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Development of aerosol wind tunnel and its application for evaluating the performance of ambient PM10 inlets Полный текст
2013
Lee, Sangil | Yu, Miae | Kim, Hun H.
Size selective particulate matter (PM) sampling inlets play an important role in ambient PM measurement. Improper design of the sampling inlets results in collecting of PM with undesired size, which leads to significant errors in the measurement of ambient PM concentrations. Therefore, the performance of PM inlets should be carefully evaluated in a proper environment prior to their field of applications. In this study, a new aerosol wind tunnel system was designed to evaluate the performance of ambient PM10 inlets and evaluated for the uniformity of wind speed distribution and aerosol concentration. In addition, a custom–made PM10 inlet was tested in the aerosol wind tunnel to determine its 50% cutoff diameter. Results of the wind speed distributions show that the percentage deviations from the mean wind speeds at any measurement point are less than 10% with turbulence intensity of less than 5% for three different wind speed levels (0.57m/s, 2.22m/s, and 6.67m/s). Results from the aerosol concentration measurements show that the percentage deviations from the mean aerosol concentrations at any measurement point are less than 10% for three different wind speed levels, which meets the aerosol wind tunnel performance specifications specified by the U.S. Environmental Protection Agency (EPA). Results from PM10 inlet performance tests show that the 50% cutoff diameters of the PM10 inlet are 10.0 μm, 10.3 μm, and 10.0 μm at wind speeds of 0.57m/s, 2.22m/s, and 6.67m/s, respectively. The PM10 inlet is characterized to meet the performance specifications for PM10 inlets, 10.0±0.5 µm, specified by the U.S. EPA. The results indicate that the newly developed aerosol wind tunnel meets the performance requirements for evaluating the performance of PM10 size selective inlets.
Показать больше [+] Меньше [-]Chemical characterization and source apportionment of PM10 and PM2.5 in the metropolitan area of Costa Rica, Central America Полный текст
2013
Murillo, Jorge Herrera | Roman, Susana Rodriguez | Rojas Marin, Jose Felix | Ramos, Arturo Campos | Jimenez, Salvador Blanco | Cárdenas González, Beatriz | Baumgardner, Darrel Gibson
PM10 and PM2.5 levels, concentrations of major ionic components, trace elements, and organic and elemental carbon were evaluated from samples collected in 4 sites (industrial, commercial and residential zones) located in the metropolitan area of Costa Rica. The annual mean PM levels were higher in high traffic–commercial (HE–01) and industrial (BE–02) sites, 55 μg m–3 and 52 μg m–3 for PM10 and 37 μg m–3 and 36 μg m–3 for PM2 5, respectively. The major components of PM25 were organic matter (OM) and elemental carbon (EC) (44.5–69.9%), and secondary ions (16.1–27.2%), whereas the major components of PM10 were OM+EC (32.7–59.4%), crustal material (23.5–35.6%) and secondary ions (11.4–26.9%). For the most of the sampling sites, PM10 and PM2.5 concentrations were lower during the dry season and increased gradually in the rainy season due to wind patterns. PMF model identified 8 principle sources for PM10 and PM2.5 in the industrial site (crustal, secondary sulfate, secondary nitrate, secondary organic, traffic, sea–salt aerosols, industrial and oil combustion), 6 and 5 sources in commercial and residential sites, respectively. The source contributions showed a clear seasonal pattern for all the sites.
Показать больше [+] Меньше [-]Ecotoxicological assessment of sediments from an urban marine protected area (Xixová-Japuí State Park, SP, Brazil) Полный текст
2013
Araujo, G.S. | Moreira, L.B. | Morais, R.D. | Davanso, M.B. | Garcia, T.F. | Cruz, A.C.F. | Abessa, D.M.S.
