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1.
The research shows that in the Celje area (Slovenia), the historical anthropogenical emissions are 1,712 tons of Zn and 9.1 tons of Cd. For Zn, this value represents approximately 0.3% of the total Zn production in that area. Close to the former zinc smelting plant, the “Zn precipitation” has been estimated to be up to 0.036 mm. The 100-year Zn production left behind a heavily contaminated area with maximum concentrations of Zn of up to 5.6% in attic dust and 0.85% in the soil, and 456 mg/kg of Cd in attic dust and 59.1 mg/kg in the soil. The calculation of historical emissions is based on the data of heavy metals concentration in the attic dust at 98 sampling points and on the data from 19 measurement sites of the weight of total monthly air deposit. The main idea behind determining past emissions is that when the weight of the deposited dust on a small area is multiplied by the concentration of the element in that area, the mass of the polluter which has been transported to the place of interest by air can be calculated. If we sum up all the weight over the whole geochemical anomaly, we get the quantity of historical emissions.  相似文献   

2.
This study aimed to (1) investigate microrubbers (MRs) for the first time and identify microplastics (MPs) in street dust, (2) determine the physicochemical and mineralogical characteristics and morphology of dust particles, (3) understand the concentration and the possible source(s) of heavy metals/metalloids, (4) identify the chemical speciation and mobility potential of trace metals in urban street dusts, and (5) determine adverse health effects of street dust on children and adults living in the city of Bushehr in southwestern Iran. Generally, twenty four street dust samples were collected and analyzed. Calculated enrichment factors indicate high levels of contamination. Statistical analysis reveals that the two main sources of trace elements include road traffic emissions (Cu, Zn, Sb, Hg, Pb, Mo) and re-suspended soil particles (Al, Mn, Ni, Ti, Cd, Co). BCR sequential extraction results indicated that As, Zn, Cu, and Pb mainly occur in the exchangeable fraction and hence are highly bioavailable. X-ray powder diffraction analysis revealed the presence of calcite, dolomite, quartz, and magnetite. The size distribution of dust particles was also investigated using a scanning electron microscope (SEM), while elemental distribution was analyzed using an attached energy dispersive X-ray spectrometer (SEM–EDS) unit. Dust particles from heavy traffic areas are much finer compared with other investigated areas. MPs and MRs, mostly fibers and fragments, were detected in all samples [ranging from 210 to 1658 (MPs) and 44 to 782 (MRs) items/10 g dust] using fluorescence microscopy. The hazard index for As is higher than 10?4 for children and adults indicative of high risk. According to the calculated potential ecological risk index, Hg indicated moderate ecological risk in the street dust of the study area.  相似文献   

3.
解析大气总悬浮颗粒物(TSP)的重金属来源可为重金属生态风险评价和环境修复提供理论依据。本文研究了中国南方某工业城市冶炼厂周边冬季TSP和表层土壤(0~20 cm)中的重金属环境效应。采用大气主动采样技术收集TSP样品,原子荧光光谱法和电感耦合等离子体质谱法测定其中重金属的含量,结合富集因子法和Pearson系数法分析重金属含量特征及其来源。结果表明,研究区TSP中Zn、Pb、Cd含量最高达到30809.06×10-6、9902.91×10-6、1011.21×10-6,分别是中国土壤背景值的201.43、222.53、5616.20倍,属于污染严重级别;Ni、Cr含量分别是中国土壤背景值的1.83倍和2.96倍。冶炼厂、火力发电厂和化工厂等人为源是Zn、Pb、Cd、Hg、As等重金属富集的主导因素;土壤重金属含量与TSP重金属含量呈显著正相关,可判定研究区土壤的重金属来源主要为大气沉降。  相似文献   

4.
Concentrations of As, Ba, Co, Cr, Cu, Mn, Ni, Pb, V, and Zn in campus dust from kindergartens and elementary schools in Xi’an, China, were analyzed using X-ray fluorescence spectrometry and heavy metal contamination levels were assessed based on the geoaccumulation index (I geo), enrichment factor (EF) and numero synthesis pollution index (NSPI). The results indicate that, in comparison with Shaanxi soil, dust samples have elevated metal concentrations as a whole, except for V, Mn, Ni, and As. The assessment results of I geo and EF indicate that V, Mn, Ni, and As in campus dust are uncontaminated, while Ba and Cr are uncontaminated to moderately contaminated, and Co, Cu, Pb, and Zn are moderately to strongly contaminated. The NSPI results show that most dust samples presented heavily contaminated by heavy metals. More attention should be paid to heavy metal contamination of campus dust from kindergartens and elementary schools of Xi’an.  相似文献   

