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1.
Fourteen mineral and trace elements (Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sr and Zn) were determined in the herbs and their infusions consumed for medical purposes in Turkey such as chamomile (Matricaria chammomile L.), fennel (Foeniculum vulgare), linden (Tilia vulgaris), nettle (Urtica dioical), rosehip (Fr.Rosa caninae), sage (Salvia officinalis) and senna tea (Cassia anqustifolia). Microwave digestion procedure was applied under optimized conditions for dissolution of medicinal herbs. Element concentrations in the medicinal herbs and their infusions were determined by FAAS and ICP-AES. The accuracy and precision were verified against a GBW 07605 Poplar leaves and Tea certified reference material. The mineral and trace element content of medicinal herbs and their infusions showed a wide variability. However, distribution of the elements in the infusions is not high and it is nil especially for Cd, Co, Cr and Pb.  相似文献   

2.
Concentrations of Al, Cd, Cr, Cu, Mn, Ni, Pb, U and Zn were determined in vegetables (leafy vegetables, fruit, root, grain and cereal), derived products (sugar, coffee, manioc flour, wheat flour, corn flour, and pasta) and animal products (meat, fish, milk) most frequently consumed by adult inhabitants of Rio de Janeiro city. A total of 90 samples were analyzed using inductively coupled plasma mass spectrometry (ICPMS) as the principal method following sample dissolution by dry and wet ashing. Generally, highest contributions for the intake of micronutrients (Cu, Mn, Ni and Zn) arise from bean, rice and wheat flour consumption. Meat, cow milk and the flours, wheat and manioc, are major sources of Al, Cd, Pb and U intake. The daily intake of nine elements via foodstuffs was estimated as: 3.4x10(-4) mg of U, 1.8x10(-3) mg of Cd, 2.8x10(-2) mg of Pb, 2.3x10(-2) mg of Cr, 8.9x10(-2) mg of Ni, 1.12 mg of Cu, 2.5 mg of Mn, 3.5 mg of Al and 4.8 mg of Zn. The intake of toxic elements ranged between 2.7% (Cd) and 30% (U) of the provisional tolerable daily intake and reference dose values indicating that food consumption is, at present, no critical factor for the uptake of these toxic metals, in the population studied here. Concerning micronutrients, the recommended values of daily intake of Cu and Mn are conveniently supplied by the diet; however, for Cr and Zn they are lower than the recommend daily allowance. Due to high metal concentrations and consumption rates, black bean is the foodstuff that provided the highest ingestion rates of Cu, Mn, Ni and Zn (36-60% of the reference dose), being therefore a very important source of micronutrient supply.  相似文献   

3.
The trace metal (TM: Cd, Cu, Ni, Pb and Zn) budget (stocks and annual fluxes) was evaluated in a forest stand (silver fir, Abies alba Miller) in north-eastern France. Trace metal concentrations were measured in different tree compartments in order to assess TM partitioning and dynamics in the trees. Inputs included bulk deposition, estimated dry deposition and weathering. Outputs were leaching and biomass exportation. Atmospheric deposition was the main input flux. The estimated dry deposition accounted for about 40% of the total trace metal deposition. The relative importance of leaching (estimated by a lumped parameter water balance model, BILJOU) and net biomass uptake (harvesting) for ecosystem exportation depended on the element. Trace metal distribution between tree compartments (stem wood and bark, branches and needles) indicated that Pb was mainly stored in the stem, whereas Zn and Ni, and to a lesser extent Cd and Cu, were translocated to aerial parts of the trees and cycled in the ecosystem. For Zn and Ni, leaching was the main output flux (> 95% of the total output) and the plot budget (input-output) was negative, whereas for Pb the biomass net exportation represented 60% of the outputs and the budget was balanced. Cadmium and Cu had intermediate behaviours, with 18% and 30% of the total output relative to biomass exportation, respectively, and the budgets were negative. The net uptake by biomass was particularly important for Pb budgets, less so for Cd and Cu and not very important for Zn and Ni in such forest stands.  相似文献   

