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Plastic debris has been recognised as a potential stressor for Antarctic marine organisms. In this study, the effects of surface charged polystyrene nanoparticles (PS NPs) on the immune cells (coelomocytes) of the Antarctic sea urchin Sterechinus neumayeri were assessed through in vitro short-term cultures. The behaviour of anionic carboxylated (PS-COOH) and cationic amino-modified (PS-NH2) NPs in filtered natural sea water (NSW) from King George Island (South Shetland Islands) was characterised by dynamic light scattering. Cellular morphology, NP uptake, phagocytic capacity and gene expression were evaluated after 6 and 24 h of exposure to 1 and 5 µg mL−1 PS NPs. Secondary characterisation showed an initial good dispersion of PS NPs in NSW, followed by nano-scale aggregation after 24 h. Both PS NPs affected cellular phagocytosis and generated an inflammatory response against oxidative stress and apoptosis at the molecular level. Fluorescently labelled PS-COOH aggregates were internalised by phagocytes and associated to the modulation of genes related to external challenges, antioxidant responses and cell protection against stress and apoptosis. Exposure to PS-NH2 caused a strong decrease in phagocytic capacity and the formation of cellular debris at 5 µg mL−1 after 24 h, but low gene modulation, suggesting a threshold in coelomocytes defence ability against PS-NH2. This study represents the first attempt to assess the impact of nanoplastics on Antarctic marine organisms. Our findings demonstrate that PS NPs with different surface charges constitute a challenge for S. neumayeri immune cells. [ABSTRACT FROM AUTHOR]

In order to assess the impact of nanoplastics on marine species, polystyrene nanoparticles (PS NPs) have been largely used as model particles. Here we studied the effects of 50 nm amino-modified PS-NH2 on Mediterranean sea urchin Paracentrotus lividus immune system cells (coelomocytes) in the presence of celomic fluid (CF) and at different NP concentrations (1, 5, 10, and 25 μg mL−1) and experimental conditions (absence or presence of EDTA). PS-NH2 acquired a protein corona once incubated with CF, dominated by the toposome precursor protein (TPP). In short-term cultures, a significant concentration- and time-dependent decrease in lysosomal membrane stability and apoptotic-like nuclear alterations were observed in phagocytes upon exposure to PS-NH2 (10 and 25 µg mL−1) in CF but they resulted abolished in the presence of EDTA confirming the role of TPP in triggering PS-NH2-coelomocytes interaction and toxicity. PS-NH2 did not alter MXR phenotype but the observed dose-dependent decrease in calcein accumulation suggests the ability of PS-NH2 to affect pump's efflux activity. Overall results encourage additional studies on positively charged nanoplastics, since the observed effects on sea urchin coelomocytes as well as the TPP corona formation might represent a first step for addressing their impact on sensitive marine species. [ABSTRACT FROM AUTHOR]

Migratory birds are considered one of the main sources for West Nile virus (WNV) introduction into European countries. Following the WNV epidemic in the late summer of 1998 in a marshy area of Tuscany (Padule of Fucecchio), an extensive ornithological surveillance programme was carried out in the infected areas from 2006 to 2008. Several species of migratory and resident birds were trapped, sampled and serologically tested. The results of this surveillance programme gave a useful indication of potential sources of WNV re-introduction and spread into Italy. The area under study was also investigated and classified into ecological areas through satellite image processing. In August 2008, the WNV infection re-emerged in Italy in the area surrounding the Po river delta, involving three regions: Lombardy, Emilia Romagna and Veneto. Several surveillance activities were immediately put in place, including the extensive monitoring of wild birds found dead or trapped in the framework of other surveillance programmes. These activities were also prolonged in the 2009, when the virus circulation re-occurred at the border of the area already infected in 2008. The possible epidemiological role of the different species of migratory and resident birds is discussed, in relation to the different ecological patterns identified in the area and their potential ability to introduce, spread and support the endemization of WNV infection. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the interaction of a common polycyclic musk fragrance, namely tonalide (AHTN), with the detoxification gene family CYP1A, by looking at both gene transcription (cyp1a) and enzyme activity (7-ethoxyresorufin-O-deethylase; EROD) in the PLHC-1 fish cell line. Time-dependent (6 and 24 h) exposure experiments with three doses of AHTN (1 nM, 10 nM and 2 μM) were performed. Co-exposure with known CYP1A inducers such as benzo[a]pyrene (B[a]P) and 3,3′-4,4′,5-pentachlorobiphenyl (PCB 126) was also investigated. A slight induction of cyp1a gene transcription was observed after 6 h, but not at 24 h. At 6 h, 40–45% of reduction of cyp1a transcription was observed in co-exposure with B[a]P and PCB 126 compared with single inducers. Complete recovery was observed after 24 h. No effect on EROD activity by AHTN was observed in either single exposure and co-exposure. AHTN seemed not to affect CYP1A at the gene or enzyme level, but in co-exposure with inducers ATHN seems able to reduce detoxification capability within a short time. [ABSTRACT FROM PUBLISHER]

