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Elemental composition and source identification of very fine aerosol particles in a European air pollution hot-spot 全文
2016
Pokorná, Petra | Hovorka, Jan | Hopke, Philip K.
Positive Matrix Factorization (PMF) was used to identify sources of PM0.09–0.26, very fine aerosol particles, in a residential district of Ostrava Radvanice and Bartovice, a European air pollution hot-spot. Two-hours resolved elemental composition of very fine particulate matter samples were collected by the eighth stage of Davis Rotating-drum Universal-size-cut Monitoring (DRUM) impactor for the campaign period of the 26th January to the 21st February 2012. The campaign consists of smog (26.1–14.2) and post-smog (15–21.2) periods defined by their PM1 concentrations. Three factors were resolved by PMF: coal combustion, raw iron production and steel production. Coal combustion, associated with high concentrations of Se, Br, Pb, K, and As, dominated during the whole period. The contribution of raw iron production, a factor with high concentration of Mn, Fe, Co and Cr, increased significantly when ambient air temperature and the wind direction changed from NE to SW. Alternatively, the contributions of steel production, associated with Cl, K and Zn, were high under NE winds and decreased during the post-smog period. The mass of very fine particles correlated well with CO concentrations (smog r2 = 0.86, post-smog r2 = 0.43), which may indicate an industrial plume. The low value of S/Se (1448) suggests the impact of local/city-wide stationary coal combustion sources located to the N–NE of the monitoring site.
显示更多 [+] 显示较少 [-]Plastic litter in sediments from a marine area likely to become protected (Aeolian Archipelago's islands, Tyrrhenian sea) 全文
2016
Fastelli, Paolo | Blašković, Andrea | Bernardi, Giulia | Romeo, Teresa | Čižmek, Hrvoje | Andaloro, Franco | Russo, Giovanni F. | Guerranti, Cristiana | Renzi, Monia
This research aims to define for the first time levels and patterns of different litter groups (macro, meso and microplastics) in sediments from a marine area designed for the institution of a new marine protected area (Aeolian Archipelago, Italy). Microplastics resulted the principal group and found in all samples analyzed, with shape and colours variable between different sampling sites. MPs levels measured in this study are similar to values recorded in harbour sites and lower than reported in Adriatic Sea, while macroplastics levels are notably lower than in harbor sites. Sediment grain-size and island extent resulted not significant in determining levels and distribution of plastic debris among islands. In the future, following the establishment of the MPA in the study area, these basic data will be useful to check for potential protective effects on the levels and distribution of plastic debris.
显示更多 [+] 显示较少 [-]Are greenhouse gas emissions from international shipping a type of marine pollution? 全文
2016
Shi, Yubing
Whether greenhouse gas emissions from international shipping are a type of marine pollution is a controversial issue and is currently open to debate. This article examines the current treaty definitions of marine pollution, and applies them to greenhouse gas emissions from ships. Based on the legal analysis of treaty definitions and relevant international and national regulation on this issue, this article asserts that greenhouse gas emissions from international shipping are a type of ‘conditional’ marine pollution.
显示更多 [+] 显示较少 [-]Assessment of the environmental quality of coastal sediments by using a combination of in vitro bioassays 全文
2016
Pérez-Albaladejo, Elisabet | Rizzi, Juliane | Fernandes, Denise | Lille-Langøy, Roger | Karlsen, Odd André | Goksøyr, Anders | Oros, Andra | Spagnoli, Federico | Porte, Cinta
The environmental quality of marine sediments collected in the area of influence of the Po and Danube Rivers was assessed by using a battery of bioassays based on the use of PLHC-1 cells, zebrafish-Pxr-transfected COS-7 cells, and sea bass ovarian subcellular fractions. This allowed the determination of multiple endpoints, namely, cytotoxicity, oxidative stress, induction of CYP1A, activation of zebrafish Pxr and inhibition of ovarian aromatase. Organic extracts of sediments influenced by the Danube River and collected near harbors and urban discharges showed significant cytotoxicity, CYP1A induction and inhibition of aromatase activity. An analogous response of CYP1A induction and zfPxr activation was observed, which suggests the existence of common ligands of AhR and PXR in the sediment extracts. The study highlights the usefulness of the selected bioassays to identify those sediments that could pose a risk to aquatic organisms and that require further action in order to improve their environmental quality.
显示更多 [+] 显示较少 [-]Contaminant (PAHs, OCs, PCBs and trace metals) concentrations are declining in axial tissue of sand flathead (Platycephalus bassensis) collected from an urbanised catchment (Port Phillip Bay, Australia) 全文
2016
Gagnon, Marthe Monique | Baker, Jarrad Kyle | Long, Sara M. | Hassell, Kathryn L. | Pettigrove, Vincent J.
Concentrations of PAHs, OCs, PCBs and trace metals were determined in the white muscle of sand flathead Platycephalus bassensis collected at 6 locations in Port Phillip Bay during 2015. No PAHs, OCs or PCBs were detected in the white muscle of sand flathead at any of the locations, however measurable levels of As, Cu, Hg, Se and Zn were detected at all sites. Only As and Hg exhibited regional difference in white muscle concentrations, with As present only in a non-toxic organic form and Hg measured at levels that are comparable to levels reported in reference sites in other studies. All contaminants detected in the white muscle of sand flathead collected in Port Phillip Bay in 2015 were below Australian Food Standards guideline values, and by world standards, the Port Phillip Bay sand flathead population is considered minimally contaminated. Furthermore, tissue contaminant concentrations appear to be decreasing over time.
