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1.
A five-step sequential extraction technique was used to determine the chemical association of heavy metals (Pb, Zn, Cu and Cd), with major sedimentary phases (exchangeable, surface oxide and carbonate, Fe and Mn oxides, organic and residual metal ions), in samples from floodplain and recent flood sediments of the River Aire, West Yorkshire. Analysis indicates that metals Pb and Zn are primarily associated with the Fe and Mn oxides, Cu with the organic fraction and Cd with exchangeable and surface oxide and carbonate metal ions. Knowledge of the chemical speciation of heavy metals in river sediment, despite the procedure's inherent limitations, facilitates an understanding of their bioavailability, storage and remobilisation in floodplain and river channel environments.  相似文献   

2.
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   

3.
The waste water showed high values of total solid (TS), hardness and chloride with slightly alkaline pH along with high concentrations of Cr (2.03 mg l(-1)), Ni (1.59 mg l(-1)) and Zn (0.46 mg l(-1)). The concentration of Cu (0.21 mg l(-1)) and Zn in industrial waste water was low than Ni and Cr. The diluted (25 and 50%), undiluted (100%) waste water was used to irrigate the lettuce plants grown in alluvial soils. Plants accumulated heavy metals in their shoot (Ni, 13.65; Cr, 19.73; Zn, 21.6 and Cu 14.76 microg g(-1) dry weight) and root (Ni, 41.4; Cr, 31.6; Zn, 30.2 and Cu 15.85 microg g(-1) dry weight) in high concentrations after irrigation with undiluted industrial waste water. Maximum accumulation of heavy metals was found in the root than the shoot (13.65-21.60 microg g(-1) dry weight). Dry matter yield and biomolecules (Chlorophyll a, b and sugar contents) was found to increase with increase in concentration of waste water up to 50%, which declined at the exposure of undiluted waste water. Catalase activity was found to increase with increase in waste water concentrations up to 100%, while carotenoids content increased in plants only up to the 50% waste water irrigation. Use of industrial waste water in such form, on agricultural lands is not found suitable without proper treatment. It could be injurious to plants growth and may be a potential threat to food web.  相似文献   

4.
Metal concentrations were determined in water, sediment, and freshwater fish samples (Squalus cephalus, Barbus esocinus, and Barbus xanthopterus) collected from Karakaya Dam Lake, Turkey, to estimate the risk of human consumption and pollution. Metal concentrations differed between the species (p??Zn?=?Cu in water and Fe?>?Zn?>?Mn?>?Ni?>?Cu in sediment. In general, the accumulation order of elements in the tissues all of the species sampled were found as Fe?>?Zn?>?Se?>?Mn?>?Cu?>?Ni?>?Cd in muscle, Zn?>?Fe?>?Mn?>?Se?>?Cu?>?Ni?>?Cd in gills, Fe?>?Zn?>?Se?>?Mn?>?Cu?>?Ni?>?Cd in liver and gonad, and Zn?>?Fe?>?Cu?>?Mn?>?Se?>?Ni?>?Cd in kidney. It was concluded that the fish from the dam lake are not heavily burdened with metals, but they should be controlled periodically to avoid excessive intake of trace metals by humans, and to monitoring the pollution of aquatic environment.  相似文献   

5.
The concentrations of Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Sn and Zn were analysed in water, sediment, muscle of climbing perch fish (Anabas testudineus), and tissue of water hyacinth plants (Eichhornia crassipes) collected from a former tin-mining pond in Perak, Malaysia. The monitoring was performed during the minimum and maximum rainfall periods. The concentrations of As, Cr, Fe, Ni, Pb and Zn in water exceeded the permissible limits set by the Interim National Water Quality Standards for Malaysia (INWQS). The risk index (RI) values determined for As, Cd, Cr, Cu, Hg, Pb and Zn in sediment presented a low degree of ecological risk. The order of the top three heavy metals measured in fish muscle was Zn?>?Fe?>?Al. The estimated daily intake (EDI) of As and Cr exceeded the allowable limits in both rainfall periods. The bioconcentration factor (BCF) and translocation factor (TF) values of Zn in water hyacinth were 24.865 and 3.214, respectively. The concentrations of Cu and Zn in the plant tissue were significantly correlated (p?<?.05) with the concentrations of heavy metals in water. Overall, climbing perch and water hyacinth are excellent bioindicators of environmental impacts on water bodies.  相似文献   