An integrated ecotoxicological study based on bioaccumulation and biomarker responses in sea urchin, mussel, and fish was conducted in Vlora Bay (Albania). Despite several past industrial activities and current increase of anthropogenic impact characterising Vlora Bay, no ecotoxicological data have been published so far, underlining the need to investigate the area and to validate the ecotoxicological approach. Heavy metals, polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OC), and polychlorinated biphenyls (PCBs) were measured in native sea urchin ( Arbacia lixula), Mediterranean mussel ( Mytilus galloprovincialis), and red mullet ( Mullus barbatus). Several biomarkers such as expression of heat-shock proteins (HSP-70) in sea urchin (PCR), detoxification enzyme activities and apoptosis in mussels, and acetylcholinesterase (AChE) activity in mussels and red mullet were investigated. Overall, ecotoxicological data suggest an environmental quality of Vlora Bay resembling a marine protected area except for levels of Cd, Ni, and Hg in mussels and red mullet gonads; these results are in agreement with past industrial activities. OC pesticides were found to be below the detection limit in sea urchin. PCB levels were very low (4.13-13.87 ngg−1 fresh weight) both in mussels and fish, while PAHs were similar to those reported for moderately impacted areas. No exposure to neurotoxic pesticides (physiological AChE activities) or to cytotoxic contaminants (low apoptosis frequency: <1%) can be inferred both in mussels and fish. . Detoxification enzyme activities in mussels were highly similar compared with those reported for low-impact areas. The results of the present ecotoxicological study on Vlora Bay also support its suitability in environmental quality assessment of marine coastal areas. [ABSTRACT FROM AUTHOR]

An integrated ecotoxicological study based on bioaccumulation and biomarker responses in sea urchin, mussel, and fish was conducted in Vlora Bay (Albania). Despite several past industrial activities and current increase of anthropogenic impact characterising Vlora Bay, no ecotoxicological data have been published so far, underlining the need to investigate the area and to validate the ecotoxicological approach. Heavy metals, polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OC), and polychlorinated biphenyls (PCBs) were measured in native sea urchin (Arbacia lixula), Mediterranean mussel (Mytilus galloprovincialis), and red mullet (Mullus barbatus). Several biomarkers such as expression of heat-shock proteins (HSP-70) in sea urchin (PCR), detoxification enzyme activities and apoptosis in mussels, and acetylcholinesterase (AChE) activity in mussels and red mullet were investigated. Overall, ecotoxicological data suggest an environmental quality of Vlora Bay resembling a marine protected area except for levels of Cd, Ni, and Hg in mussels and red mullet gonads; these results are in agreement with past industrial activities. OC pesticides were found to be below the detection limit in sea urchin. PCB levels were very low (4.13-13.87 ngg-1 fresh weight) both in mussels and fish, while PAHs were similar to those reported for moderately impacted areas. No exposure to neurotoxic pesticides (physiological AChE activities) or to cytotoxic contaminants (low apoptosis frequency: ,1%) can be inferred both in mussels and fish. . Detoxification enzyme activities in mussels were highly similar compared with those reported for low-impact areas. The results of the present ecotoxicological study on Vlora Bay also support its suitability in environmental quality assessment of marine coastal areas. [ABSTRACT FROM AUTHOR]

