排序方式: 共有34条查询结果,搜索用时 15 毫秒
21.
Natalia Valero Inmaculada Aguilera Sabrina Llop Ana Esplugues Audrey de Nazelle Ferran Ballester Jordi Sunyer 《Environment international》2009,35(8):1196-1201
Determinants of outdoor, indoor and personal concentrations of nitrogen dioxide (NO2) were assessed in a subset of pregnant women of the Spanish INMA (Environment and Childhood) Study. Home indoor and outdoor NO2 concentrations were measured during 48 h with passive samplers for 50 and 58 women from the INMA cohorts of Valencia and Sabadell, respectively. Women from Sabadell also carried personal NO2 samplers during the same period. Data on time–activity patterns, socio-economic characteristics, and environmental exposures were obtained through questionnaires. Multiple linear regression models were developed to predict NO2 levels.In Valencia, median outdoor NO2 levels (42 µg/m3) were higher than median indoor levels (36 µg/m3). In Sabadell, personal NO2 showed the highest median levels (40 µg/m3), followed by indoor (32 µg/m3) and outdoor (29 µg/m3) levels. Personal exposure to NO2 correlated best with the indoor NO2 levels. Temporal and traffic-related variables were significant predictors for outdoor NO2 levels. Thirty-two percent of the indoor NO2 variability in the two cohorts was explained by outdoor NO2 levels and the use of the gas appliances. The model for personal exposure accounted for 59% of the variance in NO2 levels in Sabadell with four predictor variables (outdoor and indoor NO2 levels, time spent in outdoor environments and time exposed to a gas cooker). No significant association was found between personal or indoor NO2 levels and exposure to environmental tobacco smoke (ETS) at home.Personal NO2 levels were found to be strongly influenced by indoor NO2 concentrations. The study supports the use of time–activity patterns along with indoor measurements to predict personal exposure to traffic-related air pollution. 相似文献
22.
Nieto JM Sarmiento AM Olías M Canovas CR Riba I Kalman J Delvalls TA 《Environment international》2007,33(4):445-455
The Tinto and Odiel rivers are seriously affected by acid mine drainage (AMD) from the long-term mining activities in Iberian Pyrite Belt (IPB). As a consequence, the Huelva estuary is heavily contaminated by metals and metalloids. This study presents an estimation of the seasonal variation, and the dissolved contaminant load transported by both rivers from February 2002 to September 2004. Besides, toxicity and bioaccumulation tests with the sediments of the estuary have been conducted in order to measure the mobility of the toxic metals. Results show that the Tinto and Odiel rivers transport enormous quantities of dissolved metals to the estuary: 7900 t yr(-1) of Iron (Fe), 5800 t yr(-1) Aluminium (Al), 3500 t yr(-1) Zinc (Zn), 1700 t yr(-1) Copper (Cu), 1600 t yr(-1) Manganese (Mn) and minor quantities of other metals and metalloids. These values represent 37% of the global gross flux of dissolved Zn transported by rivers in to the ocean, and 15% of the global gross flux of dissolved Cu. These metals and metalloids usually sink in the estuarine sediments due to pH and salinity changes. The increase of salinity in the estuary favours the adsorption and trapping of metals. For this reason, the mobility and bioavailability of metals such as Zn, Cd and Cu is higher in sediments located in the area of fresh water influence that in sediments located in the marine influenced area of the estuary, showing a higher percentage of fractionation and bioaccumulation of these metals in the station influenced by the fresh water environment. 相似文献
23.