4.
In the present investigation, the flocculation of dissolved Cd, Cu, Ni, Pb, Mn and Zn with initial concentrations of 1, 2.5 and 5 mg/L in Tadjan River water during mixing with the Caspian Sea water has been studied in order to determine estuarine capacity to remove dissolved metals in the accidental contamination of the river. The flocculation process was investigated on a series of mixtures with salinities ranging from 0.1 to 11 p.p.t. The flocculation rates were indicative of the nonconservative behaviour of Cd, Cu, Ni, Pb, Mn and Zn during estuarine mixing. The order of the final flocculation rate of dissolved metals at 1, 2.5 and 5 mg/L of initial metal concentrations in the river water is as follows:Cu (99%)>Cd (95%)>Zn (88%)>Mn (85%)>Pb (83%)>Ni (73%), Cu(95.6%)>Pb(92.4%)>Cd (90%)>Zn(88.4%)>Mn (81.6%)>Ni(78.8%) and Cd (100%)>Cu(88%)>Ni (85.2%)>Pb (84%)>Zn (83.2%)>Mn (81.2%), respectively. The results also revealed that removal of dissolved metals is not influenced by pH changes and precipitation processes. The flocculation rates revealed that the overall dissolved metal pollution loads may be reduced to about 70% up to about more than 90% during estuarine mixing of Tadjan River with the Caspian Sea water.  相似文献   

5.
Metal removal by biological solubilization in three strongly contaminated sediments was carried out in a two-liter stirred bioreactor. Biological treatment yielded metal removal efficiencies in the range of 11-30%, 43-57%, 60-79%, 61-90%, 18-21%, 0-10% for Pb, Cu, Zn, Cd, Ni and Cr, respectively. The treated sediments were then rinsed with a NaCl solution (0.5 M), resulting in an increase by nearly 47% in Pb removal for the three sediments, while for other metals (Cu, Zn, Cd, Ni, Cr), the NaCl rinse did not seem to allow any significant increase in metal solubilization. A standard procedure of sequential selective extraction (SSE) was applied to the sediments before and after each treatment. With regard to Pb, Zn and Cd, the carbonate bound fractions (2/3 sediments) represented 18-42% of metals prior to treatment, while the iron and manganese oxides bound fraction constituted 39-60% of metals for the three sediments. Between 90 and 100% of Pb, Zn and Cd removed by the process came from the fractions bound to carbonates and from those bound to Fe and Mn oxides. The organic matter and sulfide bound fractions contained 65-72% of total Cu present before treatment and the process removed, on average, 63% Cu present in this fraction. In contrast, Ni and Cr were found mainly in the residual fractions (50-80%). Finally, this biological treatment did not solubilize Cr appreciably, while removal of Ni mostly originated from the carbonate and Fe/Mn oxides fractions (70-80%).  相似文献   

6.
Lead isotope ratios and Zn, Pb, Cu, Cd, Sb and Rb contents were measured in samples of rainwater collected over a period of 15 months from the Massif Central (France). Each sample, collected automatically at monthly intervals, represents a series of rainfall events. Rainwater chemistry was interpreted in terms of the chemical contributions from wet deposition and from different source regions for dust in the centre of France. Trace element concentrations in rainwater samples showed a wide range, particularly for Pb (1.30-465 microg/l), with variations decreasing for Cd (0.07-1.70 microg/l), Zn (1.00-54.00 microg/l), Cu (0.20-25.00 microg/l), Sb (approximately 0-0.33 microg/l) and Ni (approximately 0-15.00 microg/l). Trace element contents do not correlate with rainfall amount and no inter-element correlations are evident in the data. Lead is the most common trace metal found in the rainwater (mean value = 996 microg/m2/y) while Sb is the least common element measured (mean value = 1.12 microg/m2/y). The composition of rainwater collected from the Massif Central shows a range in Pb isotope ratios from 17.935 to 19.22 (206Pb/204Pb), 15.578 to 15.73 (207Pb/204Pb) and 37.559 to 38.606 (208Pb/204Pb). A five-component mixing model involving contributions from the natural background, gasoline inputs from industrial and agricultural activity and a source resulting from mining waste may be used to explain both the Pb isotope signature and the fluctuations in trace metal contents of Massif Central rainwater.  相似文献   

