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1.
Atmospheric particulate matter (APM) was collected at three sampling sites in Beijing, China, from February to June 1998. The concentrations of rare earth elements (REE) and cobalt (Co), zinc (Zn), copper (Cu), cadmium (Cd) and lead (Pb) in the APM were determined by inductively coupled plasma mass spectrometry (ICP-MS). The results obtained in Beijing, China, were compared to that obtained in Delft, the Netherlands, in 1997. The influence of coal combustion was considered. The results demonstrated that the content of APM, the concentrations of REE and Co, Zn, Cd, Pb in the APM in Beijing, China, were higher than that in Delft, the Netherlands. From the ratios of La to Ce, and La to Sm, which may be used as tracers for the origin of the REE, it is concluded that the origins of REE in China differ from those in the Netherlands.  相似文献   

2.
Lichens as biomonitors and neutron activation analysis as analytical technique have been employed to study the distribution of trace elements (TE) in a mountain region of north Italy (Biella) characterized by settlements of wool industry. Samples of airborne particulate matter collected onto filters, different species of lichens and samples of soils have been analyzed for the calculation of the enrichment factors (EFs) of more than 25 TE. By comparison of the corresponding EFs, the most suitable lichen species (Parmelia caperata) was selected as specific TE biomonitor of the area investigated. Samples of this lichen were collected and analyzed for the evaluation of the TE distribution in four different locations. The results obtained from the analysis of the lichens gave information about the predominant direction of pollutants transportation, while those related to the concentrations found in the air particulate allowed the evaluation of the degree of the local TE atmospheric pollution.  相似文献   

3.
Two former uranium mines and a uranium reprocessing factory in the city of Aktau, Kazakhstan, may represent a risk of contaminating the surrounding areas by uranium and its daughter elements. One of the possible fingerprinting tools for studying the environmental contamination is using plant samples, collected in the surroundings of this city in 2007 and 2008. The distribution pattern of environmental pollution by uranium and thorium was evaluated by determining the thorium and uranium concentrations in plant samples (Artemisia austriaca) from the city of Aktau and comparing these results with those obtained for the same species of plants from an unpolluted area (town of Kurchatov). The determination of the uranium and thorium concentrations in different parts of A. austriaca plants collected from the analyzed areas demonstrated that the main contamination of the flora in areas surrounding the city of Aktau was due to dust transported by the wind from the uranium mines. The results obtained demonstrate that all the areas surrounding Aktau have a higher pollution level due to thorium and uranium than the control area (Kurchatov). A few “hot points” with high concentrations of uranium and thorium were found near the uranium reprocessing factory and the uranium mines.  相似文献   

4.
It is of great interest to evaluate if there is a relationship between possible sources and trace elements using biomonitoring techniques. In this study, tree bark samples of 171 trees were collected using a biomonitoring technique in the inner city of São Paulo. The trace elements (Al, Ba, Ca, Cl, Cu, Fe, K, Mg, Mn, Na, P, Rb, S, Sr and Zn) were determined by the energy dispersive X-ray fluorescence (EDXRF) spectrometry. The Principal Component Analysis (PCA) was applied to identify the plausible sources associated with tree bark measurements. The greatest source was vehicle-induced non-tailpipe emissions derived mainly from brakes and tires wear-out and road dust resuspension (characterized with Al, Ba, Cu, Fe, Mn and Zn), which was explained by 27.1% of the variance, followed by cement (14.8%), sea salt (11.6%) and biomass burning (10%), and fossil fuel combustion (9.8%). We also verified that the elements related to vehicular emission showed different concentrations at different sites of the same street, which might be helpful for a new street classification according to the emission source. The spatial distribution maps of element concentrations were obtained to evaluate the different levels of pollution in streets and avenues. Results indicated that biomonitoring techniques using tree bark can be applied to evaluate dispersion of air pollution and provide reliable data for the further epidemiological studies.  相似文献   

