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1.
The concentrations of Hg, Cu, Pb, Zn, Cd, Fe, Mn, Cr and As were measured in groundwaters from the Upper West and Upper East Regions and the Accra Plains of Ghana. Apart from Fe, the trace metal levels for the two Upper Regions were similar. Samples from the Accra Plains had the highest trace metal concentration. However, Hg and As were undetected in all the samples. While the mean Cd, Mn and Cu concentrations for all the 3 study areas fell below the WHO limit, values for Pb and Cr exceeded the WHO limits for drinking water. Iron exceeded the limits in the Upper West Region and the Accra Plains. Overall, the most abundant elements in groundwaters were Zn, Fe and Cr.  相似文献   

2.
以三江源区玉树县和玛多县为研究区,利用实验室测定的As、Cu、Pb、Zn、Cr、Cd、Hg元素含量和室内采集的土壤原始光谱及其4种转换形式,建立了光谱指标与重金属含量的多元回归模型,利用决定系数(R2)、相对分析误差(RPD)及均方根误差(RMSE)评价模型的精度。研究结果表明,土壤As、Cu、Pb、Zn、Cr、Cd含量与SOM、Fe、Mn、Al、Mg等元素具有显著相关关系,Hg元素则未达到显著性水平。As、Cu、Pb、Zn、Cr和Cd元素估算模型回归方程R2达到了0.5以上,均通过了显著性检验,其中Pb、Zn和Cr元素验证样本RPD均达到了1.4以上,模型具备粗略估算能力;As、Cu和Cd元素验证样本RPD均低于1.4,模型不具备粗略估算能力。Hg元素估算模型回归方程的R2为0.28,未能通过显著性检验,无法用于对Hg含量的估算。  相似文献   

3.
Heavy metal inputs to Mississippi Delta sediments   总被引：1，自引：0，他引：1  
Heavy metal concentrations were determined in suspended particulates, filtered water and sediment collected in the Mississippi River and from its marine delta. More than 90% of the metal load of the river is associated with particulate matter, which is relatively constant in chemical composition with time and place. The Mississippi River suspended material is similar to average crystal rocks in Fe, Al, V, Cr, Cu, Co, Mn, and Ni concentration but is generally enriched in Zn, Cd and Pb. Sediment cores dated by the Pb 210 method show that the Cd and Pb enrichments are recent phenomenon and are most likely due to the activities of man. About 6000 tonne of Pb and 300 tonne of Cd are being added to the delta sediments by man each year, more than 30 times the amount added to the Southern California Bight. River particulate matter is essentially identical to deltaic sediments in Al, Fe, Cr, V, Cd and Pb concentration, but the sediments are depleted in Co, Cu, Mn, Ni and Zn by 20 to 40%. Chemical leaching of the solids show the metal losses to be primarily from the oxide phase, suggesting diagenetic reduction and mobilization as a mechanism. Trace metal concentrations in filtered Mississippi River water were below the limits for safe drinking water and were similar to world average river values. The abundant river suspended matter and high pH combine to keep dissolved trace metal concentrations low.  相似文献   

4.
Street sediment collected in Sault Ste. Marie, Ontario was examined for trace element composition (As, Cd, Cr, Cu, Fe, Pb, Hg, Ni and Zn) and the metal partitioning to various sediment properties was determined by sequential extraction. Total Ni, Cu, Zn and Pb concentrations exceeded the lowest effect levels specified in the Ontario Provincial Sediment Quality Guidelines for Metals (Environment Ontario, 1992) and derived from bioassay studies. According to these Guidelines, the disposal of such sediment has to be guided by environmental considerations. A significant fraction of these metals was extractable in 0.5 N HCl over a 12-hour period and considered as potentially bioavailable. The major accumulative phases of toxic metals in this sediment are exchangeable, carbonate, Fe/Mn oxides and organic matter but the relative importance of each phase varied for individual metals. Approximately 20% of the total extractable Cd is found in each of these four fractions. Pb, Zn and Mn are predominantly bound to carbonates, Fe/Mn oxides and organic matter. Cu shows a high affinity for organic matter and to a lesser extent for carbonates. Elevated levels of Cd, Pb, Cu, Zn, Mn and Cr in the exchangeable and/or soluble phase suggest that sediment associated metals, mobilised from streets in Sault Ste. Marie during runoff and snowmelt, would adversely impact water quality in the receiving waters. However, large fractions of the total metal load are associated with coarser particles which are unlikely to be transported through the drainage system into receiving waters.  相似文献   