5.
The aim of this research was to determine how fast the level of heavy metal concentrations in the air decreases in relation to increasing distance from the source of pollution and what the influence area is of the zinc smelting plant which existed for 100 years in Celje. In that period it produced approximately 580,000 tons of raw Zn from sphalerite ore by the pyrometallurgical process. The production left behind a heavily contaminated area, where the concentrations of Pb and Zn in the soil can be expressed as a percentage. A model has been made on the basis of the data of concentrations of Zn and Cd in the soil and attic dust regarding the distance and direction from the source of the pollution. Because Celje lies in a basin we chose a linear model, which describes the decreasing of the concentrations of Zn and Cd only in one direction. Sampling has been conducted on the four river valleys which stretch from the source of the pollution in all four directions: north, west, south and east, up to 13 km from the source. The power function with a negative exponent was used. With the solution to the calculated functions according to the distance, we can estimate the theoretical distance when the concentrations drop to the natural background level. The range of influence of the zinc smelting plant has been estimated to be between 14 and 52 km for the presence of anthropogenic Zn in attic dust and between 9 and 14 km for the presence of anthropogenic Zn in the soil, depending on the direction from the plant. Correlations between the measured values and the ones from the model are high: from 0.75 up to 0.98.  相似文献   

6.
山东省小清河沿岸土壤重金属污染分布及迁移规律   总被引:4,自引:0,他引:4       下载免费PDF全文
通过对山东省小清河流域土壤重金属污染现状的调查研究,查明土壤重金属污染状况,元素来源和分布迁移规律,从而为该区土壤重金属污染的科学治理提供有效依据。研究发现,小清河沿岸地区的重金属污染主要表现为As、Cd、Cr、Ni等元素的污染;依据内梅罗污染指数评价方法发现研究区存在重金属污染的土壤总面积为880.5 km2,未受到重金属污染的土壤面积为1 822.1 km2,分别占全区总土壤面积的32.58%和67.42%,其中上游的济南市城区北园镇至华山镇区域的小清河两岸是重污染区。对小清河流域土壤重金属来源的探析表明,大气干湿沉降是土壤重金属污染的主要来源;土壤重金属的生物有效性评价显示重金属元素Cd的活动态比例高达56.17%,活化迁移能力强,是该区对生态环境危害性最大的污染因子。此外,As、Cd、Cr、Pb等重金属元素的活动态含量明显受pH值和Corg含量的制约,在低pH值、高Corg含量的土壤区应高度重视As和Cd的污染问题。  相似文献   

7.
刘睿  黄艺  王丽  李祥  赵浩任 《矿物岩石》2019,39(3):111-119
以攀枝花市为研究区域,分别采用富集因子法、潜在生态危害系数法和单因子指数-内梅罗综合污染指数法有针对性地对土壤和近地表大气尘中As,Cd,Cr,Cu,V,Zn和Ni七种重金属污染状况进行了综合性评价。结果表明,攀枝花宝鼎煤矿区和攀钢片区土壤及近地表大气尘中的重金属含量较高,均超过四川省土壤背景值。富集因子指数分析表明,研究区重金属污染受到人为活动的影响较大,污染也较为严重,其中Zn和Cd的富集情况较为显著,Cd,V,Zn,Cu为主要污染因子。潜在生态危害系数结果表明,在各元素中,绝大多数元素处于轻微生态危害,Cd 8个点位处于强生态危害,7个点位处于很强生态危害,处于中等生态危害的占5%,处于强生态危害的占47%,处于很强生态危害的占41%,土壤中Cd元素的潜在生态危险最高,其余元素处于轻微生态危险状态。单因子指数-内梅罗综合污染指数分析结果表明,Cd,Cr和Ni元素在宝鼎煤矿区和攀钢片区都存在重度污染,Cd(7.70),Cr(3.38),Cu(4.49),V(3.62),Zn(3.68)和Ni(5.80)存在重度污染,As(2.07)存在中度污染。  相似文献   

8.
Urban street dust is one of important indicators of the status of urban environmental pollution. There are many studies in capital cities, but little attention has been paid to this kind of study in medium cities, especially in China. The dust samples were collected in the district of traffic crossroads in Xianyang city, Shaanxi Province. Pb, Cd, Cu, Ni, Zn, Cr and Mn concentrations were determined by using atomic absorption spectrometry. The results indicate that street dusts in Xianyang city have elevated metal concentrations as a whole in comparison with Shaanxi Province soil, except for Mn. The content of heavy metals was comparable to those in capital cities. Correlation coefficient analysis, principal component analysis and cluster analysis were used and three main sources were identified; Mn comes mainly from soil sources; Cu, Zn and Ni are mainly derived from industrial sources combined with traffic sources; Pb, Cr and Cd have traffic sources. Heavy metal enrichment factors were calculated, which can reflect human influence degree of street dusts.  相似文献   

