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1.
Heavy Metal Transport in the Hindon River Basin, India   总被引:1,自引:0,他引:1  
Total mass transfers of heavy metal in dissolved and particulate form has been determined in the downstream section of river Hindon, an important tributary of river Yamuna (India). The contribution of different point sources to the river Hindon has also been assessed. The river Kali has the largest contribution to the river Hindon. The highest metal loads were related to the highest flow of the river and thereby increased both by surface runoff and sediment resuspension. The contribution of monsoon months to the total transported load was also calculated and it was observed that monsoon months contributes more than 40% of total loading annually for all the metals. The metal fluxes from the river Hindon were compared with other rivers of Indian sub-continent.  相似文献   

2.
海河干流(市区段)表层沉积物重金属污染及变化趋势分析   总被引:7,自引:0,他引:7  
根据1990—2006年监测资料,对海河干流(市区段)沉积物中重金属的现状和变化趋势进行了分析,采用地积累指数和Hakanson危害指数对海河干流(市区段)沉积物重金属富集现状和对水生生物危害进行评估。结果显示:海河干流(市区段)表层沉积物除Zn外,均呈现污染下降趋势。海河干流(市区段)沉积物中重金属对生物潜在危害顺序为Cd〉Hg〉As〉Cu〉Pb〉Cr〉Zn,各项指标对生物潜在危害性上游大于下游。  相似文献   

3.
An in-depth study on various locations along the Kuwait Coastdifferentiated by the nature of coastal topography, humanhabitation and industrialization was made during the year1995–1997 in relation to the gills of the gastropod, Cerithium scabridum, a bio-indicator of heavy metal pollution.The maximum concentration of heavy metals in the gills of C. scabridum, seawater and particulate matter was observed inStations III when compared to the metal concentrations in theother seven stations. Co-efficient Variance (CV) revealed anincrease in the accumulation of Cu and Pb in gills, seawater andparticulate matter in winter than in summer. However, the CV wasnoted to be lower in winter than in summer in the case of Cr andV, in gills of C. scabridum and Ni in the case of seawatersamples. Further, by ANOVA, except V, significant relationshipswere noted between the heavy metals (Cu, Cr, Pb and Ni) andvarious locations in the gills of C. scabridum.  相似文献   

4.
The Fractionation of Fe, Zn, Cu, Pb, Mn and Cd in the sediments of the Achankovil River, Western Ghats, India using a sequential extraction method was carried out to understand the metal availability in the basin for biotic and abiotic activities. Spatial distribution of heavy metals has been studied. Sediment grain size has significant control over the heavy metal distribution. The fluctuations in their concentration partly depend upon the lithology of the river basin and partly the anthropogenic activities. The sediments are dominated by sand and are moderately to strongly positively skewed and are very leptokurtotic in nature. The quartzite and feldspars are abundant minerals along with significant amount of mica with low clay content. The core sediments show increasing trend of heavy metal concentration with depth due to the recent addition of anthropogenic sources and post-diagenic activities. Significant amount of Cd (18%) was found in carbonate fraction, which may pose environmental problems due to its toxic nature. Small concentrations of metals, except Cd and Cu, are in exchangeable fraction, which indicate low bio-availability. Enrichment Factor (EF) for individual metals shows the contribution from terrregious and in part from anthropogenic sources. Selective Sequential Extraction (SSE) study shows the variation in specific metal distribution pattern, their distribution in different phases and their bio-availability. Maximum amount of the metals were bound to the non-residual fractions (mainly Fe-oxides). Overall, bio-availability of these micronutrients from sediments seems to be very less. Non-residual phase is the most important phase for majority of heavy metals studied. Among the non-residual fraction, maximum amount of the heavy metals bound to Fe-oxides. The study high lights the need for in-depth study of heavy metals distribution and fractionation in the smaller river basins to get precise information on the behavior and transport of heavy metals in the fluvial environment and their contribution to the world ocean.  相似文献   

