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1.
Metal determination in human tissues is the most common application of biological monitoring for screening, diagnosis and assessment of metal exposures and their risks. Various biopsy-materials may be used. This paper deals with the quantitative determination of Cd, Pb, Cr, Mn, Fe, Ni, Cu, and Zn concentrations in nails of male subjects exposed to these metals alongwith their respective controls, while working in locomotive, carriage and roadways workshops, and lead battery factories. The levels of Cd, Pb, Cr, Mn, Fe, Ni, Cu and Zn in fingernails, assayed by atomic absorption spectrophotometry, were compared with their respective controls by student ‘t’ test. All the obtained values were correlated to the personal and medical history of the subjects under study. Significantly high levels of Cd, Pb, Cr, Fe, Ni, Cu and Zn were present in smokers, compared to nonsmokers. The concentrations of Cd, Pb, Cr, Mn and Fe were not significantly high in vegetarian subjects. It was also observed that there is no contribution of liquor towards nail-metal concentration. Significant correlations were observed between skin disease and Cr, Mn, Fe, Cu; hypertension and Cd, Mn, Cu; mental stress and Cd, Pb, Mn, Ni, Cu, Zn; diabetes and Cr, Mn, Ni; chest pain and Pb; respiratory trouble and Cr, Mn, Fe, Ni, Zn; tuberculosis and Zn; acidity and Cd; and ophthalmic problems and Mn, Fe, Ni, and Zn  相似文献   

2.
We analysed the concentrations of Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn in the water, sediments, fish and plants of the River Hindon, U.P., India, at seven sampling stations, in the year 1982. Considerable variation in concentration between water, sediments, fish and plants were noted. The concentration in the water was in the order Fe > Zn > Cr > Mn > Cu > Pb > Ni > Co > Cd, in the sediments, Fe > Mn > Zn > Ni > Cr > - Co > Cu > Pb > Cd; in a fish (Heteropnuestes fossilis) Fe > Zn > Mn > Pb > Ni > Co > Cu > Cd > Cr, and in a plant (Eicchornia crassipes) Fe > Mn > Zn > Ni > Cu > Cr > Pb > Co > Cd.  相似文献   

3.
Heavy metals in the site received industrial effluents were investigated to assess the pollution levels, distribution of metal among solid-phase fractions and possible metal sources. The soil samples at different depths of 0–5, 5–25 and 25–50 cm were collected and analyzed for Fe, Mn, Cd, Zn, Cu, Ni and Pb. Among all metals, Cd content was not detected in all soil samples. The average contents of Pb and Zn are higher than the corresponding values of common range in earth crust. Meanwhile, the maximum contents of Cu and Zn are higher than those of Dutch optimum value but lower that the Dutch protection act target value. The maximum contents of Cu, Pb and Zn are higher than the average shale value. The most investigated heavy metals are mostly found in the potentially labile pool (>50.0%) including metal bound to carbonate, Fe/Mn oxides, or organically fractions. Enrichment factor (EF) in combination with multivariate analysis including principal component analysis (PCA) and hierarchical cluster analysis (HCA) suggest that Mn and Ni associated with Fe in the soil samples were primarily originated from lithogenic sources. Pb was largely derived only from anthropogenic source, while Cu and Zn in the soil samples were controlled by the mixed natural and anthropogenic sources. These results suggest that discharging the industrial effluents into dumping site increased pollution level of Pb, Zn and Cu as well as enhanced their potentially labile pool that may be responsible for occurring potential toxic impacts on environmental quality.  相似文献   