9.
The purpose of this study was to examine the influence of parent sediment material on soil geochemistry and to locate possible pollution sources in the area of Turku town in southwestern Finland. The study area is glaciated terrain and subsurface samples were chosen to represent five different parent sediment materials: glacial till, glaciofluvial or littoral sand, clay, peat and marine mud. Elemental concentrations of surface (100 samples) and background soil (50 samples) were analysed by ICP-AES (Al, Ba, Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, S, Sr, Ti, V) and by graphite furnace AAS (As, Cd, Mo, Se). Loss-on-ignition was determined as an indicator of organic matter. Analytical results were examined using multivariate statistical methods. The results indicate that the studied soils are not heavily contaminated; there were only few sample sites with elevated heavy metal concentrations. High Pb concentrations were observed along main traffic routes, and also in places where there has been small-scale use of antifouling paints. However, concentrations of heavy metals in topsoil were in general significantly lower than those measured in large cities elsewhere. The parent material strongly affects the geochemical character of the soils. Clays naturally have a significantly higher concentration of heavy metals than sands or till material. This is also reflected in concentrations in organic topsoil. When assessing target levels for polluted soil, the primary sediment appears to be a more important factor than the amount of organic matter.  相似文献   

10.
Heavy metals are introduced in human tissue through breathing air, food chain and human skin. They can cause damage to the nervous system and internal organs. In the present study, sixty street dust samples were collected from the central area of Tehran and were digested in the laboratory to determine the content of Zn, Ni, Cd, Cr, Cu and Pb, using inductively coupled plasma optical emission spectrometry (ICP-OES). The level of contamination with the analyzed metals was determined according to the following indices: geo-accumulation index (I geo), enrichment factor (EF), pollution index (PI), integrated pollution index (IPI) and potential ecological risk index (RI). The average concentration of heavy metals found was in the order of Zn > Cu > Pb > Ni > Cr > Cd. The average I geo values for Cd, Cr, Cu, Ni, Pb and Zn were 1.53, ?1.88, 2.68, ?0.67, 1.62 and 2.70, respectively. Among the investigated heavy metals, zinc and copper had the maximum average EF values and were placed into the “very severe enrichment” class. Potential ecological risk factor (E r) also indicated that Cd had the highest risk, and it was classified as of considerable potential ecological risk. Therefore, it is necessary to pay more attention to the appearance of Cd in the human environment. The calculated potential ecological risk index values also illustrated that the street dust samples presented a “moderate ecological risk.” The calculated IPI values showed that the pollution levels of the street dust samples ranged from high to extremely high.  相似文献   

11.
为了评价有色金属矿山城市大气降尘中重金属元素的污染状况、来源及其对土壤重金属累积的影响,分析测试了铜陵市大气降尘样品中Cd元素的含量.分析结果表明,降尘样品中Cd元素的平均含量为16.44/μg/g,明显高于安徽省江淮流域多目标调查中铜陵土壤Cd元素的平均含量;降尘中Cd元素含量较高的样品出现在矿山和冶炼厂附近.用富集...  相似文献   

12.
In order to assess the pollution levels of selected heavy metals, 45 bottom sediment samples were collected from Al-Kharrar lagoon in central western Saudi Arabia. The concentrations of the heavy metals were recorded using inductively coupled plasma-mass spectrometer (ICP-MS). The results showed that the concentrations of Pb and Cd exceeded the environmental background values. However, the heavy metal contents were less than the threshold effect level (TEL) limit. The concentrations of heavy metals in lagoon bottom sediments varied spatially, but their variations showed similar trends. Elevated levels of metals were observed in the northern and southern parts of the lagoon. Evaluation of contamination levels by the sediment quality guidelines (SQG) of the US-EPA revealed that sediments were non-polluted-moderately to heavily polluted with Pb; non-polluted to moderately polluted with Cu; and non-polluted with Mn, Zn, Cd, and Cr. The geoaccumulation index showed that lagoon sediments were unpolluted with Cd, Mn, Fe, Hg, Mo, and Se; unpolluted to moderately polluted with Zn and Co; and moderately polluted with Pb, Cr, Cu, and As. The high enrichment factor values for Pb, As, Cu, Cr, Co, and Zn (>2) indicate their anthropogenic sources, whereas the remaining elements were of natural origins consistent with their low enrichment levels. The values of CF indicate that the bottom sediments of Al-Kharrar lagoon are moderately contaminated with Mn and Pb.  相似文献   