5.
Sequential chemical extraction was used to study the operationally determined chemical forms of five heavy metals (Pb, Cu, Zn, Co and Ni) and their spatial distribution in the sediments. The binding behaviour of heavy metals associating with Fe–Mn oxides showed a good correlation towards Cu, Zn and Co, but moderate linear dependence with Ni and Pb. Among the five metals, correlation between Fe–Mn oxide bound Cu and Fe–Mn oxides (r = 0.95) is highest. The coefficient of determination (r 2) in organically bound heavy metals versus organic matter (OM) ranges from 0.772 to 0.952, which indicates a good linear dependence. The OM fraction in the sediments is more accessible to heavy metals and is the major ligand available for complexation. In particular, Zn and Cu are preferentially bound to OM. In general, Zn co-precipitation with carbonates is the dominant chemical form when Fe–Mn oxide and OM are less abundant. In this study, however, carbonates were less abundant, hence Zn bound to carbonates was less pronounced. Based on the results, even if the excessive binding sites are contained in the sediments, competition of various complexation reactions between sediment phases and heavy metals could dominate metal association.  相似文献   

6.
以无锡市望虞河西岸河网区为研究区域,于2018年12月—2019年9月分冬、春、夏、秋4个季节采集了上覆水和沉积物样本,研究氮磷营养因子在沉积物-上覆水界面的释放规律,探究主要水质指标、沉积物氮磷和重金属含量的时空分布特征。结果表明:研究区域内的水质状况不佳,主要是氮含量超标,污染严重的点位集中在人类活动较为密集的市区和工业区;受上覆水氮磷浓度、溶解氧浓度等变化的影响,沉积物营养盐含量季节变化明显,污染状况较为严重,75%的点位属于中度和重度污染;沉积物重金属含量季节变化不显著,部分重金属的空间分布特征相似,污染程度排序为Zn>Cd>Cu>Pb>Ni>Cr>As。  相似文献   

7.
南方某河流型饮用水源地重金属健康风险评估   总被引:1,自引:0,他引:1  
对南方某河流型饮用水源地水中重金属含量进行调查研究,并应用美国环保局推荐的健康风险评价模型对其进行健康风险评价。结果表明,该饮用水源地水中重金属类污染物健康风险值相对较低,其中重金属类致癌污染物的健康风险均值大小顺序为CrAsCd,其值分别为8.19×10-6、2.11×10-6、1.59×10-7a-1,Cr、As的风险值高于瑞典、荷兰、英国推荐的最大可接受水平(1×10-6a-1),而低于国际(ICRP)与美国环保局的健康风险可接受水平(5×10-5a-1和1×10-4a-1),成为该饮用水源地的主要致癌污染因子。重金属类非致癌污染物的健康风险均值大小顺序为CuNiZn,其值分别为1.95×10-10、1.19×10-10、5.73×10-12a-1,均远远低于致癌污染物的健康风险值。  相似文献   

8.
为了解渭河陕西段表层沉积物重金属的污染特征,采用ICP-MS分析了13个采样断面表层沉积物中As、Cd、Cr、Cu、Mn、Ni、Pb和Zn 8种重金属的含量,并对其来源和生态风险进行了评价。结果表明:渭河陕西段8种重金属的平均含量顺序依次为Mn > Zn > Cr > Cu > Ni > Pb > As > Cd;除Ni外的其余7种重金属的平均含量均超过陕西省A层土壤背景值。各断面表层沉积物重金属的潜在生态风险指数(RI)介于111.4~7 043.7,其中23.1%的断面有极强生态风险,46.2%的断面为中等生态风险,其余为轻微生态风险。Cd污染最为严重,对各断面的潜在生态风险介于较强生态风险与极强生态风险之间,对RI的贡献平均为85.2%;其余7种重金属在所有断面均属于轻微生态危害。渭河陕西段表层沉积物As、Cd、Cu和Zn主要为工业与农业来源;Cr和Ni主要为自然来源;Pb和Mn与城市污水和交通污染来源有关。  相似文献   

9.
This study aimed at assessing atmospheric deposition of heavy metals and other elements using the moss genera Brachythecium sp. (B. rutabulum and B. salebrosum) and Eurhynchium sp. (E. hians and E. striatum) collected in autumn 2004 in the urban area of Belgrade. The concentrations of 36 elements (Na, Mg, Al, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Br, Rb, Sr, Mo, Sb, I, Cs, Ba, La, Ce, Sm, Tb, Dy, Hf, Ta, W, Hg, Th, U) were determined in moss and local topsoil samples by instrumental neutron activation analysis. The concentration of elements in moss positively correlated to those obtained for topsoil. High enrichment factors for As, Zn, Mo, Br, Sb, Se, Hg and Cl, calculated to continental crust composition, gave an evidence for anthropogenic impact on urban area, mainly due to intensive vehicular traffic and fossil fuel combustion. The concentration of elements in moss, characteristic for fossil fuel combustion, obtained in this study were substantially lower than in the previous investigation (2000) conducted in the area of Belgrade. The level of concentrations for V, Cr, Ni, and As in moss from this study correlated to those measured for neighboring countries, and were several times higher than the base-level data from low polluted areas. The level of accumulated elements in both investigated moss genera were similar and all studied species could be combined for biomonitoring purposes in urban areas.  相似文献   