4.
Recently hatched fry of brown trout were exposed to each of eight trace metals (Al, Cd, Cu, Fe, Mn, Ni, Pb, Zn) and to a mixture of all eight, at concentrations typical of soft acid waters, in flowing artificial soft water medium at pH 4·5 and 6·5, for 30 days. At pH 4·5, in the absence of trace metals, net uptake of Ca, Na and K and skeletal calcification were impaired but mortalities were low (10%). At pH 4·5, in the presence of Al, Cu, Pb and Zn individually and the mixture, mortalities were high (87–100%). Cd, Fe, Mn and Ni at pH 4·5 each caused some mortalities (17–43%) and impaired skeletal calcification. At pH 6·5, each of Al, Cd, Cu, Fe, Mn, Pb and the mixture of metals impaired net Ca uptake and (except Al, Fe and Pb) skeletal calcification. Net K uptake was impaired by Al and by the mixture, and less severely by Cu and by Fe. Net Na uptake was impaired by Al and by the mixture, and less severely by Fe and by Mn. The role of trace metals other than Al in fisheries'decline in soft acid waters is discussed.  相似文献   

5.
Ciceri  G.  Maran  Ciceri  Martinotti  W.  Queirazza  G. 《Hydrobiologia》1992,(1):501-517
Concentrations of the heavy metals Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn were measured in sea water, suspended matter, sediments and pore water samples collected in a coastal area of the middle Tyrrhenian Sea. Concentration factors between pore water (extracted from the first centimeter of the sediments) and the overlying sea water (taken 30 cm above the sea bed) were less than 1 for Cr, Cu and Pb, 1–10 for Cd and Ni, 10–100 for Fe and Co, 100–1000 for Mn, and 1–100 for Zn.The benthic fluxes of heavy metals at the sediment-water interface were measured directly using in situ benthic chambers and calculated using Fick's first law during two experimental periods, one in 1986 and the other in 1988. The fluxes of Cu, Ni, Pb and Zn varied significantly over time; this appeared to be related to their relatively low ( 10) concentration factors. From the benthic chamber experiments, metals with positive fluxes were in the order: Mn > Fe > Co > Cd, while those with negative fluxes were: Zn > Pb > Ni Cu. Fluxes calculated using Fick's Law were: positive – Mn > Fe > Zn (or Zn > Fe) > Ni > Co > Cd, negative fluxes Pb > Cu > Cr.Measured (benthic chamber) and calculated (Fick's first law) fluxes for Co, Cd, Mn, Pb and Fe were comparable within an order of magnitude, although less agreement was found for Cu, Ni and Zn. Removal of Ni and Zn at the sediment-water interface has been proposed to explain the fact that the measured and calculated fluxes have opposite directions for these metals.  相似文献   

6.
南京城市土壤重金属含量及其影响因素   总被引:82,自引:5,他引:77  
研究了南京城市土壤重金属含量、来源及其与土壤性质的关系。结果表明,南京城市土壤中,Fe、Ni、Co、V污染不明显,但受到了不同程度的Mn、Cr、Cu、Zn、Pb污染,其中:Pb污染非常严重;重金属在土壤剖面分布没有规律性;Fe、Ni、Co、V元素主要来源于原土壤物质,Cu、Zn、Pb、Cr元素主要来源于人为输入,Mn可能在不同的土壤中来源不同;Fe、Cr、Ni、Co、V元素含量之间均呈极显著正相关,Cu、Zn、Pb、Cr元素含量之间均呈极显著正相关。Fe、Co、V、Ni含量与粘粒含量、CEC呈极显著正相关;Cu、Zn、Pb含量与粘粒含量呈极显著负相关;Cu、Zn、Pb、Cr含量与有机碳呈极显著正相关,Pb含量与pH呈极显著正相关。  相似文献   

7.
Abstract

The chemical partitioning of Cu, Pb and Zn was examined in the soil profile of the woodland system in Keoladeo National Park, India using a five-step sequential extraction procedure (SEP). Metal partitioning was assessed in the soil up to a depth of 100cm with 25-cm intervals. The amount of metals obtained from the SEP exceeded pseudototal metal levels obtained from aqua regia digestion. The SEP results showed high preferential attachment of metals with Fe—Mn hydroxides. All the three metals showed least preferences to the exchangeable pool. The attachment of metals to the OM-S phase was also less, may be because of the low organic matter in the soil. In the case of Cu, the order of the fractions in terms of metal concentrations was Fe—Mn>RES>OM-S>CA>EXC and in the case of Pb the order was Fe—Mn>OM-S>RES>CA>EXC. Zn was different from Cu and Pb in showing higher affinity towards RES phase and the order of its concentration was RES>Fe—Mn>OM-S>EXC>CA. This suggests hydrous oxides of Fe—Mn as an important binding site for Cu and Pb, whereas silicate mineral matrix (RES phase) for Zn.  相似文献   