13.
The method of principal component analysis was applied to systematical research on the soil multi-media environment, including soil, surface water, ground water, waterbody sediment and agricultural crops, as well as pollution-inducing wastewater, mullock (or waste ore) and slag in the periphery of a large-sized Pb-Zn mining and smelting plant in a karst area of Guangxi Zhuang Autonomous Region. The results revealed that soils in the area studied have been heavily polluted by Cd, Zn, Pb and Hg, and the levels of these metals in the samples of agricultural crop greatly exceed the standards. The above-mentioned pollutants exist in all soil-multi-media environments. The mullock, slag, wastewater, surface water, ground water, soil, and agricultural crops constitute a composite ecological chain. Therefore, the improper disposal of mullock and slag, and the use of polluted wastewater for agricultural irrigation are the main causes of soil pollution. Heavy metals in the soil have three transition progresses: point (improved soil with slag, ground water inflow plot), linear (river transition) and non-point transition (regional pollution by slag) patterns, and the tailing yard is the most important locus for heavy metals to release into the environment.  相似文献   

14.
Hydrochemical monitoring and heavy metal speciation by sequential extraction techniques indicate direct relationships among enrichment of the heavy metals (copper, lead, zinc, iron, manganese, and cadmium), soil acidification, and salinization in Kedron Brook floodplain area of Brisbane, Australia. Assessment of modes of occurrence and distribution pattern of the heavy metals in soil, sediment, and water environments of this coastal plain indicates that the total concentrations and reactive fractions of these metals are elevated in soil and channel bed sediments. Such geochemical signatures reflect the complex influence of sources and a combination of natural and anthropogenic processes on concentration and dispersion within the coastal zone. According to a working model presented, the enrichment of the heavy metals, like cadmium, in the soil and sediment profiles is triggered by capillary pumping during low groundwater standing levels, when the metals are in a stable form associated with dry gels. During higher groundwater levels and occasional flood events, these metals become mobilized when the gel material is transformed into soluble colloidal phase.This study indicates that the potential impacts of heavy metal pollution on the coastal ecosystems can not be assessed and managed in isolation solely by considering the natural cause-effect relationships. The complex nature of sediment-soil-water interactions in the coastal hydrodynamic zones can produce a manifold of effects, including mobilization, concentration, and/or dispersion of heavy metals at both short and longer time scales. In the case of Kedron Brook, chemical erosion due to variation in natural climatic and hydrodynamic conditions contributes significantly to concentration of heavy metals in the coastal environments. Therefore, a sound understanding of the prevailing hydrogeochemical processes is essential for prediction of the fate of heavy metals and establishment of meaningful coastal zone management strategies.  相似文献   

15.
南京栖霞山铅锌矿区铅同位素示踪   总被引:3,自引:0,他引:3  
南京栖霞山铅锌矿已开采50余年,环境问题日益突出。为了了解污染来源和污染传播方式,采集了该地水、土、植物、大气沉降、燃油灰尘、矿石、人血和生物等多种样品进行重金属元素含量和铅同位素示踪分析。结果表明矿区重金属污染严重,且污染随着靠近矿区而逐渐加重,重金属元素Pb、As、Cd、Cu、Zn之间相关性明显,初步反映了污染与矿山有关;同位素分析显示,矿区大气沉降样品、大部分植物样品、部分土壤和部分生物样品铅同位素组成与矿石铅同位素组成相似,证实了污染源为矿山。另外,大气沉降与植物样品铅含量高且它们的铅同位素组成相当,反映了大气沉降是污染传播方式之一。  相似文献   

16.
武汉市墨水湖沉积物重金属污染特征与防治对策   总被引:8,自引:2,他引:8  
苏春利  王焰新 《矿物岩石》2006,26(2):111-116
武汉市墨水湖重金属污染严重,其污染特征在我国城市湖泊中具代表性。在对墨水湖不同湖区沉积物中重金属污染物空间分布特征进行分析的基础上,应用地积累指数法探讨不同重金属元素含量随深度变化的规律和原因,并对墨水湖沉积物中重金属的污染程度进行评价表明:墨水湖沉积物中重金属元素锌和汞污染最为严重,污染程度由高到低依次为:Zn>Hg>Cu>C r>Pb>A s;从整个湖区来看,分布有排污口的周边湖区污染严重,湖心污染程度较低;沉积物中主要重金属元素含量随深度增加而降低,其变化规律主要受污染状况的影响,沉积物颗粒粒径的变化和早期成岩作用的影响不大。为了改善墨水湖水质条件和重金属污染严重的现状,必须在截污、疏浚和引水工程等基本治理措施保护下,重建和恢复沉水植物系统,才能从根本上改善湖泊水质。  相似文献   

