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1.
宝鸡城市街尘、土壤及河流沉积物重金属形态迁移特征   总被引:1,自引:0,他引:1  
在宝鸡城市街尘、土壤及河流沉积物基本理化性质和重金属元素含量分析的基础上,重点研究了重金属元素在街尘、土壤及河流沉积物中的赋存形态和迁移特征.结果表明:在街尘中Cu主要以可氧化态和残余态形式存在,Pb主要以可还原态和可氧化态形式存在,Zn和Cd主要以乙酸可提取态形式存在,Mn、Fe、Co、Ni和Cr主要以残余态形式存在...  相似文献   

2.
Eleven metals (Ca, Mg, Fe, Zn, Cu, Mn, Cd, Co, Cr, Ni and Pb) were estimated in hair samples of metal arc welders and a control group with the same socioeconomic background. Nitric acid–perchloric acid wet digestion procedure was adopted for the estimation of endogenous metal contents by ICP-AE technique. The study exhibited the following increasing order of the metal concentrations: Cd??1, dry weight, respectively. On average, the levels of Mn, Ni, Pb and Fe were found to be 1.5–2.4 times higher in the hair of welders compared with controls. Besides age and exposure which were strongly correlated, Cu–Mg, Mn–Mg, Ca–Co and Cd–Zn also showed significantly positive correlations. The identification of metal sources, done by cluster and principal component analyses, revealed four factors: age and exposure; Cu, Mg, Mn and Fe; Ca and Co; Cd, Zn, Ni and Pb. High levels of Fe were found to have a depleting impact on Co levels. The arc welders were feared to accumulate heavy metals in their bodies due to long-term endogenous exposure.  相似文献   

3.
Spectrophotometric methods were used to measure the contents of the polyvalent metals Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Mo and Zn in 16 species of red, brown, and green seaweeds and 2 species of higher water plants collected from the intertidal and sublittoral zones of Vostok Bay, Sea of Japan. Some of the species displayed a unique capability for increased accumulation of groups of several metals. We have termed this ability specific group concentration. Thus, Ptilota filicina concentrates Ti, V, Mn, Fe, Ni, Cu, Zn, and Mo; Polysiphonia japonica Ti, V, Mn, Fe, Zn, Mo, and Cr; Rhodomela larix Ti, V, Mn, Fe, Ni, Zn, and Cr; Agarum cribrosum Ti, V, Mn, Fe, Ni, Zn, and Cr; Ulvaria splendens Ti, V, Mn, Fe, Ni, and Cu; Ulva fenestrata Mn, Fe, Ni, and Cu; Enteromorpha prolifera Mn, Co, Zn, Mo, and Cr; codium yessoensis V, Mn, Fe, Ni, and Cr; Zostera asiatica Ti, Mn, Ni, and Mo; Phyllospadix iwatensis Ti, V, Mn, Fe, and Zn. Specific group concentration makes possible a new approach to the study of active transport of polyvalent metals, physiologically significant for live organisms, through cell membranes, and the study of the formation of complex metal compounds inside the cell, i.e., the study of the processes that determine the degree of element concentration. The contents of the metals studied in sea water and the accumulation coefficients were also determined. The variation range is extremely high both for the seaweed species and metals investigated. Maximum coefficients were noted for Mn: 1.8·105; Ti: 4.4·104; Fe: 2.4·104; Cr: 1.2·106.  相似文献   

4.
5.
芜湖市区土壤重金属污染评价及来源分析   总被引:5,自引:0,他引:5  
对芜湖市区153个土壤样品中9种重金属的含量进行测定和评价,利用多元地统计方法进行污染来源分析。结果表明:芜湖市区土壤Zn、Fe、Mn、Cu、Pb、Co、Cd、Ni、Cr的平均含量分别为96.8、30600.1、466.1、35.0、29.1、16.7、1.2、26.3、78.3mg/kg;除Fe、Mn、Ni外,其他元素均高于相应土壤背景值,Zn、Cu、Pb、Co、Cd、Cr分别是背景值的1.26、1.09、1.17、1.20、6.11、1.29倍,说明这些元素出现了一定程度的积累。单因子评价结果表明Cd污染最为严重,Zn、Cu、Pb、Co和Cr为轻度污染,Fe、Mn和Ni没有污染。综合相关性、聚类及主成分分析可知,Fe和Mn为"自然源因子",不同功能区分布主要受成土母质控制;Zn、Cu、Pb和Cd为"交通及工业活动因子",Cu、Cd高值区均分布在开发区,Zn和Pb的高值区分布在镜湖区;Ni、Co和Cr为"农业活动因子",其空间变异受成土母质及农业活动等因素影响。  相似文献   