6.
A study was conducted between March 2006 and February 2007 to assess the concentration of Fe, Zn, Cu, Mn, Pb, and Cr in the gills and muscles of six fish species (Chrysichthys nigrodigitatus, Clarias anguillaris, Tillapia zillii, Mormyrus rume rume, Mormyrus macrophthalmus and Mormyrus tapirus) from lotic freshwater ecosystem at Afikpo South- East Nigeria using Atomic Absorption Spectrophotometer. In all the fish species studied the concentration of metals in the gills was significantly higher than that of the muscles (p<0.05). While the highest concentration (mg l(-1)) of Fe (702.20 +/- 0.04), Zn (34.40 +/- 0.02), Cu (2.10 +/- 0.01), Mn (4.91 +/- 0.08) Pb (0.50 +/- 0.02) and Cr (1.12 +/- 0.07) were recorded in the gills of C. nigrodigitatus, that in the muscles were recorded in T. zillii (443.20 +/- 0.08, 23.30 +/- 0.06, 1.33 +/- 0.06, 3.09 +/- 0.02, 0.31 +/- 0.01 and 0.66 +/- 0.04 for Fe, Zn, Cu, Mn, Pb and Cr respectively). The lowest concentration of all the heavy metals in the gills was recorded in M. tapirus (309.00 +/- 0.07, 16.45 +/- 0.03, 0.92 +/- 0.04, 2.15 +/- 0.04, 0.21 +/- 0.01 and 0.50 +/- 0.06 mg l(-1)for Fe, Zn, Cu Mn, Pb and Cr respectively) while the lowest in the muscles was recorded in C. anguillaris [Fe (186.00 +/- 0.07), Zn (14.20 +/- 0.08), Cu (0.56 +/- 0.03), Mn (1.30 +/- 0.02), Pb (0.10 +/- 0.01) and Cr (0.28 +/- 0.04)]. The order of heavy metals concentrations in both the gills and muscles was Fe>Zn>Mn>Cu>Cr>Pb. While the concentration of Zn, Cu and Pb both in the muscles and gills of all the six fish species studied were within the WHO and FEPA prescribed limits, that of Fe(except in the muscles), Mn and Cr were above the prescribed limits thus indicating contamination of the fish species by these metals. Fe has the highest bio-concentration factor (BCF) in both tissues while the least was Cu. Periodic monitoring of these metals in both fishes and river to ensure safety is advocated.  相似文献   

7.
将无锡城乡交错区河网分为城镇生活区水巷、工业区主河道、农业区主河道、农业区支流和鱼塘5种类型区.通过秋季(旱季)和夏季(雨季)2次采样,研究氮、磷和Cu、Zn、Pb、Cr、Cd在地表水和沉积物中的含量及其空间变化.结果表明:(1)城乡交错区地表水氮、磷来源于生活污染和工业污染的比例大于农田,同时具有来源分散、污染面广的特征.(2)由于城镇地表径流和工业活动影响,各类型区地表水重金属含量均有不同程度提高.但地表水重金属主要沿主河道迁移,旱季和雨季主河道重金属含量均大于农业区支流,而且随着与城镇距离增加,主河道沉积物重金属含量迅速降低,重金属污染影响范围较小.(3)与重金属相比,地表水氮、磷污染仍是太湖水网区主要的环境问题.但城镇及其周围河流沉积物中富集的重金属含量很高,其潜在环境风险不容忽视.  相似文献   

8.
Concentrations of ten metals (As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn and Hg) in the edible muscle of Arius maculatus captured from eight different near‐shore and off‐shore sites off the south west coast of the Arabian Sea, Pakistan, were determined by atomic absorption spectrophotometry. Relevant water and sediment samples from the sites were also analysed for the metals. Zinc showed the highest metal concentration (6.763 μg/g, wet weight) in the muscle of the fish, while Mn and Hg showed lowest level (0.019 μg/g, wet weight). Of all the metals investigated, largest scatter (measured as σ) was observed for Zn = 2.058 /μg/g) in fish muscle, for Fe and Mn in sediment (σ = 27481 and 44.50 μg/g) and for As in water (σ = 0.270 μg/L). The metal distribution data pertaining to water, fish and sediment were examined on the basis of simple metal correlations. The statistical study revealed that Ni, Cr, Pb and Cu had significant positive correlations (r > 0.830 at ρ = 0.01). The finding substantiated a trace metal concentration gradient in the area, thereby indicating that the local marine environment is contaminated by anthropogenic sources.  相似文献   

