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1.
Inductively coupled plasma mass spectrometry (ICP-MS) was used to determine 18 trace elements (Ba, Be, Bi, Cd, Co, Cs, Cu, La, Li, Mn, Mo, Pb, Rb, Sb, Sn, Sr, Tl, and Zn) in 55 human milk samples from 46 healthy mothers collected during lactation periods extending to 293 days after birth. Se was quantified by hydride generation atomic absorption spectrometry (HG-AAS). To test the accuracy and the precision of the analytical procedure, milk powder reference materials (BCR 063 and BCR 150) were analyzed. The results obtained by ICP-MS and HG-AAS showed good agreement with the certified values. Whenever available, trace element concentrations determined in the human milk samples were compared to reliable literature data. The concentrations of Be (< 0.05 to 0.9 microgram/kg), Bi (< 0.09 to 2.0 micrograms/kg), Cs (1.7 to 7.7 micrograms/kg), La (< 0.05 to 3.7 micrograms/kg), Rb (440 to 1,620 micrograms/kg), and Tl (< 0.08 to 0.5 microgram/kg) are the first to be reported for human milk. The concentrations of the essential trace elements Cu (p < 0.005), Mn (p < 0.05), Mo (p < 0.0005), Se (p < 0.001), and Zn (p < 0.0005) significantly decreased and the concentrations of cobalt significantly increased (p < 0.005) in human milk during the course of lactation. All concentrations for the essential trace element tin in the human milk samples were below the method detection limit of 0.3 microgram/kg. Among the not essential and toxic elements-with the exception of Ba, Pb, and Tl-the trend toward lower concentrations with continuing lactation is much less pronounced than for the essential trace elements. With the exception of Se, the daily intakes of essential trace elements of fully breast-fed infants are considerably lower than dietary recommendations.  相似文献   

2.
With inductively coupled plasma-mass spectrometry (ICP-MS), the 18 trace elements Ba, (Be), (Bi), Cd, Co, Cs, Cu, La, Li, Mn, Mo, Pb, Rb, (Sb), (Sn), Sr, (Tl), and Zn were quantified in the digests of 13 formulas based on cow milk, of two formulas based on soy protein, of two milk powders, from which formulas were prepared, of two samples of Austrian cow milk, and in the water, with which the powders were suspended. Concentrations in parentheses were at or below the method detection limits in the formulas. The accuracy and precision of the analytical procedure tested with milk powder reference materials BCR 063 and BCR 150 were satisfactory. The concentrations of trace elements in the powders vary considerably from batch to batch. The ratios of high to low concentrations ranged from 1.1 to 4.8 and were higher for the essential trace elements Co, Cu, Mn, Mo, Sn, and Zn than for nonessential or toxic elements. The contribution of tap water from the water system of the city of Graz, Austria to the concentrations of trace elements in the formulas ranges from 45% for Pb to 0.2% for Rb and is negligible, for instance, for Cd, Cs, La, Mo, and Sn. Preformulas and follow-up formulas are partly supplemented with the essential trace elements Cu, Mn, and Zn and, therefore, concentrations of these trace elements in the formulas vary considerably. However, supplementation of a formula with a particular element must not necessarily result in higher concentrations compared to non-supplemented formulas. Concentrations of the essential elements were in the following ranges for preformulas, follow-up formulas, soy-based formulas (in microg/kg): Co, 8.3-11.2, 4.5-13, 5.0-5.7; Cu, 330-750, 27-730, 440-530; Mn, 33-580, 40-390, 440-530; Mo, 10-32, 9-39, 44-46; Sn, <0.44-3.8, <0.44-1.0, <0.44-5.8; Zn, 3340-11,380, 4120-7100, 5590-6,840. A preformula supplemented with Mn had a 10 times higher manganese concentration than preformulas without supplementation. Concentrations of all trace elements quantified were lower in cow milk than in formulas and do not meet the dietary requirements of infants.  相似文献   