6.
Heavy metal concentrations (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn) were determined in various tissues (hepatopancreas, branchial hearts, salivary gland, gills, genital tract, mantle, arms and skin) of Octopus vulgaris collected from three different contaminated sites in front of Alexandria (Egypt) during 2000. All collected tissues displayed high enrichment factors when compared to ambient levels. Heavy metal concentrations in most tissues displayed significant differences among sites, sizes and sex. This study suggests that hepatopancreas, and to a lesser extent branchial hearts, are better indicators of chronic Cu, Fe, Zn and Cd contamination than edible tissues. The enrichment factor (EF) for heavy metals in the hepatopancreas and in edible tissues allowed discriminating our samples into three main groups; (1) EF?>?55 (Cu), (2) EF ranging from 15 to 7.5 (Fe, Cd and Zn) and (3) EF?相似文献   

7.
Airborne particulate matter of up to 10 µm collected at an urban and a rural area at Sarajevo in 2013 and 2014 was acid digested for determination of total concentrations or extracted with synthetic gastric juice for the bioaccessible fractions of Cd, Cr, Cu, Fe, Mn, Ni, Pb, V, and Zn and determined by graphite furnace and flame atomic absorption spectrometry. The total concentrations of Cr, Cu, Fe, Mn, Pb, and V were higher at the urban site, while those of Cd, Ni, and Zn were virtually equal at both sites. The average bioaccessible fractions exhibited the following trend at both sites: Fe > Zn > Cu > Mn > Pb > Cr > V > Ni > Cd. Enrichment factors and daily intake of metals by inhalation were calculated.  相似文献   

8.
The present investigation deals with the accumulation of heavy metals in fields contaminated with fly ash from a thermal power plant and subsequent uptake in different parts of naturally grown plants. Results revealed that in the contaminated site, the mean level of all the metals (Cd, Zn, Cr, Pb, Cu, Ni, Mn and Fe) in soil and different parts (root and shoots) of plant species were found to be significantly (p<0.01) higher than the uncontaminated site. The enrichment factor (EF) of these metals in contaminated soil was found to be in the sequence of Cd (2.33) > Fe (1.88) > Ni (1.58) > Pb (1.42) > Zn (1.31) > Mn (1.27) > Cr (1.11) > Cu (1.10). Whereas, enrichment factor of metals in root and shoot parts, were found to be in the order of Cd (7.56) > Fe (4.75) > Zn (2.79) > Ni (2.22) > Cu (1.69) > Mn (1.53) > Pb (1.31) > Cr (1.02) and Cd (6.06) approximately equal Fe (6.06) > Zn (2.65) > Ni (2.57) > Mn (2.19) > Cu (1.58) > Pb (1.37) > Cr (1.01) respectively. In contaminated site, translocation factor (TF) of metals from root to shoot was found to be in the order of Mn (1.38) > Fe (1.27) > Pb (1.03) > Ni (0.94) > Zn (0.85) > Cd (0.82) > Cr (0.73) and that of the metals Cd with Cr, Cu, Mn, Fe; Cr with Pb, Mn, Fe and Pb with Fe were found to be significantly correlated. The present findings provide us a clue for the selection of plant species, which show natural resistance against toxic metals and are efficient metal accumulators.  相似文献   

9.
南京城市土壤重金属含量及空间分布特征   总被引:13,自引:0,他引:13  
研究了南京城市土壤重金属含量、来源及空间分布特征。结果表明,南京城市土壤中V、Mn、Co、Ni、Cr污染不明显,但受到了不同程度的Cu、Pb、Zn、Sb、Hg、Cd污染,其中Hg污染比较严重。V、Mn、Co、Ni、Cr含量之间均呈极显著正相父;Cu、Pb、Zn、Sb、Hg、Cd含量之间也均呈极显著正相关。南京城市土壤V、Mn、Co、Ni、Cr主要继承了原土物质;Hg、Cd、Pb主要来源于城市燃煤、机动车尾气及工厂排放粉尘;Sb主要来源于机动车尾气和工厂排放粉尘。南京城市土壤Hg、Cd、Pb、Sb含量空间分布规律非常相似,均表现为外围向市中心有逐渐增加的趋势,并且在新街口—鼓楼、梅山硫铁矿形成异常高值的岛状、环状区域。  相似文献   

