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Occurrence of alkylphenols and alkylphenol ethoxylates in North Sea sediment samples collected across oil and gas fields Texte intégral
2022
McLaren, Diana E.K. | Rawlins, Andrew J.
Alkylphenol ethoxylates (APEs) have been used in several offshore oil and gas production applications including as emulsifiers in drilling mud formulations, which may have resulted in their disposal to sea. Despite concern over the endocrine disrupting potential of their alkylphenol (AP) degradation products, information on the presence of AP/APEs in marine sediments in the vicinity of oil and gas production facilities is scarce. This paper presents the occurrence of AP/APEs in marine sediment in North Sea oil and gas fields. The concentrations of octylphenol, nonylphenol and their ethoxylates near offshore installations were broadly comparable to, or higher than those of coastal and estuarine point source discharges. When compared to environmental assessment criteria, the NPCA Class V threshold values for octylphenol and nonylphenol were exceeded within 100 m and 500 m of infrastructure respectively, with higher concentrations of AP/APEs reported in fields that came online prior to 1986.
Afficher plus [+] Moins [-]Quantitative assessment of two oil-in-ice surface drift algorithms Texte intégral
2022
de Aguiar, Victor | Dagestad, Knut-Frode | Hole, Lars Robert | Barthel, Knut
Quantitative assessment of two oil-in-ice surface drift algorithms Texte intégral
2022
de Aguiar, Victor | Dagestad, Knut-Frode | Hole, Lars Robert | Barthel, Knut
The ongoing reduction in extent and thickness of sea ice in the Arctic might result in an increase of oil spill risk due to the expansion of shipping activity and oil exploration shift towards higher latitudes. This work assessed the response of two oil-in-ice surface drift models implemented in an open-source Lagrangian framework. By considering two numerical modeling experiments, our main finding indicates that the drift models provide fairly similar outputs when forced by the same input. It was also found that using higher resolution ice-ocean model does not imply better results. We highlight the role of sea ice in the spread, direction and distance traveled by the oil. The skill metric seems to be sensitive to the drift location, and drift model re-initialization is required to avoid forecast deterioration and ensure the accurate tracking of oil slicks in real operations.
Afficher plus [+] Moins [-]Quantitative assessment of two oil-in-ice surface drift algorithms Texte intégral
2022
Martins de Aguiar, Victor Cesar | Dagestad, Knut-Frode | Hole, Lars Robert | Barthel, Knut Sven
The ongoing reduction in extent and thickness of sea ice in the Arctic might result in an increase of oil spill risk due to the expansion of shipping activity and oil exploration shift towards higher latitudes. This work assessed the response of two oil-in-ice surface drift models implemented in an open-source Lagrangian framework. By considering two numerical modeling experiments, our main finding indicates that the drift models provide fairly similar outputs when forced by the same input. It was also found that using higher resolution ice-ocean model does not imply better results. We highlight the role of sea ice in the spread, direction and distance traveled by the oil. The skill metric seems to be sensitive to the drift location, and drift model re-initialization is required to avoid forecast deterioration and ensure the accurate tracking of oil slicks in real operations. | publishedVersion
Afficher plus [+] Moins [-]Non-destructive biomarkers can reveal effects of the association of microplastics and pharmaceuticals or personal care products Texte intégral
2022
da Silva, Letícia Fernanda | Nobre, Caio Rodrigues | Moreno, Beatriz Barbosa | Pereira, Camilo Dias Seabra | de Souza Abessa, Denis Moledo | Choueri, Rodrigo Brasil | Gusso-Choueri, Paloma Kachel | Cesar, Augusto
Methods to assess the effects of contaminants on marine organisms typically involve euthanasia to obtain samples, but less invasive techniques may be more appropriate for working with threatened species. In this study, were assessed the biological responses of crabs exposed to microplastics and contaminants of emerging concern. Biochemical and cellular effects (lipid peroxidation, DNA damage, cholinesterase activity, and lysosomal membrane stability) in hemolymph were analyzed in a kinetic study, at 3 and 7 days, in U. cordatus exposed to microplastics spiked with Triclosan (TCS) or 17α-Ethynylestradiol (EE2). The results showed that the contaminants were produced toxic effects in the crabs exposed either to the microplastics alone (oxidative stress, genotoxicity, and neurotoxicity), or to microplastics with TCS or EE2 adsorbed (neurotoxic and cytotoxic). The present study showed the responsiveness of non-lethal analyzes to understanding the biological effects of combined exposure to microplastics and chemical pollution.