10.
High concentrations of arsenic in ground waters in West Bengal and Bangladeshhave become a major cause for concern in recent years. Given the enormity and the severity of the problemof arsenic poisoning, a task of evaluating the commercially available arsenic detection field kits for their capabilities was undertaken. In the light of the findings, generic specificationswere recommended which could form the basis forindigenous manufacture of these kits in the arsenic affected countries. This article presents the results of the laboratory and fieldevaluation conducted in Bangladesh and West Bengalof five arsenic testing field kits. The salient features of the kits, their merits and limitationshave been brought out. Based on the criteria of kitdesign, quality of chemicals used, colourcomparator charts, detection range, time required for analysis, cost etc., a comparative ranking ofthe kits has been made to facilitate the choice of the kit to meet specific requirements.  相似文献   

11.
南宁市河流型水源地重金属污染调查与健康风险评价   总被引:2,自引:0,他引:2  
通过对南宁市河流型水源地水体中Pb、Cd、Hg、As浓度调查与健康风险评价研究,结果表明:这4种元素在水体中的质量浓度较低,均达到《地表水环境质量标准》(GB 3838-2002)Ⅱ类标准;经饮水途径引起的健康风险从大到小依次为AsCdPbHg,说明As是南宁市饮用水源中的主要风险因子;4种元素通过饮水途径引起的平均个人年健康致癌风险值为1.48×10-6a-1~13.75×10-6a-1,非致癌风险值为7.05×10-10a-1,均低于美国环保局和国际辐射防护委员会的推荐值。  相似文献   

12.
在往复流现象明显的蕰藻浜中下游河道选择16个采样点,分析研究沉积物性状以及Cr、Cu、Zn、Cd、Ni、Pb、Mn的含量以及分布情况。结果表明:蕰藻浜总体污染程度为中等,其中陈行桥、江杨北路桥以及淞港码头污染较严重。Cr、Cd、Pb、Ni、Cu、Zn和Mn的含量分别为24.0~357.0、0.06~0.69、20.0~85.4、18.2~132、14.2~136、84.6~685、472~1 086 mg/kg。通过分析发现,Pb、Ni、Cu、Zn和Cr总量都具有显著的相关性,很有可能来自同一外源污染,而中游河段的Mn主要来自于沉积物母质。河道两岸以往的工业与生活排污以及往复水流使得重金属污染物在沉积物中聚集是造成重金属污染的潜在原因。运用地累积指数法、潜在生态危害指数法、污染负荷指数3种风险评价法对沉积物重金属进行风险评估,总体来说,3种评价方法都表明Cu的污染程度较严重,Mn的污染较轻。其中地累积指数法结果显示,各重金属的污染顺序为CuZn≥CdPb≥CrNiMn,然而由于Cd本身生物毒性较高,对沉积物生态环境危害贡献率可达到60%;污染负荷指数评价结果发现蕰藻浜下游河段部分断面沉积物达到了极强污染程度,应当受到重视。  相似文献   

13.
This study examined the levels of seven heavy metals (namelyzinc, copper, cadmium, chromium, lead, manganese and iron) andtheir associations with magnetic properties in playground dustof Hong Kong. Results showed that the playground dust containedhigh concentrations of Zn (mean = 1883 g g-1), Cu(mean = 143 g g-1) and Cr (mean = 263 g g-1).Qualitative examination of dust samples under microscope indicated local traffic as one of the important pollutant sources. Magnetic measurements indicated that these anthropogenicpollutants mainly consisted of coarse-grained multidomain (MD) ferrimagnetic minerals. Superparamagnetic (SP), stable single domain (SSD) ferrimagnetic grains and non-ferrimagnetic mineralswere present in relatively small amounts. Significant correlations between heavy metals and various magnetic parametersindicated a strong affinity of heavy metals to magnetic minerals hence pointed out the potential of magnetic properties for simpleand rapid proxy indications of heavy metal pollution in playground dust.  相似文献   