10.
The speciation of trace metals in surface sediment in Kisumu Carwash area of Winam Gulf, was studied and results compared with those found at Usoma beach which was found to be several orders of magnitude less polluted. High proportions of the metals were bioavailable (fractions 1–6) with BA% ranging from 21.7% (Al) to 94.5% (Pb) at Carwash and 19.6% (Al) to ~100% (for Cd and Pb) at Usoma beach. The readily mobilizable fraction (fractions 1–4) decreased in the order: Pb > Mn > Sn > Cu > Co > Zn > Mg > Cd > Mo > Ni > Cr > Fe > Al at Carwash and Mn > Mo > Sn > Pb > Cd > Mg > Cu > Zn > Co > Ni > Fe > Cr > Al at Usoma beach. The total Zn, Cd, Cr, and Cu sediment concentrations at Carwash were higher than the threshold effect concentrations (TECs), although their bioavailable concentrations were lower than these limits. Both the total and bioavailable concentrations of Pb in surface sediment at Kisumu Carwash area were higher than the TEC threshold limit indicating significant contamination from this heavy metal. Although there was a general good agreement on data obtained by sequential extraction as compared with those obtained by direct aqua-regia digestion, there were large discrepancies for some specific metal analytes which could be accounted for in terms of analytical variations and lack of uniformity in physical and chemical composition of the sediment samples analyzed.  相似文献   

11.
This work presents the results of the determination of concentrations of the trace metals Ni, Zn, Mn, Pb, Cd, Cr, Co, Cu, and Fe in eggs from farms in Southern Nigeria. The mean concentrations (µg?g?1 fresh weight) ranged from 0.6 to 1.2 for Ni, 3.1 to 8.9 for Zn, 0.45 to 0.65 for Mn, 0.4 to 1.2 for Pb, <0.09 to 0.3 for Cr, 0.1 to 0.3 for Cd, 0.26 to 0.34 for Co, 0.9 to 1.2 for Cu and 19.5 to 24.0 for Fe. The concentrations and estimated dietary intakes of these metals were below the respective statutory limits. The Target Hazard Quotient (THQ) values for the individual metals in all zones are less than 1, i.e., within safe levels. The combined THQ values for the different zones were greater than 1but less than 2, with a significant contribution of cobalt.  相似文献   

12.
淮南市城区地表灰尘重金属分布特征及生态风险评价   总被引:5,自引:0,他引:5  
城市地表灰尘中重金属会对人体健康和生态环境产生危害,为研究城市中不同功能区地表灰尘重金属的含量和潜在生态危害水平,以典型煤炭资源型城市淮南市的地表灰尘为研究对象,采集工业区、商业区、交通区、文教区、居住区和公园绿地等6种功能用地共40个点位的地表灰尘。采用电感耦合等离子体发射光谱(ICP-OES)和DMA-80直接测汞仪测定Zn、Pb、Cu、Cr、Cd、Ni、Co、V、Hg的含量,分析其在不同功能区地表灰尘中的分布特征、相关性及可能的来源;并应用潜在生态危害指数法对重金属在不同功能区的潜在生态危害进行评价。结果表明:1)淮南市地表灰尘中 Zn、Pb、Cu、Cr、Cd、Ni、Co、V、Hg的平均质量分数分别是202.59、74.63、62.74、110.69、0.57、35.82、12.18、50.95和0.105 mg·kg-1,其中Zn、Pb、Cu、Cr、Cd、Ni、Hg的平均含量分别是淮南市土壤背景值的3.47、3.17、2.04、1.21、9.50、1.12、2.56倍,是中国土壤背景值的2.73、2.87、2.78、1.81、5.88、1.33、1.62倍。2)9种重金属中,Zn和V的含量在不同功能区分布相对均匀,其他重金属在不同功能区含量均表现出较明显的空间异质性。3)不同功能区中,Zn、Pb、Cu、Ni、Co、V、Hg的平均含量在工业区最高,Cr 和 Cd 的平均含量在交通区最高。4)不同重金属的相关性表明,Zn、Pb、Cu、Cd、Ni 等5种元素有同一来源,Co 和 V 有同一来源。5)单项潜在生态危害系数大小为 Cd〉Hg〉〉Pb〉Cu〉Ni〉Co〉Zn〉Cr〉V。不同功能区9种重金属复合生态危害均处于强生态危害水平(300≤RI〈600),其中工业区和交通区潜在生态危害水平最高。  相似文献   