5.
Specimens of the mussel Bathymodiolus azoricus were collected from Menez Gwen, a relatively shallow (850 m) hydrothermal vent field on the Mid-Atlantic Ridge. Each bivalve shell (n = 21) was individually cleaned by selective chemical. The residual crystal matrix of each shell was individually analysed for the concentrations of the minor elements magnesium and strontium and the trace elements iron, manganese, copper and zinc. The chemical composition of the crystal matrix is unusual. B. azoricus is identified as a species having one of the most strontium impoverished shells amongst the marine molluscs. For a bimineral species the magnesium concentration is also extraordinary low. Despite originating from a trace metal rich environment; the metal concentrations in the shells were exceptionally low. Mean concentrations of iron, manganese, copper and zinc were 20.6, 3.7, 0.6 and 9.4 microg g(-1) respectively. Minor and trace element concentrations exhibited a marked intra-population variability. Copper concentrations increased and iron and zinc concentrations decreased with increasing shell weight. Due to its insensitivity to the high environmental levels of trace elements and the variability in intra-population concentrations induced by shell weight the crystal matrix of the shell of B. azoricus has little potential for use in environmental trace metal monitoring in areas contiguous to deep-sea hydrothermal vents.  相似文献   

6.
Results of a recent intercomparison on the determination of trace elements in simulated air filter samples are reported. A large scatter of results is obtained for some elements and systematic differences between laboratories are observed. The performance of different methods, in particular neutron activation analysis and atomic absorption spectrophotometry, used by the various laboratories is discussed (air filter analysis; intercomparison; trace elements; control charts).  相似文献   

7.
Sediment samples were collected during the research vessel Umitaka-Maru cruises in the Gulf region from 15–16 December 1993 and 15–27 December 1994, from 19 and 24 locations, respectively. These samples were subjected to trace metal analysis to determine the 1991 Gulf War oil spill environmental impact in the area. The samples investigated are texturally classified into two main sediment classes: sand and mud. The total concentrations of lead, nickel, and vanadium found in the sediments from individual stations were investigated. The differences in trace metal concentrations reflect the variation in the overall composition of their host sediments. To better appraise the trace element composition of their host sediments and to determine the factors governing the trace metal distribution, the data were sub-divided into five groups among 1993 collections and seven groups during 1994. The concentration ranges of all three metals, lead (0.2–4.85), nickel (4.90–86.00), and vanadium (2.00–38.00) varied in different stations among the groups. The partitioning of trace elements between the detrial and non-detrital fractions of the sediments shows that: 1) The high concentrations of elements in mud is coupled with the increase in the detrital fraction; 2) In muddy sand sediments, nickel is bonded to the structural lattice of detrital minerals, whereas vanadium and lead held in the environmentally mobile fraction; and, 3) In sandy mud sediments, Ni is found in the detrital fraction, whereas V to slightly less extent and Pb show their non-detrital nature. The data were compared with unpolluted sediments throughout the ROPME Sea and worldwide, so the effect of anthropogenic enrichment upon the absolute concentration of the elements is minimal.  相似文献   

8.
The results of a survey of outdoor radon concentrations in Milan are reported. Measurements were performed hourly over a continuous four year period from January 1997 to December 2000. Radon concentration was obtained by two means: both direct measurement of radon; and measurement of its decay products. The average daily pattern of radon concentration featured a minimum in the late afternoon and a maximum in the early hours of the morning. A seasonal pattern with higher concentrations in winter than in summer (from around 15 Bq m(-3) in winter to around 5 Bq m(-3) in summer) was also observed. Similar average annual values of around 10 Bq m(-3) were obtained. The annual effective outdoor radon dose was found to be 0.12 mSv. The variation from minimum in the afternoon to maximum the following morning was found to be a good indicator of the height of the nocturnal mixing layer. The variation between maximum and minimum levels on the same day is an index of the maximum height of the mixing layer. Furthermore, our long term measurements of radon have permitted us to examine the dispersion characteristics of the atmosphere over Milan, and to establish the frequency of conditions unfavourable to the dispersion of atmospheric pollutants.  相似文献   

9.
The chemical composition of 73 surface soil samples collected at the city of Antalya were analyzed for major, minor and trace elements to assess distribution of soil pollution, due to deposition of pollution-derived particles from the atmosphere. Comparison with data from rural area and distribution maps demonstrated that the composition of soil by metals is not significantly modified by anthropogenic activities in most of the city and its surroundings. In these areas, observed concentrations can be largely accounted for by occurrence of elements in aluminasilicate matrix of soil. However, soil composition is altered substantially close to major industries and at the settlement districts. In such limited areas, concentrations of anthropogenic elements such as Cd, Pb, Zn, Cu and Cr are factors of 20-50 higher than their concentrations in unperturbed soil. Factor analysis revealed three groups of elements that differ in their distributions. One of these components is unperturbed soil component, which is distributed uniformly in the study area; the second one is polluted soil, which is mostly confined to settlement areas and around industries; and the third is a mixed marine and motor vehicle impacted soil component, which occurred at the coastal parts of the city.  相似文献   