5.
Twenty-three metallic elements, including almost all essential and toxic metals such as lead, cadmium, mercury, arsenic, silver, and thallium, have been quantified in 35 types of bottled and canned Polish beer by using double-focusing sector field inductively coupled plasma mass spectrometry (ICP-MS) with ultrasonic nebulization. The samples were digested using concentrated HNO3 in closed PTFE vessels and applying microwave energy under pressure. The means and medians of the concentrations of Rb, Mn, and Fe were on the order of 200 ng/mL; Cu, Zn, V, Cr, Sn, As, Pb, and Ni were detected at 1-5 ng/mL; Ag, Ga, Cd, Co, Cs, Hg, U, and Sb were found at < 1 ng/mL; and In, Tl, Bi, and Th were present at < 0.1 ng/mL. The concentrations of Hg, Cd, As, Pb, and Zn were 1-3 orders of magnitude lower than proposed tolerance limits. The interdependences among determined trace elements were examined using the principal component analysis (PCA) method. The PCA model explained 74% of the total variance. The metals tend to cluster together (As, Tl, Cs, Sn, Th, Bi, and Hg; Cd and Co; Cs and Cr; Fe and Zn; Mn and V).  相似文献   

6.
A multiple chemical tracer approach was used in an effort to account for the atmospheric Hg deposition measured throughout Florida as part of the Florida Atmospheric Mercury (FAMS) Study. Samples of bulk deposition and wet-only deposition were analyzed for a suite of major ions and trace elements in addition to Hg. Significant correlations were found between three groups of elements: Al, Mn, and Fe; Ni, Cu, Zn, and Cd; and As, V, and Pb. However, Hg did not correlate strongly with any of the other chemical tracers. Annual bulk deposition fluxes are attributed to sea-salt aerosols (Na, Cl), the delivery of Saharan dust (Al and Fe), the supply of anthropogenic pollutant aerosols (V, Ni, Cu, Zn, As, Cd, Pb), acidic aerosols (nitrate and nss-sulfate), and an unidentified source for Hg.  相似文献   

7.
Total content of Fe, Mn, Zn, Cu, Pb, Cd, Ni and Co in soils irrigated with sewage effluent increased with increasing years of using sewage effluent in irrigation. Iron and Co applied to the soil from sewage effluent were immobilized mainly in unavailable form; Pb, Cd, and Ni in moderately available form; and Mn, Zn, and Cu in highly available form. The concentrations of Fe, Mn, Zn and Cu in tops of alfalfa and leaves of corn grown on these soils increased substantially with increased levels of available metal content of the soil, while those of other metals were little affected. As for orange, continuous increase in leaves metal content with time was found for Fe, Mn, Zn, Co and Cd. The concentrations of Cd, Co, Ni and Pb in corn grains and orange fruits were several times higher than normal, and this reduces their suitability for human consumption.  相似文献   

8.
Purpose

Heavy metals are among the most common environmental pollutants, which can be introduced into coastal areas from natural and anthropogenic sources, and thereby possibly impact marine organisms and human population. Therefore, the aim of this study was to evaluate the pollution level of Montenegrin coastal sediments by determining the concentrations of 10 metals and metalloids (Fe, Mn, Zn, Cu, Ni, Pb, Cr, Cd, As, and Hg) during one whole decade.

Materials and methods

Sediment samples were collected from 11 sites along the Montenegrin coast during the 2005–2016 exposure to different levels and sources of anthropogenic impact. The extent of pollution was estimated by determining total element concentrations in the sediment. Mineralized samples were analyzed for Cu, Ni, Fe, Mn, Cr, As, Pb, Zn, Cd, and Hg. Pollution status was evaluated using the contamination factor, pollution load index, and geo-accumulation index, as well as statistical methods, such as Pearson correlation coefficient (r) and cluster analysis (CA).

