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1.
The elemental composition of a group of airborne and settled grain dusts is reported. This survey was undertaken as part of a study to systematically describe the chemistry and morphology of these representative dusts. Our data show that airborne or settled grain dusts differ from each other with respect to elemental composition. Such fundamental differences may be related to previously observed differences in the biological activities of the dusts.  相似文献   

2.
Since 1972, at the University of Hohenheim in Stuttgart, Germany, airborne particulate matter (PM12 and then PM10) was continuously collected on filters and analyzed for environmentally relevant elements by X-ray fluorescence analysis. The resulting long-term time series are suitable for the investigation of trends and of seasonal variation. For the period 1972-2005, monthly and annual concentration mean values of 13 elements (Br, Ca, Cr, Cu, Fe, K, Mn, Ni, Pb, S, Ti, V, and Zn) in the air are presented. Trend curves were fitted and the mean yearly variation of the concentration for these elements was calculated and represented graphically. All trend curves show a diminution of the air pollution during this period, but to different extents. Mean trends in percent per year were calculated for each element both for the entire investigation period and for three data subsets of 10-11 years. Possible explanations are discussed in detail.  相似文献   

3.
9,10-Phenanthrenequinone (PQ), one of the components of atmospheric pollutants, has potent harmful effects on human health. PQ in airborne particulates collected in Nagasaki city was determined by HPLC with fluorescence derivatization. PQ extracted from airborne particulates using methanol was derivatized with benzaldehyde in the presence of ammonium acetate to give a fluorescent compound. The average concentration (mean+/-SD, n=52) of PQ found in airborne particulates collected from July 1997 to June 1998 was 0.287+/-0.128 ng m-3. Concentrations of PQ in winter were higher than those in summer. In a weekly variation study, PQ concentrations were higher during weekdays and lower at weekend. The levels of PQ were obviously correlated with those of phenanthrene (PH) that is considered as a parent compound of PQ. This observation suggested that PQ was emitted into the atmosphere from the same source as PH, or PQ was converted from PH in the atmosphere.  相似文献   

4.
Environmental Science and Pollution Research - The air quality monitoring in Rijeka started in the early 1970s and has been oriented to air pollution caused by the big industrial sources (new...  相似文献   

5.
Ambient airborne particulate matter (PM) in southwestern North America consists of naturally derived desert dust, plus anthropogenic inputs from several sources. Epiphytic lichens (Usnea sp.) in this region are a useful biomonitor for the airborne PM because they derive nutrients and moisture largely from incorporated atmospheric aerosols, and not by absorption from the host tree limb from which they are suspended. Using a broad-based sampling strategy from southern Chihuahua, Mexico, to northern New Mexico, USA, we show that select elemental abundance ratios and lead isotopes from epiphytic lichens are useful for distinguishing between sources of airborne PM, and for gauging anthropogenic inputs into desert ecosystems. Abundance patterns of the trace elements La, Nd, and Sm in the lichens suggest origination from continental crust, but rare earth elements display a pronounced enrichment relative to the major element Fe by a factor of about 5. This enrichment appears related to geologic weathering, aeolian transport, and grain-size biases toward trace-element-rich mineral grains in the arid setting. Using the metal Pb as an indicator of human inputs, epiphytic lichens typically show Pb enrichments by a factor of about 25–60 over typical upper crustal values. Regional-scale differences in Pb isotope ratios of these lichens relate to different pollutant sources in southwestern North America.  相似文献   

6.
Total element determination and chemical fractionation were carried out in airborne particulate matter (PM10) from the Cerrillos monitoring station in Santiago, Chile, sampled in July (winter), 1997–2003.Element concentration in the period under study (1997–2003) was statistically analyzed through cluster analysis in order to identify groups of elements having similar behavior along time. Elements such as Cd, Cu, Pb, Ni, As and Mg show a clear decrease in concentration with time. On the contrary, chromium increases its concentration almost linearly during the period.In order to estimate whether the presence of a certain element in PM10 matrix is mainly due to anthropogenic or natural processes, the enrichment factor of each element was determined.According to their behavior in the sequential extraction procedure, the elements were grouped by multivariate analysis in three clusters: (a) those mobile elements (Pb, Cd, Zn, Mn, Cu and As) which are weakly bound to the matrix (fractions 1 and 2) (b) those elements (V, Ti, and Cr) mainly bound to carbonates and oxides (fraction 3) and (c) the most immobile elements (Ni, Mo, Ca, Mg, Ba and Al), mainly bound to silicates and organic matter (fraction 4). A source of great concern is the fact that elements of such high toxicity as Pb, Cd and As are highly concentrated in both mobile fractions, indicating that these elements have a direct impact on the environment and on the health of the exposed population.  相似文献   

