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Octopus vulgaris constitute an important part of most suitable marine resources for human consumption, however, they can represent a source in chemical contaminants intake such as heavy metals. In this scenario, the aim of the study was the evaluation of the concentration of lead (Pb), cadmium (Cd) and mercury (Hg) in the muscle and digestive gland of octopus caught from two different locations along Campania coast (Castellammare di Stabia and Napoli) and the estimation of their weekly human intake derived from the ingestion of octopus. Analysing 38 samples showed a higher concentration of Pb in the muscle of octopus in Castellammare di Stabia than in Napoli. No statistical differences were reported for Cd, Pb and Hg concentrations in the digestive gland of octopus between two sampling sites. Differences were observed between the two tissue types, with a higher level of Cd and Pb observed in the digestive gland compared with the muscle. Noteworthy, the consumption of muscle from Castellammare di Stabia could increase Pb intake in heavy consumers of local octopus. In conclusion, the present work determines that it is important to improve strategies to minimize environmental pollution sources in these areas.

The biological effect of seasonality on cadmium, lead and metallothionein contents was assessed in mussels Mytilus galloprovincialis from natural banks located along the coastline of the Gulf of Naples (Campania, Italy). Heavy metals and metallothionein concentrations were measured in digestive and reproductive glands. The results showed a clear correlation between metallothionein content and the reproductive gland status determined during the seasons; on the contrary, no correlation was found between metallothionein and metal contents. Data allow us to hypothesize that metallothionein functions go beyond metal detoxification, thus opening new scenarios for these proteins in invertebrates. The effect of seasons on metals concentration in mussel tissues showed similar seasonal patterns between the sites, regardless of their anthropogenic impacts. Cadmium content was not strictly related to seasonal periods, whereas lead content was significantly lower in summer. The results also indicate that the metal contents in mussels from the Gulf of Naples do not represent a risk to human health, even in the period of their maximum accumulation, and that the relaying of mussels before marketing could improve the animal stress conditions, but having a slight effect on metal excretion., (Copyright © 2014 Académie des sciences. Published by Elsevier SAS. All rights reserved.)

Possible xenoestrogenic effects were investigated, for the first time, in two bivalve species from the Lagoon of Venice (Italy): the clam Tapes philippinarum and the cockle Cerastoderma glaucum. Bivalves were collected far from their reproductive phase at the very early stage of gametogenesis (January), and in the pre-spawning period (June) in six sites. Vitellogenin (Vg)-like proteins (a biomarker of exposure to estrogenic compounds) were measured by the alkali-labile phosphate method (ALP), in both haemolymph and digestive gland from males and females (when it was possible to distinguish sex by microscopic observation of gonadal tissue). Haemolymph calcium concentrations (a parameter considered closely related to the presence of Vg-like proteins) and the bivalve condition index (CI) were also measured. In both seasons, bivalves collected at Campalto (near a sewage treatment plant) and Marghera (a highly contaminated area) had higher Vg-like protein levels, particularly in haemolymph, than animals from the other sampling sites. Interestingly, CI had high values in these polluted sites. In June only, Vg-like proteins and Ca(2+) levels in haemolymph exhibited similar trends in both bivalve species at most sampling sites. The responsiveness of bivalves to environmental xenoestrogens was higher in June, allowing better discrimination among sites. The present study demonstrates that animals from highly polluted areas have increased Vg-like protein levels. As endocrine disruption due to exposure to estrogenic compounds may cause fertility reduction, alterations in the sex ratio, and a decrease in reproductive rate, a condition of potential risk for bivalve populations in estuarine areas is highlighted.

The autometallographic approach was applied to three filter-feeder bivalves from differently polluted sites of the Lagoon of Venice. The area density (AD) values of black silver deposits (BSDs) were therefore seasonally quantified by image analysis in digestive cell lysosomes. Sediments were characterised in terms of grain size, organic content and metal concentrations (Cd, Cu, Ni, Pb, Zn). The physiological status of the bivalves was also evaluated by applying the "survival in air" test as a generic stress index. Chemical results showed that Zn contributed to the total metal load for more than 60% in sediments and for 85%-94% in mussel and clam digestive glands, respectively (data processed from published results obtained on the same samples). Regression analyses between extent of BSDs and both total metal and Zn concentrations in digestive gland followed a linear pattern in mussels and clams, but not in arks. Similarly, in mussels and clams only, BSD amount was significantly correlated with total metal concentrations in sediments according to a logarithmic model. Consequently, results obtained from autometallography can discriminate sites on the basis of their metal pollution levels, like chemical analyses on both sediments and digestive glands, evaluations being supported by the results of the physiological stress index. As a conclusion, it is suggested that autometallography in bivalves may provide overall estimates of metal fractions moving from sediments towards organisms through the ingestion of metal-enriched particles. Future work is needed to define the bioaccumulation model in arks and to clarify their possible use as metal biomonitors.

In developed countries, estuarine environments are often subjected to chemical pollution, whose biological impact is profitably evaluated by the use of multi-biomarker approaches on sentinel species. In this paper, we investigate genotoxicity and lysosomal alterations in the Mediterranean mussel (Mytilus galloprovincialis), from the estuary of the River Cecina (Tuscany, Italy), selected as "pilot basin" within the Water Frame Directive (2000/60 European Community). Both native and 1 month transplanted mussels were used in order to compare these two approaches in terms of sensitiveness of specific biomarker responses. Genotoxic effects were evaluated as strand breaks, by single cell gel electrophoresis (or Comet assay), and as chromosomal alterations, by the micronucleus test in gill cells. Lysosomal alterations were assessed by the neutral red retention time (in haemocytes), lipofuscin accumulation and ultrastructure (in digestive cells). Heavy metal bioaccumulation was also analysed. Mussels from the River Cecina showed a general alteration of all the biomarkers investigated, accompanied by an elevation of tissue metal levels. However, some differences in specific responses occurred between transplanted and native mussels. Early biomarkers, such as those based on DNA and lysosomal membrane integrity, were induced at similar degree in native and transplanted mussels; while alterations resulting from cumulative events, as the increase of micronuclei frequency were much more elevated in native specimens (23.1+/-7.6) than in transplanted (9.3+/-4.7) and reference ones (5.8+/-5.2). Similarly, the comparison between lipofuscin accumulation and mean lysosomal diameter in impacted and control sites, gave significant differences exclusively with transplanted mussels. These results suggest that the parallel use of caged and native mussels in environmental biomonitoring can improve the characterization of the study area.