7.
In the northern part of Pisa Province (Tuscany, Italy), the use of lichens as both airborne trace element biomonitors and air quality bioindicators is described. The following elements were analysed in Xanthoria parietina: As, Cd, Cr, Ni, Pb, V, Zn and Hg, and the results are compared with those we previously obtained in Livorno Province (Tuscany) using the same lichen species. The results identify spots of different environmental metal contamination and air quality. Median values of Pb, V and Ni concentrations were much lower than those of Livorno Province, with maximum values even nine times lower. Arsenic contamination was also lower, while Cd, Hg and Zn levels were similar in the two areas. In Pisa Province, the highest levels of contamination were recorded for Zn, Pb, Cr and Ni, and a degree of agreement was found between air quality and metal concentrations in lichens. The air quality in Pisa Province is better than in Livorno Province, even if the different climatic and orographic features of the two areas may influence the presence of lichen species and thus an assessment of air quality.  相似文献   

8.
Sewage sludges obtained from seven wastewater treatment plants from the province of Salamanca, Spain, were periodically sampled to determine seasonal and time variation of their elemental composition over 2000 to 2002. The aim of this paper was to provide additional insight to evaluate the potential environmental impact following soil incorporation of these materials as amendments. Aqua regia extractable metals (pseudo total content) of Cd, Cr, Cu, Ni, Pb and Zn were determined and furthermore, the main chemical forms of metals within the sludge were evaluated using a five-step fractionation procedure. All the studied sludges displayed high fertility properties due to their richness of OC, P and K. Total mean concentrations of Cd, Cr, Cu, Ni, Pb and Zn in the sludges were within the regulation of the Spanish legislation. Using an multifactor analysis of variance, significant differences between Cr, Cu, Ni, Pb and Zn pseudo total contents (p<0.01) of sludges at different sites were found while the Cd content was statistically similar. Also significant differences were found between these pseudo total contents of heavy metals in samples collected along the time after three years (0.001相似文献   

9.
The nutritional status and trace element contamination of holm oak woodlands in Vesuvius National Park were assessed by analyses of Quercus ilex L. leaves and surrounding soils. The concentrations of Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, V and Zn were measured in 1-year-old leaves, and in the soils at 0-5 and 15-20 cm depths. The potentially available concentrations were also measured for the soils. The leaf element concentrations were similar to the Q. ilex chemical fingerprint, thus indicating a good nutritional status and the absence of short-term trace element depositions. Total K and V were more abundant in the deep soil layers than in the surface ones, whereas Cd and Pb showed higher values in the surface soils. This suggests that long-term soil accumulations of Cd and Pb are due to atmospheric input. The soil availabilities of Cd, Pb and Zn were high, and Cr availability was very low. A correlation between the available concentrations in the deep soil layers and leaf concentrations was found only for Zn.  相似文献   

10.
The content and intake of some trace elements (Pb, Cd, Ni, Hg, Cr) in meals, consumed by students attending the Faculty Cafeteria, were assessed. The study was carried out over 6 days of the 2nd week of February, 1993 and in three consecutive days of the second week of May. In those periods 10453 and 4055 students attended the cafeteria, respectively. After recording the ingredients and the preparation and cooking methods, some edible portions of foods and dishes were collected, homogenised, lyophilised and kept in polyethylene bottles until analysis. We found few differences in food content and dietary intake of some (Ni and Cr) but not all trace elements between February and May. Higher levels of Pb, Cd, Ni, Cr were present in bread (21.5+/-14.0, 5.6+/-0.02, 55.6+/-1.7 and 66.9+/-0.1 microg/100 g of edible portion, respectively), followed by meat, filled pasta and cheese, whereas lower values were observed in vegetables and fruit. The highest Hg content was recorded in the pasta group. Among the most frequently consumed foods and meals, the highest levels of P, Pb, Cr, Hg, Ni were found in bread, meat and pasta. The calculation of mean trace element intake, corrected for leftovers, showed pasta, bread and meat as the main sources of Pb, Cd, Ni, Hg and Cr over the two periods. The estimated potential tolerated weekly intake (PTWI) resulted high for Pb and Cd and low for Hg. Finally, a large variability in trace element content between raw and cooked foods was observed. These results give valuable information on trace element content of foods to be used for preparation of meals at the Faculty cafeteria in different seasons.  相似文献   