This study aimed to evaluate the environmental quality of the marine portion of Xixová-Japuí State Park (XJSP), an urban marine protected area, which is influenced by multiple contamination sources, by using ecotoxicological and geochemical analyses. Sediments were predominantly sandy, with low CaCO3 and organic matter contents, and presented contamination by metals (Cd,Cu,Zn). Acute toxicity was detected in three tested samples, and copepod exposed to sediments from four stations exhibited lower fecundities, despite the absence of significant effects. Contamination and toxicity seemed to be associated, suggesting that the environment is degraded and presents risks to the biota. Whole sediment TIE indicated ammonia as a main responsible for toxicity, suggesting sewage is a main contributor to sediment degradation. As external contamination sources seem to be negatively influencing the sediment quality, the park conservation objectives are not being fully reached, demanding actions to mitigate impacts.
Показать больше [+] Меньше [-]Monitoring of a wide range of organic micropollutants on the Portuguese coast using plastic resin pellets Полный текст
2013
Mizukawa, Kaoruko | Takada, Hideshige | Ito, Maki | Geok, Yeo Bee | Hosoda, Junki | Yamashita, Rei | Saha, Mahua | Suzuki, Satoru | Miguez, Carlos | Frias, João | Antunes, Joana Cepeda | Sobral, Paula | Santos, Isabelina | Micaêlo, Cristina | Ferreira, Ana María
Monitoring of a wide range of organic micropollutants on the Portuguese coast using plastic resin pellets Полный текст
2013
Mizukawa, Kaoruko | Takada, Hideshige | Ito, Maki | Geok, Yeo Bee | Hosoda, Junki | Yamashita, Rei | Saha, Mahua | Suzuki, Satoru | Miguez, Carlos | Frias, João | Antunes, Joana Cepeda | Sobral, Paula | Santos, Isabelina | Micaêlo, Cristina | Ferreira, Ana María
We analyzed polychlorinated biphenyls (PCBs), dichlorodiphenyl dichloroethane and its metabolites, hexachlorocyclohexanes (HCHs), polycyclic aromatic hydrocarbons (PAHs), and hopanes, in plastic resin pellets collected from nine locations along the Portuguese coast. Concentrations of a sum of 13 PCBs were one order of magnitude higher in two major cities (Porto: 307ng/g-pellet; Lisboa: 273ng/g-pellet) than in the seven rural sites. Lower chlorinated congeners were more abundant in the rural sites than in the cities, suggesting atmospheric dispersion. At most of the locations, PAH concentrations (sum of 33 PAH species) were ∼100 to ∼300ng/g-pellet; however, three orders of magnitude higher concentrations of PAHs, with a petrogenic signature, were detected at a small city (Sines). Hopanes were detected in the pellets at all locations. This study demonstrated that multiple sample locations, including locations in both urban and remote areas, are necessary for country-scale pellet watch.
Показать больше [+] Меньше [-]Monitoring of a wide range of organic micropollutants on the Portuguese coast using plastic resin pellets Полный текст
2013
Mizukawa, Kaoruko | Takada, Hideshige | Ito, Maki | Geok, Yeo Bee | Hosoda, Junki | Yamashita, Rei | Saha, Mahua | Suzuki, Satoru | Miguez, Carlos | Frias, João | Antunes, Joana Cepeda | Sobral, Paula | Santos, Isabelina | Micaelo, Cristina | Ferreira, Ana Maria
We analyzed polychlorinated biphenyls (PCBs), dichlorodiphenyl dichloroethane and its metabolites, hexachlorocyclohexanes (HCHs), polycyclic aromatic hydrocarbons (PAHs), and hopanes, in plastic resin pellets collected from nine locations along the Portuguese coast. Concentrations of a sum of 13 PCBs were one order of magnitude higher in two major cities (Porto: 307. ng/g-pellet; Lisboa: 273. ng/g-pellet) than in the seven rural sites. Lower chlorinated congeners were more abundant in the rural sites than in the cities, suggesting atmospheric dispersion. At most of the locations, PAH concentrations (sum of 33 PAH species) were ∼100 to ∼300. ng/g-pellet; however, three orders of magnitude higher concentrations of PAHs, with a petrogenic signature, were detected at a small city (Sines). Hopanes were detected in the pellets at all locations. This study demonstrated that multiple sample locations, including locations in both urban and remote areas, are necessary for country-scale pellet watch. | This research was financially supported by Mitsui and Co. Ltd., Environment Fund for their financial support (Project R11-G4-1053) and Grants-in-Aid from the Ministry of Education and Culture of Japan (Project No. 22254001). We also appreciate to be supported by Fundação para a Ciência e Tecnologia, Portugal for their financial support through the project POIZON reference PTDC/MAR/102677/2008 and fellowship reference SFRH/BD/74772/2010. | published
Показать больше [+] Меньше [-]Perfluorinated compounds: Levels, trophic web enrichments and human dietary intakes in transitional water ecosystems Полный текст
2013
Renzi, Monia | Guerranti, Cristiana | Giovani, Andrea | Perra, Guido | Focardi, Silvano E.