10.
Temporal changes in the amounts of trace elements (As, Co, Cu, Mn, Ni, Pb, and Zn) and their correlations with temporal changes in charcoal abundance in age-dated sediments collected from Lake Thompson in Patagonia, Chile, attest to the substantial pyrogenic remobilization of contaminants that occurred in Patagonia during the mid-1900s. This remobilization was concurrent with the extensive slash and burn period in the region during that period. The changes in concentrations of Co, Cu, and Ni in relation to charcoal abundance in the lacustrine sediments over time were small compared to those of As, Mn, Pb, and Zn. However, the relatively low enrichment factors of all those trace elements, normalized to Fe, indicate that they were predominantly derived from local, natural sources impacted by fires rather than industrial sources. The primarily local source of Pb in the sediments was corroborated by the temporal consistency of its isotopic ratios (206Pb/207Pb:208Pb/206Pb), which were similar to previously reported values for natural lead in Central and Southern Chile. However, the pyrogenic remobilization of both natural and industrial trace elements by forest fires in Chile and elsewhere is expected to rise as a consequence of climate change, which is projected to increase both the frequency and intensity of forest fires on a global scale.  相似文献   

11.
Three types of sea alga distributed along the Syrian coast have been collected and analyzed for radioactivity and trace elements. Results have shown that (137)Cs concentrations in all the analyzed sample were relatively low (less than 1.2 Bq kg(-1) dry weight) while the levels of naturally occurring radionuclides, such as (210)Po and (210)Pb, were found to be high in most samples; the highest observed value (27.43 Bq kg(-1) dry weight) for (210)Po being in the red Jania longifurca alga. In addition, most brown alga species were also found to accumulate (210)Po, which indicates their selectivity to this isotope. On the other hand, brown alga (Cystoseira and Sargassum Vulgare) have shown a clear selectivity for some trace metals such as Cr, As, Cu and Co, this selectivity may encourage their use as biomonitor for pollution by trace metals. Moreover, the red alga species were found to contain the highest levels of Mg while the brown alga species were found to concentrate Fe, Mn, Na and K and nonmetals such as Cl, I and Br.  相似文献   

12.
《Environment international》1999,25(2-3):325-334
In the dystrophic Lake Skjervatjern, located at the west coast of Norway, periods with high precipitation coincide with an increase in the concentrations of natural organic matter (NOM) and several trace elements. The lake has no visual inlets, and, during high flow periods, a major part of the drainage follows macropores, entering the lake 10–40 cm below the surface. Water from the lake and the macropores were fractionated according to size by means of a hollow fiber ultra-filtration technique, during two periods with high precipitation. In the macropores, the high molecular weight form of NOM (nominal molecular cut off > 10 kDa) appears to be an important transporting agent for several trace elements that strongly interact with NOM (e.g., Fe, Al, Pb, Sm, La, Ce, and Eu). In contrast, anionic (V and As) and acid sensitive (Mn and Cs) elements were, generally, at a low molecular weight form (nominal molecular cut off < 3 kDa). The latter showed similar or lower concentrations in the macropores compared to the lake water, and NOM were apparently of small importance as a carrier for V, As, Mn, and Cs. Differences in concentration and size distribution of trace elements between the macropores and the lake basins indicate that parts of NOM and associated trace elements that enter the lake in a high molecular weight form, undergo aggregation and gravitational settling and thereby become a part of the lake sediments.  相似文献   

13.
Concentrations of nitrate and trace elements such as arsenic,cadmium,chromium,copper,manganese,nickel,lead,selenium,antimony and mercury in 18 different brands of bottled water were investigated.For comparison,samples of tap and well water from three different places of Tehran were also analyzed.UV/VIS spectrophotometer and Graphite Furnace Atomic Absorption Spectrometer were used for the analysis of nitrate and trace elements,respectively.Results obtained were compared to Iranian,World Health Organization(WHO)and Environmental Protection Agency(EPA)guideline for drinking water.Nitrate concentration in bottled,tap and well water samples were in maximum safe nitrate concentration of Iranian and WHO standards.However,70%of bottled water samples and one sample of tap water were below the standard level proposed by EPA and probably remedial action should be taken.Concentration levels of all analyzed elements investigated in all examined water samples were below the maximum contaminant level prescribed by Iranian,WHO and EPA regulations.  相似文献   

