest concentration in S. marginatus from Maghraoua. This study provided baseline data that could serve for long-term monitoring of TBT pollution in Tunisia, since legislation to reduce the use of TBT-based antifouling paints has not been introduced yet.
authors.affiliation: Faculty of Sciences of Bizerta, Department of Life Sciences, Laboratory of Environment Bio-monitoring (LBE), University of Carthage, 7021 Zarzouna, Bizerta, Tunisia.
authors.forename: Ferdaous Jaafar
authors.initials: FJ
authors.lastname: Kefi
authors.forename: Youssef
authors.initials: Y
authors.lastname: Lahbib
authors.forename: Lamia Gargouri Ben
authors.initials: LG
authors.lastname: Abdallah
authors.forename: Najoua Trigui
authors.initials: NT
authors.lastname: El Menif
mesh_terms: D060105:Animal Shells / Q000033:anatomy & histology / Q000737:chemistry / Q000187:drug effects*; D000818:Animals; D049872:Bivalvia / Q000378:metabolism*; D004784:Environmental Monitoring; D012623:Seawater / Q000737:chemistry; D014220:Trialkyltin Compounds / Q000032:analysis / Q000378:metabolism* / Q000633:toxicity; D014416:Tunisia; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000378:metabolism* / Q000633:toxicity
chemical_list: D014220:Trialkyltin Compounds; D014874:Water Pollutants, Chemical; C011559:tributyltin