9.
The concentration of heavy metals was analyzed each of 20 river water, suspended sediments and bed sediments along the stretch of Swarnamukhi River Basin. River water is not contaminated with heavy metals except Fe and Mn. Contamination factor in sediments shows considerable to very high degree contamination with Cr, Cu, Pb and Zn. The sources of these metals could be residential wastes, sewer outfall, fertilizers, pesticides (M-45 + carbondine) and traffic activities apart from natural weathering of granitic rocks present in the basin area. Principal component analyses indicate the interaction between metals in different media. The comparison of metals (Cu, Pb and Zn) in bed sediments of Swarnamukhi River with the Indian and world averages indicates that the values obtained in the basin are above the Indian averages and far below to the world averages. Average shale values and sediment quality guidelines point toward the enrichment and contamination of Cu, Cr, Pb and Zn to several fold leading to eco-toxicological risks in basin.  相似文献   

10.
通过对温瑞塘河温州市区典型河段44个表层沉积物样品重金属含量进行监测和分析,应用地积累指数法和生态因子富集法等对典型重金属元素Cu、Zn、Pb、Cr、Fe、Mn、Ni进行污染评价和空间特征对比,结果表明:各重金属污染程度从高到低依次为:Zn〉Cu〉Pb〉Ni〉Mn〉Fe〉Cr,其中Zn、Cu在多数样点呈现重污染状态,含量分别为126.19~4312.07mg/kg及18.64~635.54mg/kg,Pb呈中度污染状态,含量为51.30~252.76mg/kg,而Ni、Mn、Fe、Cr基本处于无污染或轻微污染状态。绝大多数采样点出现3种以上重金属元素的复合污染,两种评价方法得出的结论基本一致,山下河重金属污染明显比九山外河更为严重,城市功能结构调整成为城市河网水环境治理的基础。  相似文献   

11.
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   

12.
In Korea, the heavy metal pollution from about 1,000 abandoned mines has been a serious environmental issue. Especially, the surface waters, groundwaters, and soils around mines have been contaminated by heavy metals originating from acid mine drainage (AMD) and mine tailings. So far, AMD was considered as a waste stream to be treated to prevent environmental pollutions; however, the stream contains mainly Fe and Al and valuable metals such as Ni, Zn, and Cu. In this study, Visual MINTEQ simulation was carried out to investigate the speciation of heavy metals as functions of pH and neutralizing agents. Based on the simulation, selective pH values were determined to form hydroxide or carbonate precipitates of Cu, Zn, and Ni. Experiments based on the simulation results show that the recovery yield of Zn and Cu were 91 and 94 %, respectively, in a binary mixture of Cu and Zn, while 95 % of Cu and 94 % of Ni were recovered in a binary mixture of Cu and Ni. However, the recovery yield and purity of Zn and Ni were very low because of similar characteristics of Zn and Ni. Therefore, the mixture of Cu and Zn or Cu and Ni could be recovered by selective precipitation via pH adjustment; however, it is impossible to recover selectively Zn and Ni in the mixture of them.  相似文献   

13.
选取太湖、巢湖污染较为严重的区域为研究对象,采集季节性沉积物柱状样,以0.5cm的间距高精度分割样品,分析其中的Fe,Mn,Cu,Zn等重金属元素的含量,对沉积物中重金属的总量特征及季节性变化特征进行了分析,得出以下结论:太湖、巢湖沉积物中重金属的总量均呈现出Fe>Mn>Zn>Cu的特征,季节性变化幅度为Mn>Fe>Zn>Cu,重金属元素的地球化学性质对其季节性变化有很大的影响.同时,不同的区域背景差异(如元素丰度、污染状况等)导致了太湖、巢湖采样点沉积物中重金属元素季节性特征的差异.  相似文献   

