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Fish consumption is the principal source of intake of organochlorinated compounds in humans. Compared with other types of foods of animal origin, fish contain the highest levels of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins, and polychlorinated dibenzofurans, all of which are classified as highly toxic organochlorine compounds. Currently, lakes and fish farms in northern Italy are not regularly monitored for PCBs and dioxins in areas contaminated by industrial sources, partially because of the high costs of traditional analytical methods that limit the number of samples to be analyzed. The DR-CALUX cell bioassay is based on the uptake of the cellular aryl hydrocarbon receptor (AhR) for dioxins and dioxin-like compounds. The aim of this study was to assess the levels of dioxins and dioxin-like PCB contamination in Lake Maggiore and Lake Como, two lakes in northwestern Italy, and in nearby areas. The levels were quantified using the cell bioassay DR-CALUX and reference controls in two wild fish species, perch (Perca fluviatilis) and roach (Rutilus rutilus), and in a farmed species, rainbow trout (Oncorhynchus mykiss). Tissue samples collected from the farmed rainbow trout were also submitted to immunohistochemical analysis of CYP1A expression as a marker for environmental pollutant-induced liver damage. The levels of dioxins, furans, and dioxin-like PCBs were all below the maximum levels and action limits set by European Union Regulation, suggesting no risk for human health associated with the consumption of the fish species caught or farmed in these areas. [ABSTRACT FROM AUTHOR]

Information regarding chemical pollutant levels in farmed fish and shellfish, along with the risks associated with their consumption is still scarce. This study was designed to assess levels of exposure to 21 trace elements in fish ( Dicentrarchus labrax ), mussels ( Mytilus galloprovincialis ) and oysters ( Crassostrea gigas ) collected from aquaculture marine ecosystems of the northwestern Mediterranean Sea. Metal concentrations showed great variability in the three species; the highest values of the nonessential elements As and Cd were found in oysters while the highest levels of Al, Pb and V were found in mussels. The essential elements Cu, Mn and Zn were highest in oysters, but Fe, Cr, Ni, Se, Co and Mo levels were highest in mussels. Fish had the lowest concentrations for all trace elements, which were at least one order of magnitude lower than in bivalves. The rare earth elements cerium and lanthanum were found at higher levels in mussels than in oysters, but undetectable in fish. The maximum values set by European regulations for Hg, Cd and Pb were never exceeded in the examined samples. However, comparing the estimated human daily intakes (EHDIs) with the suggested tolerable copper and zinc intakes suggested a potential risk for frequent consumers of oysters. Similarly, people who consume high quantities of mussels could be exposed to concentrations of Al that exceed the proposed TWI (tolerable weekly intake). [ABSTRACT FROM AUTHOR]

Abstract: The accumulation of heavy metals in freshwaters has direct consequences to man and ecosystem. Thus, in this study, the concentrations of mercury, cadmium, lead, arsenic and chromium in organs of the predator European catfish (Silurus glanis) were investigated. Samples were collected annually in five sites covering the area of the Po River (North Italy) between 2007 and 2009. Metals were differently distributed in the various organs, the highest concentrations of Hg were found in muscle and liver, Cd in kidney, Pb in gill and liver, as in muscle, and of Cr in gill and liver. Our survey found Hg exceeding the Maximum Levels (MLs) of 0.5ppm in 18% of samples, while Pb and Cd were lower than the MLs set by European regulations in muscle tissues (1881/2006/EC and 629/2008/EC). Hg concentrations were significantly related to sampling stations studied, according to the presence of many industrial activities in the catchment area of Bormida and Tanaro Rivers. The finding that Hg did not fit food fish legislation limits indicated that S. glanis flesh might not be utilised for human consumption. A close monitoring of metals pollution is strongly recommended especially in piscivorous fish, cause their bioaccumulation capacity. [Copyright &y& Elsevier]

Highlights: [•] The top predator Silurus glanis reflects the severe pollution by organic matter of Italian Rivers (Northern Italy). [•] 33.3% Of the analysed samples exceeded the maximum levels of 125ngg−1 fresh weight (fw) set by Regulation in fish muscle. [•] Po River registered the highest presence of NDL-PCB, with 50% of samples not compliant with EU ML. [•] The Σ6PCBs well represented total NDL-PCBs levels. [•] The contribution of PCB-153 and PCB-138 together was about 70% of the overall sum of the six congeners. [Copyright &y& Elsevier]