14.
洞庭湖退田还湖区畜牧业资源与环境评估   总被引:2,自引:1,他引:1  
以洞庭湖流域3个选择畜牧业为替代产业的退田还湖示范堤垸为例,以氟、铬、镉、铅、汞和砷为主要检测指标,参照国家标准,分别对示范堤垸内与畜牧业密切相关的水、土壤与饲草饲料的质量进行了评估。结果表明,示范堤垸水环境化学指标除了大肠杆菌群落外,其余基本达到了无公害和绿色食品卫生标准中关于农田灌溉用水和养殖用水的规定;土壤中铬、镉、铅、汞和砷与氟的背景值均低于无公害和绿色食品标准规定的产地土壤环境指标;大部分饲料、饲草原料中氟、铬、镉、铅、汞和砷含量符合无公害或绿色食品卫生标准。示范堤垸水、土和饲料资源的良好环境背景状况为畜牧业向绿色或有机畜牧业方向发展奠定了自然条件与资源的基础。  相似文献   

15.
The aim of the present study was to assess whether the use of pig slurry and associated copper accumulation in calves grazing pastures fertilized with pig slurry from the Deza region in NW Spain has a significant influence on toxic metal and essential metal levels, and to investigate whether copper accumulation is correlated with the levels of these other metals. Correlations between copper, toxic metals (cadmium, lead) and essential metals (molybdenum, iron, zinc, selenium, manganese and cobalt) concentrations were evaluated in liver and kidney of 195 calves from the region of Deza. Metal concentrations were determined by ICP-OES and correlations between pairs of elements by Pearson correlation analysis. There was a strongly significant positive association between copper and lead in the liver. Considering the trace metals, copper in the liver showed significant positive correlations with cobalt in both liver and kidney, and with molybdenum in the liver. In addition, significant correlations were observed between copper and most essential metals in kidney. These associations are similar to those found in different animal species experimentally dosed with copper and other metals, as well as in cattle exposed to normal copper concentrations.  相似文献   

16.
Geochemical specialization of the soil and plant cover has been revealed in the vicinity of the active Karymsky volcano (the eastern coast of the Kamchatka Peninsula), where the concentrations of most trace elements in the soil are lower than their clarkes but those in plants exceed their contents commonly recorded in living matter. Freshly deposited volcanic ash is enriched with movable forms of trace elements. As a result of hypergenic processes, they are dissolved and transferred to ground and surface waters, which accounts for a rich mineral composition of vegetation.  相似文献   

17.
Samples of atmospheric particulate matter obtained from representative areas of the city of Baghdad were collected on glass fiber filters using a high-volume sampler. Atomic absorption techniques were used to analyze the total suspended particulates (TSP) for the following trace metals; Fe, Cu, Zn, Pb, Mn, Cr, Cd, Co, and Hg. Sulfates were measured by turbidemetric method. Ion-selective electrodes was used for chloride analysis. It is concluded that the major components of TSP in the ambient air of Baghdad consist of mineral dust. Pb and Cd gave high enrichment factor values, which implies enrichment of these two metals from anthropogenic sources. High enrichment factors were also obtained for Zn and Cu. It is also concluded that in this arid area, the black smoke reflectance method is not suitable for measuring total suspended matter gravimetrically.  相似文献   

18.
The application of flame atomic absorption (FAAS), electrotehrmal atomic absorption (ETAAS), inductively coupled plasma emission (ICP), and direct-current plasma emission spectrometry (DCP) for the determination of major, minor, and trace elements in Urban Particulates (SRM 1648), Wear Metals in Oil (SRM 1084 and 1085), and Simulated Solid-Waste Leachates is described. Interference were encountered in the determination of the trace elements in SRM 1648 by ETAAS; however, these interferences were alleviated using a 1% solution of ammonium dibasic phosphate as a matrix modifier. The concentration of elements in SRM 1084 and 1085 and the simulated solid-waste leachates were significantly above the detection limits by FAAS or ICP and no analytical difficulty was encountered.  相似文献   

