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Dietary exposure of juvenile common sole (Solea solea L.) to polybrominated diphenyl ethers (PBDEs): Part 1. Bioaccumulation and elimination kinetics of individual congeners and their debrominated metabolites
2011
Munschy, Catherine | Moisan, Karine | Tixier, Celine | Olivier, Nathalie | Gastineau, Olivier | Le Bayon, Nicolas | Buchet, Vincent
The uptake and elimination of six PBDE congeners (BDE-28, -47, -99, -100, -153, -209) were studied in juvenile common sole (Solea solea L) exposed to spiked contaminated food over a three-month period, then depurated over a five-month period. The results show that all of the studied PBDEs accumulate in fish tissues, including the higher brominated congener BDE-209. Several additional PBDE congeners were identified in the tissues of exposed fish, revealing PBDE transformation, mainly via debromination. The identified congeners originating from PBDE debromination include BDE-49 and BDE-202 and a series of unidentified tetra-, penta-, and hepta- BDEs. Contaminant assimilation efficiencies (AEs) were related to their hydrophobicity (log K-ow) and influenced by PBDE biotransformation. Metabolism via debromination appears to be a major degradation route of PBDEs in juvenile sole in comparison to biotransformation into hydroxylated metabolites. (C) 2010 Elsevier Ltd. All rights reserved.
Afficher plus [+] Moins [-]Atmospheric concentrations, occurrence and deposition of persistent organic pollutants (POPs) in a Mediterranean coastal site (Etang de Thau, France)
2011
Castro Jimenez, Javier | Mariani, G. | Vives, I. | Skejo, H. | Umlauf, G. | Zaldivar, J. M. | Dueri, Sibylle | Messiaen, Gregory | Laugier, Thierry
Atmospheric concentrations and deposition fluxes of PCDD/F and PCB have been evaluated over a 1-year period in a Mediterranean coastal lagoon (Etang de Thau, France). Indicative PBDE air concentrations in the hot season are also reported in this work. ∑2,3,7,8-PCDD/Fs and ∑18PCBs (gas + particulate) air concentrations ranged from 67 to 1700 fg m−3 and from 13 to 95 pg m−3, respectively whereas ∑8PBDEs (gas + particulate) summer time levels varied from 158 to 230 pg m−3. The PCDD/F and PCB atmospheric occurrence over Thau lagoon and subsequent inputs to the surface waters are determined by an assemble of factors, being the seasonality of atmospheric concentration, the air mass origin and meteorological conditions important drivers. Total (wet + dry) ∑2,3,7,8-PCDD/Fs and ∑18PCBs deposition fluxes to Thau Lagoon waters are 117 and 715 pg m−2 d−1, respectively.
Afficher plus [+] Moins [-]Bioavailability of particulate metal to zebra mussels: Biodynamic modelling shows that assimilation efficiencies are site-specific
2011
Bourgeault, Adeline | Gourlay-france, Catherine | Priadi, Cindy | Ayrault, Sophie | Tusseau-vuillemin, Marie-helene
This study investigates the ability of the biodynamic model to predict the trophic bioaccumulation of cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni) and zinc (Zn) in a freshwater bivalve. Zebra mussels were transplanted to three sites along the Seine River (France) and collected monthly for 11 months. Measurements of the metal body burdens in mussels were compared with the predictions from the biodynamic model. The exchangeable fraction of metal particles did not account for the bioavailability of particulate metals, since it did not capture the differences between sites. The assimilation efficiency (AE) parameter is necessary to take into account biotic factors influencing particulate metal bioavailability. The biodynamic model, applied with AEs from the literature, overestimated the measured concentrations in zebra mussels, the extent of overestimation being site-specific. Therefore, an original methodology was proposed for in situ AE measurements for each site and metal. (C) 2011 Elsevier Ltd. All rights reserved.
