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Synthetic lipids as a biocide candidate for disinfection of ballast water Texto completo
2018
Batista, William R. | Fernandes, Flavio C. | Neves, Maria H.C.B. | Nascimento, Thiana S. | Lopes, Rosangela S.C. | Lopes, Claudio C. | Ziegler, Gregory P. | Soler-Figueroa, Brenda M. | Sparks, Darrick | Fontaine, Diana N. | Carney, Katharine J. | Quiñones-Oquendo, Luz E. | Ruiz, Gregory M.
The objective of this study is to propose the use of specific synthetic lipid as an active substance (biocide) in the control of harmful aquatic microorganisms, such as pathogens and non-indigenous species, transported in ships' ballast water. The biocide candidate, without metal or halogen components, was produced from a sub-product of the edible oil industry, the lecithin. Laboratory assays were conducted with phytoplankton, zooplankton, and marine bacteria to evaluate the efficiency of the biocide. The study also considers specific biocide's characteristics related to environmental risks, such as chemical composition, persistence, bioaccumulation, and toxicity. Results showed that, in the first 24 h of treatment, the biocide effectively reduced the concentration of the planktonic micro-organisms to very low levels. Additionally, a preliminary risk evaluation pointed that biocide candidate has a low residual toxicity, also a low potential for persistence and bioaccumulation in the environment.
Mostrar más [+] Menos [-]Changes to polychlorinated biphenyl (PCB) signatures and enantiomer fractions across different tissue types in Guillemots Texto completo
2018
Megson, David | Brown, Thomas A. | O'Sullivan, Gwen | Robson, Matthew | Ortiz, Xavier | Worsfold, Paul J. | Comber, Sean | Lohan, Maeve C. | Reiner, Eric J.
Two Guillemot carcases were dissected, each providing 12 discrete tissue samples and 3 samples of partially digested food. One hundred and five PCBs from the 209 PCBs determined by GCxGC-ToFMS were detected. The relative proportions of individual PCBs did not vary greatly within tissue types, although the PCB profile from undigested food could be distinguished. Enantiomer fractions (EFs) were determined for CB-95, CB-136 and CB-149 by GC-HRqToFMS. EFs in the partially digested food were near racemic, with high levels of enrichment for E1 CB-95 in the kidneys and liver (EF of 0.80 and 0.84 respectively). This provides some of the clearest evidence to date that fractionation takes place in the organs where metabolic biotransformation and elimination of PCBs occurs. Our findings also confirm the ability of non-lethal sampling techniques, such as collection of small (<1 g) blood samples, to provide PCB signatures that are representative of an individual organism.
Mostrar más [+] Menos [-]Evaluating the impact of sewage discharges on the marine environment with a lightweight AUV Texto completo
2018
Bonin-Font, Francisco | Lalucat, Jordi | Oliver-Codina, Gabriel | Massot-Campos, Miquel | Font, Eric Guerrero | Carrasco, Pep Lluis Negre
Environmental studies that use small Autonomous Underwater Vehicles (AUVs) can survey wider and deeper areas, compared to traditional methods, at a reasonable cost. Thanks to the precise vehicle navigation systems, the data collected can be accurately geolocalized. Besides, lightweight vehicles can be deployed from the shore or from small boats and programmed by means of user-friendly graphical interfaces, thus reducing and simplifying the need of human resources and infrastructures. Based on such a technology, this paper presents a framework to assess the environmental impact of a marine sewage outfall set in the Bay of Palma (Mallorca, Spain). We report the results of the analysis of the images recorded in the course of six missions conducted with an AUV. The plan was designed after a microbiological analysis detected the presence of cyanobacteria in a sample of sand and water collected by scuba divers close to the sewer pipe mouth.
Mostrar más [+] Menos [-]Degradation of Deepwater Horizon oil buried in a Florida beach influenced by tidal pumping Texto completo
2018
Huettel, Markus | Overholt, Will A. | Kostka, Joel E. | Hagan, Christopher | Kaba, John | Wells, Wm Brian | Dudley, Stacia
After Deepwater Horizon oil reached the Florida coast, oil was buried in Pensacola Beach (PB) sands to ~70cm depth, resulting in Total Petroleum Hydrocarbon (TPH) concentrations up to ~2kg per meter of beach. This study followed the decomposition of the buried oil and the factors influencing its degradation. The abundance of bacteria in oiled sand increased by 2 orders of magnitude within one week after oil burial, while diversity decreased by ~50%. Half-lives of aliphatic and aromatic hydrocarbons reached 25 and 22days, respectively. Aerobic microbial oil decomposition, promoted by tidal pumping, and human cleaning activities effectively removed oil from the beach. After one year, concentrations of GC-amenable hydrocarbons at PB were similar to those in the uncontaminated reference beach at St. George Island/FL, and microbial populations that disappeared after the oil contamination had reestablished. Yet, oxihydrocarbons can be found at PB to the present day.
