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1.
The concentrations of 37 trace elements (Ag, Ba, Be, Cd, Ce, Co, Cr, Cs, Cu, Dy, Er, Ga, Gd, Ge, La, Li, Mo, Nb, Nd, Ni, Pb, Pr, Rb, Sb, Sm, Sn, Sr, Tb, Th, Tl, U, V, W, Y, Yb, Zn and Zr) were determined by ICP-MS in surface soils and plants (Sida rhombifolia) sampled around a lead smelter in Lastenia, Province of Tucuman, NW Argentina. Soil and plant patterns of Pb, Cd, Ag, Zn and Cu demonstrate the effects of pollutant dispersion plumes following the prevalent wind directions. The high element concentrations observed, especially Pb (>5,000 mg/kg), could cause serious environmental problems in areas of close proximity to the smelter. Consequently, measures to assess potential consequences for the local population should be considered to determine if measures to protect the environment are necessary.  相似文献   

2.
This study attempted to investigate whether increased hair lead concentrations due to environmental exposure are accompanied by parallel increases in blood lead concentrations. A sample set consisting of both occupationally-exposed individuals and persons from the general population was investigated. The lead content of scalp and pubic hair from the general population (n=189), traffic police personnel (n=27) and battery workers (n=22) were analysed. The hair samples were taken from the nape of the neck by cutting 23 cm closest to the scalp and cleaned using a washing procedure developed in our laboratory. The effectiveness of the washing procedure was partly determined by examining the scanning electron micrographs of the hair samples. Venous samples of blood were taken from each volunteer's arm.The traffic police and battery plant operators sampled had significantly higher average scalp hair and pubic hair lead levels than the non occupationally-exposed general population. No significant differences were found between the blood lead values of these workers and the general population. Compared to the general population both occupationally-exposed groups had significantly more symptoms of lead toxicity.Lead particles were still observed on the hair shafts after the washing procedure. The amount of such lead contamination was difficult to quantify, the problem being further exacerbated by the difference in hair texture of the persons sampled. This exogenous contamination therefore detracts from the usefulness of hair as an indicator of lead exposure.  相似文献   

3.
The background levels of lead in Jamaica in soils and sediments, estimated at 37 mg kg–1, are relatively high compared with world averages. Several areas have values in excess of this due to mineralisation and pollution. One such is the residential Hope Flats/Kintyre area in which levels of lead up to 2.5% are found in the soils and up to 8 g kg–1 in the water of the nearby Hope River. The blood lead levels of a sample of children were in the range 5.7–57 g dl–1. The high lead levels suggest a potential health risk, particularly for the children. This can be minimised by programmes which include community education, case management and abatement to reduce the lead exposure.  相似文献   

4.
研究了湖南省郴县东坡铅锌矿自然扩散晕内重金属的污染特征及污染控制措施,结果表明,该区域内的环境污染是以Pb、Zn、Cd和As为主的多金属复合污染,污染物在土壤中的化学形态以残渣态为主,水体中的细微尾矿砂颗粒物是重金属的主要迁移载体。该区域内作物中的Pb、Cd残留很高,用改变耕种制度的方法来控制铅锌矿区内的重金属污染是有效的  相似文献   

5.
Two primary lead smelters and one secondary lead smelter have been active in the Socorro, New Mexico (USA) area in the last 110 years: the Billing smelter from 1883 to 1894, the Cuba Road smelter from 1881 to 1900, and Cal West from 1979 to 1984. Samples of plants and surface soil under each plant from all three sites were analysed for lead. The plants consisted of sparse grasses, cacti, creosote bush, snakeweed, mesquite and fourwing saltbush. Lead levels in the plants increased (2-440 g g–1) as the lead in the alkaline soils (25-10000 ng g–1) increased. However, the BAC (biological absorption coefficient), which is the ratio of lead content in the plant to the lead content in the soil, a measure of relative accumulation, decreased by one to two orders of magnitude, except for grasses and snakeweed. At background lead levels, there was little difference between lead in rootsversus foliage. At high lead levels, there was higher lead in roots versus foliage at the Billing and Cuba Road sites. The reverse was noted at Cal West. Because this is a recent operation, the higher lead in foliage may be due to foliar uptake. Plant growth at all sites appeared healthy.  相似文献   

6.
汽油无铅化与环境空气中铅污染的变化趋势   总被引:4,自引:0,他引:4  
文章简要分析了 1 998年天津市环境空气及交通环境空气中铅污染的程度。机动车尾气排放是环境空气及交通环境空气中铅污染的重要来源 ,1 998年机动车推广使用无铅汽油后天津市铅污染状况明显减轻。  相似文献   