14.
对衡阳市菜园使用的12个有机肥样品中的Zn、Cu、Cr、Pb、Cd、Ni、Hg和As的指标进行检测,样品中重金属总As、总Hg、总Pb、总Cd、总Cr等的含量按照中国NY525—2012有机肥料重金属限量指标,总Ni、总Cu、总Zn重金属参照德国腐熟堆肥中重金属限量标准进行分析,结果表明,除牛粪、菜籽饼肥外,有9个样品均发现有超限量值的重金属成分,超标样品数占总样品数的75%,超标的重金属成分以Cu和Zn较为普遍,分别占样品总数的75%和41.7%.而在超标程度方面,有两个样品的中的Cu和两个样品中的Cr均为严重超标.这些肥料使用不当,对菜园土和蔬菜品质产生不良影响,应给予关注.  相似文献   

15.
Green-lipped mussels, Perna viridis, were collected from the eastern and western parts of the Johore Straits in September 2004 and January 2005. Based on the heavy metal concentrations in the different soft tissues (gonad, foot, mantle, gills, muscle, and remaining soft tissues) of these mussel samples, the eastern part of the Johore Straits (which is divided into two portions by a causeway), recorded higher levels of bioavailability and contamination by Cd, Cu, Fe, Ni, and Zn when compared to the western part, while Kg. Pasir Puteh in the eastern part was found to record the highest bioavailability and contamination by heavy metals. The use of different soft tissues of P. viridis as biomonitors of bioavailability and contamination by Cd, Cu, Fe, Pb, Ni, and Zn in the semi-enclosed Johore Straits is proposed, since erroneous results due to spawning and the problem of defecation before dissection could be overcome. Hence, a more accurate interpretation of the bioavailability and contamination by heavy metals in coastal waters could be obtained. To our knowledge, this is the most detailed study on the bioavailability and contamination of heavy metals in the Johore Straits on the Malaysian side of the waterway carried out by using the different soft tissues and metal distribution based on the Mussel Watch approach.  相似文献   

16.
The present study was conducted to determine the heavy metal contamination in soil with accumulation in plants in waste water irrigated areas. Results revealed that waste water contained lower concentrations of Cr, Zn, Cu, and Pb except Cd (0.03) than the permissible limits prescribed by the World Health Organization. The maximum metal concentrations occurred in Brassica oleracea (Zn 63.80, Cu 12.25, Cr 10.65, Pb 3.63, and Cd 0.56 mg Kg?1).The metal enrichment (EF of Cd 1.9, Cr2.9, Zn 4.8, Cu 6.5, and Pb 15.5) and degree of contamination (CF of Cd 2.9, Cr 2.0, Zn 2.3, Cu 2.7, and Pb 2.2) showed that accumulation of the five toxic metals increased during sewage irrigation as compared with the reference values, other Indian regions and globally. However, based on WHO standards for heavy metal contamination of soil and irrigation water, our data does not ensure safe levels for food.  相似文献   

17.
Abstract

Analyses were made of heavy metals, manganese, nickel, copper, zinc and lead in water samples and soft body, shell and different tissues (gills, digestive glands, mantle and viscera) of the Unionid mussel, Lamellidens marginalis collected from two tributaries of the Cauvery river. Water samples from Station I contained higher concentrations of the metals than those from Station II. the concentration of metals in water at both stations were in the descending order: Mn > Zn > Pb > Ni > Cu. However, the concentrations of metals in the soft body were in the descending order: Zn > Mn > Pb > Ni > Cu at both stations in all size groups of mussels tested. the concentration of zinc maintained a linear relationship with the size of the mussels, but manganese showed a reverse trend. Small size (4-5 cm) mussels accumulated more manganese (105.5 μg.g?1 dry wt.) than larger ones (7-8 cm; 6.5 μg.g?1 dry wt.). Both young and old is accumulate the same level of lead, copper and nickel in the soft body. the order of concentrations of metals (Mn, Pb, Zn, Ni and Cu) in the shell of mussels from both stations coincided with the order of concentrations of background water except for lead. the accumulation of lead was higher in shell (30.4-36.2 μg.g?1 dry wt.) than in soft body (6.4-12.0 μg.g?1 dry wt.). the pattern of concentration of metals in the various tissues reveal that the digestive glands have greater ability than other tissues to concentrate most metals under study. the concentration factors for soft body, shell and different tissues are presented. the advantages in using the common mussel for biomonitoring of contaminants in water is also discussed.  相似文献   