14.
研究中国西南某省不同类型尾矿的重金属浸出量及总量,为尾矿的污染防范、环境管理和综合利用提供参考和建议。采集了14种类型共164个有代表性尾矿进行浸出毒性试验,并分析其中79个典型尾矿样品的9种重金属含量,以评估其污染风险和综合利用价值。结果表明,有5种类型共7个样品出现浸出毒性超标,分别为铅锌矿、镍矿、银矿、铁矿、锰矿,总体超标率为4.3%。超标元素分别为砷、镉、锌、铅、铜、镍等6种元素,最大超标倍数分别为砷18.3倍、锌4.8倍、镉3.0倍、铅0.56倍、铜0.32倍、镍0.16倍;尾矿含有较多重金属,其中砷、锌、铅、铜含量较高,最高分别达到11.75%、2.60%、1.01%、0.29%,不同类型尾矿其重金属含量各有不同,铅锌矿尾矿的重金属总量最高。总体上,该省绝大多数尾矿为普通固废,少部分为危险废物,砷、镉、锌、铅、铜、镍等6种元素存在污染风险,其中砷元素是最主要污染物;尾矿由于重金属含量较高而有一定的综合利用价值。  相似文献   

15.
以松花江流域的野生鱼类为研究对象,在松花江流域选取松林、大顶子山、佳木斯3个具有代表性的点位,在2014—2016年的每年5月底6月初采集鲤鱼和鲫鱼样品,3年内共制备45个鲤鱼单样,44个鲤鱼混样,30个鲫鱼混样,共计119个。采用电感耦合等离子体-质谱法对鱼类肌肉组织中残留的As、Cd、Cr、Pb、Hg 5种重金属进行检测。检测结果显示,As、Cd、Cr、Pb、Hg 5种重金属全部检出,检测结果全部达标,达标率为100%。根据检测结果采用单因子指数法和金属污染指数法等评价了松花江流域鱼体重金属残留状况及食用安全性,评价结果为松花江流域鱼类重金属残留量相对较少,鱼体健康,食用安全。  相似文献   

16.
Heavy Metal Pollution Assessment in Sediments of the Izmit Bay, Turkey   总被引:6,自引:0,他引:6  
Surface sediments in the fraction < 63 μm collected from eight stations along the north coastline of Izmit Bay, north-eastern Marmara Sea, Turkey, were analyzed for major (organic carbon, Al, Ba, Fe and Mg) and trace (As, Cd, Co, Cr, Cu, Mo, Ni, Pb and Zn) elements by using inductively coupled plasma atomic emission spectrometry (ICP-AES). Sediments heavily contaminated are evaluated by the Sediment Quality Guidelines (SQG) of US EPA. The results were compared with the marine sediment quality standards (SQS), as well as literature values reported to assess the pollution status of the sediments. The enrichment factors (EFs) were calculated to evaluate actual level of contamination for all the elements using the earth crust as reference matrix, based on elemental values by Mason which show a normal pattern near to unity. The analysis revealed two groups of elements: (i) Arsenic, Cd, Pb, and Zn are the most enriched elements; (ii) Barium, Co, Cr, Cu, Fe, Mg, Mo and Ni are at background levels. The results show that road traffic run-offs, paint industries and coal combustion are among the most significant sources.  相似文献   

17.
In this study concentrations of heavy metals, such as Cd, Co, Cu, Fe, Mn, Ni, Pb and Zn were determined in water, sediment, muscle, liver and gill of fish (Silurus triostegus, Mastacembelus simack, Mystus halepensis, Orthrias euphraticus) the muscle and liver of crab (Potamon fluviatilis), the internal organs of fresh water snail (Physa acuta), and mussel (Unio elongatulus), and in whole biomass of green algae (Spirogyra sp.) examples collected seasonally from three selected sites (I, II, and III) of Tigris River and from a reference site on Resan Creek. In general, the average Cd, Cu, Mn, Ni, Zn, and Fe values in Sites I, II, and III were found to be high in spring and summer. The concentrations of heavy metals in the Tigris River are compared with previous studies in the same sites. The results showed that Cu levels have gradually decreased during recent years. In Tigris River, among the living organisms, i.e., those which are living in benthic region and showing biomonitor characteristic, crab, snail, green algae, mussel and fish are seen to be formed in sequence. Cu, Fe, Mn and Zn values obtained from the muscle of fish and from the mass of internal organs of mussel and snail were found to be under the acceptable values suggested.  相似文献   