Afficher plus [+] Moins [-]Scenery evaluation as a tool for the determination of visual pollution in coastal environments: The Rabigh coastline, Kingdom of Saudi Arabia as a study case Texte intégral
2022
Alharbi, Omar A. | Rangel-Buitrago, Nelson
Visual pollution is the visible deterioration and negative aesthetic quality of the landscape. Erosion, marine wrack, litter, sewage, and beach driving are affecting the coastal scenery and are generating a visual pollution problem on the Rabigh coastal area, Kingdom of Saudi Arabia. This work provides the scenic evaluation of 31 coastal sites using the Coastal Scenery Evaluation System (CSES) to determine the current state of this situation and give management inputs. The CSES assesses values from a checklist of 18 physical and 8 human parameters and allows the calculation of a scenic evaluation index (D Value), which classifies coastal sites into five classes: Class I, usually natural areas of top scenic characteristics, to Class V, poor scenic natural areas with a higher impact of human interventions. Along the study area, three sites (9.7 %) appeared in Class II; five (16.1 %) in Class III; 15 (48.4 %) in Class IV, and eight sites (25.8 %) in Class V. Class I sites were not found in the study area. Assessment presented in this work provides a complete overview of the Rabigh coastal scenery and serves as a baseline for implementing management strategies to cope the visual pollution problem.
Afficher plus [+] Moins [-]Comparative multi-species analysis of potassium cyanide toxicity Texte intégral
2022
Tez, Serkan | Oral, Rahime | Koçbaş, Fatma | Koru, Edis | Türkçü, Neslihan | Pagano, Giovanni | Trifuoggi, Marco
Potassium cyanide (KCN), a highly water soluble and bioaccumulative cyanide salt, is examined to determine the toxic effects by using two green algae (Dunaliella viridis, Nannochloropsis oculata) and genetically different two sea urchin (Paracentrotus lividus, Arbacia lixula) species. To determine the toxic effects on the early developmental stages of sea urchin embryos, 72-hour embryotoxicity studies were conducted. Potassium cyanide toxicity at cellular level was also investigated and 6-hour embryos of both sea urchin species were used to determine genotoxic effects of KCN. Since plutei naturally feed on microalgae, two species of plankton were used to reveal phytotoxic effects of KCN. KCN was found to be embryo- geno- and phytotoxic. EC₅₀'s for P. lividus and A. lixula were found 7.96 and 6.52 μM. IC₅₀'s for N. oculata for 48 h and 72 h were found 23.66 and 80.45 μM. IC₅₀'s for D. viridis for 48 h and 72 h were found 14.31 and 23.36 μM.
Afficher plus [+] Moins [-]Fatty acid-based index development in estuarine organisms to pinpoint environmental contamination Texte intégral
2022
Fonseca, Vanessa F. | Duarte, Irina A. | Feijão, Eduardo | Matos, Ana Rita | Duarte, Bernardo
Estuaries have long been preferred areas of human settlement, where multiple anthropogenic activities take place, which have contributed to a significant decrease in environmental quality of these ecosystems. Accordingly, environmental monitoring and management have long relied on the development of tools that summarize and simplify complex information and provide direct interpretation of quality status. Here, the fatty acid profiles of three abundant estuarine species, namely Hediste diversicolor, Carcinus maenas and Pomatoschistus microps, were used to develop and validate a multimetric index, based on the Euclidean dissimilarities of profiles between sites, in response to contamination gradient in a large urban estuary. Spatial differences were generally related to unsaturated fatty acids (mono- and polyunsaturated, of the n−3 and n−6 series) in all species, albeit more pronounced in P. microps. Multivariate models returned high classification accuracies for the three sampled sites, varying from 73.3% in the invertebrate species to 100.0% in the fish species. Results show the applicability of the developed FA-based index, particularly due to the easy of communication, for managers and the public alike, but also highlight the need for prior validation on species suitability or sensitivity to depict environmental contamination.
Afficher plus [+] Moins [-]The application of the DAPSI(W)R(M) framework to the plastic pellets chain Texte intégral
2022
Izar, G.M. | Choueri, R.B. | Martinez, S.T. | da Rocha, G.O. | Albergaria-Barbosa, A.C.R.
Single-use plastic, few global engagement and lack of policies contribute to the global challenge about plastic marine litter. This form of contamination can cause injury and death of marine wildlife. Microplastics (>5 mm) represent an important fraction of plastic litter. They include the plastic pellets that are used as raw material within plastic industry that can be unintentionally spilled into the environment during the industrial processes. In an initiative in order to facilitate the understanding and communication of plastic pellets as a social and environmental problem, we applied the Drivers-Activities-Pressures-State changes-Impacts (on Welfare)-Responses (as Measures) (DAPSI[W]R[M]) framework to plastic pellets chain. We also analyzed possible mitigating measures and their actions along the plastic pellets chain. This DAPSI(W)R(M) framework aim to show an overview of the plastic pellets chain and solutions for politicians and decision makers to help solve this socio-environmental problem that needs the engagement of all stakeholders involved.