13.
Elevated concentrations of potentially toxic elements (PTEs) are usually found in areas of intense industrial activity. Thriasio Plain is a plain near Athens, Greece, where most of the heavy industry of the country has been situated for decades, but it also is a residential and horticultural area. We aimed at measuring the levels of PTEs in soils and indigenous plant species and assessing the health risk associated with direct soil ingestion. Samples of soils at roadsides and growing plants were collected from 31 sites of that area. Concentrations of Al, As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, V and Zn were measured in both soils (as pseudo-total) and aerial plant tissues. We found that As, Cd, Cr, Cu, Ni, Pb and Zn were higher than maximum regulatory limits. Element concentrations in plants were rather lower than expected, probably because indigenous plants have developed excluder behaviour over time. Copper and Zn soil-to-plant coefficients were highest among the other elements; for Cu this was unexpected, and probably associated with recent Cu-releasing industrial activity. Risk assessment analysis indicated that As was the element contributing more than 50 % of the health risk related to direct soil ingestion, followed by Cr, Pb, and, surprisingly, Mn. We concluded that in a multi-element contamination situation, elevated risk of PTEs (such as As, Cr and Pb) may reduce the tolerance limits of exposure to less-toxic elements (here, Mn).  相似文献   

14.
The concentrations of 11 heavy metals (Ag, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, V and Zn) were measured in the tissues (digestive gland, branchial hearts, gills, digestive tract, kidney, genital tract, muscle, skin, shell) of the two cephalopods Eledone cirrhosa (d'Orb.) and Sepia officinalis (L.) collected from the French coast of the English Channel in October 1987. The tissues of both species displayed a similar pattern of heavy-metal accumulation: the digestive gland, branchial hearts and kidney were the major sites of concentration for all 11 metals; the digestive gland accumulated silver, cadmium, cobalt, copper, iron, lead and zinc, the branchial hearts high concentrations of copper, nickel and vanadium, and the kidney high concentrations of manganese, nickel and lead. The digestive gland, which constituted 6 to 10% of the whole-animal tissue, contained >80% of the total body burden of Ag, Cd and Co and from 40 to 80% of the total body burden of the other metals. The ratios between heavy metal concentrations in the digestive gland and those in the muscle separated the elements into three groups, those with a ratio 10 (Cr, Mn, Ni, Pb, V, Zn), those with a ratio >10 to <50 (Co, Cu, Fe), and those with a ratio 50 (Ag, Cd). The digestive gland of cephalopods (carnivorous molluscs whose age can be easily calculated with great accuracy) would seem to constitute a good potential indicator of heavy metal concentrations in the marine environment.  相似文献   

15.
An assessment is presented of distribution characteristics of heavy metals in the urban topsoil from the city of Xuzhou. The concentrations of Ag, Al, As, Au, Ba, Be, Bi, Cd, Co, Cr, Cu, Fe, Ga, Hg, Li, Mn, Mo, Ni, Pb, Pd, Pt, Sb, Sc, Se, Sn, V and Zn have been determined from 21 soil samples. Examination of lognormal distribution plots indicates that the diagrams of Al, Be, Fe, Ga, Li, and V are almost linear suggesting that these metals are almost unaffected by anthropogenic activities while the plots for As, Cd, Cu, Pb, Pd, Pt, Se, Zn and others are not linear probably due to anthropogenic activities from which these metals are delivered to the soils. Al is used for mineralogical normalization of these data. An evaluation of background values for topsoil is also carried out by means of lognormal distribution plots. The results show our background values obtained from the lognormal distribution plots are comparable to those values of uncontaminated soils of Xuzhou obtained by previous work except for Cd and Hg. At present, no explanation for the exceptions Cd and Hg can be given.  相似文献   

16.
大气PM2.5中重金属的化学形态分布   总被引:1,自引:0,他引:1  
运用多级连续提取法,对广州市不同季节不同采样高度大气PM2.5中重金属的化学形态和生物有效性进行分析。研究表明,PM2.5中各重金属元素之间的化学形态分布差异较大,Zn、Cd、As、Mn主要分布在F1(可溶态与可交换态)和F2(碳酸盐态、可氧化态与可还原态),绝大部分的Pb以F2存在,Ni和Mo主要分布在F1和F3(有机质、氧化物与硫化物结合态),Cu主要以F2和F3存在,Cr主要分布在F3和F4(残渣态),Co则4种形态平均分布。采样高度对重金属的化学形态分布影响不大,同一采样期内楼顶与地面样品中同一元素的化学形态分布结果比较一致。两个采样季节重金属的形态百分比存在不同程度的变化,2007年春重金属的不稳定态(F1)比例比2006年秋普遍增加,次稳定态(F2、F3)比例减少。在10种重金属中,Cd、Zn、Pb和As的生物有效性系数高(>0.7),属于生物可利用性元素,在环境中的活动性要明显高于其它元素;Mn、Cu、Mo、Co、Ni和Cr元素的生物有效性系数值在0.2~0.6之间,属于潜在生物有效性元素,在环境中比较稳定。  相似文献   