3.
The preparation of hair for the determination of elements is a critical component of the analysis procedure. Open-beaker, closed-vessel microwave, and flowthrough microwave digestion are methods that have been used for sample preparation and are discussed. A new digestion method for use with inductively coupled plasma-mass spectrometry (ICP-MS) has been developed. The method uses 0.2 g of hair and 3 mL of concentrated nitric acid in an atmospheric pressure-low-temperature microwave digestion (APLTMD) system. This preparation method is useful in handling a large numbers of samples per day and may be adapted to hair sample weights ranging from 0.08 to 0.3 g. After digestion, samples are analyzed by ICP-MS to determine the concentration of Li, Be, B, Na, Mg, Al, P, S, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ge, As, Se, Rb, Sr, Zr, Mo, Pd, Ag, Cd, Sn, Sb, I, Cs, Ba, Pt, Au, Hg, Tl, Pb, Bi, Th, and U. Benefits of the APLTMD include reduced contamination and sample handling, and increased precision, reliability, and sample throughput.  相似文献   

4.
Electrothermal atomic absorption spectrophotometry (ETAAS), inductively coupled plasma mass spectrometry (ICP-MS) and neutron activation analysis (NAA) were used for the quantitative determination of 13 trace elements in urine and seven trace elements in whole blood of healthy unexposed British subjects living in three regions of the United Kingdom. Careful control of pre-analytical and analytical factors have enabled the results obtained from more than 200 individuals to be used in proposing reference intervals for the following elements; Al, As, Cd, Co, Cr, Cu, Hg, Mn, Mo, Ni, Pb, Se, Tl in urine, and Cd, Cr, Hg, Mn, Pb, Se and Tl in blood.  相似文献   

5.
A bulk cylindrical high-purity nickel ingot, with purity of more than 99.999 pct (5N) in mass, was obtained from the raw nickel with 99.95 pct (3N5) initial purity by virtue of double electron beam melting (EBM). A chemical analysis was performed by using glow discharge mass spectrometry (GDMS) analysis for all elements in the periodic table except carbon, nitrogen, and oxygen, which were tested by the high-performance combustion and fusion method. The major impurities B, Na, Al, Si, P, S, Ca, Ti, Cr, Fe, Cu, Co, Zn, As, Ag, Sb, and Pb showed an excellent removal effect with removal efficiency of more than 85 pct following the double EBMs. Li, Mg, Cl, K, V, Mn, Ga, Ge, Cd, Se, In, Sn, Tl, Au, and Pt were below the detection limit. No significant change in concentration was found for the refractory elements W, Mo, Ta, Nb, and Ir. Be, F, Sc, Se, Br, Rb, Sr, Zr, Y, Ru, Rh, Pd, Te, I, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Re, Os, Hg, Bi, Th, and U were not detectable following the purification as compared to the raw nickel. Gaseous impurities, C, N, O, especially for N, was removed sufficiently. Theoretical calculations for removal efficiency of impurity Fe based on the calculated vapor pressure, activity coefficient, and melt temperature were in good agreement with measured results, and the purification mechanism was ascribed to the evaporation of major impurities and subsequently evacuation by repetitive EBM.  相似文献   

6.
Results of more than ten years of experience in the determination of metals in mussels and algae collected in the North Sea and the Baltic Sea are presented. The various elements determined here are Hg, As, Se, Cd, Pb, Cu, Na, K, S, P, Zn, Mn, Fe, Sr, Ca, Ba, Mg, Tl, Ni, Co using techniques such as cold vapor AAS, INAA, hydride generation AAS, electrothermal AAS, ICP-AES, IDMS and stripping voltammetry. The results indicate the occurrence of three groups of elements with respect to long-term tendencies of their concentrations. In the first group, the concentrations in both mussels and algae varied in the same manner; in the second group no change was observed in either matrix while in the third group, the concentrations of elements changed in an opposite manner.  相似文献   