Results and discussion

This study showed that concentrations of individual metals at some locations were extremely high. The metal concentrations (in mg kg?1) ranged as follows: Fe 1995–45,498; Mn 135–1139; Zn 10–1596; Cu 3.8–2719; Ni 2.94–267; Pb 0.1–755; Cr 2.5–369; Cd 0.1–5.4; As 0.1–39.1; and Hg 0.01–14.2. The calculated concentration factor and pollution load index indicates enrichment by either natural processes or anthropogenic influences. The geo-accumulation index value (Igeo) showed that one location was strongly or extremely polluted (3.78?<?Igeo ≤?6.15) with Hg in all investigated years, while extreme Igeo values for four bioactive elements, Pb, Cd, Cu, and Zn, were found in only a few single samples.

Conclusions

On the basis of the obtained values, it can be concluded that generally higher metal contents were distributed in Boka Kotorska Bay sites, although some extreme values were also recorded at the locations outside of the Bay. Geo-accumulation index and pollution load index showed that the metal levels were high enough to pose risk to the ecosystem.

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9.
Recently, Sancti Petri channel on the southwestern (SW) part of Iberian Peninsula has been experiencing urban, industrial, and vehicular expansion. Until recently, there have been only few published reports documenting the pattern of metal accumulation in this estuarine sediment. In the present study, trace metals such as Cu, Zn, Ni, Mn, Pb, Co, Cd, As, and Hg concentrations were analyzed from 69 sediment samples collected from 23 sampling sites of the Santi Petri channel. The magnitude of trace metal accumulation found as the following trend: Mn > Zn > Cu > Pb > Ni > Co > As > Cd > Hg. Spatial distribution pattern demonstrated overall decreasing trend of trace metal from Cadiz Bay mouth to the open ocean mouth, clearly correlative to the presence of anthropogenic inputs. Results of the principle component analysis (PCA) revealed that sediment metal chemistry of Sancti Petri channel is mainly regulated by the concentrations of Pb, Cu, Zn, and Ni; possible sources of those were from vehicular-related emissions. Pollution load index (PLI) and geo-accumulation index (I geo ) indicated overall low values. The study will stimulate improvement of our understanding regarding the pattern of accumulation of metals in the coastal sediments, and the recorded values of metals in the present study can be used as suitable reference for future studies.  相似文献   

10.
The concentration of some trace metals, like Fe, Mn, Cu, Pb, Zn, Co, Cr and Ni, was measured in the potable water of Cuttack City,India during winter, summer and rain events in the course of a two year period. Apart from Fe, all other trace metals fell well within the maximum permissible limit set by WHO for drinking water. On the basis of spatial/temporal variations, weathering of rocks and anthropogenic input were found to be main sources of trace elements in the ground water. The considerable temporal changes indicate that a majority of trace metals is entering the aquifer during rain fall.Factor analysis of the trace element data suggest that Fe, Mn and Cr are interrelated with each other and derived significantly from the aquifer, whereas input of Pb and Co may be due to atmospheric deposition in the study area.  相似文献   

11.
The techniques of diffusional equilibrium in thin films (DET) and diffusional gradients in thin films (DGT) were used to obtain high resolution pore water profiles of total dissolved and labile trace (mobilizable) metals in the sediments of the Rupel River, Belgium. DGT measures labile metal species in situ by immobilizing them on a resin gel after diffusion through a diffusive gel whereas for DET an equilibrium is established between the DET gel and the pore water. Concentrations of Pb and Zn obtained by DGT were in good agreement with the results obtained by centrifugation, and thus were well buffered by rapid equilibrium with the solid phase, whereas Fe, Mn and Cd were very tightly bound to the sediment phase and large differences were observed between the labile and the total metal concentrations. Cu, Zn, Co and Ni show intermediated behavior. Good correlations were found between the profiles of As and Fe and Mn and Co for DET as well as DGT showing a close link between the geochemical behavior of these elements. Cu, Zn, Pb and Cd are also influenced by the reductive mobilization of Fe and Mn oxides but are also closely linked to the bacterial degradation of organic matter in the surface sediments as to the precipitation of metal sulfides in the deeper layers.  相似文献   