Afficher plus [+] Moins [-]Impact of atmospheric deposition of anthropogenic and natural trace metals on Northwestern Mediterranean surface waters: A box model assessment
2011
Heimbuerger, Lars-eric | Migon, Christophe | Cossa, Daniel
Under stratified oligotrophic conditions (May November), the surface mixed layer of the Northwestern Mediterranean constitutes a homogeneous water volume of 10-30 m depth. In other respects, the mean residence time of Ligurian surface waters (0-200 m) is 102 days. It is therefore possible to quantify the extent to which atmospheric deposition of trace metals affects surface waters. On the basis of literature data on anthropogenic and natural trace metals, we demonstrate that the ratios between total seawater labile atmospheric deposition during 102 days (Delta c) and dissolved TM concentrations in Ligurian surface waters (c) illustrate the impact of atmospheric deposition on surface seawater (Delta c/c). High ratios indicate surface TM enrichments, while low ratios indicate surface TM depletion, due to the quasi-complete sorption and removal of TMs by plankton during spring bloom. The simple box model proposed here may be used for other marine regions where hydrodynamical and physico-chemical constraints are well defined. (C) 2011 Elsevier Ltd. All rights reserved.
Afficher plus [+] Moins [-]Recommendations on methods for the detection and control of biological pollution in marine coastal waters
2011
Olenin, Sergej | Elliott, Michael | Bysveen, Ingrid | Culverhouse, Phil F. | Daunys, Darius | Dubelaar, George B. J. | Gollasch, Stephan | Goulletquer, Philippe | Jelmert, Anders | Kantor, Yuri | Mezeth, Kjersti Bringsvor | Minchin, Dan | Occhipinti-ambrogi, Anna | Olenina, Irina | Vandekerkhove, Jochen
Adverse effects of invasive alien species (IAS), or biological pollution, is an increasing problem in marine coastal waters, which remains high on the environmental management agenda. All maritime countries need to assess the size of this problem and consider effective mechanisms to prevent introductions, and if necessary and where possible to monitor, contain, control or eradicate the introduced impacting organisms. Despite this, and in contrast to more enclosed water bodies, the openness of marine systems indicates that once species are in an area then eradication is usually impossible. Most institutions in countries are aware of the problem and have sufficient governance in place for management. However, there is still a general lack of commitment and concerted action plans are needed to address this problem. This paper provides recommendations resulting from an international workshop based upon a large amount of experience relating to the assessment and control of biopollution. Highlights ► We summarize the results of an international workshop on marine biopollution. ► We recommend science-based information support for bioinvasion management. ► We outline types of bioinvasion monitoring and consider topical research needs. ► We emphasize the role of taxonomy training and public involvement. ► Biopollution should be treated in the same way as any other type of pollution.
Afficher plus [+] Moins [-]Relationship between valve activity, microalgae concentration in the water and toxin accumulation in the digestive gland of the Pacific oyster Crassostrea gigas exposed to Alexandrium minutum
2011
Haberkorn, Hansy | Tran, Damien | Massabuau, Jean-charles | Ciret, Pierre | Savar, Veronique | Soudant, Philippe
The complexity of the relationships between Alexandrium minutum (Am.) concentration in the water ([A.m.](w)), Paralytic Shellfish Poisoning contamination in the digestive gland ([PSP](dg)) and valve behavior was explored in oysters Crassostrea gigas. Two experiments were conducted, during which oysters' valve behaviour were analyzed. Oysters, first acclimated for 10-days with the non harmful microalgae Heterocapsa triquetra (H.t.), were exposed to four microalgae mixtures at constant total concentrations of 10 x 10(3) cells ml(-1) (experiment-1) and 5 x 10(3) cells ml(-1) (experiment-2): 100% Am.; 50% A.m.-50% H.t.; 25% A.m.-75% H.t.; 100% H.t. At the end of experiment-2, [PSP](dg) were measured. At 10 x 103 cells ml(-1), the microalgal ingestion decreased (p < 0.05) with increasing [A.m.](w) but not at 5 x 10(3) cells ml(-1) (p > 0.05). The frequency of microclosures specifically increased with [A.m.](w) (p < 0.05) and the opening duration with [PSP](dg) (p < 0.0001). Oysters exhibiting the maximum increase in opening duration also exhibited the highest [PSP](dg). The results are discussed in terms of oyster physiology and origin of the behavioral response. (C) 2011 Elsevier Ltd. All rights reserved.
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