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Assessment of biological effects of environmental pollution in Mersin Bay (Turkey, northeastern Mediterranean Sea) using Mullus barbatus and Liza ramada as target organisms
2016
Yılmaz, Doruk | Kalay, Mustafa | Dönmez, Erdem | Yılmaz, Nejat
The increasing emphasis on the assessment and monitoring of marine ecosystems has revealed the need to use appropriate biological indicators for these areas. Enzyme activities and histopathology are increasingly being used as indicators of environmental stress since they provide a definite biological end-point of pollutant exposure. As part of an ecotoxicological assessment of Mersin Bay, EROD enzyme activity and histopathological response in selected organs and tissues of two species of fish, Mullus barbatus (red mullet) and Liza ramada (thinlip grey mullet), captured from area were examined. Pollutant (Organochlorines (OC), alkylphenols (APs) and BPA) levels and biomarker responses in tissue samples were evaluated together for their potential to alter the metabolism and cellular aspects in liver and gonad. Elevated induction of EROD activity and histopathological alterations in contaminated samples from Mersin Bay was observed compared to reference site indicating the exposure to potential pollutants.
Mostrar más [+] Menos [-]Presence of trace metals in aquaculture marine ecosystems of the northwestern Mediterranean Sea (Italy)
2016
Squadrone, S. | Brizio, P. | Stella, C. | Prearo, M. | Pastorino, P. | Serracca, L. | Ercolini, C. | Abete, M.C.
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).
Mostrar más [+] Menos [-]High levels of microplastic ingestion by the semipelagic fish bogue Boops boops (L.) around the Balearic Islands
2016
Nadal, M.A. | Alomar, C. | Deudero, S.
For the first time this study reports on the presence of microplastics (1 nm to <5 mm) in the gastrointestinal tracts of small semipelagic fish (Boops boops) in the Balearic Islands (Mediterranean Sea) from March to May 2014. The results show microplastic ingestion in 68% of full stomach samples with an average of 3.75 items per fish. Only filament type microplastics were observed in B. boops full gastrointestinal tracts. The frequency of occurrence of microplastics was high, with values ranging from 42% to 80%, in comparison to the other ingested items. Spatial variability among locations is high, which suggests that this type of contamination is ubiquitously distributed and originates from multiple sources. The results are important and indirectly provide further evidence of the presence of microplastics, which can be ingested by biota, in the marine environment.
Mostrar más [+] Menos [-]Influence of trophic ecology on the accumulation of dioxins and furans (PCDD/Fs), non-ortho polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) in Mediterranean gulls (Larus michahellis and L. audouinii): A three-isotope approach
2016
Roscales, Jose L. | Vicente, Alba | Muñoz-Arnanz, Juan | Morales Diez de Ulzurrun, Laura | Abad, Esteban | Aguirre, Jose I. | Jiménez, Begoña
The impact of pollution caused by severe anthropogenic pressure in the Mediterranean Sea, an important biodiversity hotspot, requires continuous research efforts. Sources of highly toxic chemicals such as Persistent Organic Pollutants (POPs) are misunderstood in representative Mediterranean species, which limits our capability to establish proper conservation strategies. In the present study, eggs of Audouin's and yellow-legged gulls (Larus audouinii and L. michahellis) were used to investigate the trophic sources, as measured by δ13C, δ15N, and δ34S, of legacy POPs, in particular, polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) and non-ortho polychlorinated biphenyls (no-PCBs), as well as recently-regulated POPs, e.g., polybrominated diphenyl ethers (PBDEs). Special attention was paid to the usefulness of rarely-explored δ34S ratios in explaining POP exposure in wildlife, and δ34S was the isotopic ratio that best explained POP variations among gulls in most cases, thus demonstrating its usefulness for understanding POP exposure in wildlife. Significant relationships between stable isotope signatures and POP concentrations revealed increasing levels of no-PCBs and low halogenated PCDD/Fs and PBDEs in Mediterranean gulls as the consumption of marine resources increases. In contrast, highly chlorinated and brominated congeners appeared to preferentially accumulate in gulls feeding primarily on refuse from dump sites and terrestrial food webs. The use of suitable dietary tracers in the study of POPs in yellow-legged gulls revealed the importance of dump sites as a source of POPs in Mediterranean seabirds, which has not previously been reported. In contrast, the preferential accumulation through marine food webs of low chlorinated PCCD/Fs and no-PCBs, which show the highest toxic equivalents factors (TEFs), led to a significantly greater toxicological concern in Audouin's as compared to yellow-legged gulls. Audouin's gull exposure to POPs appears primarily related to the pelagic food webs commonly exploited by fisheries, highlighting the need for further research given the potential impact on human consumption.