The results of a study on levels of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), analyzed in terms of HPLC-ESI-MS in water, sediment, macrophyte, bivalve, crustacean and fish samples, are reported here. The aim of the research is to define, for the first time, PFOA/S levels in a heavily human-stressed transitional water ecosystem (Orbetello lagoon, Italy) and evaluate trophic web enrichments and human dietary intakes. The results obtained show that: (i) levels significantly higher than those reported in the literature were found in mussels, clams and crabs; (ii) the river is a significant pollution source; (iii) although absolute levels are relatively low, macroalgae proliferation contributes to redistribute pollutants from river-affected areas throughout the entire lagoon basin; (iv) to the best of our current knowledge, water-filtering species considered in this study are the most exposed to PFOA/S pollution; (v) human daily dietary intakes of PFOA/S through Slow Food-endorsed product consumption are below maximum tolerable levels suggested by the EFSA.
Показать больше [+] Меньше [-]Developing human capital for successful implementation of international marine scientific research projects Полный текст
2013
Morrison, R.J. | Zhang, J. | Urban, E.R. | Hall, J. | Ittekkot, V. | Avril, B. | Hu, L. | Hong, G.H. | Kidwai, S. | Lange, C.B. | Lobanov, V. | Machiwa, J. | San Diego-McGlone, M.L. | Oguz, T. | Plumley, F.G. | Yeemin, T. | Zhu, W. | Zuo, F.
The oceans play a crucial role in the global environment and the sustainability of human populations, because of their involvement in climate regulation and provision of living and non-living resources to humans. Maintenance of healthy oceans in an era of increasing human pressure requires a high-level understanding of the processes occurring in the marine environment and the impacts of anthropogenic activities. Effective protection and sustainable resource management must be based, in part, on knowledge derived from successful research. Current marine research activities are being limited by a need for high-quality researchers capable of addressing critical issues in broad multidisciplinary research activities. This is particularly true for developing countries which will require the building of capacity for marine scientific research. This paper reviews the current activities aimed at increasing marine research capacity in developing and emerging countries and analyses the challenges faced, including: appropriate alignment of the research goals and societal and policy-relevant needs; training in multidisciplinary research; increasing capacity for overall synthesis of scientific data; building the capacity of technical staff; keeping highly qualified personnel in marine scientific research roles; cross-cultural issues in training; minimising duplication in training activities; improving linkages among human capital, project resources and infrastructure. Potential solutions to these challenges are provided, along with some priorities for action aimed at improving the overall research effort.
Показать больше [+] Меньше [-]Abundance of class 1–3 integrons in South Carolina estuarine ecosystems under high and low levels of anthropogenic influence Полный текст
2013
Uyaguari, Miguel I. | Scott, Geoffrey I. | Norman, R Sean
The impact of human activity on the spread of antibiotic resistant bacteria throughout coastal estuarine ecosystems is not well characterized. It has been suggested that laterally transferred genetic agents, such as integrons, play a role in the spread of resistant bacteria throughout ecosystems. This study compares the distribution of three integron classes throughout a coastal estuarine ecosystem. To determine integron distribution patterns, DNA was extracted from sediment and water collected at seven sites throughout two estuaries with different levels of anthropogenic input and integrons analyzed using quantitative PCR. The data show that while all three integron classes are present, the relative abundance is different, with class 2 integrons significantly elevated in areas of high anthropogenic input and class 1 integrons elevated in areas of low input. Our results provide a foundation for using integron gene distribution as a biomarker of urban impact on antibiotic resistance gene flow and ecosystem health.