显示更多 [+] 显示较少 [-]Variability in antioxidant/detoxification enzymes of Sinonovacula constricta exposed to benzo[a]pyrene and phenanthrene 全文
2016
Li, Lei | Jiang, Mei | Shen, Xinqiang
The purpose of this study was to investigate the toxic effects induced by benzo[a]pyrene and phenanthrene. For this purpose, a study was performed on the clam exposed to 0.0, 0.5, 4.5μgL−1 B(a)P and PHE for 15days using parameters of antioxidant defenses and oxidative stress. Antioxidant biomarkers including ethoxyresorufin-O-deethylase, glutathione S-transferase, superoxide dismutase, and glutathione and rylhydrocarbon hydroxylasein gills of Sinonovacula constricta, were analyzed after a 1-, 3-, 9- and 15-day exposure to seawater containing B(a)P and PHE. Integrated biomarker response was calculated by combining multiple biomarkers into a single value. The results showed that the activity of all antioxidant biomarkers was induced throughout the exposure period, and different patterns of variations were detected with exposure time. In addition, the study showed that the two concentrations used caused the activation of different general detoxification mechanisms, and the same concentration at different two PAH compounds induced different toxicity responses.
显示更多 [+] 显示较少 [-]The tarballs on Texas beaches following the 2014 Texas City “Y” Spill: Modeling, chemical, and microbiological studies 全文
2016
Bacosa, Hernando P. | Thyng, Kristen M. | Plunkett, Stefanie | Erdner, Deana L. | Liu, Zhanfei
We modeled the transport of oil, source-fingerprinted 44 tarball samples from Galveston Island (GV) and Mustang Island (MT), and determined the hydrocarbon and bacterial community composition of these tarballs following the 2014 Texas City “Y” Oil Spill (TCY). Transport modeling indicated that the tarballs arrived in MT before the samples were collected. Source-fingerprinting confirmed that the tarballs collected from GV and MT, 6d and 11d after the TCY, respectively, originated from the spill. Tarballs from GV showed 21% depletion of alkanes, mainly C9–C17, and 55% depletion of PAHs mainly naphthalenes, and dominated by alkane-degrading Alcanivorax and Psychrobacter. Samples from MT were depleted of 24% alkanes and 63% PAHs, and contained mainly of PAH-degrading Pseudoalteromonas. To the best of our knowledge, this is the first study to relate oil transport, tarball source-fingerprinting, chemistry, and microbiology, which provides insights on the fate of oil in the northern Gulf of Mexico.
显示更多 [+] 显示较少 [-]Master Plan Jakarta, Indonesia: The Giant Seawall and the need for structural treatment of municipal waste water 全文
2016
van der Wulp, Simon A. | Dsikowitzky, Larissa | Hesse, Karl Jürgen | Schwarzbauer, Jan
In order to take actions against the annual flooding in Jakarta, the construction of a Giant Seawall has been proposed in the Master Plan for National Capital Integrated Coastal Development. The seawall provides a combination of technical solutions against flooding, but these will heavily modify the mass transports in the near-coastal area of Jakarta Bay. This study presents numerical simulations of river flux of total nitrogen and N,N-diethyl-m-toluamide, a molecular tracer for municipal waste water for similar scenarios as described in the Master Plan. Model results demonstrate a strong accumulation of municipal wastes and nutrients in the planned reservoirs to extremely high levels which will result in drastic adverse eutrophication effects if the treatment of municipal waste water is not dealt with in the same priority as the construction of the Giant Seawall.
显示更多 [+] 显示较少 [-]Molecular biodiversity of Red Sea demosponges 全文
2016
Erpenbeck, Dirk | Voigt, Oliver | Al-Aidaroos, Ali M. | Berumen, Michael L. | Büttner, Gabriele | Catania, Daniela | Guirguis, Adel Naguib | Paulay, Gustav | Schätzle, Simone | Wörheide, Gert
Sponges are important constituents of coral reef ecosystems, including those around the Arabian Peninsula. Despite their importance, our knowledge on demosponge diversity in this area is insufficient to recognize, for example, faunal changes caused by anthropogenic disturbances. We here report the first assessment of demosponge molecular biodiversity from Arabia, with focus on the Saudi Arabian Red Sea, based on mitochondrial and nuclear ribosomal molecular markers gathered in the framework of the Sponge Barcoding Project. We use a rapid molecular screening approach on Arabian demosponge collections and analyze results in comparison against published material in terms of biodiversity. We use a variable region of 28S rDNA, applied for the first time in the assessment of demosponge molecular diversity. Our data constitutes a solid foundation for a future more comprehensive understanding of sponge biodiversity of the Red Sea and adjacent waters.
显示更多 [+] 显示较少 [-]Esterase activity (EA), total oxidant status (TOS) and total antioxidant capacity (TAC) in gills of Mytilus galloprovincialis exposed to pollutants: Analytical validation and effects evaluation by single and mixed heavy metal exposure 全文
2016
Franco Vidal, Lorena | Romero, Diego | García-Navarro, José A. | Teles, Mariana | Tvarijonaviciute, Asta
The aims of the present study were to optimize and validate methods for esterase activity (EA), total oxidant status (TOS) and total antioxidant capacity (TAC) determination in mussel' gills, and to establish the relationships between these biomarkers and Pb, Cd and Cu pollution, in single form and ternary mixture. Two different buffers for sample homogenization, the need of ultracentrifugation, and analytical validation were evaluated. Coefficients of variation, when buffer without additives and ultracentrifugation were used, were <15%, and recovery were 97%–109% in all cases. The EA response tends to decrease with treatments, TOS decreased significantly in Cd and ternary groups, while TAC tended to increase in treatments with Pb, Cd and ternary groups. In conclusion, the methods for EA, TOS and TAC measurements in gills of mussel were precise and accurate and could be interesting resources in biomonitoring programmes.
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