Mostrar más [+] Menos [-]Fin whales and microplastics: The Mediterranean Sea and the Sea of Cortez scenarios
2016
Fossi, Maria Cristina | Marsili, Letizia | Baini, Matteo | Giannetti, Matteo | Coppola, Daniele | Guerranti, Cristiana | Caliani, Ilaria | Minutoli, Roberta | Lauriano, Giancarlo | Finoia, Maria Grazia | Rubegni, Fabrizio | Panigada, Simone | Bérubé, Martine | Urbán Ramírez, Jorge | Panti, Cristina
The impact that microplastics have on baleen whales is a question that remains largely unexplored. This study examined the interaction between free-ranging fin whales (Balaenoptera physalus) and microplastics by comparing populations living in two semi-enclosed basins, the Mediterranean Sea and the Sea of Cortez (Gulf of California, Mexico). The results indicate that a considerable abundance of microplastics and plastic additives exists in the neustonic samples from Pelagos Sanctuary of the Mediterranean Sea, and that pelagic areas containing high densities of microplastics overlap with whale feeding grounds, suggesting that whales are exposed to microplastics during foraging; this was confirmed by the observation of a temporal increase in toxicological stress in whales. Given the abundance of microplastics in the Mediterranean environment, along with the high concentrations of Persistent Bioaccumulative and Toxic (PBT) chemicals, plastic additives and biomarker responses detected in the biopsies of Mediterranean whales as compared to those in whales inhabiting the Sea of Cortez, we believe that exposure to microplastics because of direct ingestion and consumption of contaminated prey poses a major threat to the health of fin whales in the Mediterranean Sea.
Mostrar más [+] Menos [-]Heavy metal distribution in organic and siliceous marine sponge tissues measured by square wave anodic stripping voltammetry
2016
Illuminati, S. | Annibaldi, A. | Truzzi, C. | Scarponi, G.
May sponge spicules represent a “tank” to accumulate heavy metals? In this study we test this hypothesis determining the distribution of Cd, Pb and Cu concentrations between organic and siliceous tissues in Antarctic Demospongia (Sphaerotylus antarcticus, Kirkpatrikia coulmani and Haliclona sp.) and in the Mediterranean species Petrosia ficiformis. Results show that although, in these sponges, spicules represent about 80% of the mass content, the accumulation of pollutant is lower in the spicules than in the corresponding organic fraction. The contribution of tissues to the total sponge content of Cd, Pb and Cu is respectively 99%, 82% and 97% for Antarctic sponges and 96%, 95% and 96% for P. ficiformis, similar in polar and temperate organisms. These results pave the way to a better understanding of the role of marine sponges in uptaking heavy metals and to their possible use as monitor of marine ecosystems, recommend by the Water Framework Directive.
Mostrar más [+] Menos [-]Ecological assessment of a heavily human-stressed area in the Gulf of Milazzo, Central Mediterranean Sea: an integrated study of biological, physical and chemical indicators
2016
D'Alessandro, Michela | Esposito, Valentina | Giacobbe, Salvatore | Renzi, Monia | Mangano, Maria Cristina | Vivona, Pietro | Consoli, Pierpaolo | Scotti, Gianfranco | Andaloro, Franco | Romeo, Teresa
Marine environmental disturbance can be assessed directly from physical and chemical parameters, or indirectly by the study of indicator species. In this study, an integrated approach to monitor the Gulf of Milazzo, labeled as a highly contaminated site, is presented. A total of 83 samples were collected from hard and soft bottoms in 2010. In sum, 2739 specimens belonging to 246 taxa, two first records for the Tyrrhenian Sea (Micronephthys stammeri and Nicomache lumbricalis) and three nonindigenous species (Brachidontes pharaonis, Crassostrea gigas and Notomastus aberans) were recorded. Biodiversity and biotic indices and their relationship with sediment parameters and the level of pollutants were assessed to describe faunal assemblage and evaluate environmental quality. Pearson tests evidenced significant negative correlation between polychlorinated biphenyls (PCBs) and specific richness (p<0.10). A comparison of the standard and recorded biotic values showed that M-AMBI seems to be the index more representative of ecological quality status (EcoQ) in the Gulf of Milazzo. No evident signs were highlighted on the complex.