Heavy metal pollution is known to be widespread in the sediments of the Lagoon of Venice. Therefore, physiological parameters influenced by this form of contamination were examined. The bivalve molluscs blue mussel (Mytilus galloprovincialis), ark clam (Scapharca inaequivalvis), and Japanese littleneck (Tapes philippinarum) were sampled in two sites (Marghera, Chioggia) every 3 months for 1 year. The digestive gland and gills of each bivalve were analyzed. The concentrations of essential and nonessential metals (including chromium, manganese, iron, cobalt, nickel, copper, zinc, and cadmium) were determined. Because glutathione and metallothioneins (MTs) are involved in metal homeostasis and detoxification, their concentrations were evaluated in relation to metal concentrations. Results show that (1) all three studied species accumulate metals to a considerable extent, with some species-specific differences between the digestive gland and gills; (2) gills are a good tissue to evaluate pollution by examining the MT content. In particular, the correlation between Zn and MT levels in the gills indicates that M. galloprovincialis and S. inaequivalvis are sentinel organisms and can be used specifically for Zn pollution; (3) T. philippinarum accumulates Cu in the digestive gland more readily than the other two bivalves and therefore has the highest MT.

The aim of this study was to investigate the cellular and biochemical response of mussels, Mytilus galloprovincialis, transplanted from a relatively pristine site to a polluted one and vice versa in the Lagoon of Venice (northeast of Italy) and to apply auto-metallography, a rapid and sensitive histochemical technique, to determine the bio-available fraction of heavy metals accumulated in the body tissues of organisms. Animal digestive glands have been used for morphological analyses (lysosomal volume, surface and numerical density, mean epithelial thickness, mean diverticular and luminar radius), autometallographical black silver deposits quantification and biochemical assays (superoxide dismutase and catalase activity). Furthermore, heavy metal content was determined by atomic absorption spectrophotometry (AAS) using standard procedures. The overall results indicate a direct influence of the environment in the thinning of the digestive cells and in the increasing number of lysosomes in mussels from the more polluted site. These data are in agreement with the metal content in digestive cell lysosomes as determined by autometallography, whereas AAS measurements show less significant differences.

Identification of YTX and homoYTX in natural phytoplankton populations containing significant amounts of Gonyaulax polyedra and determination of detailed toxin profiles of mussels (Mytilus galloprovincialis) periodically collected from two sites of the Northern Adriatic coast from February to October 1997 was performed by LC-FLD following derivatization with ADAM or DMEQ-TAD and LC-MS and LC-MS-MS. OA and YTX concentrations were recorded in the range 0.11-2.31 and 0.18-9.02 microg per g of hepatopancreas, respectively. HomoYTX was also detected both in phytoplankton and mussel samples.

In the framework of a wide monitoring programme on the presence of heavy metals in marine organisms caught in the South Adriatic Sea, cadmium and total mercury concentrations were determined in flesh and hepatopancreas of 512 specimens of two species of cephalopods. The aim of the study was to establish the quality of the marine food with respect to the health of consumers and to investigate cadmium and mercury distribution in organisms representing different habitats. For both elements, higher levels were found in spider octopus (Octopus salutii) than in broadtail squid (Illex coindeti). Between the two different tissues analysed, higher concentrations were observed in hepatopancreas than flesh. According to the rules in force, no flesh sample showed cadmium and total mercury concentrations exceeding the peak permitted values of 2 mg/kg wet wt and 0.5 mg/kg wet wt respectively.

The diarrhetic shellfish toxin composition in the hepatopancreas of mussels from the northern Adriatic sea was investigated. The major toxins were shown to be yessotoxin (YTX), homoyessotoxin (homoYTX) and 45-hydroxyyessotoxin (45-OHYTX), identified by comparison of their chromatographic and spectral properties with those reported in the literature.

A collaborative study was performed on Mediterranean mussels (Mytilus galloprovincialis) exposed to a wide dose-range (0.5-1000 ppb) of benzo[a]pyrene (B[a]P). We selected this model polycyclic aromatic hydrocarbon in order to confirm the formation of a specific DNA adduct, previously detected in gill DNA, and to clarify the in vivo effects of this mutagenic chemical requiring host-metabolism in mussels. B[a]P concentration reached consistently higher values in the digestive gland than in other analyzed tissues of mussels exposed to B[a]P for 2 or 3 days. With the exception of some values at 1000 ppb of B[a]P. DNA adduct levels increased significantly with the dose in gills and digestive gland and ranged from 0.054 to 0.789 adducts per 10(8) nucleotides (mean values per dose-point). Conversely, more complex dose-response relationships were found by detecting in parallel the levels of an oxidative DNA lesion (8-OHdG) and of CYP1A-immunopositive proteins (the latter measured in the digestive gland only). Overall, the formation of DNA adducts, the evidence of oxidative DNA damage, and changes in CYP1A-immunopositive protein levels support the hypothesis that B[a]P can induce DNA damage in mussels through a number of different molecular mechanisms.