7.
成都市河道表层沉积物(淤泥)铅污染特征   总被引:5,自引:0,他引:5  
文章分析了成都市河道(沙河、府河、南河)表层沉积物淤泥铅含量特及铅同位素丰度比的测定数据,结果表明铅含量变化范围是21.1~279 mg/kg,平均值为65.3 mg/kg,中值55.2 mg/kg,统计标准差65.03,变异系数为0.996,说明河道表层沉积物含量变化大。端元物质的铅同位素组成特征是燃煤的放射成因铅高于燃油,可以示踪和鉴别成都市环境铅的污染来源。三河淤泥铅同位素组成均大多落在崔家店热电厂降尘和华能热电厂燃煤飞灰的范围,沙河、府河有少数几个样品点落在燃煤铅(崔家店热电厂燃煤降尘)和柴油铅之间,其铅的来源可能是两者的混合。  相似文献   

8.
Levels of Pb, Zn, Cu, Cr, Ni and Cd were determined in topsoil and vegetation in the vicinity of a factory manufacturing lead- batteries in Ibadan, Nigeria. The samples were collected along five transects in different directions, and varying distances up to 1000m from the factory. Soil lead levels were found to be elevated around the factory, with average levels of about 2000mgkg–1 close to the fence that declined gradually to about 50mgkg–1 some 750m away. Soil-lead level around a primary school located about 500m from the factory was as high as 1450mgkg–1. Lead levels were equally elevated in the vegetation, though average levels in vegetation were slightly lower than in the soil. Cadmium concentrations in soil and vegetation, though low, were more positively correlated with lead levels than any of the other metals are with lead.  相似文献   

9.
A river embankment sediment beneath a road bridge in South Australia had been surveyed on a previous occasion to a depth of 10 cm and found to contain high levels of copper, lead and zinc deposited during previous lead and zinc-based primer paint stripping operations prior to repainting the bridge. Since the river embankment is geologically different from the surrounding non-embankment soils, and a sufficient distance from the bridge along the river embankment could not be traversed, the geological background Cu, Pb and Zn fraction was established initially using a solid phase sequential extraction (SPSE) procedure. Assessment of the degree of contamination and extent of vertical mobility was then established. Copper was a minor contaminant and present predominantly as the geological background species. Lead was partitioned evenly between the oxalate soluble fraction and residual fraction to a depth of 30 cm with a decrease in total Pb concentration from 497 to 141 mg Pb kg–1 while Zn was predominantly in the oxalate soluble fraction to a depth of 15cm with a decrease in concentration from 1013 to 150 mg Zn kg–1. The reduced rate of nitrification and the lower total concentration of NO3 -N together with the higher respiratory quotient, combined with the lower microbial quotient, are indicative of microbial stress due to heavy metal toxicity. In the case of Pb and Zn paint stripping residues, these changes in indicators of microbial health are possibly the result of the greater abundance and hence possible bioavailabilty of organo- and chloro-Pb compared to organo- and chloro-Zn complexes.  相似文献   

10.
The content and distribution of the lead in coal, gangue and the sulfur ball and the pyritic gangue of the Permo-Carboniferous in the North China Plate have been systematically studied (nearly 300 samples) in this paper. The Permo-Carboniferous coals in the North China Plate account for nearly 44.45 of total Chinese coal resources, and most of the steam coals in China come from the Permo-Carboniferous coals in the North China Plate. The result shows that lead content in the coal varied from 1.45 to 63.60 mg kg–1, averaging 23.95 mg kg–1; the lead content of the sulfur ball and the pyritic gangue in the coal seam ranges from 70.26–1060 mg kg–1, with an average of 271.28 mg kg–1; the lead content of the gangue is from 29.5 to 77.81 mg kg–1, averaging at 40.77 mg kg–1. The lead in the coal seam is mainly concentrated in the pyrite, such as sulfur ball, pyritic gangue or pyrite, and is the least concentrated in the organic of coal. The content of the lead has a direct ratio with the ash and the pyretic sulfur. Coal washing can reduce the content of the pyretic sulfur and the lead.  相似文献   

11.
The Old Lead Belt of Missouri was a major lead-producing region for over a century. Several large tailings piles and other industrial wastes remain behind, though mining operations in the region ceased in 1972. Samples of stream sediments and fish were collected from established sites on the Big River and Flat River Creek over a 3-year period from 1998 to 2000 to evaluate ongoing remediation efforts and determine the current impact of residual mining wastes. Benthic sediments and fish taken in the vicinity of inactive industrial sites were found to contain elevated concentrations of Pb, Zn, Cu, and Cd. Concentrations of Pb and Zn in fillets of suckers and sunfish, as well as in whole bodies of sunfish, correlate well with metal concentrations observed in surficial sediments. The results of analyses provide valuable quantitative information regarding specific sources, current levels of contamination, potential risk to public health, and will allow more accurate assessment of continuing remediation efforts.  相似文献   