Mostrar más [+] Menos [-]Mercury concentrations in Northwest Atlantic winter-caught, male spiny dogfish (Squalus acanthias): A geographic mercury comparison and risk-reward framework for human consumption
2016
St. Gelais, Adam T. | Costa-Pierce, Barry A.
Mercury (Hg) contamination testing was conducted on winter-caught male spiny dogfish (Squalus acanthias) in southern New England and results compared to available data on Hg concentrations for this species. A limited risk-reward assessment for EPA (eicosapentanoic acid) and DHA (docosahexanoic acid) lipid concentrations of spiny dogfish was completed in comparison with other commonly consumed marine fish. Mean Hg concentrations were 0.19ppm (±0.30) wet weight. In comparison, mean Hg concentrations in S. acanthias varied geographically ranging from 0.05ppm (Celtic Sea) to 2.07ppm (Crete, Mediterranean Sea). A risk-reward assessment for Hg and DHA+EPA placed S. acanthias in both “low-risk, high-reward” and “high-risk, high-reward” categories for consumption dependent on locations of the catch. Our results are limited and are not intended as consumption advisories but serve to illustrate the need for making more nuanced, geo-specific, consumption guidance for spiny dogfish that is inclusive of seafood traceability and nutritional benefits.
Mostrar más [+] Menos [-]Marine protected area design patterns in the Mediterranean Sea: Implications for conservation
2016
Rodríguez-Rodríguez, D. | Rodríguez, J. | Blanco, J.M. | Abdul Malak, D.
Mediterranean marine protected area (MPA) design patterns regarding geographic distribution, size, spacing and shape were analysed as a proxy of the region's MPA's ecological effectiveness and a first step towards an ecologically coherent MPA network.Results for legally designated MPAs and ecologically functional MPAs accounting for overlaps are presented. Geographically, Mediterranean MPA area is very unevenly distributed, with four-fifths concentrated in just three countries of the north-western part of the basin. Average distance between functional MPAs lies within recommended ecological thresholds, which suggests adequate potential connectivity of the Mediterranean MPA system. Mediterranean designated MPAs are larger than MPAs worldwide on average, although they are generally smaller than international guidance suggests at different levels: ecoregion, country and designation category. On average, Mediterranean designated and functional MPAs have relatively high compactness, which makes them prone to spillover and adequate viability, and less vulnerable to edge effects.
Mostrar más [+] Menos [-]Spatial variability and response to anthropogenic pressures of assemblages dominated by a habitat forming seaweed sensitive to pollution (northern coast of Alboran Sea)
2016
Bermejo, Ricardo | de la Fuente, Gina | Ramírez-Romero, Eduardo | Vergara, Juan J. | Hernández, Ignacio
The Cystoseira ericaefolia group is conformed by three species: C. tamariscifolia, C. mediterranea and C. amentacea. These species are among the most important habitat forming species of the upper sublittoral rocky shores of the Mediterranean Sea and adjacent Atlantic coast. This species group is sensitive to human pressures and therefore is currently suffering important losses. This study aimed to assess the influence of anthropogenic pressures, oceanographic conditions and local spatial variability in assemblages dominated by C. ericaefolia in the Alboran Sea. The results showed the absence of significant effects of anthropogenic pressures or its interactions with environmental conditions in the Cystoseira assemblages. This fact was attributed to the high spatial variability, which is most probably masking the impact of anthropogenic pressures. The results also showed that most of the variability occurred on at local levels. A relevant spatial variability was observed at regional level, suggesting a key role of oceanographic features in these assemblages.
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