8.
人工饲养与野生川金丝猴体毛10种微量元素的含量及比较   总被引:2,自引:0,他引:2  
测定了秦岭人工饲养(10只)和野生(14只)川金丝猴体毛中的10种微量元素含量。锌、铁、铜、钙、镁5种元素采用火焰原子吸收法;锰、铬、铅采用石墨炉原子吸收法;铝采用等离子光谱;硒经硝解后采用原子吸收法测定。结果表明,铬、锰、镁、铅、锌和硒的含量,人工猴极显著或显著高于野生猴;铁含量,人工猴极显著低于野生猴;钙、铜和铝的含量,人工猴与野生猴无显著差异。以人类毛发10种微量元素的正常范围为参照,人工猴铅、铬、锰与锌4种含量均显著超出正常范围的上限,属于严重超量。这可能与金丝猴饲养过程中添加营养制剂有关。  相似文献   

9.
Copper,Lead, Cadmium,and Zinc Sorption By Waterlogged and Air-Dry Soil   总被引:1,自引:0,他引:1  
Competitive sorption of copper (Cu), lead (Pb), cadmium (Cd), and zinc (Zn) was studied in three soils of contrasting chemical and physical properties under air-dry and waterlogged conditions. Competitive sorption was determined using the standard batch technique using six solutions, each with Cu, Pb, Cd, and Zn concentrations of approximately 0, 2.5, 5, 10, 20, and 50?mg L?1Waterlogged soils tended to sorb higher amounts of added Cu, Pb, Zn and Cd relative to soils in the air-dry condition; however, this increase in sorption was generally not statistically (p<0.05) significant. The magnitude of sorption under both waterlogged and air-dry conditions was affected by the type and amount of soil materials involved in metal sorption processes, and competition between other metals for the sorption sites. Metal sorption was closely correlated with soil properties such as cation exchange capacity, organic carbon, and Fe and Mn hydrous oxides. Exchangeable Al may have markedly reduced metal sorption due to its strong affinity for the sorption sites, while increases in exchangeable Mn may have enhanced Zn and Cd sorption. Heavy metal sorption was best described as a combination of both specific and nonspecific interactions. The extractability of Cu, Pb, Cd, and Zn under waterlogged and air-dry conditions was also studied. Three solutions containing these metals were mixed with each soil to achieve a final concentration of 0, 50, and 500?mg kg?1. Each soil was extracted every 7 days using 1?M MgCl2 (pH 7) to determine metal extractability. Metal extractability initially decreased then increased due to waterlogging. The increased extractability of added metals was closely related to increased solubility of Fe and Mn suggesting that dissolution of Fe and Mn, oxides under reducing conditions caused a release of previously sorbed Cu, Pb, Cd, and Zn.  相似文献   

10.
For murine adenosine deaminase, we have determined that a single zinc or cobalt cofactor bound in a high affinity site is required for catalytic function while metal ions bound at an additional site(s) inhibit the enzyme. A catalytically inactive apoenzyme of murine adenosine deaminase was produced by dialysis in the presence of specific zinc chelators in an acidic buffer. This represents the first production of the apoenzyme and demonstrates a rigorous method for removing the occult cofactor. Restoration to the holoenzyme is achieved with stoichiometric amounts of either Zn2+ or Co2+ yielding at least 95% of initial activity. Far UV CD and fluorescence spectra are the same for both the apo- and holoenzyme, providing evidence that removal of the cofactor does not alter secondary or tertiary structure. The substrate binding site remains functional as determined by similar quenching measured by tryptophan fluorescence of apo- or holoenzyme upon mixing with the transition state analog, deoxycoformycin. Excess levels of adenosine or N6- methyladenosine incubated with the apoenzyme prior to the addition of metal prevent restoration, suggesting that the cofactor adds through the substrate binding cleft. The cations Ca2+, Cd2+, Cr2+, Cu+, Cu2+, Mn2+, Fe2+, Fe3+, Pb2+, or Mg2+ did not restore adenosine deaminase activity to the apoenzyme. Mn2+, Cu2+, and Zn2+ were found to be competitive inhibitors of the holoenzyme with respect to substrate and Cd2+ and Co2+ were noncompetitive inhibitors. Weak inhibition (Ki > or = 1000 microM) was noted for Ca2+, Fe2+, and Fe3+.  相似文献   

