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A directional passive air sampler for monitoring polycyclic aromatic hydrocarbons (PAHs) in air mass Полный текст
2008
Tao, S. | Liu, Y.N. | Lang, C. | Wang, W.T. | Yuan, H.S. | Zhang, D.Y. | Qiu, W.X. | Liu, J.M. | Liu, Z.G. | Liu, S.Z. | Yi, R. | Ji, M. | Liu, X.X.
A passive air sampler was developed for collecting polycyclic aromatic hydrocarbons (PAHs) in air mass from various directions. The airflow velocity within the sampler was assessed for its responses to ambient wind speed and direction. The sampler was examined for trapped particles, evaluated quantitatively for influence of airflow velocity and temperature on PAH uptake, examined for PAH uptake kinetics, calibrated against active sampling, and finally tested in the field. The airflow volume passing the sampler was linearly proportional to ambient wind speed and sensitive to wind direction. The uptake rate for an individual PAH was a function of airflow velocity, temperature and the octanol–air partitioning coefficient of the PAH. For all PAHs with more than two rings, the passive sampler operated in a linear uptake phase for three weeks. Different PAH concentrations were obtained in air masses from different directions in the field test. A novel directional passive air sampler was developed and tested for monitoring PAHs in air masses from different directions.
Показать больше [+] Меньше [-]Assessment of pollution along the Northern Iberian shelf by the combined use of chemical and biochemical markers in two representative fish species Полный текст
2008
Fernandes, Denise | Andreu-Sánchez, Oscar | Bebianno, Maria Joao | Porte, Cinta
Assessment of pollution along the Northern Iberian shelf by the combined use of chemical and biochemical markers in two representative fish species Полный текст
2008
Fernandes, Denise | Andreu-Sánchez, Oscar | Bebianno, Maria Joao | Porte, Cinta
Muscle concentrations of organochlorinated compounds as well as biliary levels of polycyclic aromatic hydrocarbons (PAHs) and alkylphenols (APEs) were determined in two different fish species, the four-spotted megrim (Lepidorhombus boscii) and the pouting (Trisopterus luscus) collected along the Northern Iberian coast. Additionally, a set of biochemical markers namely, 7-ethoxyresorufin O-deethylase (EROD), UDP-glucuronosyltransferase (UGT) and catalase (CAT) were measured in liver subcellular fractions. Chemical analysis indicated geographical differences in pollutant loads that were further reinforced by biomarker responses. Thus, EROD activity showed a good correlation with the amount of PCBs bioaccumulated in muscle tissue of both fish species. Elevated UGT activity was observed in those individuals highly exposed to APEs and 1-naphthol. The study reinforces the need to select representative sentinel species from different habitats for biomonitoring purposes and provides further support for the use of biomarkers in assessing the health of coastal areas.
Показать больше [+] Меньше [-]Assessment of pollution along the Northern Iberian shelf by the combined use of chemical and biochemical markers in two representative fish species Полный текст
2008
Fernandes, D | Andreu-Sánchez, Oscar | Bebianno, Maria João | Porte, Cinta
Muscle concentrations of organochlorinated compounds as well as biliary levels of polycyclic aromatic hydrocarbons (PAHs) and alkylphenols (APEs) were determined in two different fish species, the four-spotted megrim (Lepidorhombus boscii) and the pouting (Trisopterus luscus) collected along the Northern Iberian coast. Additionally, a set of biochemical markers namely, 7-ethoxyresorufin O-deethylase (EROD), UDP-glucuronosyltransferase (UGT) and catalase (CAT) were measured in liver subcellular fractions. Chemical analysis indicated geographical differences in pollutant loads that were further reinforced by biomarker responses. Thus, EROD activity showed a good correlation with the amount of PCBs bioaccumulated in muscle tissue of both fish species. Elevated UGT activity was observed in those individuals highly exposed to APEs and 1-naphthol. The study reinforces the need to select representative sentinel species from different habitats for biomonitoring purposes and provides further support for the use of biomarkers in assessing the health of coastal areas. | Spanish Government BES-2003-0163, Spanish National Plan for Research VEM2003-20068-C05-01 | info:eu-repo/semantics/publishedVersion
Показать больше [+] Меньше [-]Persistent organic pollutants in soils and sediments from James Ross Island, Antarctica Полный текст
2008
Klánová, J. | Matykiewiczová, N. | Máčka, Z. | Prošek, P. | Láska, K. | Klán, P.