18.
Live feeds, especially Tubifex spp., which are collected from a wide variety of polluted habitats, are used by aquarium fish keepers in India. These habitats receive domestic sewage and industrial wastes from nearby residential and industrial areas. Reports of morbidity and mortality from aquarium fish culturists in and around Mumbai led to the present investigations on the ecology of these habitats with a view to assess the water quality, presence of heavy metals in the environment and their bioaccumulation in Tubifex worms, and to examine whether these habitats could be exploited to meet the demand of the industry. Six natural red worm (Tubifex spp.) collection centres in Mumbai and Thane districts of Maharashtra state in India constituting a major source of live Tubifex supply to aquarium fish industry were evaluated for pollution, heavy metal concentration in water, sediments and in the body tissues of Tubifex. Data revealed the presence of heavy metals in water and sediments at collection sites and bioaccumulation of cadmium, iron, lead, zinc and copper in body tissues of Tubifex worms. Cadmium ranged from 2.38 to 7.21 mg/kg, iron 671.9 to 5738 mg/kg, lead 14.95 to 33.49 mg/kg, zinc 60.20 to 166.60 mg/kg and copper 29.38 to 108.90 mg/kg of dry Tubifex worms. The study suggests that all the six collection sites are polluted and the red worms contaminated with heavy metals and hence, unfit for use in aquaria or feeding any variety of fish or crustaceans in the hatcheries.  相似文献   

19.
采用石墨炉原子吸收分光光度法、双道原子荧光光谱法研究乌鲁木齐市采暖期前期与后期不同粒径大气颗粒物(TSP、PM_(10)、PM_5、PM_(2.5))中Hg、As、Zn、Pb、Ni等5种重金属元素的质量浓度,并对重金属污染水平进行评价。Hg质量浓度为0.3~5.7 ng/m3;As质量浓度为15.3~122.5 ng/m~3;Zn质量浓度为298.0~1 686.5 ng/m~3;Pb质量浓度为0.5~88.8 ng/m~3;Ni质量浓度为10.4~25.5 ng/m~3。Igeo计算得出采暖期后期的TSP、PM_(10)、PM_5、PM_(2.5)中各重金属Igeo值均高于采暖期前期,其中Hg元素为严重污染;富集因子分析得出Hg、Zn元素的EFi值大于10,说明这些元素是人为源贡献。通过研究乌鲁木齐市不同时期、不同粒径大气颗粒物中各种重金属污染状况,为乌鲁木齐大气污染治理提供科学支持。  相似文献   

20.
湖南省某冶炼厂周边农田土壤重金属污染及生态风险评价   总被引:6,自引:3,他引:3  
利用野外采样与实验室分析相结合的方法,以湖南省某冶炼厂周边农田土壤(0~20 cm)为研究对象,监测了Cd、As、Pb、Cr、Cu、Zn、Hg等7种重金属的含量,并对重金属污染程度与潜在生态风险进行了评价。结果表明,7种重金属都存在不同程度的超标或污染,其中Cd、As、Pb等的污染较为严重。统计学分析结果表明,Pb、As、Hg、Zn、Cd等来源相同,可能主要都来自于人为污染,即冶炼作业造成的污染。7种重金属化学形态不尽相同:在重金属有效态中,Cd的水溶态和可提取态较高;Pb、Cu、Zn可还原态、可氧化态这两部分含量较高。而Hg、As、Cr的残渣态含量较高。风险评价代码评价结果表明,Cd的生态风险较高,4.5%的样点Cd为极高生态风险,52.8%的样点Cd为高生态风险,42.7%的样点Cd为中度生态风险;100%的样点Zn为中度生态风险;Cu有60.1%的样点属于低生态风险,39.9%的样点属于中度生态风险;As、Pb主要以低生态风险为主(所占比例分别为77.2%、80%);Hg主要以无生态风险为主(所占94.3%)。Hakanson潜在生态风险指数法计算的综合潜在生态风险指数(RI)的范围为46.4~1 627.5,表明研究区域农田土壤存在很高的生态风险。上述各项结果综合表明,研究区农田土壤受到了严重的重金属污染,由此引起的重金属生态风险应引起高度关注。  相似文献   

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