12.
Lead contamination in the roadside soils of Slovenia   总被引:5,自引:0,他引:5  
The level of lead contamination along the roadway Ljubljana to Zagreb was established in 184 soil samples. The samples were taken from two depths (0–5cm and 15–20cm) and at different distances from the roadway. The influence of terrain morphology, prevailing winds, geological parent material and type of vegetation was estimated. Heavy traffic is confirmed as main source of lead contamination (average enrichment factor 17) in soils. The highest lead accumulation is localised in the top soil layer and within 10m from the roadside. Contamination with lead is more pronounced in soil samples from cuttings and slopes than in soils from plains and mounds. Soils derived from carbonate rocks contain higher lead concentration than those derived from other parent material.  相似文献   

13.
This study tests the hypothesis that exterior sources of lead dust are more important than interior sources in the route of exposure of children. Benign field methods were used to distinguish between potential and actual lead exposure problems. Utilising hand wipe and surface wipe techniques, hand and environmental samples were obtained from selected day care centres at different locations within New Orleans. Previous research has shown that soil lead is determined by location within the city. Private and public day care centres were selected from inner and outer city areas to estimate the extent of hand lead exposure. To measure and identify the extent of environmental lead exposure, hand wipes were taken before and after playing outdoors. Results of preliminary findings show that outdoor lead dust is a more potent contaminant of hands than indoor lead dust. An association was found between the amount of lead on children's hands after playing outdoors and the lead content in the exterior dust and soil. Although two girls out of forty children had exceptionally high hand lead quantities after playing outdoors, in general, boys have higher hand lead levels than girls. The private inner-city day care centre had a severe contamination problem in its outdoor play area. By contrast, the outdoor play area of the public inner city day care centre is of such a high quality that the quantity of lead dust is independent of location in the city.  相似文献   

14.
利用盆栽试验,研究在砖红壤上添加不同浓度的铅对花生作物的生长和残留的影响,从农产品卫生质量和作物效应两方面出发,提出花生作物的铅参考临界含量.  相似文献   

15.
Currently, attention has shifted to chronic or subclinical disorders attributed to lead (Pb) exposure. The aim of this study was to determine delta-aminolevulinic acid (δ-ALA) levels in urine of Angooran Lead &; Zinc Company workers. This cross-sectional study was conducted on 170 workers, in which 24 h urinary samples were collected and δ-ALA levels were measured spectrophotometrically. Questionnaire forms were completed indicating age, location, and duration of work. The mean δ-ALA level in urine was 5.44 mg L?1. δ-ALA levels were correlated with age, location, and duration of work in the company. The mean δ-ALA level in the urine of workers was in the upper limit of normal ranges. δ-ALA level in urine may not be the best discriminating factor of Pb exposure from the baseline to the high levels, but is recommended as a regular and routine test for all Pb-exposed workers in addition to the measurement of Pb in blood for subjects with higher δ-ALA levels.  相似文献   

16.
外来植物紫茎泽兰(Eupatorium adenophorum)入侵我国西南地区并造成了严重的生态灾难,通过研究Pb、Cd及其复合污染对紫茎泽兰生长及吸收富集特征的影响,有助于从生态学角度为紫茎泽兰的综合防控提供依据。采用模拟Pb、Cd污染土壤培养法研究了不同浓度Pb、Cd及其复合污染作用下紫茎泽兰的生长响应及重金属吸收、富集和迁移特征变化。结果表明:低浓度的Pb、Cd对紫茎泽兰的生长有促进作用,高浓度则表现出一定的抑制作用,生物量,株高,根长均明显减少。紫茎泽兰体内Pb、Cd吸收量与污染土壤具有良好的相关性,随处理浓度增加明显增大,极端浓度Pb、Cd胁迫下紫茎泽兰各器官Pb、Cd积累量与对照相比显著增加,1000 mg·kg-1处理时紫茎泽兰根、茎、叶的Pb质量分数均分别高达603.69、568.31、598.85 mg·kg-1;100 mg·kg-1 Cd处理时其根、茎、叶的Pb、Cd累积量依次为165.21、93.59、152.79 mg·kg-1。说明紫茎泽兰对Pb、Cd具有较好吸收累积及转运能力,可作为重金属污染地区的一种理想的修复植物。  相似文献   