Mostrar más [+] Menos [-]Inorganic arsenic causes apoptosis cell death and immunotoxicity on European sea bass (Dicentrarchus labrax) Texto completo
2018
Cordero, Hector | Morcillo, Patricia | Martínez, Salvadora | Meseguer, José | Pérez-Sirvent, Carmen | Chaves-Pozo, Elena | Martínez Sánchez, María José | Cuesta Arranz, Alberto | Ángeles Esteban, M.
Inorganic arsenic causes apoptosis cell death and immunotoxicity on European sea bass (Dicentrarchus labrax) Texto completo
2018
Cordero, Hector | Morcillo, Patricia | Martínez, Salvadora | Meseguer, José | Pérez-Sirvent, Carmen | Chaves-Pozo, Elena | Martínez Sánchez, María José | Cuesta Arranz, Alberto | Ángeles Esteban, M.
Inorganic arsenic (As) is one of the most toxic pollutants in the water. We have studied their effects on the marine teleost European sea bass (Dicentrarchus labrax) at 2 and 10 days of 5 μM of As2O3 (sub-lethal doses) waterborne exposure. Arsenic accumulates in liver and gill tissues. The expression profile of five genes (bax, blc2, casp3, casp8 and casp9) involved in apoptosis cell death confirmed apoptotic effects in liver, slight changes in gill and no effects in skin according with the histopathology findings. Total IgM level and peroxidase activities were increased at 2 and 10 days, respectively. The bactericidal activity was decreased at 2 days after As exposure. A general decrease of cellular immune activities with significant differences in the case of respiratory burst activity was observed after 2 and 10 days of exposure. This work describes for the first time the effects of As exposure on European sea bass.
Mostrar más [+] Menos [-]Inorganic arsenic causes apoptosis cell death and immunotoxicity on European sea bass (Dicentrarchus labrax) Texto completo
2018
Cordero, Héctor | Morcillo, Patricia | Martínez, Salvadora | Meseguer, José | Pérez-Sirvent, Carmen | Chaves-Pozo, Elena | Martínez-Sánchez, María José | Cuesta, Alberto | Esteban, María Ángeles
Inorganic arsenic (As) is one of the most toxic pollutants in the water. We have studied their effects on the marine teleost European sea bass (Dicentrarchus labrax) at 2 and 10 days of 5 μMofAs2O3 (sub-lethal doses) waterborne exposure. Arsenic accumulates in liver and gill tissues. The expression profile of five genes (bax, blc2, casp3, casp8 and casp9) involved in apoptosis cell death confirmed apoptotic effects in liver, slight changes in gill and no effects in skin according with the histopathology findings. Total IgM level and peroxidase activities were increased at 2 and 10 days, respectively. The bactericidal activity was decreased at 2 days after As exposure. A general decrease of cellular immune activities with significant differences in the case of respiratory burst activity was observed after 2 and 10 days of exposure. This work describes for the first time the effects of As exposure on European sea bass. | SI
Mostrar más [+] Menos [-]Spreading of waxy oils on calm water Texto completo
2018
Brönner, Ute | Johansen, Øistein | Leirvik, Frode | Nordam, Tor | Sørheim, Kristin R.
Spreading of waxy oils on calm water Texto completo
2018
Brönner, Ute | Johansen, Øistein | Leirvik, Frode | Nordam, Tor | Sørheim, Kristin R.
The objective of this paper is to provide a simple extension of the much-used gravity spreading model for oil on calm water to account for the spreading behavior of waxy crude oils in cold waters – including the observed retardation and eventual termination of spreading at certain oil film thicknesses. This peculiar behavior is not predicted by traditional spreading models for oil on calm water (i.e. viscous-gravity spreading models), but may occur due to non-Newtonian oil properties caused by precipitation of wax at low temperatures. To clarify the spreading behavior of such oils, SINTEF has conducted a series of laboratory experiments with a range of waxy oil mixtures. The present paper contains analyses of data from these experiments, including favorable comparisons with calculations by a proposed improved surface spreading model.