12.
Wet Deposition of Trace Metals in Singapore   总被引：3，自引：0，他引：3  
The concentrations of 12 trace metals (Al, Cd, Cr, Cu, Co, Fe,Mn, Ni, Pb, Zn, V, and Ti) in wet depositions are reported. Eighty four rainwater samples were collected using an automated wet-only sampler in Singapore for one year (2000) and subjected to chemical analysis using ICP-MS. Based on the volume-weighted meanconcentrations measured, the trace metals were classified into three groups: Al and Fe with an average concentration of largerthan 15 μg L-1, Cr, Cu, Mn, Ni, Pb, Zn, V, and Ti withconcentrations between 1 and 10 μg L-1, and finally Co and Cd with concentrations lower than 1 μg L-1. Elementenrichment factors were calculated to distinguish between naturaland anthropogenic sources. The calculation of crustal enrichmentfactors with Al as the reference element indicated that while Ti,Fe and Mn originated from crustal sources, the remaining trace metals (Cd, Cr, Co, Cu, Ni, Pb, Zn and V) were mainly derived from anthropogenic sources. The removal of the trace metals from the atmosphere by precipitation was influenced by the rainfall amount as well as pH. The magnitude of the measured average annual wet deposition fluxes of Al, Fe, and combustion-generatedelements such as V, Ni, and Cu is higher than that reportedfor other sites outside Singapore, owing to abundant rainfallthroughout the year in this region.  相似文献   

13.

Drinking water samples were collected from different parts of Cambay and were analyzed for alkali metals and trace heavy metals, viz. Na, K, Cu, Zn, Ni, Mn, Co, Pb, Cd, Mg, and Fe. The Pb and Cd concentration was found eight and four times, respectively, greater than the maximum allowable limits. The pH, COD and BOD values are reported.

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14.
太原市污灌区土壤重金属污染现状评价   总被引：1，自引：0，他引：1  
对太原市污灌区土壤重金属分布特征进行了分析评价,结果表明重金属Pb、Zn、Cu、Ni、Mn、Cr、As、Hg、Cd含量均值均未超过土壤环境质量标准（GB15618—1995）,但其平均值均显著高于太原市土壤背景值。各重金属间的相关分析表明,Pb、Zn、Cu、Ni、Mn、Cr、As、Cd之间呈极显著相关,说明这8种元素污染源可能相同。Hg是本区表层土壤重金属污染的主要因子,重金属元素的污染程度依次为Hg〉Cd〉Pb〉As〉Cu〉Zn〉Cr〉Mn〉Ni。土壤重金属单项污染指数均值均大于1,综合污染指数为2.81,总体上,污染水平为中度及其以上。各种重金属单因子污染指数和综合指数在研究区有相似的空间分布格局,总体分布趋势为东南部小店地区和中南部晋源区相对较高,南部清徐县相对较小;通过因子分析并结合污灌区污染源调查,表明Hg除受污水灌溉的影响外,燃煤释放的Hg可能是重要来源之一,Cd、Zn、Pb和Cu可能来自污水灌溉和大气沉降,以污水灌溉的贡献为主,Ni、Mn、As、Cr来自污水灌溉。Hg、Cd是太原市污灌区土壤中需要优先控制的重金属。  相似文献   

15.
采煤沉陷区土壤重金属含量对土壤酶活性的影响   总被引：1，自引：1，他引：1  
为探明煤矿沉陷区土壤受重金属污染情况,探讨重金属含量对酶活性的影响,以焦作韩王煤矿沉陷区为例,通过野外调查与采样和室内分析,研究煤矿沉陷区土壤中重金属累积特性与土壤酶活性的变化。结果表明:研究区土壤中重金属Cu、Zn、As、Mo、Hg、Pb、Cd等含量均高于对照小区的含量,且有明显的空间异质性;沉陷区各种酶活性大都低于对照点,其在空间分布上受重金属的影响,重金属Co、Ni对大多数酶有促进作用,As、Mo则对酶活性有抑制作用,重金属对酶活性的影响取决于重金属的类型与含量;在研究区,蔗糖酶对重金属污染较为敏感,表明蔗糖酶可作为评估煤矿沉陷区土壤环境质量变化的有效指标。  相似文献   