7.
The concentrations of ten trace elements, As. Br, Cd, Cu, Hg I, Mn, Se, Zn and V, have been determined in up to 27 species of higher fungi from several sites in Slovenia, Yugoslavia. Analyses were based on destructive neutron activation techniques. Data are presented and compared with the concentrations found in soils. Previously values were non-existent or scanty for these elements, so that the data represent typical levels for basidiomycetes. In addition to confirming high levels of mercury in many species, the survey also found that cadmium is accumulated to a surprising extent by most fungi, the average value being 5 ppm. Among other accumulations found was bromine by the genus Amanita, and selenium by the edible Boletus. Correlation analysis between all pairs of trace elements gave values for r of from 0.75 to 0.43 for 7 pairs (Cu and Hg, 0.75; Se and As, 0.69). As well as these features of biochemical interest, the values found and the pattern of accumulation suggest potential uses of fungi in environmental studies.  相似文献   

8.
When the secretion of pleural fluids exceeds their resorption, liquid (pleural effusion ) will accumulate between the visceral and parietal pleura. Pleural effusions derived from the liquid components of blood are expected to contain trace elements and may, as a sink for trace elements, deprive the body of needed essential elements upon their removal by medical intervention. Consequently, patients may be at risk of drifting into trace-element deficiencies. Because the literature is almost devoid of data about trace elements in effusions, the concentrations of 14 trace elements (Ba, Ca, Cd, Co, Cs, Cu, Mg, Mn, Mo, Pb, Rb, Sn, Sr, Zn) were determined simultaneously by inductively-coupled argon-plasma mass spectrometry (ICP-MS) in effusions from 17 patients. The median values for the concentrations of Rb (209 microgram/kg, range 104-334 microgram/kg) and Cs (1.5 micrograms/kg, range 0.8-2.4 microgram/kg) in the effusions were almost the same as in the sera. The concentrations of Mg (range 15-22 mg/kg), Ca range 52-91 mg/kg), Sr (range 12-37 micrograms/kg), and Ba (range 1.4-18.2 micrograms/kg) were consistently lower in the effusions than in the sera by 18% for Mg, 26% Ca 14% for Sr, and 88% for Ba (percentages based on median in serum as 100%). The concentrations of the essential trace elements Co (range 0.16-0.5 microgram/kg), Cu (130-902 micrograms/kg), Mn (0.2-2.2 micrograms/kg), Mo (0.4-1.5 micrograms/kg), Sn (0.4-1.2 micrograms/kg), and Zn (27-1931 micrograms/kg) in the effusions are generally lower (25-55% based on median) than in the corresponding sera, although a few effusions have higher concentrations of Co, Mn Mo, or Zn than in the sera. The concentrations of Cd (range 0.2-0.5 microgram/kg) in the effusions were approximately the same as in the sera for three patients, considerably lower than in the sera for four patients, and considerably higher for three patients. The concentrations for lead (range 0.6-45 micrograms/kg) in the effusions were generally much higher than in the sera. The effusions were not significantly contaminated with lead-rich erythrocytes. The concentrations of Ca, Cu, and Zn in the effusions correlated positively with the protein concentrations in the effusions. One kilogram of the effusions contain from 10-30% of the trace elements present in the entire volume of serum in circulation.  相似文献   

9.
To monitor the environmental contamination of heavy metals in Tuskegee Lake (TL) and National Forest Creek (NFC), Tuskegee, Alabama, adult crayfish muscle and exoskeleton and sediment samples were collected and analyzed for Hg, Pb, Cd, Cu, Co, Ni and Zn. In both TL and NFC crayfish Cu and Zn were not different in muscle and exoskeleton; however, Pb and Cd were significantly different. The Pb in exoskeleton and the Cu and Zn in muscle and exoskeleton of TL crayfish were significantly higher than that of NFC crayfish; however, Cd and Ni were not different between tissues or crayfish sources. Levels of Hg and Co were not detectable.  相似文献   