Mostrar más [+] Menos [-]Spreading of waxy Crude Oils on calm weather | Spreading of waxy Crude Oils on calm weather Texto completo
2018
Brönner, Ute | Johansen, Øistein | Leirvik, Frode | Nordam, Tor | Sørheim, Kristin Rist
The objective of this paper is to provide a simple extension of the much-used gravity spreading model for oil on calm water to account for the spreading behavior of waxy crude oils in cold waters – including the observed retardation and eventual termination of spreading at certain oil film thicknesses. This peculiar behavior is not predicted by traditional spreading models for oil on calm water (i.e. viscous-gravity spreading models), but may occur due to non-Newtonian oil properties caused by precipitation of wax at low temperatures. To clarify the spreading behavior of such oils, SINTEF has conducted a series of laboratory experiments with a range of waxy oil mixtures. The present paper contains analyses of data from these experiments, including favorable comparisons with calculations by a proposed improved surface spreading model. | Spreading of waxy Crude Oils on calm weather | acceptedVersion
Mostrar más [+] Menos [-]Arsenic and five metal concentrations in the muscle tissue of bigeye tuna (Thunnus obesus) in the Atlantic and Indian Oceans Texto completo
2018
Chen, Zhengyou | Chen, Y. T. | Cheng, Jingsun | Hsu, C.-C. | Liu, L.-L. | Chen, H.-S. | Chen, M.-H.
White muscle concentrations of As, Cd, Cu, Fe, Se, and Zn were investigated in Atlantic- and Indian-bigeye tuna (BET) (Thunnus obesus) from 6 regions. As and Cd muscle concentrations were significantly higher in the Indian-BET than in the Atlantic-BET, whereas the Indian-BET caught in the waters off South Africa revealed the highest As, Se, and Zn muscle concentrations. Accordingly, multidimensional scaling separated them into two oceanic groups. Positive linear relationships between muscle Cd concentration and fork length (FL) were established in both oceans. For the other elements, only muscle-Fe and FL relationship was found in the Atlantic-BET. 10.3% of BET > 145 cm FL from both oceans possessed muscle Cd concentrations exceeding the food safety limit (0.1 μg g−1 wet weight) set by the European Commission. Increased Cd, Cu and Zn pollution was found in the Atlantic Ocean compared with previous data, with higher levels found in the Indian Ocean.
Mostrar más [+] Menos [-]Loricate ciliates as an indicator of eutrophication status in the estuarine and coastal waters Texto completo
2018
Sivasankar, R. | Ezhilarasan, P. | Sathish Kumar, P. | Naidu, S.A. | Rao, G.D. | Kanuri, Vishnu Vardhan | Ranga Rao, V. | Ramu, K.
Owing to the environmental sensitivity of ciliate species, the monitoring and assessment of these communities can indicate the health of the aquatic environment. Sampling for loricate ciliates was carried out during different seasons at three different locations in the estuarine and coastal waters of Kochi, Southwest coast of India. The loricate ciliate community comprising of 27 species belonging to 10 genera revealed significant differences among the three sampling locations. The maximum numerical abundance and less species diversity of loricate ciliates were recorded at the estuarine locations whereas the minimum abundance and more species diversity were encountered in the coastal waters. Multivariate statistical analyses revealed that Tintinnopsis beroidea and Tintinnopsis uruguayensis were correlated positively with nutrients in the estuarine environment, which receives large amount of anthropogenic inputs. Thus, we propose that these two loricate ciliates may be considered as a potential bioindicator of eutrophication status in marine ecosystems.
Mostrar más [+] Menos [-]First report of occurrence, distribution, and composition of microplastics in surface waters of the Sea of Marmara, Turkey Texto completo
2018
Plastic is produced today in large quantities and used for many purposes. At the end of use, a large part of it gets into the environment, often into the sea and there it is fragmented into the smallest fragments, so-called microplastic (MP). MPs pose a serious challenge to the marine environment such as the sources and properties of MP particles, their impact on marine organisms, and the challenges of environmental pollution. This work, carried out in the fourteen sites in the area, is the first reference to the detection of MP distribution at surface waters in the Sea of Marmara, Turkey. As a result of this study, the average level of MP in the surface was determined to be 1.263 item/m2. The results were higher compared of the most other adjacent regions and show that the Sea of Marmara started to face that problem.
Mostrar más [+] Menos [-]Spatial and temporal analysis of biliary 1-hydroxypyrene, hepatic ethoxyresorufin-O-deethylase and muscle acetylcholinesterase activity in UK flatfish Texto completo
2018
(Craig D.),
Chemical pollution of the marine environment from anthropogenic sources is a global concern due to the potential for long term effects on the ecosystem. Chemical monitoring schemes can detect harmful substances in water, sediment or biota. However, the presence of specific determinants gives no information on how individual species or the ecosystem are impacted. Biological effects techniques are therefore used in environmental monitoring schemes to provide a clearer picture of whether the chemicals present are causing deleterious effects on the species sampled, or whether organisms have been exposed to certain classes of organic contaminants that they may be able to metabolise. Using these techniques, we can provide an assessment of the health of our marine environment (Thain et al., 2008).
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