17.
通过室内盆栽试验研究了中、低浓度铅(Pb)和苯并[a]芘(B[a]p)复合污染在土壤-植物系统中的归宿规律和相互影响,以考查Pb-B[a]p复合污染的相互作用.采用4因素6水平均匀设计试验方案,w(Pb)范围为0~1 120 mg·kg^-1,w(B[a]p)范围为0~6.4 mg·kg^-1.结果表明,在非根际环境中,Pb的不同结合态未受到B[a]p的影响,而土壤中B[a]p的自然降解过程也未受到Pb的影响;在黑麦草根际环境中,Pb的可交换态和碳酸盐结合态以及Fe/Mn氧化物结合态含量与非根际土壤相比明显降低,有机物和硫化物结合态含量明显升高,这与黑麦草根际分泌物和植物根际的吸收作用有关;玉米和黑麦草地上部和根部Pb含量均与土壤中Pb总量之间呈显著正相关关系,与B[a]p含量间不存在显著相关性;在玉米和黑麦草根际环境中,B[a]p的降解速率比非根际土壤有明显提高,其中黑麦草的促降解作用强于玉米;Pb对玉米和黑麦草根际土壤中B[a]p的降解过程具有一定的抑制作用,这与根际环境对Pb的活化作用进而增加Pb对微生物有效性有关;Pb对植物根部吸附B[a]p的过程也有一定影响.总体而言,在根际和非根际条件下B[a]p与Pb的共存均未影响Pb的归宿,在非根际环境中Pb也未影响B[a]p的归宿,但在根际环境中Pb抑制了B[a]p在土壤中的降解及植物根部对B[a]p的吸收.  相似文献   

18.
为了解日益增加的城市土壤铅(Pb)胁迫对城市园林地被植物的影响,采用盆栽实验研究土壤Pb胁迫对藿香蓟(Ageratum conyzoides)叶片生理特性的影响.结果显示,Pb胁迫处理降低了藿香蓟叶片的叶绿素总量及叶绿素a和b含量,质膜透性增大,丙二醛(MDA)含量上升.随着Pb浓度增加,同一时期内藿香蓟叶片SOD、POD和CAT酶活性均上升,但土壤Pb浓度超过750 mg kg-1或1 000 mg kg-1后保护酶活性开始逐渐下降.随着胁迫处理时间的延长,SOD活性在d 20、d 40和d 60时都高于胁迫处理d 7时的活性,POD活性是在d 20时急剧下降,CAT活性则在胁迫处理d 60时急剧下降.研究表明,藿香蓟能在一定程度上适应土壤Pb胁迫,但Pb胁迫浓度超过750 mg kg-1后将影响其生理代谢过程.图4参20  相似文献   

19.
探讨了用异丙醇做溶剂,用火焰原子吸收法测定汽油中铅的方法,实验证明,此方法的回收率在95.5%~104%之间,变异系数在1.38%~2.55%之间,此方法省时,准确,降低实验成本,简化实验步骤,减少实验室污染。  相似文献   

20.
Settled particulate matter was collected in three heavily travelled roadway tunnels (Trinidad, Paraiso and El Valle) to be characterised in terms of lead concentration and composition of organic compounds. Atomic Emission Spectrometry with Inductively Coupled Plasma and Gas Chromatography–Mass Spectrometry (GC–MS) were employed to isolate and identify Pb in acid extracts, and organic compounds in hexane and hexane-dichloromethane extracts. The results for lead analysis reveal that the total concentration present in each tunnel ranges from 5500 to 1260gg–1. This figure indicates a relatively low concentration of lead for settled particles, compared with those reported for suspended particles in this kind of environment, which suggests the lead fractionating between settled and suspended particles in the Caracas Valley area. Thermogravimetric analysis shows the presence of total carbon (total organic carbon + carbonate), to be between 10% and 20% of the total sample. Of this total carbon, 55% is under carbonate (calcite) form and 45% as organic carbon, mostly in the form of tire residues. A fraction of this organic carbon (1%) is soluble in organic solvent (hexane-dichloromethane). The analysis of saturated hydrocarbons showed a similar distribution pattern for each sample. The n-alkane, terpane and sterane compounds, closely resemble those present in gasoline and lubricant additives. The aromatic fraction also displays very similar patterns for polycyclic aromatic hydrocarbons constituted by alkyl dibenzothiophene, phenanthrene, pyrene and chrysene. The distribution of polyaromatic hydrocarbons (PAHs) in the samples was found to be very similar to those in the diesel fuel used by heavy truck vehicles.  相似文献   

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