17.
Spatial and temporal distribution of heavy metals (Chromium, Copper, Nickel, Lead, and Zinc) in the sediment of Longgan Lake, middle reaches of Yangtze River, China were analyzed to discuss their enrichment characteristics and history in combination with geochronological data and to identify anthropogenic effects. The results showed that the enrichment state of heavy metals was higher in the western versus eastern lake area, although their concentrations behave in the opposite case, which demonstrated that stronger human activities existed in the western lake catchment. The enrichment history of heavy metals pointed out that prior to 1950, the enrichment state was lower in the ambient lake areas illustrating the natural effect on the lake; thereafter the human activities in the catchment enhanced markedly causing an increasing heavy metal enrichment. The increase of heavy metal enrichment in the 1970s occurred in the central lake areas. The temporal difference between the ambient and central areas elucidated that the heavy metal accumulation might be buffered by the lake before they entered the sediment. Correlation analysis revealed that there was a significant correlation between heavy metals in the sediment suggesting their similar sources. Heavy metals were distinctly related to aluminum, calcium, lithium, iron, and organic matters, which could denote their forms in the sediment.  相似文献   

18.
《Applied Geochemistry》2001,16(11-12):1361-1368
Due to rapid urbanisation and scarcity of land, most of the urban parks and recreational areas in Hong Kong are built close to major roads or industrial areas, where they are subject to many potential pollution sources, including vehicle exhaust and industrial emissions. An extensive soil survey was conducted in urban parks of Hong Kong to study the current conditions of heavy metals contamination in soils. Soil samples and associated street dusts were collected from more than 60 parks and public amenity areas in old urban districts, industrial areas and New Towns of the territory. Soils were also sampled in the remote country parks to establish the baseline conditions. The total concentrations of heavy metals and major elements in the samples were determined. The results indicate that urban soils in Hong Kong have elevated concentrations of Cd, Cu, Pb and Zn. The parks with high metal concentrations are located in old urban commercial districts and industrial areas, indicating that the major contamination sources in these soils are traffic emissions and industrial activities. In addition, the application of Cd containing phosphate fertilizers may be an important source of Cd in urban park soils. The street dusts have highly elevated Zn concentration, particularly along the main trunk roads. The high Zn content in the street dusts may come from traffic sources, especially vehicle tyres. Selective soil and road dust samples were also analysed for potential chemical speciation by a sequential chemical extraction method. The chemical partitioning results show that Pb and Zn are mainly in the carbonate/adsorbed and Fe–Mn oxide phases, while Cu is largely associated with the organic and sulphide fractions. The high exchangeable Cd in urban soils and high concentration of Zn in street dusts need further investigation for their ecological and health implications.  相似文献   

19.
Mining and smelting activities are the main causes for the increasing pollution of heavy metals in soil, Water body and stream sediment. An environmental geochemical investiga-tion was carried out in and around the Panzhihua mining and smelting area to determine the ex-tent of chemical contamination in soil and sediment. The main objective of this study was to in-vestigate the environmental geochemistry of Ti, V, Cr, Mn, Cu, Pb, Zn and As in soil andsediment and to assess the degree of pollution in the study area. The data of heavy metal con-centrations reveal that soils and sediments in the area have been slightly contaminated. Geo-chemical maps of Igeo of each heavy metal show that the contaminated sites are located in V-Ti-magnetite sloping and smelting, gangues dam. The pollution sources of the selected elementscome mainly from dusts resultant from mining activities and other three-waste-effluents. The areaneeds to be monitored regularly for trace metal, especially heavy metal enrichment.  相似文献   

20.
太湖沉积物微量元素特征和变化:自然与人类活动的影响   总被引:7,自引:1,他引:7  
通过对太湖沉积物微量元素的测定,分析了沉积物的元素含量特征及变化趋势,指出了重金属元素的分布特点。沉积物和岩石微量元素的上地壳标准化值显示,它们的曲线存在明显的区别,反映了物质在风化和沉积过程中不同的性质差异。重金属在太湖北部地区较高,在南部地区较低,特别是As、Hg、Cu、Zn、Ni。对照背景值,探讨了重金属元素的富集程度,并运用地累积指数评估了沉积物的污染程度。根据1987年和2000年的数据,计算了重金属的累积速率。最后,讨论了自然作用和人类活动对微量元素的影响。  相似文献   

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