11.
The accumulation of 11 microelements (Fe, Zn, Cu, Co, Mn, Ni, Pb, Cd, Sr, Cr, and Se) by 7 wild onion species of the genus Allium was studied. A. flavescens Bess possesses the higher accumulating capability; it accumulates five of eleven microelements (Cr, Ni, Cu, Zn, and Se) with biological accumulation coefficient (BAC) exceeding 1 and also contains high levels of Fe, Co, and Mn. These features enable this species to be the most promising for the nutrition adjustment of human commons with above-mentioned microelements primarily with Cr, which content in 100 g onion leaves achieves 84% of commons. A. fistulosum L., A. odorum L., and broad-leaved A. nutans form specifically accumulate Cu, Zn, and Se. A. montanum Schmidt is characterized by the accumulation of Zn. A. angulosum and A. schoenoprasum are xharacterized by the accumulation of Se. The broad-leaved forms of A. schoenoprasum L., A. nutans L., and A. odorum L. compared with their narrow-leaved forms accumulate more amounts of Zn and Cu.  相似文献   

12.
SlyD is a Ni(II)-binding protein that contributes to nickel homeostasis in Escherichia coli. The C-terminal domain of SlyD contains a rich variety of metal-binding amino acids, suggesting broader metal binding capabilities, and previous work demonstrated that the protein can coordinate several types of first-row transition metals. However, the binding of SlyD to metals other than Ni(II) has not been previously characterized. To improve our understanding of the in vitro metal-binding activity of SlyD and how it correlates with the in vivo function of this protein, the interactions between SlyD and the series of biologically relevant transition metals [Mn(II), Fe(II), Co(II), Cu(I), and Zn(II)] were examined by using a combination of optical spectroscopy and mass spectrometry. Binding of SlyD to Mn(II) or Fe(II) ions was not detected, but the protein coordinates multiple ions of Co(II), Zn(II), and Cu(I) with appreciable affinity (K(D) values in or below the nanomolar range), highlighting the promiscuous nature of this protein. The order of affinities of SlyD for the metals examined is as follows: Mn(II) and Fe(II) < Co(II) < Ni(II) ~ Zn(II) ? Cu(I). Although the purified protein is unable to overcome the large thermodynamic preference for Cu(I) and exclude Zn(II) chelation in the presence of Ni(II), in vivo studies reveal a Ni(II)-specific function for the protein. Furthermore, these latter experiments support a specific role for SlyD as a [NiFe]-hydrogenase enzyme maturation factor. The implications of the divergence between the metal selectivity of SlyD in vitro and the specific activity in vivo are discussed.  相似文献   