Soil and sediment samples from James Ross Island were analyzed for their PCB, OCP and PAH contents. Soil concentrations ranged between 0.51 and 1.82 ng g-1 for seven indicator PCB congeners, between 0.49 and 1.34 ng g-1 for HCH congeners, between 0.51 and 3.68 ng g-1 for the sum of p,p'-DDT, DDE, and DDD, and between 34.9 and 171 ng g-1 for the sum of 16 EPA PAHs. Sediment levels from 0.32 to 0.83 ng g-1 were found for PCBs, from 0.14 to 0.76 ng g-1 for HCHs, from 0.19 to 1.15 ng g-1 for DDTs, and from 1.4 to 205 ng g-1 for PAHs. A prevalence of low-mass PAHs, less chlorinated PCBs, and more volatile chemicals indicates that the long-range atmospheric transport from populated areas of Africa, South America, and Australia is the most probable contamination source for the solid matrices in James Ross Island. A survey of soil, sediment and air contamination in James Ross Island, Antarctica serves as a baseline study for evaluation of an anthropogenic impact of the new research facility.
Показать больше [+] Меньше [-]Revealing source signatures in ambient BTEX concentrations Полный текст
2008
Zalel, Amir | Yuval | Broday, David M.
Management of ambient concentrations of Volatile Organic Compounds (VOCs) is essential for maintaining low ozone levels in urban areas where its formation is under a VOC-limited regime. The significant decrease in traffic-induced VOC emissions in many developed countries resulted in relatively comparable shares of traffic and non-traffic VOC emissions in urban airsheds. A key step for urban air quality management is allocating ambient VOC concentrations to their pertinent sources. This study presents an approach that can aid in identifying sources that contribute to observed BTEX concentrations in areas characterized by low BTEX concentrations, where traditional source apportionment techniques are not useful. Analysis of seasonal and diurnal variations of ambient BTEX concentrations from two monitoring stations located in distinct areas reveal the possibility to identify source categories. Specifically, the varying oxidation rates of airborne BTEX compounds are used to allocate contributions of traffic emissions and evaporative sources to observed BTEX concentrations. BTEX sources are identified from temporal variations of ambient concentration.
Показать больше [+] Меньше [-]Cadmium accumulation and its effect on the in vitro growth of woody fleabane and mycorrhized white birch Полный текст
2008
Fernández, R. | Bertrand, A. | Casares, A. | García, R. | González, A. | Tamés, R.S.
The effect of Cd on woody fleabane (Dittrichia viscosa (L.) Greuter) and white birch (Betula celtiberica Rothm. & Vasc.) was examined. Woody fleabane and white birch were grown in vitro in Murashige, T., Skoog, F., [1962. A revised medium for rapid growth and bioassays with tobacco tissue cultures. Physiol. Plant. 15, 473-479] (MS) plus Cd (10 mg Cd kg-1) and except for root length in white birch, plant development was inhibited when Cd was added. Cd accumulation in above-ground tissues showed differences among clones, reaching 1300 and 463 mg Cd kg-1 dry wt. in selected clones of woody fleabane and white birch, respectively. Tolerance of Paxillus filamentosus (Scop) Fr. to Cd was also examined before mycorrhization. Plants of mycorrhized white birch grown in the presence of Cd had a better development and accumulated more Cd in their shoots than the non-mycorrhized ones. The use of selected clones of woody fleabane and the mycorrhization of white birch enhance extraction efficiency from contaminated soils in phytoremediation programs. The high accumulation of Cd observed in selected clones of Dittrichia viscosa and mycorrhized Betula celtiberica grown in vitro implies a potential application for phytoextraction.
Показать больше [+] Меньше [-]Interactive effects of O3 exposure on California black oak (Quercus kelloggii Newb.) seedlings with and without N amendment Полный текст
2008
Handley, T. | Grulke, N.E.
We examined the short-term separate and combined effects of simulated nitrogen (N) deposition (fertilization) and ozone (O3) exposure on California black oak seedlings (Quercus kelloggii Newb.), an ecologically important tree of the San Bernardino Mountains downwind of Los Angeles. Realistic concentrations of O3 were found to cause statistically and biologically significant negative effects on plant health, including lowered photosynthetic ability, lowered water use efficiency, and increased leaf chlorosis and necrosis. When subjected to abrupt changes in light levels, O3-exposed plants showed both a slower and smaller response than O3-free plants. Fertilized plants exhibited a significantly greater pre-to post-treatment decline in A at saturated [CO2] and a significantly lower level of post-treatment chlorosis than unfertilized plants. Fertilization tended to reduce plant sensitivity to O3.
Показать больше [+] Меньше [-]Water quality in the Tibetan Plateau: Metal contents of four selected rivers Полный текст
2008
Huang, Xiang | Sillanpaa, Mika | Duo, Bu | Gjessing, Egil T.