11.
Concentrations of heavy metals such as Pb, Cd, Cu and Zn have been estimated in air particulates, water and food samples collected from different suburbs in Bombay during 1991–1994. The concentrations of these metals are translated into intake rates through inhalation and ingestion pathways. Results indicate the highest concentration of Pb and Cu are in pulses (green gram), Cd in leafy vegetables (amaranth) and Zn in meat. Root vegetables and fruits contained a lower concentration of these metals. Total intakes of Zn, Cu, Pb and Cd through air, water and food were 10500 μg/day, 1500 μg/day, 30 μg/day and 4.3 μg/day, respectively. Although the major contribution for the daily intake is the ingestion route, eventual uptake in the body stream is contributed through inhalation for Pb (41%) and Cd (16%) and ingestion for Cu (98.8%) and Zn (99.6%). The total intake of these elements through the duplicate diet study is 9500 μg/day for Zn, 1770 μg/day for Cu, 27 μg/day for Pb and 2.5 μg/day for Cd, respectively. The daily intake of these metals by the population of Bombay is well below the recommended dietary values.  相似文献   

12.
The Ni(2+) accumulation in batch mode from diluted solutions by gel beads of gellan gum (GG), alginate, kappa-carrageenan, agar, agarose, silica gel, polyacrylamide and two mixtures of GG+agar was investigated. All polymeric materials studied accumulated Ni(2+), but gel beads of GG were stable, easily obtainable and showed the highest Ni(2+) accumulation. The pH of the Ni(2+) solution was not critical for Ni(2+) accumulation. Accumulation of metals Cu(2+), Co(2+), Ni(2+), Pb(2+), Cd(2+) and Zn(2+) by GG gel beads reached the equilibrium after 24h. The removal of Pb(2+) and Cu(2+) from the aqueous solution was very efficient, with maximum metal uptake (q(max)) of 0.85 and 0.75 mmol/g dw GG, respectively. The general q(max) sequence was Pb>Cu>Ni approximately Zn=Co>Cd. In an equimolar metal mixture sorption experiment a clear reduction in accumulation was observed, except for Pb(2+) (30%). Heavy metals were desorbed with 100mM sodium citrate.  相似文献   

13.
The interaction of the trace metals Cu, Co, Zn, Ni, Pb and Cd with aluminium hydroxide precipitated in-situ from homogeneous solution was studied. Using total concentrations of 10−4 M Al, 10−7 M Zn, Cu, Co, Ni and 10−8 M Pb and Cd a removal of Zn, Cu, Pb, Cd from solution occurred together with Al, while Co and Ni concentrations in solution remained unchanged. The binding of Cu, Pb and Zn, Cd is in agreement with the effect predicted by using published (resp. evaluated for Zn and Cd), values for stability constants of surface complexes on preformed Al2O3-suspension. The different behaviour of these elements and of Co and Ni is expected from the hydrolysis and adsorption tendencies. The experimental conditions correspond to natural conditions in lake waters, where due to the pH-dependent solubility of aluminium hydroxide, in-situ precipitation may occur and cause the scavenging of trace elements.  相似文献   

