PCDD/F and dioxin-like PCB bioaccumulation by Manila clam from polluted areas of Venice lagoon (Italy).

POP bioaccumulation pathways in the clam Tapes philippinarum were examined for two years from juveniles to adult size. Two polluted sites, one with sandy sediment, the other muddy were compared with a reference site characterized by low contamination levels. Juvenile clams coming from a hatchery were reared both on the sediment and in nets suspended at 30 cm from the bottom.

DNA damage and transcriptional changes in the gills of mytilus galloprovincialis exposed to nanomolar doses of combined metal salts (Cd, Cu, Hg).

Aiming at an integrated and mechanistic view of the early biological effects of selected metals in the marine sentinel organism Mytilus galloprovincialis, we exposed mussels for 48 hours to 50, 100 and 200 nM solutions of equimolar Cd, Cu and Hg salts and measured cytological and molecular biomarkers in parallel. Focusing on the mussel gills, first target of toxic water contaminants and actively proliferating tissue, we detected significant dose-related increases of cells with micronuclei and other nuclear abnormalities in the treated mussels, with differences in the bioconcentration of the three metals determined in the mussel flesh by atomic absorption spectrometry. Gene expression profiles, determined in the same individual gills in parallel, revealed some transcriptional changes at the 50 nM dose, and substantial increases of differentially expressed genes at the 100 and 200 nM doses, with roughly similar amounts of up- and down-regulated genes.

POPs in the Lagoon of Venice: budgets and pathways.

Dioxins and furans (PCDD/Fs), polychlorobiphenyls (PCBs) and hexachlorobenzene (HCB) in the ecosystem of the Lagoon of Venice were studied, in order to provide a general picture of conditions in the lagoon in terms of contamination by persistent organic pollutants (POPs). We present here novel data on atmospheric deposition, water, sediment and clam samples collected in the lagoon during the period January 2001-December 2004. Atmospheric deposition was sampled monthly at six sites located both close and far from large industrial and urban sources.

Atmospheric fall-out of POPs (PCDD-Fs, PCBs, HCB, PAHs) around the industrial district of Porto Marghera, Italy.

In order to estimate the importance of atmospheric fall-out of persistent organic pollutants (POPs) around the industrial district of Porto Marghera, Italy, atmospheric depositions of POPs were collected using bulk samplers inside the Lagoon of Venice. Seventy-seven atmospheric deposition samples were collected monthly over a 12-month period (March 2003-March 2004) at seven sites located close to the industrial area of Porto Marghera. Samples were analysed by HRGC/HRMS for PCDD-Fs, PCBs, HCB and PAHs.