19.
A sequential extraction procedure was applied to identify forms of Ni, Zn, Pb and Cu with Fe- and Mn-oxides associated in alluvial sediments of the River Danube within Pancevo Oil Refinery (Serbia). The five steps of the sequential extraction procedure partitioned metals into: CH(3)COONH(4) extractable (S1); NH(2)OH.HCl carbonate extractable and easily reducible (S2); (NH(4))(2)C(2)O(2)/H(2)C(2)O(2) moderately reducible (S3); H(2)O(2)-HNO(3) organic extractable (S4); and HCl acid soluble residue (S5). Extracted concentrations of trace metals, analyzed after all five steps, were found to be (mg kg(-1)) for Mn: 656, Fe: 26734, Ni: 32.3, Zn: 72.8, Pb: 13.4 and Cu: 27.0. Most of the elements were found in acid soluble residue, characterizing stable compounds in sediments. Non-residual fractions of trace metals (sum of the first four fractions) were analyzed because they are more bioavailable than the residual amount. Correlation analysis and two multivariate analysis methods (principal component and cluster analysis) were used to understand and visualize the associations between the non-residual fractions of trace metals and certain forms, more or less crystalline of Fe- and Mn-oxides within the analyzed sediments, since Fe- and Mn-oxides play an important role in trace metal sorption within aquatic systems, especially within the Danube alluvium where the fluctuations of groundwater are very frequent and the level of groundwater could come close to surface.  相似文献   

20.
This study investigates the distribution of three trace elements (Cd, Cu and Zn) in tissues (exoskeleton, abdominal muscle and hepatopancreas) of two shrimp species (Penaeus merguiensis and Penaeus semisulcatus). Special emphasis in this study was placed on evaluating the effects of storage conditions on redistribution of the elements and moreover the potential roles of metallothionein in tissue redistribution. The specimens were collected from the northern part of Persian Gulf during September 2001 and January 2002. The concentrations of metals in the tissues were measured using an Inductively Coupled Plasma-Atomic Emission Spectrophotometer (ICP-AES) and an ICP-Mass Spectrometer (ICP-MS). Metallothionein levels were determined using Differential pulse polarography. Results show a similar hierarchy for Cd and Cu concentrations among different tissues as follows: hepatopancreas>exoskeleton>muscle; and for Zn, the hepatopancreas again contained the highest levels, though there were not any significant differences in Zn concentrations between muscle and exoskeleton. Significant differences were found between the species in the case of Cd and Zn concentrations. Cd and Zn levels in P. semisulcatus were markedly higher than in P. merguiensis. In general, there were highly significant differences among the storage conditions from accumulation the selected trace elements and metallothionein in both species point of view, but in most cases, no significant differences could be observed among the fresh, refrigerated and frozen specimens of P. semisulcatus. In regards to Zn and Cu accumulation in edible (muscle) tissues of P. merguiensis, optimum conditions for frozen storage is -30 degrees C as ice-frozen, and in terms of short-term storage, 1-day refrigeration is recommended. The redistribution of Zn and Cu during the storage period can be attributed to the role of metallothionein in their transport from organ(s) to muscle during storage. The variations in pH values measured in the muscle of P. merguiensis in different storage conditions showed a similar trend with metallothionein, Zn and Cu. In contrast, it appears that cadmium is transported from muscle to the other tissues. Exoskeleton is probably one of the recipient tissues of cadmium. The inter-elemental relationships were assessed for each species, separately. A significant positive relationship was observed between the concentrations of Zn and metallothionein in P. semisulcatus, whereas in P. merguiensis, Cd concentrations decreased significantly with increasing metallothionein. Highly significant differences between the sexes in Cu and Zn contents could be detected. The differences between the sexes in the levels of Zn and Cu were significantly greater in P. semisulcatus. Highly significant size-related differences were found in the levels of Cd, Cu and metallothionein in the selected tissues of the shrimp species. Comparison between the mean concentrations of the elements in muscle tissue and existing guidelines indicate that in nearly all cases, the concentrations were well below permissible levels for human consumption. The only exception was observed regarding mean values of Cd, which was somewhat greater than some of the recommended levels.  相似文献   

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