The water used by 85% of the Asian population originates in Tibetan Plateau. During April and May of 2006, water samples were collected from four major Asian rivers in the Plateau (i.e. the Salween, Mekong, Yangtze River and Yarlung Tsangpo) and analyzed for Cu, Pb, Zn, Ag, Mo, Cd, Co, Cr, Ni, Li, Mn, Al, Fe, Mg and Hg. The results showed that elements such as Mg were rather high in Tibetan rivers, giving a mean electrical conductance of 36 mS/m. In a few locations, the results also showed relatively high concentrations of Al and Fe (>1 mg/L). However, the concentrations of Cu, Zn, Ag, Cd, and Cr were generally low. Contamination with Pb was identified at a few locations in the Salween and Ni at a few sites in the Yangtze River. For the first time, total dissolved metal contents in source water of four major Asian rivers were evaluated at the same time.
Показать больше [+] Меньше [-]Perfluorinated and chlorinated pollutants as predictors of demographic parameters in an endangered seabird Полный текст
2008
Bustnes, Jan Ove | Erikstad, Kjell Einar | Lorentsen, Svein-Håkon | Herzke, Dorte
Despite global occurrence of several perfluorinated compounds (PFCs) the potential ecological effects of such substances on natural populations are not known. In endangered lesser black-backed gulls (Larus fuscus fuscus) on the Norwegian Coast, the blood concentrations of PFCs were as high as legacy organochlorines (OCs), and here we examined whether PFCs show associations similar to those of OCs to factors potentially affecting population growth, by evaluating relationships between contaminant concentrations and demographic parameters (reproductive performance and the probability of adults returning between breeding seasons). PFCs were not adversely associated with demographic parameters, while the most persistent OCs; notably PCB and p,p′-DDE, were adversely associated with early chick survival, and adult return rate. This study thus suggests that when the concentrations of PFCs and OCs are of similar magnitude in a gull population, OCs are more likely to cause adverse ecological effects. When the concentrations of PFCs and OCs are of similar magnitude in a population of gulls, OCs seem to have a stronger propensity for causing adverse ecological effects.
Показать больше [+] Меньше [-]Is selenium affecting body condition and reproduction in boreal breeding scaup, scoters, and ring-necked ducks Полный текст
2008
DeVink, J.M.A. | Clark, R.G. | Slattery, S.M. | Wayland, M.
Elevated levels of selenium (Se) have been detected in wintering and spring-staging lesser scaup. Here, we compared spring scaup Se and mercury (Hg) levels to those of ring-necked ducks and white-winged scoters, species exhibiting increasing and decreasing boreal populations, respectively. Mercury concentrations were low in all three species. Geometric mean (95%CI) liver Se concentrations were 6.2 (5.5-7.0), 4.6 (4.0-5.4), and 32.6 (28.4-37.3) mg/kg dry weight (dw) in scaup, ringnecks and scoters, respectively. Only scoter livers (66%) were above 33 mg/kg dw Se. Scaup and ringneck Se levels were unrelated to breeding status or lipid and protein levels; breeding scoters and females with greater lipid mass had higher Se than non-breeders. Egg and follicle concentrations in scaup and scoters were normal (mean [95%CI] = 2.3 [1.9-2.6] and 2.4 [2.1-2.7] mg/kg dw, respectively). Overall, we found no support for a relationship between selenium and boreal scaup and scoter declines, and discuss current Se threshold concentrations. Selenium is not affecting boreal scaup, ring-necked duck, or scoter body condition or reproduction.
Показать больше [+] Меньше [-]Life cycle responses of the midge Chironomus riparius to polycyclic aromatic compound exposure Полный текст
2008
Paumen, M.L. | Borgman, E. | Kraak, M.H.S. | Gestel, C.A.M van
During acute exposure, polycyclic aromatic compounds (PACs) act mainly by narcosis, but during chronic exposure the same compounds may exert sublethal life cycle effects. The aim of this study was therefore to evaluate the chronic effects of sediment spiked PACs on the emergence of the midge Chironomus riparius. Three isomer pairs were selected, and 28-day LC50 values and 50% emergence times (EMt50) were determined. Concentration-response relationships were observed for phenanthrene, acridine, phenanthridine and acridone. Anthracene and phenanthridone had no effect on total emergence, but did cause a delay in emergence. Calculated porewater LC50 values correlated well with logKow values, suggesting narcosis as mode of action. In contrast, effect concentrations for delay in emergence (EMt50) deviated from narcosis, suggesting a specific mode of action during chronic exposure. It is concluded that emergence is a powerful endpoint to detect life cycle effects of PACs on a key sediment inhabiting invertebrate. Emergence of Chironomus riparius is a sensitive endpoint to detect life cycle effects of PACs.
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