7.
8.
Levels of cocaine and other psychoactive substances in atmospheric particulate matter (PM) were determined in urban environments representing distinct social behaviours with regard to drug abuse: night-life, university and residential areas. Three cities (with population >1 million and <0.3 million inhabitants) were selected. Mean daily levels of drugs in PM were 11-336 pg/m3 for cocaine, 23-34 pg/m3 for cannabinoids, and 5-90 pg/m3 for heroin. The highest levels were recorded on weekends, with factors with respect to weekdays of 1-3 for cocaine, 1-2 for cannabinoids and 1.1-1.7 for heroin. Higher levels were detected in the night-life areas, pointing towards consumption and trafficking as major emission sources, and possibly ruling out drug manufacture. The similarities in temporal trends at all sites suggested a city-scale transport of psychoactive substances. Correlations were detected between cocaine and amphetamine consumption (r2 = 0.98), and between heroin and cannabinoids (r2>0.82).  相似文献   

9.
The genotoxicity associated with air pollution in the city of Canoas, Rio Grande do Sul (Brazil), was assessed in November (spring) and January (summer). We applied the somatic mutation and recombination test (SMART) in Drosophila melanogaster in its standard version with normal bioactivation (ST) and in its variant with increased cytochrome P450-dependent biotransformation capacity (HB). The data indicated the genotoxicity of TSP and PM10 collected in November, in both ST and HB crosses. The genotoxic activity of the PM10 material in the spring sample was exclusively associated with the induction of mitotic recombination, whereas the TSP genetic toxicity was due to both recombinational as well as point and/or chromosomal mutation events. Considering PM10 collected in January, a positive response--100% (17.10 m3/ml) concentration--was observed in the HB cross, which was not detected in the ST cross.  相似文献   

10.
Ambient air dust samples were collected from industrial, commercial and residential areas of four metropolitan cities (Delhi, Calcutta, Madras and Cochin) in India, and were analysed for 27 elements (As, Ba, Br, Ce, Co, Cr, Cs, Cu, Eu, Hf, Hg, Fe, Ga, La, Lu, Na, P, Sb, Sc, Se, Sr, Ta, Tb, Th, Rb, Yb and Zn) by Instrumental Neutron Activation Analysis (INAA). Samples were irradiated with thermal neutrons in a nuclear reactor for 1 day and counted by high resolution gamma spectrometry at different intervals. Several environmental standards such as Coal (SRM 1932b); Urban Particulate Matter (SRM 1648) from NIST, USA; Vehicle Exhaust from NIES, Japan; and Soil-5 from IAEA, Vienna were also analysed for quality assurance. The results reveal that the concentrations of several pollutant elements in dust samples from the four cities are highly variable. Wide differences were observed for elemental concentrations of As, Ba, Br, Cu, Cr, Hg, Fe, Sb, Se and Zn and these variations are explained in terms of their possible sources of origin.  相似文献   

11.
太仓大气细颗粒物的粒径分布及来源分析   总被引:2,自引:1,他引:2  
超大城市大气环境日益改善的同时,其周边卫星城市的大气环境将逐步得到关注.利用静电低压撞击器(ELPI)在线测量上海周边卫星城市太仓大气细颗粒物(PM2.5)粒子数浓度和质量浓度的粒径分布;结合太仓大气PM2.5样品中Ca、Ti、V、Cr、Mn、Fe、Co、Ni、Cu、Zn、As、Se、Sr、CA和Pb等15种元素的浓度...  相似文献   

12.
Indoor air quality has become a critical issue because people spend most of their time in the indoor environment. The factors that influence indoor air quality are very important to environmental sanitation and air quality improvement. This study focuses on monitoring air quality, colony counts, and bacteria species of the indoor air of a nursing care institution. The regular colony counts in two different wards range from 55 to 600 cfu m(-3) Regression analysis results indicate that the bacterial colony counts have close correlation with relative humidity or carbon dioxide (CO2) but not with carbon monoxide (CO) or ozone (O3). Real-time PCR was used to quantify the bacterial pathogens of nosocomial infection, including Acinetobacter baumannii, Citrobacter freundii, Escherichia coli, Klebsiella pneumoniae, and methicillin-sensitive Staphylococcus aureus. The most abundant bacteria species in the air of the nursing care institution is E. coli.  相似文献   

