Search

The common mussel Mytilus galloprovincialis was selected as unique biomonitor species to implement a regional monitoring programme, the CIESM Mediterranean Mussel Watch (MMW), in the Mediterranean and Black Seas. As of today, and upon standardization of the methodological approach, the MMW Network has been able to quantify 137Cs levels in mussels from 60 coastal stations and to produce the first distribution map of this artificial radionuclide at the scale of the entire Mediterranean and Black Seas. While measured 137Cs levels were found to be very low (usually <1Bqkg−1 wet wt) 137Cs activity concentrations in the Black Sea and North Aegean Sea were up to two orders of magnitude higher than those in the western Mediterranean Basin. Such effects, far from representing a threat to human populations or the environment, reflect a persistent signature of the Chernobyl fallout in this area. [Copyright &y& Elsevier]

The concentrations of Cd, Cu, Fe, Pb and Zn were measured in holothuroids Holothuria tubulosa collected during different seasons and at several depths in three N W Mediterranean Posidonia oceanica meadows (Calvi, Corsica; Ischia, Italy; Marseille, France). Metals were found to be selectively distributed among the holothuroid body compartments (i.e. body wall, gut, and haemal system). Among the sources of variation taken into account, the major part of the variability observed in metal concentrations was associated to the body compartment factor, then to the seasonal one and, finally, to the geographical and bathymetric factors. Our results suggest that, if one uses H. tubulosa as a bioindicator species for surveying and monitoring metal contamination in the Mediterranean P. oceanica meadows, attention should be paid to compare only concentrations measured in the same body compartments of individuals collected during the same period of the year. Body compartments that should be preferably considered for metal analyses are the haemal system and, secondarily, the gut (i.e. the compartments concentrating metals most efficiently). Due to the peculiar ecological characteristics of H. tubulosa (i.e. a deposit feeder living in close relationships with the sediments), this species could be effectively used to complement the small set of bioindicators available so far for surveying metal contamination in the P. oceanica ecosystem (viz. the phanerogam P. oceanica itself and the grazing echinoid Paracentrotus lividus). [ABSTRACT FROM AUTHOR]