13.
H Zhao  L Wu  T Chai  Y Zhang  J Tan  S Ma 《Journal of plant physiology》2012,169(13):1243-1252
Synchrotron radiation X-ray fluorescence (SRXRF) and inductively coupled plasma mass spectrometry were used to estimate major, minor and trace elements in Cu-, Zn- and Mn-treated Phytolacca americana. The effects of the addition of Cu, Zn and Mn on morphological parameters, such as root length, shoot height, and fresh and dry weights of shoots and roots, were also examined. In addition, the activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), guaiacol peroxidases (GPX) and catalase (CAT) and the expression of Fe-SOD, Cu/Zn-SOD, metallothionein-2 and glutathione S-transferase (GST) exposed to the highest amounts of Cu, Zn or Mn were detected. Our results confirmed the following: (1) Zn supplementation leads to chlorosis, disturbed elemental homeostasis and decreased concentrations of micro- and macroelements such as Fe, Mg, Mn, Ca and K. Cu competed with Fe, Mn and Zn uptake in plants supplemented with 25μM Cu. However, no antagonistic interactions took place between Cu, Zn, Mn and Fe uptake in plants supplemented with 100μM Cu. Mn supplementation at various concentrations had no negative effects on elemental deficits. Mn was co-located with high concentrations of Fe and Zn in mature leaves and the concentrations of macro elements were unchanged. (2) P. americana supplemented with increased concentrations of Zn and Cu exhibited lower biomass production and reduced plant growth. (3) When plants were supplemented with the highest Zn and Cu concentrations, symptoms of toxicity corresponded to decreased SOD or CAT activities and increased APX and GPX activities. However, Mn tolerance corresponded to increased SOD and CAT activities and decreased POD and APX activities. Our study revealed that heavy metals partially exert toxicity by disturbing the nutrient balance and modifying enzyme activities that induce damage in plants. However, P. americana has evolved hyper accumulating mechanisms to maintain elemental balance and redox homeostasis under excess Mn.  相似文献   

14.
为探讨油茶(Camellia oleifera)产地土壤和油茶果实中金属元素分布和富集特征,在油茶果实成熟期,对浙江5个油茶产地土壤及油茶果实中金属元素进行污染分析和富集能力评价.结果表明,浙江油茶产地土壤中Pb、Cr、Cd、As、Hg、Ni、Cu和Zn含量低于农用地土壤污染风险筛选值,综合污染等级为安全.个别产区常山...  相似文献   

15.
珍稀濒危植物矮牡丹体内矿质元素的研究   总被引:8,自引:0,他引:8  
采用原子吸收分光光度法测定了矮牡丹体内的10种矿质元素,即K、Mg、Mn、Fe、Ni、Zn、Cu、Cd、Cr、Pb。分析了矿质元素在矮牡丹体内的分布规律及矮牡丹对各种元素的富集能力。结果表明:在不同器官中的矿质元素含量有显著差异, K、Mg、Mn、Ni、Cd、Cr、Pb以叶中为高, Fe、Zn、Cu分别以根、茎、叶柄中含量最高;大多数元素在叶柄中含量最低。矮牡丹对K、Mg、Mn、Fe、Zn有较强的吸收富集能力,一般叶的富集系数较其它器官为高。元素间相关分析表明:Zn、Cd、Cr、Pb、Mn、Fe、Ni、Cu之间有显著的相关性, K、Mg之间的相关性显著。此外,土壤与植物体内元素含量表现出显著的相关性。  相似文献   

16.
The present study was carried out to find the effects of Pb acetate (10-50 mg/kg body wt) after oral administration on:
  1. The distribution of elements, such as Fe, Cu, Zn, and Mn;
  2. The activity of 6-amino levulenic acid dehydratase (δ-ALAD) and alkaline phosphatase (PAP); and
  3. On the level of reduced glutathione (GSH) in murine placenta.
Pb toxicity expressed on a dry-wt basis was reflected in terms of deficiency of δ-ALAD and PAP and enhanced content of GSH. Analysis of trace elements following Pb exposure showed low levels of Mn and Cu. Although Fe composition of placenta remained within normal range with increasing load of endogeneous Pb, Zn decline was not consistent after oral feeding of Pb acetate. Deficiency of PAP after Pb exposure did not correlate with the endogeneous levels of Pb or Zn therein, but correlated with endogeneous levels of Mn. Placental deficiencies of Cu and Mn have been related to the disturbed placental functions by Pb accumulation.  相似文献   