The aim of the present study is to investigate the endocrine disrupting potential of the explosive 2,4,6-trinitrotoluene (TNT) on marine organisms using the European eel (Anguilla anguilla Linnaeus, 1758) as model fish species. Crucial brain steroidogenic parameters such as the estrogen receptors (ERs), P450 aromatase (CYP19), steroidogenic acute regulatory (StAR) protein and P450-mediated cholesterol side-chain cleavage (P450scc) enzyme were selected as potential biomarkers for the assessment of TNT endocrine disrupting potential. Juvenile European eels were exposed for 6 and 24 h to 0.5, 1 and 2.5 mg/l nominal concentration of TNT dissolved in dimethyl sulfoxide (DMSO). ERα, CYP19, StAR protein and P450scc genes expression were quantified using real-time PCR. Exposure to TNT altered the expression of ER gene at the lowest TNT concentration after 6 h of exposure, while after 24 h gene expression levels increased respect to controls only in eels at the maximum TNT dose (2.5 mg/l). A significant increase of CYP19 gene expression occurred after 6 h in all eels exposed to TNT compared to controls. On the opposite at 24 h, CYP19 expression seems reduced in eels exposed to 0.5 and 1mg TNT/l compared to 6 h, while no changes were observed at the highest dose (2.5 mg/l). Both StAR and P450scc gene expression were decreased at 6 h in eels exposed to 0.5 and 1mg TNT/l, while at 2.5 mg TNT/l, the gene expression levels were restored to background level. No further modulation was evident after 24 h for both genes. The overall results indicate the ability of TNT to affect neurosteroidogenic pathways. [ABSTRACT FROM AUTHOR]

Eels are exposed to pollutants due to their unusual life cycle and are vulnerable to contamination associated with sediment due to their diet, feeding habits and territoriality. Since the 1980s, a decline in American and European eel populations has been recorded. The causes of this decline still are unknown but pollution from domestic and industrial effluents is known to be involved. Since little data is available on PCB contamination in eels from Italian waters, PCBs were measured in muscle of Anguilla anguilla captured in 2001 in two brackish ecosystems of the Mediterranean: the lagoons of Orbetello and Santa Giusta (Italy). PCBs were higher in samples from Orbetello lagoon than in those detected from Santa Giusta lagoon ( P < 0.05). Congener and isomer analyses indicated Aroclor 1260 as a likely source of PCBs in the Orbetello and Santa Giusta samples. Only the toxic equivalents (TEQs) of mono-ortho PCBs were calculated. [ABSTRACT FROM AUTHOR]

In order to gain preliminary knowledge about the threat to marine ecosystems due to leakage of chemical warfare agents (CWAs) and other pollutants from rusting bombshells on the seabed, a case study was conducted in a dumping area in the southern Adriatic Sea (depth 200–300 m). Following electroacoustic and magnetometric surveys of the CWA dumping area, an integrated ecotoxicological approach was used. This approach was based on analysis of CWA residues and their metabolites, including arsenic, in sediment and organisms, as well as multimarker methodology including the Health Assessment Index, histological lesion analysis and enzyme assays. Two sentinel species were selected, the blackbelly rosefish [ Helicolenus dactylopterus (Delaroche, 1809)] and the European conger ( Conger conger L., 1758). Sediment analysis revealed the presence of CWA degradation products, including 1-4-thioxane and 1-4-dithiane. Tissues of fish from the CWA dumping site showed higher levels of arsenic than those from the reference site. Neither CWAs nor their metabolites were detected in fish tissues. Arsenic levels recorded in blackbelly rosefish were well above those reported for other fish species from the southern Adriatic, much higher than the FDA limit for food (2.6 mg kg−1) and close to the LD50 calculated for mammals (20 mg kg−1 body weight). The presence of pollutants in the CWA dumping site was also confirmed by pathological lesions in both species and EROD activity, two to three times higher than in fish from the reference site (16.45±8.08 and 8.05±5.87 pmol min−1 mg protein−1 in blackbelly rosefish and 269±24.92 and 78.71 pmol min−1 mg protein−1 in European conger, respectively). Cholinesterase activity seemed unaffected in muscle of both species, whereas in brain they were one-third of those recorded in fish from the reference site (14.22±10.05 and 72.87 nmol min−1 mg protein−1, respectively). This suggests that acetylcholinesterase is sensitive to CWAs. In conclusion, the agreement of all the chemical and biological parameters investigated suggests that the integrated ecotoxicological approach used is appropriate to reveal the presence and biological effects of CWAs in the marine ecosystem. [ABSTRACT FROM AUTHOR]