16.
The objective of this study was to investigate changes of total concentrations and various extract-defined Al and heavy metal fractions in Slovak agricultural soils during the last 25 years. We compared 7 stored soil samples collected between 1966 and 1970 with samples collected in 1994 at the same sites. Seven fractions of Al, Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn were determined with a sequential extraction procedure in all samples. Total concentrations of Cd, Zn, Mn, Ni, and Cu were lower in the 1994 samples; those of Al, Fe, Pb, and Cr were higher. Based on the initial concentrations, the average total concentration changes were: Cd(-10,3%)<Zn(-7,2%)<Mn(-4,8%)<Ni(-2,3%)<Cu(-1,4%)<Al(+2,1%)<Fe(+2,9%)<Cr(+7,4%)<Pb(+8,3%). This row is consistent with the decrease in metal mobility. The differences in salt-extractable metals showed the same pattern; however, changes were more pronounced than for total concentrations. The results suggest that decreases during the last 25 years are caused by higher leaching than deposition rates and increases vice versa. The highest increase in Cr and Pb concentrations is observed in the EDTA-extractable fraction, which mainly characterizes organically bound metals.  相似文献   

17.
Samples of surface and gutter sediment from roads within N.W. London have been analyzed for levels of Cd, Cu, Fe, Mn, Pb, and Zn. Sediment and associated metal grading curves are presented and apart from Mn and Fe which reflect natural background levels, the remaining metals show distributions which relate to road type and traffic conditions. For highways carrying the highest traffic densities the concentrations of Cd and Pb are greatest for grain sizes between 100 and 500 µm and an aggregation process is postulated. Residential side street samples show a marked affinity of Cd, Fe, and Zn for the coarsest grain fractions. Laboratory sorption and desorption studies are described and solution concentrations are obtained for Cd, Cu, Mn, Pb, and Zn over 1 to 30 day time periods. Solubility curves are typically variable with time. The relationship of leachate patterns to particle size and sample site location is discussed and its relative importance to Stormwater loadings is considered. Extraction efficiencies for the five metals are found to be independent of road type and in the order Cd > Zn, Cu > Mn > Pb. The relevance of this hierarchy to Stormwater toxicity is discussed.  相似文献   