14.
15.
Mineral fertilizers are sources of diffuse metal enrichment of agricultural soils. A survey of phosphate fertilizers (blends or raw) sold on the European market was undertaken to quantify metal input via fertilizers in European agricultural soils. A total of 196 phosphate fertilizer samples from 12 European countries were analyzed for trace metals. Analytical quality was controlled with a certified rock phosphate sample. The average metal concentrations (mg kg(-1)) in the fertilizers were 14.8 (Ni), 7.4 (Cd), 166 (Zn), 2.9 (Pb), 7.6 (As), and 89.5 (Cr). The trace metal concentrations were positively correlated with the P concentrations confirming that the rock phosphate was the major source of these elements. Lowest metal concentrations were generally found in samples from Scandinavian countries. At average P use, the trace metal input via fertilizers was similar to or even larger than the metal input via atmospheric deposition in European agricultural soils for Cd, As, and Cr, whereas the reverse was true for Zn, Ni, and Pb. The input of Cd in European agricultural soils has decreased from previously estimated values and the soil Cd mass balance was close to steady state on an average basis.  相似文献   

16.
In 1985, the collapse of the tailing dam in Chenzhou lead/zinc mine (Hunan, southern China) led to the spread of mining waste spills on the farmland along the Dong River. After the accident, an urgent soil cleaning up was carried out in some places. Seventeen years later, cereal (rice, maize, and sorghum), pulses (soybean, Adzuki bean, mung bean and peanut), vegetables (ipomoea, capsicum, taro and string bean) and the rooted soils were sampled at four sites: (1) the mining area (SZY), (2) the area still covered with the mining tailing spills (GYB), (3) the cleaned area from mining tailing spills (JTC), and (4) a background site (REF). Metal concentrations in the crops and soils were analyzed to evaluate the long-term effects of the spilled waste on the soil and the potential human exposure through food chains. The results showed that the physical-chemical properties of the soils obviously changed due to the different farming styles used by each individual farmer. Leaching effects and plant extraction of metals from some soils were quite weak. Certain soils were still heavily polluted with As, Cd, Zn, Pb and Cu. The contamination levels were in the order of GYB>SZY>JTC showing that the clean-up treatment was effective. The maximum allowable concentration (MAC) levels for Chinese agricultural soils were still highly exceeded, particularly for As and Cd (followed by Zn, Pb and Cu), with mean concentrations of 709 and 7.6 mg kg(-1), respectively. These concentrations exceed the MAC levels by 24 times for As and 13 times for Cd at GYB. Generally, the edible leaves or stems of crops were more heavily contaminated than seeds or fruits. Ipomoea was the most severely contaminated crop. The concentrations of Cd and Pb were 3.30 and 76.9 mg kg(-1) in ipomoea leaves at GYB, which exceeded the maximum permit levels (0.5 mg kg(-1) for Cd and 9 mg kg(-1) for Pb) by 6.6 and 8.5 times, respectively. Taro (+skin) could accumulate high concentrations of Zn and Cd in the edible stem, and rice and capsicum had high Cd concentration in the edible parts. However, the toxic element concentrations in maize, sorghum, Adzuki bean, soybean and mung bean remained lower than the threshold levels. The bio-accumulation factors (BAFs) of crops were in the order: Cd>Zn>Cu>Pb>As. BAF was typically lower in the edible seeds or fruits than in stems and leaves. The accumulation effect strongly depends on the crop's physiological properties, the mobility, of the metals, and the availability of metals in soils but not entirely on the total element concentrations in the soils. Even so, the estimated daily intake amount of Cu, Zn, Cd, and Pb from the crops grown in the affected three sites and arsenic at SZY and GYB exceeded the RDA (Recommended dietary allowance) levels. Subsequently, the crops grown in Chenzhou Pb/Zn mine waste affected area might have a hazardous effect on the consumer's health. This area still needs effective measures to cure the As, Cd, Pb, Zn and Cu contamination.  相似文献   