13.
Trifolium species, commonly known as clover species, have a cosmopolitan distribution and, as such, are used in many different traditional systems of medicine and consumed by many communities all over the world. In this study, the elemental distribution and nutritional value of five edible Trifolium species, namely, Trifolium africanum, Trifolium burchellianum, Trifolium repens, Trifolium dubium and Trifolium pratense were investigated to evaluate the potential of these plant species to alleviate malnutrition, thereby contributing toward the fight against food insecurity. Trifolium species were found to be a rich alternate source of essential nutrients with concentrations of elements being in decreasing order of Ca > Mg > Fe > Mn > Zn > Se > Cu > Cr > Pb > Ni > Co > Cd > As and with adequate levels of lipids (4.2 to 8.6%), proteins (35.1 to 45.4%) and carbohydrates (26.7 to 47.0%). Trifolium species were found to be rich in Se (contributing greater than 516% toward its RDA) with T. dubium having a concentration of 0.53 mg 10 g?1, dry mass, which is higher than Brazil nuts. T. pratense was found to be the most suitable species for human consumption due to it having low levels of toxic metals (As, Cd and Pb) while being rich in macro- and micro-elements, especially Fe (7.84 mg 10 g?1, dry mass) and Se (0.36 mg 10 g?1, dry mass).  相似文献   

14.
The present situation and future projections regarding shellfish culture in Chile are analysed. Production has increased exponentially, mainly of the 'Chilean mussel' Mytilus chilensis (Hupe) and the 'northern scallop' Argopecten purpuratus (Lamarck). At present, seven species are cultured, two of which were introduced. The total invertebrate production corresponding to cultures has increased from 1.6% to 38% over the last 15 years. The effects of the following factors on present and future levels of shellfish culture in Chile are discussed: disease, fouling, borers, red tide and environmental variations caused by the cultures themselves. Potential culture of approximately 70 commercially endemic species not only constitutes an economic option, but also favours their conservation.  相似文献   

15.
The elemental and radioactivity analyses of rock and soil samples from some selected sites in southwestern Nigeria have been done. Measurements of the elemental compositions and activity concentrations of 238U, 232Th, and 40K were carried out using nuclear activation analysis technique and gamma spectrometry with high purity germanium detector, respectively. The results obtained provide reference data, allowing observation of possible future changes due to future radiological contamination. The activity concentrations of the natural radionuclides measured in the rocks were higher than those of the soils. The mean concentration of the major and minor elements in the rock and soil samples followed the order Al > Ca > Na > K > Mg > Fe > Ti and Mn > Ba > V > As > Cr > Ni > Zn > Cu, respectively. The radiological hazard and pollution risks associated with the natural radionuclides and heavy metals in the samples were assessed. The results obtained for the annual effective dose equivalent (AEDE), internal hazard, external hazard, and representative gamma indices were lower than their respective maximum permissible limit of 1 mSv y?1 for AEDE and 1 for internal hazard, external hazard, and representative gamma indices as recommended by the International Commission on Radiological Protection (ICRP). The results of the geo-accumulation index, enrichment factor, and the pollution load index indicate that the soils of the study area are uncontaminated with the heavy metals measured except Ado-Ekiti, Ikere, and Igbara-Odo soils which are moderately contaminated with Arsenic (As).  相似文献   

16.
北京市春季大气颗粒物污染特性研究   总被引:3,自引:0,他引:3  
为研究北京市春季大气颗粒物污染特性,2008年3月至2008年5月,对北京市西三环大气颗粒物进行采样分析.测定了总悬浮颗粒物(TSP)与可吸入颗粒物(PM10)的日平均质量浓度,使用扫描电子显微镜(SEM)观察大气颗粒物的微观形貌,并通过X射线能谱仪(EDX)对样品中的元素组成进行分析.结果表明,TSP和PM10日平均质量浓度以初春最高,春天次之,春夏交际最低;PM10/TSP以春夏交际最高,初春次之,春天最低;大气颗粒物形态有规则和不规则2类,以不规则形态居多,同时发现花粉颗粒存在.EDX分析表明,大气颗粒物所附着的重金属中Pb所占的质量分散最高,并且集中吸附在细粒子颗粒物上.  相似文献   

17.
An experimental study was made of the adsorption of aluminium by fine particulates from Whitray Beck, a hill stream in NW England. Adsorption increased with Al(3) activity, pH and concentration of particles, and could be quantitatively described by the empirical equation: [Formula: see text] [particles] where square brackets indicate concentrations, curly brackets, activities, and alpha, beta and gamma are constants with values of 5.14x10(-10) (mol litre(-1))(2.015) (g particles litre(-1))(-1), 0.457, and 1.472, respectively. For the experimental data, the equation gave a correlation ratio of 0.99. The equation accounts reasonably well for the adsorption of Al by particulates from seven other streams. In applying the equation, it must be borne in mind that the desorption kinetics of Al depend on pH, and rapid reversibility (<15min) can only be assumed for pHor=10%) of total monomeric Al.  相似文献   

18.
19.
This report summarizes the important results which were presented at an international symposium on particulate elemental carbon in the atmosphere. The “Particulate Carbon: Atmospheric Life Cycle” symposium was sponsored by General Motors Research Laboratories on October 12–14, 1980. Supplemental background data are included.  相似文献   

20.
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