10.
Elemental analysis of some herbal plants used in the control of diabetes has been done by the techniques of Neutron Activation Analysis (NAA) and Atomic Absorption Spectroscopy (AAS). The elements Mn, Na, K, Cl, Al, Cu, Co, Pb, Ni, Cr, Cd, Fe, Ca, Zn and Hg are found to be present in different plants in various proportions.  相似文献   

11.
ICP-MS测定地质样品中24种痕量元素干扰校正研究   总被引:1,自引:0,他引:1  
陈雪  刘烊  罗学辉  杨玉霞 《黄金》2013,34(4):74-77
研究并优化了ICP-MS同时测定地质样品中Ag、Ba、Be、Bi、Cd、Ce、Co、Cs、Cu、Cr、Li、Mo、Mn、Ni、Pb、Sb、Sc、Sr、Th、Tl、U、V、W、Zn 24种痕量元素的方法。通过选择适合的同位素,排除了同质异位素的干扰;通过降低CeO+/Ce+的比率,计算干扰校正方程,对难熔氧化物的干扰进行了校正;在线加入内标Rh,有效地抑制了基体效应。将该优化的方法经过国家一级地球化学标准物质验证(GSS-1、GSS-4、GSR-1、GSD-9、GSD-10),精密度好,准确度高,检出限大都低于0.1 ng/mL。大量实际样品的分析结果表明,该方法对于化探样品测试技术的提高有一定的实用性。  相似文献   

12.
Fourteen minor (Na, K, P, Fe) and trace (Br, Co, Cr, Cs, Hg, Rb, Sb, Se, Sr, Zn) elements have been determined in pre- and postoperative blood samples of 10 breast-cancer-affected. Indian women and compared with controls. The study showed elevation of Cr, Hg, Fe, Rb, Sb, and Zn and lowering of Se, K, P, and Sr contents in the blood of cancer patients. Most elemental contents in pre- and postoperative stages remain unaltered except Br, Co, and Sb. Statistical significance of Fe, Se, Zn, and Hg levels has been tested by box plots. Lowering of Se in blood (-54.4%) is correlated with its enhancement in cancerous breast tissue (94.7%) of various clinical stages. Se/Zn and Se/Fe ratios are lowered in the blood of cancer patients, whereas Na/K ratio is only marginally enhanced. An attempt has been made to correlate Se levels with the dietary intake and breast cancer risk vis-a-vis American and Japanese women.  相似文献   

13.
A duplicate diet meal study was carried out with a group of university students living in a hostel, in order to estimate the intake of Zn, Cd, Co, Cu, Fe, Mn, Ni and Pb. Zn, Cu, Fe, Mn and Ni were determined by flame atomic absorption spectrophotometry and Cd, Co and Pb by graphite furnace atomic absorption spectrophotometry after a nitric acid wet digestion procedure. The estimated intake values from the contents of breakfast, lunch, dinner and drinks were compared with the values of the Provisional Tolerable Daily Intake (PTDI) in the case of Cd and Pb, Recommended Dietary Allowances (RDA) of Co, Fe and Zn and Estimated Safe and Adequate Dietetic Daily Intake (ESADDI) of Cu and Mn. Neither excessive intake of Pb and Cd nor deficiencies in Zn, Co, Fe, Mn or Ni were observed, but Cu intake was lower than the ESADDI.  相似文献   