18.
浙江省重点地区猪粪中重金属含量及安全施用评估   总被引：5，自引：1，他引：4  
【目的】 浙江的规模养殖集中度高,畜禽排泄物资源化利用率达96%以上,通过堆肥和制作有机肥还田是主要的消纳途径,因此粪便中的重金属含量影响土壤安全及作物的生长。饲料是猪粪重金属最主要的来源,因此,本研究检测了浙江省猪饲料和排泄物中的重金属,为作物施用的安全性评价提供基础数据。 【方法】 采集35家不同规模养殖场的仔猪、生长猪和育肥猪3个阶段饲喂的饲料和粪便样本共566个,采用干灰化法、高压消解法消解,用AAS、AFS、ICP-MS法分析了铁、铜、锰、锌、砷、铅、铬、镉和汞9种重金属含量。 【结果】 1) 粪便中8种重金属平均含量趋势为Zn > Cu > Mn > As > Cr > Pb > Cd > Hg,主要残留元素为Zn、Cu、Mn和As,按干物质计其平均值分别为2405、1288、528和28.2 mg/kg,变异系数 ( CV) 分别为83%、34%、6%和15%。猪粪中Cr、Pb、Cd元素含量较低,在0.29～3.52 mg/kg之间,Hg含量仅3.97 μg/kg。猪粪中重金属含量仔猪阶段趋高,育肥猪阶段趋低,各个阶段变异都较大,变异系数CV值介于21%～112%之间,显示各地的生猪饲养中微量元素添加还比较混乱。2) 饲料有机砷的使用存在明显区域差异,萧山地区占72.7%的饲料样本在各阶段猪饲料中均添加有机砷,衢州地区的占33.3%,两个地区各有1家养殖场未使用有机砷。猪粪中54.9%样本砷含量 > 15 mg/kg,16.9%样本砷含量 > 50 mg/kg,2.8%的粪便砷超过70 mg/kg。3) 按畜禽粪便安全使用准则进行判定,69.9%猪粪铜超标,16.9%猪粪砷超标。按有机肥料标准进行判定,猪粪中54.9%样本砷含量超标。按照饲料中金属元素在粪便中的浓缩率:Fe、Zn、Cu为7～10倍,锰约为3倍,当前饲养水平下,Fe、Zn、Cu元素存在过量添加。4) 以浙江全省旱地单位面积承载量估算,当前能消纳猪粪中Zn、Cu的排放,但当每公顷猪粪施用量超过2.27 t (干计) 时,局部地区重金属就有累积风险。 【结论】 应降低猪饲料中微量元素的添加量,禁止饲用有机砷制剂,才能有效降低猪粪施用所导致的重金属污染;按照目前监测猪粪肥重金属元素含量水平,有机肥的施用量用应控制在2.27 t/hm2 (干基) 以内,以防止对土壤造成污染。   相似文献   

19.
Forty-six surface sediment samples taken along the beds of boththe Jordan and Yarmouk Rivers were analysed for Pb, Cd, Zn, Fe andHg by atomic absorption spectrophotometer. Extraction techniqueswere used to establish the association of the total concentrations of Pb, Cd, Zn and Fe in the sediment samples withtheir contents in the exchangeable, carbonate, Fe/Mn oxides, organic and residual fractions.In the sediments of the Jordan River the recorded heavy metalsconcentrations were as follow: 8.1 ppm for Pb, 0.63 ppm for Cd, 20.3 ppm for Zn, 6 ppm for Hg and 1265.6 ppm for Fe; whereas in the sediment of Yarmouk River were 8.4 ppm for Pb, 0.67 ppm for Cd, 26.4 ppm for Zn, 6.2 ppm for Hg and 1370 ppmfor Fe. Pb, Cd, Zn, and Fe concentrations in the sediments ofboth rivers reflect the natural background value in shale, whereas Hg is moderately enriched. I-geo (geo-accumulation index) of metals in the sediments under study indicates thatthey are uncontaminated with Pb, Zn and Fe; contaminated tomoderately contaminated with Cd; and strongly contaminated with Hg. Heavy metal content in the sediments were found to be significantly influenced by different physico-chemical parameters. The effect of these physico-chemical parameters canbe arranged in the following order: clay fraction > organicmatter fractions > carbonate fraction > silt fraction. As sequential extraction procedure shows that the total concentration of the heavy metals are largely bound to the residual phase (retained 79.5% of Pb, 38% of Cd, 54.4% of Zn and 51.6% of Fe in Jordan River Sediments; and 88.6% of Pb, 48.2% of Cd, 37.6% of Zn and 59.5% of Fe in the YarmoukRiver sediments). The following sequence of mobility are suggested: Fe > Cd > Zn > Pb in Jordan River sediments, and Fe > Zn > Cd > Pb. in Yarmouk River sediments.  相似文献   

20.
Heavy metal distribution and balances of typical forest soils out of German and Danish till The total contents of Cd, Cu, Fe, Mn, Pb and Zn were determined in different horizons as well as in clay coatings, mottles and concretions from 4 Orthic and Gleyic Luvisols around the Baltic Sea. Profile balances resulted in very small losses of Fe, small losses of Cu, Pb and Zn but higher losses of Cd and Mn. All elements were translocated by clay migration but corresponding enrichments in the B-horizons were covered by translocations in soluble form. Only Fe and Mn had been enriched in mottles of the water logged soils.  相似文献   

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