Показать больше [+] Меньше [-]Sedimentary PBDEs in urban areas of tropical Asian countries Полный текст
2013
Kwan, Charita S. | Takada, Hideshige | Mizukawa, Kaoruko | Saha, Mahua | Rinawati, | Santiago, Evangeline C.
Polybrominated diphenyl ethers (PBDEs) were measured in surface sediment samples collected from urban canals or rivers in Lao PDR, Cambodia, Vietnam, India, Indonesia, Thailand, the Philippines, Malaysia and Japan. The total PBDE concentrations in the sediments ranged from 0.83 to 3140ng/g dry wt. BDE-209 was predominant, ranging from 43% to 97% of total PBDEs, followed by nona-BDEs and some detectable concentrations of BDEs 47, 49, 99, 100, 153, 154 and 183. Sedimentary PBDE levels in Malaysia, Cambodia, the Philippines and Thailand were generally higher than those reported for highly industrialized countries. Spatial distribution of PBDEs indicated that inland sources may impact coastal areas. The presence of BDE congeners which are not contained in technical mixtures and the higher proportions of nona-BDEs relative to BDE-209 in the sediments were identified as indicators of debromination. BDE-209 was possibly debrominated under anaerobic conditions in some of the sediment samples.
Показать больше [+] Меньше [-]Good Environmental Status of marine ecosystems: What is it and how do we know when we have attained it? Полный текст
2013
Borja, Angel | Elliott, Mike | Andersen, Jesper H. | Cardoso, Ana C. | Carstensen, Jacob | Ferreira, João G. | Heiskanen, Anna-Stiina | Marques, João C. | Neto, João M. | Teixeira, Heliana | Uusitalo, Laura | Uyarra, María C. | Zampoukas, Nikolaos
The European Marine Strategy Framework Directive (MSFD) requires EU Member States (MS) to achieve Good Environmental Status (GEnS) of their seas by 2020. We address the question of what GEnS entails especially with regard to the level at which targets are set (descriptors, criteria, indicators), to scales for assessments (regional, sub-divisions, site-specific), and to difficulties in putting into practice the GEnS concept. We propose a refined and operational definition of GEnS, indicating the data and information needed to all parts of that definition. We indicate the options for determining when GEnS has been met, acknowledge the data and information needs for each option, and recommend a combination of existing quantitative targets and expert judgement. We think that the MSFD implementation needs to be less complex than shown for other similar directives, can be based largely on existing data and can be centred on the activities of the Regional Seas Conventions.
Показать больше [+] Меньше [-]Microplastic pollution in the surface waters of the Laurentian Great Lakes Полный текст
2013
Eriksen, Marcus | Mason, Sherri | Wilson, Stiv | Box, Carolyn | Zellers, Ann | Edwards, William | Farley, Hannah | Amato, Stephen
Neuston samples were collected at 21 stations during an ∼700 nautical mile (∼1300km) expedition in July 2012 in the Laurentian Great Lakes of the United States using a 333μm mesh manta trawl and analyzed for plastic debris. Although the average abundance was approximately 43,000 microplastic particles/km2, station 20, downstream from two major cities, contained over 466,000particles/km2, greater than all other stations combined. SEM analysis determined nearly 20% of particles less than 1mm, which were initially identified as microplastic by visual observation, were aluminum silicate from coal ash. Many microplastic particles were multi-colored spheres, which were compared to, and are suspected to be, microbeads from consumer products containing microplastic particles of similar size, shape, texture and composition. The presence of microplastics and coal ash in these surface samples, which were most abundant where lake currents converge, are likely from nearby urban effluent and coal burning power plants.
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