The European eel ( Anguilla anguilla ) is a euryaline fish suitable for investigating exposure, accumulation patterns and biological effects of lipophilic pollutants such as polychlorinated biphenyls (PCBs). Eels were collected from the Orbetello Lagoon (Tyrrhenian coast of Italy) and injected with increasing doses of Aroclor 1254 to better characterise EROD activity as biomarker in eels from Mediterranean brackish environments. Fish muscle was analysed for PCB content and EROD activity was measured in liver microsomial fraction. Significant differences of PCB levels were observed in exposed fish ( p  < 0.05) while EROD activity increased significantly reaching the highest values at the maximum dose of 50 mg/Kg ( p  < 0.001). Highly positive correlation ( r  = 0.82; p  < 0.01) was found between PCB content and EROD activity. Isomer profiles showed decreases in hexa-CBs. The European eel is confirmed to be a useful sentinel species for assessing pollution in brackish environments whereas EROD activity is characterised as a sensitive biomarker of exposure for PCB mixtures. [ABSTRACT FROM AUTHOR]

The article presents the detection of nonylphenols being discharged by urban and industrial wastewater into aquatic environment. The chemicals nonylphenol polyethoxylates are discharged into aquatic environments where they break into the by-products nonylphenol ethoxylates (NPE) and into the final nonylphenol (NP). Studies indicate that these molecules act as oestrogen mimics affecting the endocrine system of sexually mature fish (endocrine disruption). The bioaccumulation of NP and NPE has been studied mainly in freshwater fish species since mostly exposed to sewage treatment plant effluents (STPEs). Samples of Zosterisessor ophiocephalus were collected in winter 1998 (December) and spring 1999 (March) using fish traps positioned in three different sites of the Lagoon.

The concentrations of non-ortho-, mono-ortho-, di-ortho-substituted polychlorinated biphenyls (PCBs) and DDTs (pp′-DDT and pp′-DDE) were measured in fish and bed sediments of the Po River. Three species of cyprinids, nase (Chondrostoma söetta), chub (Leuciscus cephalus), and barbel (Barbus plebejus), were captured in the major Italian river, upstream and downstream from the confluence of the Lambro River. The two carnivorous species, chub and barbel, were found to be the most contaminated, showing muscle tissue concentrations up to eightfold higher than the corresponding upstream fish. DDT concentrations were parallel to PCB changes although at lower values. Despite the increased contamination caused by the input from the Lambro tributary, when fish PCB loads are converted to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) equivalents using piscine toxic equivalency factors (TEFs), no specific hazard can be associated to the limited toxic potentials of PCBs. Although these results seem to minimise the risk for the fish community of the Po River, the presence of other organochlorines and halogenated hydrocarbons is very probable in the downstream area, and a more exhaustive hazard assessment, based on further studies, should be undertaken. [ABSTRACT FROM AUTHOR]

The aim of this study was to test a multi response biomarker approach for evaluating toxicological risk due to some of the main contaminants in the Mediterranean benzo a pyrene, polychlorobiphenyls and methyl mercury , using the Mediterranean crab Carcinus aestuarii as bioindicator organism. Forty crabs were injected with different doses of these contaminants. Several molecular, biochemical and genotoxic biomarkers were tested in different tissues and biological materials. The main conclusions were: 1 hepatopancreas, gills, haemolymph and excreta seem to be useful for biomarker studies in this species; 2 several biochemical, molecular and genotoxic biomarkers were found suitable for testing in these tissues; 3 several biomarkers were found suitable for evaluating chemical stress due to different Mediterranean contaminants. [ABSTRACT FROM AUTHOR]