Afficher plus [+] Moins [-]Quantifying spatial variation in the uptake of microplastic by mussels using biodeposit traps: A field-based study Texte intégral
2022
Piarulli, Stefania | Scapinello, Sara | Sciutto, Giorgia | Prati, Silvia | Mazzeo, Rocco | Booth, Andy M. | Airoldi, Laura
Quantifying spatial variation in the uptake of microplastic by mussels using biodeposit traps: A field-based study Texte intégral
2022
Piarulli, Stefania | Scapinello, Sara | Sciutto, Giorgia | Prati, Silvia | Mazzeo, Rocco | Booth, Andy M. | Airoldi, Laura
Spatial uptake patterns of microplastics (MP) by marine species are largely unexplored under field conditions. A novel “biodeposit trap” that measure uptake and egestion of MP by suspension-feeders through the analysis of their biodeposits, was designed and used to estimate the spatial variation of these processes by mussels in field conditions. Traps containing wild or farmed mussels or control empty shells were deployed at three sites characterised by different MP concentrations and water flow conditions. A different MP dimensional composition was observed between MP pools present in biodeposit and control traps, with the latter shifted towards higher dimensional range (0.05–5 mm). Conversely, mussels accumulated small MP (0.02–0.05 mm) into their biodeposits without any significant difference between wild and farmed specimens. MP uptake rates were on average 4–5 times higher at the site where MP contamination was expected to be highest and where water flow conditions were considered moderate.
Afficher plus [+] Moins [-]Quantifying spatial variation in the uptake of microplastic by mussels using biodeposit traps: A field-based study Texte intégral
2022
Piarulli, Stefania | Scapinello, Sara | Sciutto, Giorgia | Prati, Silvia | Mazzeo, Rocco | Booth, Andrew | Airoldi, Laura
Spatial uptake patterns of microplastics (MP) by marine species are largely unexplored under field conditions. A novel “biodeposit trap” that measure uptake and egestion of MP by suspension-feeders through the analysis of their biodeposits, was designed and used to estimate the spatial variation of these processes by mussels in field conditions. Traps containing wild or farmed mussels or control empty shells were deployed at three sites characterised by different MP concentrations and water flow conditions. A different MP dimensional composition was observed between MP pools present in biodeposit and control traps, with the latter shifted towards higher dimensional range (0.05–5 mm). Conversely, mussels accumulated small MP (0.02–0.05 mm) into their biodeposits without any significant difference between wild and farmed specimens. MP uptake rates were on average 4–5 times higher at the site where MP contamination was expected to be highest and where water flow conditions were considered moderate. | publishedVersion
Afficher plus [+] Moins [-]Ecological risks of heavy metals on surficial sediment of Nijhum Dweep (Island), an important biodiversity area of Bangladesh Texte intégral
2022
Rahman, Mahfuzur | Saima, Jerin | Rima, Sabrina Akhter | Hossain, Md Imam Sohel | Das, Delip K. | Bakar, Muhammad Abu | Siddique, Mohammad Abdul Momin
Ten surficial sediment samples (up to a depth of 3 cm) were randomly collected during the pre-monsoon and analyzed for nine heavy metals using an atomic absorption spectrophotometer (AAS) to assess the distribution, contamination levels, and potential sources of heavy metals. The particle size distribution of the sediments was also investigated using a laser particle size analyzer. The mean concentration (mg/kg) of the analyzed metals followed a decreasing order of Fe (4706.24) > Mn (95.20) > Cu (36.97) > Zn (20.65) > Ni (9.26) > Cr (7.20) > Pb (5.63) > Co (5.52) > Cd (0.29). Surficial sediment of the Island was low to moderately contaminated by Cd and, to a laser extent by Cu in terms of enrichment factor (EF), geo-accumulation index (Igeo), and contamination factor. Ecologically, the Nijhum Dweep area was at low to moderate risk, where Cd was the most potential ecological risk factor. The Pearson correlation analysis revealed a significant positive correlation among Cr, Pb, Zn, Mn, Cd, Fe, Co, Ni, and silt particles, whereas a negative correlation with sand particles. No correlation was found with Cu and other metals except clay particles.
Afficher plus [+] Moins [-]Chemical composition and morphology of the Mediterranean mussel, Black Sea coast of Russia Texte intégral
2022
Zakharikhina, Lalita | Rudev, Peter | Paltseva, Anna
Mussels, whose soft tissues are used in food and are rich in high-quality protein, are essential in marine fisheries. Mediterranean mussels (Mytilus galloprovincialis Lam) used to assesses the pollution level of a coastal marine zone due to exposure to local technological processes populate the metal piles of a pier built for the 2014 Olympics in Sochi Olympic Park. The chemical composition of mussel soft tissues (61 elements analyzed by the ICP method) indicates anthropogenic pollution of the coastal zone ecosystem, most pronounced in the 50-m zone along the coast due to run off from the terrestrial ecosystem affected by the Olympic construction. Line measurements of annual rings of 6-year-old individuals of mussels showed stabilization of the ecological situation in the coastal-marine zone by 2019. This study can be used for comprehensive ecological monitoring of coastal-marine zones with similar conditions and anthropogenic load.
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