14.
采用在密闭塑料瓶中硝酸、氢氟酸常温常压分解样品,系统分析了样品中痕量杂质元素V、Ti、Mo、Fe、Sb、Pb、As、Co、Mg、Ca、Mn、Al、Sn、Na、K、Ni、Cr、Cd、Si、Cu、P、Bi的光谱干扰情况及钨酸沉淀分离基体后各元素的回收率情况,最终确立了电感耦合等离子体原子发射光谱(ICP-AES)法测定钨产品中痕量元素的方法。V、Ti由于基本不受基体干扰,钨酸沉淀分离基体后回收率较低,采用在校准曲线中补加基体的方法对其进行测定,其中V的测定下限为5.2μg/g,Ti的测定下限1.3μg/g:Co、Mg、Ca、Mn、Al、Na、K、Ni、Cr、Cd、Si、Cu、Pb、Sn、As、Sb、Bi等元素,受钨基体干扰比较严重,采用钨酸沉淀分离基体后,回收率均在90.0%以上,故采用沉淀分离基体,水标直接测定,各元素的测定下限均在0.10~6.7μg/g之间:而对于受钨基体严重干扰,而且钨酸沉淀分离基体后回收率较低的Fe、Mo、P3元素,目前没有很好的解决方案。此方法为解决钨产品中痕量杂质元素测定提供了一种有效可行的方法。  相似文献   

15.
为探究贵州丹寨县铅锌矿区矿业活动对土壤系统运转对环境影响,以丹寨县兴仁镇铅锌矿区土壤为研究对象,采集小流域内河流周边不同土地利用类型土壤表层(0~20cm)的样品,分析测定土壤中Cu、Cd、Pb、Zn、Mn、Hg、As 7种重金属含量。应用单因子污染指数法、内梅罗综合污染指数法、地质累积指数法、潜在生态指数法对矿区不同土壤层重金属进行污染程度和潜在生态风险进行评价。结果表明,0~10cm土壤中Cu、Cd、Pb、Zn、Mn、Hg、As含量分别是贵州省土壤背景值的0.65、5.13、1.74、2.45、0.59、5.08、0.27倍。10~20cm土壤中Cu、Cd、Pb、Zn、Mn、Hg、As含量分别是贵州省土壤背景值的0.71、3.11、1.18、2.21、0.65、4.88、0.21倍。不同小流域与不同深度土层危害程度有所差异,通过评价结果得出研究区主要污染重金属元素为Cd、Hg,土壤重金属处于中等及以上潜在生态危害程度。  相似文献   

16.
采用NaOH熔融分解样品,热水浸取熔融物,加入酒石酸络合钨、钼、铌、钽等易水解元素,然后在盐酸介质中用电感耦合等离子体原子发射光谱法同时测定铝土矿中Al2O3、SiO2、Fe2O3、TiO2、CaO、MgO、K2O、P2O5、MnO、Ga、Ge、V、Li、Cr、Nb、Ta、Sr、Zr、Hf、Sc、La、As、B、Ba、Be、Bi、Cd、Co、Cu、Ni、Pb、Sb、Sn、Tl、Zn、Mo、Se、In、Te和W等40种组分。通过筛选分析谱线、合理设置背景扣除位置及干扰元素校正系数,避免了光谱干扰。方法检出限为 0.05~0.85 μg/g。用本法测定了铝土矿国家标准物质和实际样品中的上述40种组分,测定值与认定值或化学法测定值吻合,测定结果的相对标准偏差(RSD,n=11)在0.15%~5.9%之间。  相似文献   