17.
There are limited data on essential nutrients in the whole blood of young children. As part of a longitudinal study of the impact on young children and the environment from the introduction of an organic Mn compound into unleaded gasoline in Australia, we have measured a suite of elements in whole blood. The children, aged between 6 and 31 months at recruitment, have been monitored at 6-month intervals for up to 5 years. Blood samples were analysed by inductively coupled plasma mass spectrometry for Ca, Mg, Fe, Mn, Cu, Zn and Pb. Mixed model analyses of 665 blood samples using backward elimination showed significant positive relationships between Ca, Mg and Zn and season, variable relationships with time, but no association with gender or traffic exposure. The elements Ca, Mg and Zn showed higher concentrations in summer compared with winter, whereas Fe and Pb showed lower concentrations in summer compared with winter. Concentrations of all elements except Fe showed significant effects over time: Ca, Cu, Mg, Pb and Mn showed decreases over time, whereas Zn showed an increase. The mixed model analyses with the individual elements as the dependent variable showed some interesting relationships and require further follow-up as some of these appear to conflict with pre-existing concepts, although the multi-element data on which these concepts are based are limited. The variance for blood Pb and blood Mn arising from the other elements was small with 0.5% in the case of blood Pb and 3.7% for blood Mn.  相似文献   

18.
The accumulation and biocycle of Cu, Pb, Zn and Mn elements were studied in Kandelia candel (L.) Druce mangrove community of Jiulong River Estuary of Fujian. The pool amounts of Cu, Pb, Zn and Mn elements in the forest soil (0~30 cm in depth) were 6.86, 4.23, 25.64 and 134. 67 g · m-2, respectively. The respective element contents ranged from in different parts of the plant, 1.85~6.97, 0.37~3.74, 16.0~25.2 and 140~1405 μg· g-1 of Cu, Pb, Zn and Mn. The pool amounts of elements in standing crop of the community were 87.98, 40. 34, 335.34 and 8006.99 mg · m-2 for Cu, Pb, Zn and Mn respectively. The pool amounts of Cu, Pb, Zn and Mn elements in residues were: 593.06, 49.27, 2450.79 and 43486.70 μg · m-2 respectively. The biocycle of the elements in the community were described as follows: Annual uptake of Cu was 10. 17, Pb 4.32, Zn 49. 14 and Mn 2268. 16 mg · m-2; Annual return of Cu was 2.21, Pb 0.70, Zn 18.63 and Mn 1574.98 mg· m-2; Annual retention of Cu was 7.96, Pb 3.62, Zn 30. 51 and Mn 693.18 mg · m-2. The turnover periods of Cu, Pb, Zn and Mn were 40, 58, 18 and 5 year, respectively. The absorption, utilatizion and cycle coefficients were in the order of Mn〉Zn〉Cu〉Pb.  相似文献   

19.
Differences in the accumulation of seven metallic elements, including micronutrients (Cu, Fe, Mn, Ni and Zn) and non-essential elements (Cd and Pb) among plant organs (leaves, roots and rhizomes) were examined in the seagrass Cymodocea nodosa. Samples were taken from two coastal bays (Catalonia, Western Mediterranean), with a total of nine sampling sites encompassing different levels of metal availability. Metal content was generally higher in uptake organs (leaves and roots) than in rhizomes. However, accumulation in leaves and roots varied between elements. While Cd, Mn and Zn preferentially accumulate in leaves, Fe and Pb accumulate in roots and Cu and Ni in both. There were common spatial (between sites) trends in Cd, Mn, Cu and Zn accumulation in the three organs. However, these spatial trends varied according to the organ considered in the case of Fe, Pb, and Ni. Therefore, assessment of within-plant variability is strongly recommended prior to the use of C. nodosa for biomonitoring purposes, at least for Fe, Pb, and Ni.  相似文献   

20.
Samples of rime/fog water and dust in the air were collected in order to compare concentrations of pollutants. Particular attention was paid to particles of heavy metals (Al, As, Cu, Fe, Pb, Ti and Zn). The concentrations of pollutants from the air are different in rime water and fog water. Both (fog) water and ice crystals fixed Ti, Cu, As and Pb ions minimally (less than 1%). Rime captured 11.6% Al, 9.3% Zn, 4.4% Fe and 91.2% Mn from the air. Fog water absorbed 9.8% Al, 9.0% Fe, 55.6% Mn, and 48.7% Zn from the air. Fog water absorbed Zn much better (48.7%) than rime (9.3%). Rime absorbed Mn better (91.2%) than fog water (55.6%).  相似文献   

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