Inmaculada de Vicente Victoria Amores Francisco Guerrero Luis Cruz-Pizarro 《Die Naturwissenschaften》2010,97(7):627-635
Electron transport system (ETS) activity of sediments as an indication of microbial metabolic activity was examined in two
adjacent Mediterranean wetlands (southern Spain). We determined the spatio-temporal variation in ETS, and we explored the
potential biological [organic matter (OM), chlorophyll a (Chl a), aerobic and anaerobic bacteria] drivers of sediment ETS
activity. ETS activity was notably higher in the eutrophic Lake Nueva (34.91 μl O2 g−1 D.W. h−1) than in the hypertrophic Lake Honda (24.99 μl O2 g−1 D.W. h−1). Strong spatial differences were observed in ETS in both study sites. Highest ETS values were achieved at the surface sediment
at the deepest sampling station in each lake and a notable reduction in ETS with sediment depth was observed. By using linear
regression and multiple regression analysis, OM was identified as the best predictor of ETS in Lake Honda while Chl a was
the best predictor in Lake Nueva. The strong influence of OM supply on ETS activity in sediment from Lake Honda was the consequence
of the labile nature of sedimentary OM, while a more refractory OM (with a higher contribution of vascular plants) comprised
most of the sedimentary OM from Lake Nueva. By contrast, a large contribution of phytobenthos (supported by a higher lake
water transparency) to ETS has been recognized in sediments from Lake Nueva. In summary, the results of this study revealed
that the relative importance of planktonic primary producers (phytoplankton), benthic algae and vascular plants in the study
sites could explain the differences observed in the intensity of sediment ETS as well as in their drivers. 相似文献
24.
Nereida Jiménez de Oya Inmaculada Galindo Estela Escribano-Romero Ana-Belén Blázquez Julio Alonso-Padilla Nabil Halaihel José M. Escribano Juan-Carlos Saiz 《Food and environmental virology》2009,1(2):77-84
Hepatitis E virus (HEV) is a fecal-orally transmitted virus that is endemic in many geographical areas with poor sanitary
conditions and inadequate water supplies. In Europe, a low-endemic area, an increased number of autochthonous sporadic human
cases of patients infected with HEV strains of genotype 3, have been reported lately. The relatively high prevalence of HEV
genotype 3 infections in European pigs has raised concerns about a potential zoonotic transmission to humans. Determination
of HEV seroprevalence in pigs would help to clarify its incidence and possible zoonotic implications. To this purpose, we
have expressed and partially characterized swine genotype 3 HEV open reading frame-2 proteins upon infection of Sf21 insect
cells with recombinant baculoviruses. The use of the expressed proteins as diagnostic antigens for the detection of antibodies
to HEV has been further assayed with human and swine sera. 相似文献
25.
Treatment of municipal landfill leachate by catalytic wet air oxidation: Assessment of the role of operating parameters by factorial design 总被引:2,自引:0,他引:2
Anglada A Urtiaga A Ortiz I Mantzavinos D Diamadopoulos E 《Waste management (New York, N.Y.)》2011,31(8):1833-1840
The wet air oxidation (WAO) of municipal landfill leachate catalyzed by cupric ions and promoted by hydrogen peroxide was investigated. The effect of operating conditions such as WAO treatment time (15-30 min), temperature (160-200 °C), Cu2+ concentration (250-750 mg L−1) and H2O2 concentration (0-1500 mg L−1) on chemical oxygen demand (COD) removal was investigated by factorial design considering a two-stage, sequential process comprising the heating-up of the reactor and the actual WAO. The leachate, at an initial COD of 4920 mg L−1, was acidified to pH 3 leading to 31% COD decrease presumably due to the coagulation/precipitation of colloidal and other organic matter. During the 45 min long heating-up period of the WAO reactor under an inert atmosphere, COD removal values up to 35% (based on the initial COD value) were recorded as a result of the catalytic decomposition of H2O2 to reactive hydroxyl radicals. WAO at 2.5 MPa oxygen partial pressure advanced treatment further; for example, 22 min of oxidation at 200 °C, 250 mg L−1 Cu2+ and 0-1500 mg L−1 H2O2 resulted in an overall (i.e. including acidification and heating-up) COD reduction of 78%. Amongst the operating variables in question, temperature had the strongest influence on both the heating-up and WAO stages, while H2O2 concentration strongly affected the former and reaction time the latter. Nonetheless, the effects of temperature and H2O2 concentration were found to depend on the concentration levels of catalyst as suggested by the significance of their 3rd order interaction term. 相似文献
26.