18.
Although Lebanon has abundant water, its rivers are polluted and aquifer water mismanaged. Effective river water usage requires an understanding of the geochemistry of polluting metals in catchments. Climate is “Mediterranean”: wet winters and dry summers. Active sediment flushing is restricted to winter high discharge episodes. Except in winter, water column pollutants are removed by precipitation or sorption to the surface of static bed sediments. Hence (1) does winter flushing of contaminated sediment and replacement by clean sediment favour self purification? (2) does the distribution of metals between extractable fractions change seasonally and thereby affect metal bioavailability ? Results on the distribution of metals are reported for Fe, Pb, Zn, Cu and Cd in bed sediments from Nahr Ibrahim (a karstic river) for summer and winter. A Tessier-like sequential extraction scheme was applied to samples (< 75 μm) for five locations along a 13 km stretch to the sea. Water pH was above 8.2 at all locations implying a very low solubility for Fe. Sediment was derived from catchment soils and limestone. Total sediment Fe increased in winter at all sites following deposition of eroded soil from upstream. Cadmium, Cu and Pb derived from polluting sources; the sources of Zn were more complex. Dilution by clean sediment explained winter reductions in total Cd, Cu and Pb; Zn changes were less consistent. Iron occurred mostly (> 77 sum of fractions) in the residual fraction compared with 6– 31 for pollutants; residual Cu and Zn showed a small increase in winter whereas Cd and Pb did not change. All readily exchangeable metals decreased in winter and the carbonate bound forms predominated in both seasons. Nahr Ibrahim has a high capacity for self purification and metal resolubilisation from sediment will be limited by the solubility of carbonate forms.  相似文献   

19.
Five trace metals (Cu, Zn, Fe, Mn and Cd) were determined in different tissues and organs (muscle, liver, brain, gills, gonads and intestines) of some Tilapia spp. (Oreochromis spp. and Sarotherodon galilaues) collected from two Egyptian Lakes (Edku and Mariut, exposed to different types of pollutants), El-Umum Drain, and from the fishing farm El-Nozha Hydrodrome. Our results indicate that metal accumulation in different organs vary considerably between the same and among different Tilapia spp. There is a preferential accumulation of metals by different organs. Liver is a target organ for Cu accumulation, whereas the brain and flesh tissues clearly accumulate more levels of Zn than the other studied elements. Amongst the studied elements, Cd concentrations in the different organs are the lowest. It was found that edible parts of Tilapia spp. collected from Lake Mariut accumulate the highest levels of the studied elements (Fe, Zn, Mn and Cu for S. galilaues and Cd for Oreochromis niloticus), compared with those in the other studied areas. In general, the levels of Cd (0.0-0.11 ppm), Cu (0.25-1.85 ppm) and Zn (3.58-8.46 ppm) in the edible parts of studied fish cannot be considered as hazardous levels.  相似文献   

20.
污染源解析是城市大气环境精准防治的重要基础。为探究典型工业城市大气降尘中重金属污染分布特征和污染源解析,本研究在济南市域内采集了35个大气降尘样品,分析了样品中重金属浓度及其空间分布特征,采用正定矩阵因子分析模型(Positive Matrix Factorization,PMF)解析降尘中重金属来源。研究结果表明,降尘中Mn、Fe、Co、Ni、Cu、Zn、As和Pb浓度平均值分别为501.4、29884.6、8.2、24.8、44.3、153.9、12.5、40.1 mg·kg-1,其中Zn、Cu和Pb的地累积指数(Geoaccumulation Index,Igeo)分别为1.17、1.06和1.01,属于中度污染;钢铁冶炼较为发达的钢城区降尘中Mn、Fe、Co、Cu和As浓度显著高于其他区县,其浓度平均值分别为1172.4、73577.3、17.0、139.7、32.3 mg·kg-1,而Zn和Pb在历下区、槐荫区等人口密集区域最高浓度可达351.5 mg·kg-1和114.0 mg·kg-1;PMF分析结果表明,济南市降尘重金属主要存在4个贡献源,分别为土壤源、工业源、交通源和混合源,贡献率分别为46.8%、26.6%、15.2%和11.4%。其中,重金属Co、Cu、Fe主要来自土壤源,Mn主要来自于土壤源和工业源的贡献,Ni主要来自于土壤源和混合源,交通源对降尘中Pb和Zn的贡献率较高,As则主要来自于工业源。本研究结果可为济南市大气环境精准防控政策的制定提供理论依据。  相似文献   

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