Lead contamination of small cetaceans of the european coasts: the use of stable isotopes for identifiying the sources of lead exposure

1 page.-- Eighteenth Annual Conference of the European Cetacean Society, Kolmården, Sweden, 28-31 March 2004This work is part of the European project BIOCET which aims to quantify and model the effect of bioaccumulation of persistant organic pollutants in small cetaceans in European waters by taking into account confounding factors, in particular trace elements.N

Use of skin and blubber tissues of small cetaceans to assess the trace element content of internal organs

In order to evaluate the use of biopsy samples as non-destructive tool for assessing trace element concentrations in small cetaceans, the concentrations of 14 trace elements were determined in skin, blubber, liver and kidneys of four species of small cetaceans (i.e. common dolphin Delphinus delphis, harbour porpoise Phocoena phocoena, bottlenose dolphin Tursiops truncatus and striped dolphin Stenella coeruleolba), stranded and/or by-caught along the NE Atlantic Ocean coast between 2001 and 2008. Only Cu, Fe, Hg, Mn, Ni and Zn were above the detection limit of the instruments and showed recoveries satisfactory enough to be interpreted. Among these trace elements, Hg was the only one showing a significant correlation between concentrations in and those in liver and kidneys. In consequence skin and blubber can only be used as non-invasive monitoring tissues to investigate Hg bioaccumulation in internal tissues for cetacean populations.We greatly acknowledge the stranding networks from France (Observatoire PELAGIS), Spain (CEMMA), and Portugal (SPVS) for providing us cetacean samples. We also thank A. F. Guerra and F. Read from the Instituto de Investigaciones Marinas (C.S.I.C) in Vigo, Spain, and W. Dabin from the Observatoire PELAGIS in La Rochelle, France, for the age determination of the individuals. We also wish to thank C. Pignon-Mussaud from the Cellule Géomatique (UMR LIENSs) for providing the map of the study area and M. Kalombo from the Centre Commun d’Analyses (Fédération de Recherche en Environnement pour le Développement Durable FR 3097 CNRS-IFREMER-Université de La Rochelle) for running part of the trace element analyses. This work has been funded by the CPER 13 (Contrat de Plan Etat Région) through a post-doctoral grant to AA and PMF acknowledges support from the Portuguese Foundation for Science and Technology of the Government of Portugal (SFRH/BD/36766/2007).publishe

Lead contamination of small cetaceans in European waters – The use of stable isotopes for identifying the sources of lead exposure

International audienceLead concentrations and isotopic composition have been measured in bone and teeth of small cetaceans belonging to three species (Delphinus delphis, Phocoena phocoena and Stenella coeruleoalba), to evaluate the toxicological risk and to determine sources of lead in the European waters. Lead concentrations, far lower than threshold value inducing toxic effects in human, were higher in teeth than in bones, but highly correlated between the two tissues (r = 0.92, p < 0.001). Large variations of 206Pb/207Pb values in bone tissue showed that cetaceans must be submitted to various atmospheric influences. No geographical differences appeared which is consistent with studies on their distribution indicating seasonal movements between Brittany waters and the Bay of Biscay. The negative correlation between 206Pb/207Pb ratios and age of the individuals reflected the decrease in the production of alkyl lead in Europe, i.e., the increasing use of unleaded gasoline

Les évolutions passées et futures du climat de la Nouvelle-Calédonie

Les longues séries d'observations de températures et de précipitations de la fin du XXe siècle en Nouvelle-Calédonie ont été homogénéisées puis analysées. Les moyennes annuelles des températures minimales et maximales ont augmenté respectivement de 0,3 et 0,2 °C par décennie sur la période 1970-2009. Les effets futurs du changement climatique en Nouvelle-Calédonie ont été étudiés en effectuant une descente d'échelle par la méthode quantile-quantile à partir de simulations numériques réalisées pour le quatrième rapport du GIEC. Selon les scénarios d'émissions de gaz à effet de serre, l'augmentation des températures minimales et maximales se situerait entre +1,5 et +2,7 °C en un siècle, relativement à la période 1971-1999. Il apparaît également que les conditions de température du futur entraîneraient une augmentation de la fréquence des années météorologiquement favorables aux épidémies de dengue. Quant aux cumuls annuels de précipitations, aucune tendance significative n'apparaît, ni dans les observations, ni dans les projections

Xenobiotic and Immune-Relevant Molecular Biomarkers in Harbor Seals as Proxies for Pollutant Burden and Effects?

Harbor seals are exposed to increasing pressure caused by anthropogenic activities in their marine environment. Persistent organic pollutants (POPs) and trace elements are hazardous contaminants which accumulate in tissues of harbor seals. POPs and trace elements can negatively affect the immune-system and have been reported e.g. to increase susceptibility to viral infections in seals. Biomarkers of the xenobiotic metabolism, cytokines and heat-shock-protein as cell mediators of the immune-system were established to evaluate the impact of environmental stressors on harbor seals. Harbor seals (n=54) were captured on sandbanks in the North Sea during 2009 to 2012. Medicals including hematology were performed, RNAlater blood samples were taken and analyzed using quantitative Polymerase Chain Reaction. Normalized transcript copy numbers were correlated to hematology and POP concentration in blood, and trace metals in blood and fur