A multibiomarker approach using the polychaete Arenicola marina to assess oil-contaminated sediments
Carmen Morales-Caselles Ceri Lewis Inmaculada Riba T. Ángel DelValls Tamara Galloway 《Environmental science and pollution research international》2009,16(6):618-629
Background, aim and scope
Marine and coastal sediments can accumulate substantial concentrations of metals and hydrocarbons, yet the consequences of this contamination for exposed biota in situ can be difficult to establish. Here, we examine the hypothesis that exposure to contaminated sediments can lead to detrimental effects in sediment-dwelling species. The combination of chemical and biological assessment allows the identification of the impact of chemical contamination, and their use as assessment tools is becoming increasingly important. 相似文献27.
Hartmann NB Buendia IM Bak J Baun A 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):3134-3137
In this study, aged aqueous suspensions of C(60) (nC(60)) were investigated in the respirometric OECD test for ready biodegradability. Two suspensions of nC(60) were prepared by stirring and aged under indirect exposure to sunlight for 36 months. ATR-FTIR analyses confirmed the presence of C(60)-structures in the suspensions. Samples of the nC(60) suspensions (20mg/l) were inoculated with activated sludge (30 mgTSS/L) and incubated in a mineral medium under aerobic conditions. Since no mineralisation of nC(60) was observed after 28 days of incubation, 5mg/l sodium acetate was added to the media. After additional 20 days, no mineralisation of nC(60) was observed. However, within a few days sodium acetate was completely mineralised, showing that the biomass was not inhibited by the presence of nC(60). Based on results from this simple approach, aged nC(60) can be classified as not ready biodegradable according to the standard OECD test procedure. 相似文献
28.
Alonso R Vivanco MG González-Fernández I Bermejo V Palomino I Garrido JL Elvira S Salvador P Artíñano B 《Environmental pollution (Barking, Essex : 1987)》2011,159(8-9):2138-2147
Tropospheric ozone (O(3)) is considered one of the most important air pollutants affecting human health. The role of peri-urban vegetation in modifying O(3) concentrations has been analyzed in the Madrid region (Spain) using the V200603par-rc1 version of the CHIMERE air quality model. The 3.7 version of the MM5 meteorological model was used to provide meteorological input data to the CHIMERE. The emissions were derived from the EMEP database for 2003. Land use data and the stomatal conductance model included in CHIMERE were modified according to the latest information available for the study area. Two cases were considered for the period April-September 2003: (1) actual land use and (2) a fictitious scenario where El Pardo peri-urban forest was converted to bare-soil. The results show that El Pardo forest constitutes a sink of O(3) since removing this green area increased O(3) levels over the modified area and over down-wind surrounding areas. 相似文献
29.
Hovorka Miloš Száková Jiřina García-Sánchez Mercedes Acebal Mercedes Blanc García-Romera Inmaculada Tlustoš Pavel 《Environmental science and pollution research international》2016,23(22):22614-22622
Environmental Science and Pollution Research - Olive oil production is one of the most relevant agroindustrial activities in the Mediterranean region and generates a huge amount of both solid and... 相似文献
30.
Dolores Reyman Adrián Saiz Bermejo Inmaculada Ramirez Uceda Miguel Rodriguez Gamero 《Environmental Chemistry Letters》2014,12(1):235-240
New renewable fuels are urgently needed due to increasing fossil fuel pollution. Biodiesel, which contains alkyl esters produced by transesterification of oils, is an alternative fuel. Nevertheless, the main problem of biodiesel is its high price. Costs can be reduced by replacement of the current homogeneous catalysts by heterogeneous catalysts; however, research for new catalysts is actually slowed by lengthy analytical techniques. Here, we set up a simple and rapid analytical method using Fourier transform infrared (FTIR) to monitor transesterification. Conversion of sunflower and recycled cooking oils to their corresponding methyl esters was easily measured using a linear correlation between the intensity of an infrared peak at 1,437 cm?1 and the percent conversion. The results obtained by infrared were validated by gas chromatography. We also studied the effect of 20 kHz ultrasonic irradiation on biodiesel synthesis. Using our FTIR method, we found that replacing mechanical stirring with an ultrasonic probe leads to quality biodiesel in 10 min for sunflower oil and 20 min for recycled cooking oil. 相似文献