17.
Cereals, especially rice, are a major source of cadmium (Cd) intake for general Japanese populations. In 1998-2000, rice (polished), bread (loaf), noodle and (wheat) flour samples (4113 samples in total) were collected in 63 cities all over Japan, and analyzed for Cd by inductively-coupled plasma mass spectrometry. Another pollutant element of lead (Pb) was determined in parallel. The grand geometric mean for Cd in polished raw (uncooked) rice was 50 ng/g, whereas it was 19 ng/g for flour. The value for Pb was 2-3 ng/g in rice and flour. Calculation for daily Cd intake via rice, taking advantage of the present findings on Cd contents in rice and wheat together with administrative area-specific daily consumptions of rice and wheat showed that Cd via rice is much more than Cd via wheat and that Cd via rice is highest in an area alongside the sea of Japan among the whole country, the observation being in agreement with the results from a previous food duplicate-based field survey.  相似文献   

18.
Bioaccumulation of Cd, Co, Cu, Ni, Pb and Zn in the Antarctic calanoid copepod Metridia gerlachei (Giesbrecht 1902) was investigated during a cruise of RV 'Polarstern' to the Weddell Sea, primarily to provide information on accumulation strategies for the metals tested. With the sole exception of Cd, the copepod accumulated metals during exposure and depurated them in uncontaminated seawater. The process of uptake and depuration was successfully described by a hyperbolic model, leading to significant estimations of the following experimental bioconcentration factors (BCFs): 210 (Co), 3430 (Cu), 3060 (Ni), 670 (Pb) and 2090 (Zn). Furthermore, we provide an approach to evaluate the sensitivity of Metridia gerlachei as a biomonitor of water-borne metals in the field; the results indicate minimal increments in ambient exposure concentrations of: 0.5 microg Cu l(-1), 0.8 microg Ni l(-1), 0.6 microg Pb l(-1) and 0.2 microg Zn l(-1), suggesting a high sensitivity of M. gerlachei for biomonitoring.  相似文献   

19.
Reed (Phragmites australis), a commonly used macrophyte in the wetlands constructed for water purification, was investigated as a new biosorbent for the removal of Cu(2+), Cd(2+), Ni(2+), Pb(2+) and Zn(2+) from aqueous solution. The metal adsorption capacity of reed biomass was improved significantly by water-wash, base- and acid-treatment. The maximum sorption of NaOH-pretreated reed biomass was observed near neutral pH for Cu(2+), Cd(2+), Ni(2+) and Zn(2+), while that for Pb(2+) was from an acidic range of pH 4.0 or higher. The maximum metal adsorption capacity on a molar basis assumed by Langmuir model was in the order of Cu(2+)>Ni(2+)>Cd(2+)>Zn(2+)>Pb(2+). Reed biosorbent showed a very high adsorption affinity value, which helps predict its high ability to adsorb heavy metals at low concentration. Desorption of heavy metals and regeneration of the biosorbent was attained simultaneously by acid elution. Even after three cycles of adsorption-elution, the adsorption capacity was regained completely and the desorption efficiency of metal was maintained at around 90%.  相似文献   

20.
Dietary intake of metals by Mumbai adult population   总被引:1,自引:0,他引:1  
Daily intake of 12 metals (Na, K, Ca, Cu, Zn, Fe, Mn, Mg, Pb, Cd, Co and Ni) by Mumbai adult population were assessed by analysing duplicate diet samples. These metals were determined by flame atomic absorption spectrophotometry (AAS) and stripping voltammetric techniques. A total of 250 diet samples containing 170 vegetarian diet and 80 non-vegetarian diet collected during April 2003 to March 2004 were analysed during this study. Daily dietary intakes of 2.4 g Na and 1.2 g K were observed for Mumbai adults. Daily dietary intakes of Ca, Cu, Zn, Fe, Mn and Mg were 367, 1.0, 6.3, 6.7, 2.0 and 304 mg, respectively. Pb, Cd, Co and Ni intakes by Mumbai adults were 32.3, 2.2, 2.2 and 108 microg/day, respectively. From this study it has been observed that the intake of toxic metals such as Pb, Cd and Ni is much lower than the tolerable daily intake derived from PTWI given by FAO/WHO and could not be considered harmful in this group of subjects. Daily intake of the studied 12 metals was found to be higher in non-vegetarian diet compared to the vegetarian diet (P<0.02, 0.01).  相似文献   

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