17.
Geochemical subsoil data obtained from China and European laboratories have been compared in this study. 787 C horizon subsoil samples from FOREGS (Forum of European Geological Surveys) geochemical baselines mapping project were sent to China's IGGE (Institute of Geophysical and Geochemical Exploration) laboratory and composited to 190 samples according to the 160 km × 160 km GNT (Global Terrestrial Network) cells. In addition to the FOREGS elemental analysis package, Au, Pt, Pd, B, Ge, Br, Cl, Se, N, Li and F were also analyzed by using the IGGE's 76 element analytical scheme. Geochemical data statistics, scatter plotting, and geochemical map compilation techniques have been employed to investigate differences between FOREGS and IGGE analytical results. The results of two datasets, the IGGE's analysis data for composited samples, and the FOREGS average data of samples in each GNT cell, agree extremely well for about 23 elements, viz: SiO2, Sr, Al2O3, Zr, Ba, Fe2O3, Ti, Rb, Mn, Gd, CaO, Ga, MgO, P, Pb, Na2O, Y, Th, As, U Sc, Cr, and Co. There are slight differences between-laboratory biases shown as proportional errors between the datasets for Ni, K2O, Tb, Tl, Cu, S, Sm, La, Ce, Pr, Nd, Eu, Ho, Er, Tm, Yb, Lu, Ta, Nb, Hf, and Dy. For Cd, Cs, Be, Sb, In, Mo, I, Sn, and Te, the correlation of the two datasets and the similarity of the geochemical maps are fairly good, but obvious biases exist between the two datasets at values near detection limits.  相似文献   

18.
钽酸锂中杂质元素含量是划分产品等级的重要参数。样品中加入硝酸和氢氟酸后用微波消解法溶解样品,在线加入1.00 μg/mL的Cs内标溶液后,在H2动态反应池模式下测定Ca、Fe、As、Se,在标准模式下测定其余元素,建立了微波消解-电感耦合等离子体质谱法(ICP-MS)测定钽酸锂中Be、B、Na、Mg、Al、K、Ca、Ti、V、Cr、Mn、Fe、Co、Ni、Cu、Zn、As、Se、Zr、Nb、Mo、Cd、Sb、Ba、Hf、W、Pb和Bi共28种杂质元素含量的方法。对溶样方法进行了优化,确定选用2 mL硝酸-2 mL氢氟酸体系于190 ℃保温120 min的方式微波消解样品。在优化的实验条件下,28种元素的检出限为0.003~0.37 μg/g,定量限为0.01~0.74 μg/g。采用实验方法测定市售钽酸锂样品中Mg、Al、Ca、Ti等28种杂质元素含量,测定结果的相对标准偏差(n=7)均小于5%,加标回收率为87%~112%。采用电感耦合等离子体原子发射光谱法(ICP-AES)对样品中Fe含量进行测定,测定结果与实验方法基本一致。  相似文献   

19.
采用电感耦合等离子体原子发射光谱(ICP-AES)法直接测定煤与焦炭中Si,P,Al,V,Cr,Cd,Pb,Cu,Co,Ni,Zn,K,Na,Fe,Ca,Mg,Mn,Ti 18种元素。样品被灰化后取一定量灰样,用氢氧化钠熔融,热水和盐酸浸取,溶液用于测定Si和P,得到煤或焦炭灰中Si,P含量。另取灰化后的全部灰样,用高氯酸和氢氟酸溶解并加热至赶尽高氯酸,用稀硝酸溶解,溶液用于测定Al,V,Cr,Cd,Pb,Cu,Co,Ni,Zn,K,Na,Fe,Ca,Mg,Mn和Ti,得到煤或焦炭中16个元素含量。Si和  相似文献   

20.
A comparative survey of trace elements in hair samples from three different regions of the world was carried out. The concentrations of the same trace elements in tissues from infants and adults from Glasgow are also presented. It was found that the Se levels in hair samples from Iceland are significantly lower than the levels found for the Glasgow area. The level of Hg was in the same range as that for the Glasgow area and the As level is much lower in Iceland. Comparison of the levels of Hg, As, and Se in hair samples from Iran and Glasgow revealed significantly lower levels of these trace elements in samples from Iran, but the Cu levels were similar. Comparison of adult and infant levels of Se and Cu revealed fetal storage of Cu in the livers of infants. Arsenic levels were higher in adult tissues. In the study of the interaction among trace elements in human tissues, a positive correlation between Hg and Cu in liver samples from the Glasgow area and hair samples from Iran was found. A positive correlation between Se and As was also found in spleen and lung tissues.  相似文献   

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