17.
A field study was conducted in an iron mine in Hamedan (Iran) to find native accumulator plants and to evaluate the extent of metal bioaccumulation in the naturally growing vegetation. The concentrations of total As, Cd, Cr, Fe, Mn, Mo, Ni, Pb, Si, and Zn were found to be higher in the mine than in soil. These plants accumulated the highest amounts of the following metals in their roots: Euphorbia cheiradenia As, Stipa barbata Cd, Pb and Cr, Euphorbia macroclada Cu, Centaurea iberica Fe, Reseda lutea Mo, Salvia spinosa Ni and Zn, and Xanthium strumarium Se. In the aerial parts, the highest metal accumulation was found in Epilobium fragilis As, Carthamus oxyacantha Cd, Fe, Mn, and Pb, Verbascum speciosum Cu, Centaurea iberica Mo, Salvia spinosa Ni and Cr, Glaucium grandiflorum Se, and Malva neglecta Zn. Enrichment factors and bioconcentration factors were also determined; C. oxyacantha, S. spinosa, M. neglecta, C. iberica, V. speciosum, G. grandiflorum, and E. fragilis are the most effective accumulators and are proposed for phytoremediation of polluted soils.  相似文献   

18.
Nine potentially harmful heavy metals (Cd, Co, Cr, Cu, Hg, Mn, Pb, Ni, and Zn) were measured in 477 topsoil samples collected from urban–rural areas in the city of Wuhan in order to identify their concentrations and possible sources, and characterize their spatial variability for risk assessment. Results showed that in most rural areas heavy-metal concentrations in soil were similar to their natural background values, but Cd, Cu, Hg, Pb, and Zn concentrations were relatively higher in densely populated districts and around industrial facilities. Multivariate analyses (correlation matrix, principal component analysis, and cluster analysis) indicated that Cd, Cu, Hg, Pb, and Zn were mainly derived from anthropogenic inputs, and Co, Cr, and Mn were controlled by natural source, whereas Ni appeared to be affected by both anthropogenic and natural sources. The result of risk assessment indicated that nearly 48% of the study area suffered from moderate to severe contamination.  相似文献   

19.
以东莞市5个镇区为研究对象,采集电镀企业周边大气样品,分析了样品中重金属(包括As、Co、Cd、Cr、Cu、Mn、Ni、Pb、Sb、V、Zn和Hg)的含量分布,使用富集因子(enrich factor)、地累积指数(index of geoaccumulation)、Hakanson法和美国国家环境保护局(US EPA)的人体暴露健康风险评价模型,对PM_(2.5)、PM_(10)、总悬浮颗粒物(TSP)中重金属进行人体健康风险评价。结果表明,PM_(2.5)、PM_(10)和TSP中As、Cd和Cr平均浓度皆超标。Cr、Ni和V元素在3种颗粒物中非富集,主要为自然源;As、Co、Cu、Pb和Zn,可能来源于自然源和叠加的工业污染。Cd、Hg和Sb浓度受人为污染影响严重。Cd、Sb、Cu、Zn、Pb为生物可利用元素(K>0.6),在环境中的可迁移性高且易于被生物体和人体吸收。Mn元素的非致癌风险值较其他重金属要高1~4个数量级,且儿童的非致癌暴露风险值HQ均高于成人的。3种颗粒物中重金属元素通过呼吸吸入途径产生的非致癌风险HI值均高于人体可接受的上限1.0,其主要贡献来源于Mn的影响,研究区非致癌风险较为严重。除PM_(10)中Co元素和TSP中Co、Cr的成人致癌风险CR值大于10-4之外,其余大部分重金属元素通过呼吸途径产生的致癌风险CR值均在可接受范围之内,此外,3种颗粒物中的成人的致癌暴露风险值CRT均高于儿童的CRT值,并且除了PM_(2.5)中儿童的重金属致癌暴露风险CRT值(4.70E-05)低于人体可接受范围的上限(10-4),其余CRT值均高于10-4,致癌风险较为严重。  相似文献   

20.
A car and a railway coach with an InterCityExpress interior were combusted in a tunnel. The deposition of pollutants could be detected by passive sampling devices over the distance of several hundred meters. Cotton passive collectors were analyzed for the elements Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Sb, Sn, V and Zn. A comparison with analytical results of PCDD/F and PAH (US EPA) showed a close similarity between the concentration profiles of some elements and the organic pollutants. As one outcome, Cd, Cu, Pb, Sb, Sn and Zn could be used as indicators for the estimation of surface contamination with PCDD/F or PAH in the event of such fires, thereby providing the advantages of faster results and lower costs.  相似文献   

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