The Pacific oyster is one of the world's most widespread bivalves and a suitable species for biomonitoring trace elements in marine environments thanks to its bioaccumulation ability. As it is also an edible mollusc, concentrations of harmful elements in its tissues must be monitored. For these purposes, 464 wild individuals were collected from 12 sites along the Italian coasts. The concentration of fourteen trace elements (Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, Sn, Tl, and Zn) in their tissues was quantified. Among the three heavy metals, cadmium, lead, and mercury, none exceeded the maximum limit for in food set by European Union regulations but Cd in one sample from the Varano Lagoon resulted extremely close to this value. Contamination by Hg of the northern Adriatic and Orbetello Lagoons was also observed. Moreover, there was a positive association between the lagoon's environmental conditions and the bioaccumulation of this element in oysters. Despite the ban instituted 15 years ago on the use of Sn in antifouling paints, this element is still present in several marine environments, as demonstrated in the oysters sampled from harbour areas. Samples collected from harbours also showed very high concentrations of Cu and Zn due to the ability of oysters to accumulate these elements, which have replaced Sn in antifouling paints. Analysis of the samples from most sites indicated a low risk of human exposure to harmful elements through oyster consumption; nonetheless, chemical sanitary controls should focus primarily on Cd, Cu, and Zn. [ABSTRACT FROM AUTHOR]

Non-dioxin-like polychlorinated biphenyls (NDL-PCBs) contribute to the dietary intake of total PCBs. They are consumed via ingestion of contaminated fish and fishery products. Thus, it is important to quantify their levels in aquatic organisms in order to evaluate the risks associated with fish consumption by humans. In 2013, an advisory against consumption of fish from the River Roya (IT) was disseminated after NDL PCBs were found to exceed maximum levels set by EU Regulations. We investigated the presence of NDL PCBs in eel, trout and barbel from the River Roya. We found concentrations in the range of 9.2–27.6 ng g − 1 ww in barbel, 9.2–97.0 ng g −1 ww in trout and 9.0–239.5 ng g −1 ww in eel. The distribution of congeners among different species did not show significant variations and was characterized by a higher proportion of 153, 138 and 180 congeners, according to their high resistance to metabolic degradation. [ABSTRACT FROM AUTHOR]

The study of mercury and selenium bioaccumulation in fish is crucially important for evaluating the extent of contamination in freshwater environments, and the possible health risk posed for humans when the antagonistic interactions of these two elements are considered. Several factors affect the risk of mercury intake from fish consumption, including mercury levels, human consumption patterns, and sensitive populations (e.g., pregnant women, foetuses, young children and unknown genetic factors). The protective effects of selenium on mercury toxicity have been extensively publicised in recent years, particularly targeting fish consumers. In this study, mercury (Hg) and selenium (Se) concentrations were determined in the muscle of European catfish ( Silurus glanis ) collected from North Italian Rivers. Differences in mercury and selenium levels, as a function of size, gender and location were investigated. Hg was strongly related to length, gender and location, while Se levels are not dependent on fish size or location. The mean Se/Hg molar ratio was strongly affected by location, and significantly related to length and age. Selenium was in molar excess of mercury in all sites, with a rank order of mean Se/Hg molar ratio of the Parma River (2.55) > Po River (1.71) > Tanaro River (1.66) > Bormida River (1.36). However, in 37% of analyzed samples, Hg exceeded the maximum level set by 1881/2006/EC and 629/2008/EC in fish muscle. The molar ratio of Se/Hg was <1 only in the presence of significantly high Hg levels (>0.5 mg/kg), and therefore the mean molar ratio cannot be considered as a safety criterion in top predator fish. [ABSTRACT FROM AUTHOR]

Extensive screening analyses of perfluorooctane sulfonate and related perfluorinated compounds (PFCs) in biota samples from all over the world have identified PFCs as global pollutants and have shown their bioaccumulation into higher trophic levels in the food chain. Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are environmental contaminants belonging to a chemical group known as perfluorinated compounds. PFOS and PFOA are very persistent in the environment and bioaccumulate in humans. They are potential reproductive and developmental toxicants and are considered to be emerging endocrine disrupters. The United States Environmental Protection Agency (USEPA) considers both compounds to be carcinogenic and the European Food Safety Authority (EFSA) recently pointed out that they are associated with adverse health effects. Diet is considered the main source of exposure to PFCs, which have been found more frequently in fish and other seafood, compared to other food groups. In fact, aquatic ecosystems represent the final reservoir for PFCs due to their great affinity for sedimentary and living organic matter. In these systems, measured levels of persistent organic pollutants (POPs) could increase along the trophic web, ultimately affecting humans that consume aquatic species. In this study, PFOS and PFOA was detected by LC-MS/MS in muscle samples of Coregonus lavaretus (European whitefish) and Perca fluviatilis (European perch) collected from Lake Maggiore, a large lake located on the south side of the Italian Alps. PFOA was not found in any of the investigated samples above the limit of quantitation of 0.50ngg−1 fresh weight (fw), whereas PFOS was detected in all 90 samples with concentrations of up to 46.0ngg−1fw. Mean concentrations were 22.2ngg−1fw in P. fluviatilis and 20.0ngg−1fw in C.lavaretus. Comparison of our results with literature data on PFOS intake suggested that fish from Lake Maggiore may be a significant source of dietary PFOS exposure, even if the reported values were lower than the Total Daily Intake (TDI) proposed by EFSA. [ABSTRACT FROM AUTHOR]