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1.
Several potentially toxic trace elements, namely, Hg, Pb, Cd, As, Sb, Br and Se have been measured by INAA in combination with AAS techniques in the integrated diet representative of the inhabitants of Gujranwala, a highly industrialized city of Pakistan. The dietary intake values for these elements have been estimated from the prevailing concentration level in the summer and winter season diets, which reveals that present intake data are well within the reported WHO values and can be considered to be safe. Posslble sources of food contamination by the toxic elements and their adverse impacts on human heaith are briefly discussed.  相似文献   

2.
Dendrobium officinale is an important medicinal plant in traditional Chinese medicine. The consumption of D. officinale has increased rapidly in recent years due to the health awareness among Chinese people. The present study aimed to determine trace elements levels in 42 D. officinale samples and to utilize the elemental data for identifying the cultivation technique. Eighteen trace elements (B, V, Cr, As, Mn, Fe, Mo, Cu, Zn, Se, Sr, Sn, Ti, Al, Co, As Pb, Cd, and Bi) were determined by inductively coupled plasma–mass spectrometry. Of the 11 essential elements, the mean concentrations ranged from 30.6?µg?kg?1 (Mo) in D. officinale with greenhouse cultivation to 161?mg?kg?1 (Fe) in D. officinale with rock cultivation, and the contributions of Mn may exceed the dietary reference intake value by the uptake of 20?g of D. officinale. Of the seven toxic elements, the mean concentrations ranged from 3.29?µg?kg?1 (Bi) in the D. officinale with greenhouse cultivation to 342?mg?kg?1 (Al) in the D. officinale with rock cultivation, and the contributions of Al may exceed the provisional tolerable daily intake value by the uptake of 20?g of D. officinale. The concentrations of seven metals (Bi, Pb, Fe, Al, Cr, As, and Mo) were utilized to identify the cultivation technique of the analyzed D. officinale samples through linear discriminant analysis.  相似文献   

3.

The occurrence of 210Pb, 210Po, trace elements was assessed in a selection of berries on commercial sale in Italy. Data confirmed that berries might serve as an important source of essential elements. The 210Pb, 210Po concentrations found were higher than the reference values reported by UNSCEAR for roots and fruits in the world. There is no risk whatsoever from the intake of toxic elements as Al, As, Cd, Pb, Ni, Hg in berriberries analyzed; it is necessary, however, continuously monitored the levels of these elements to protect consumers against potential adverse health effects especially when consumed in large quantities.

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4.
Instrumental neutron activation analysis (INAA) and electro-thermal atomic absorption spectrometry (ETAAS) were employed to determine the toxic elements in fourteen fruits harvested in Pakistan. As, Br, Hg, Sb and Se were determined using INAA. Cadmium and Pb were determined using ETAAS. The intake levels of all toxic elements have been calculated. The data show that dates supply the maximum amount of most of the toxic elements. Peels of apple and pear have also been investigated and were found to contain higher concentration of toxic elements than their edible parts. The reliability of the techniques has been established by the use of standard reference materials. This study shows that all investigated fruits cultivated and consumed in Pakistan are safe for human consumption.  相似文献   

5.
Instrumental neutron activation analysis (INAA) and electro-thermal atomic absorption spectrometry (ETAAS) were employed to determine the toxic elements in fourteen fruits harvested in Pakistan. As, Br, Hg, Sb and Se were determined using INAA. Cadmium and Pb were determined using ETAAS. The intake levels of all toxic elements have been calculated. The data show that dates supply the maximum amount of most of the toxic elements. Peels of apple and pear have also been investigated and were found to contain higher concentration of toxic elements than their edible parts. The reliability of the techniques has been established by the use of standard reference materials. This study shows that all investigated fruits cultivated and consumed in Pakistan are safe for human consumption.  相似文献   

6.
The fruit bodies of wild-growing higher fungi (macromycetes), commonly called mushrooms, of various genera and species collected in localities with different geochemical features and man-made burden in the Czech Republic were analyzed by different modes of activation analysis. The elements Na, Mg, Al, S, Cl, K, Ti, V, Mn, Cu, Br, Ba and Dy were determined by short-term instrumental neutron activation analysis (INAA). Short-term epithermal INAA (ENAA) was used for determination of I and other elements, such as Rb, Ag, and U. The elements Na, K, Sc, Cr, Fe, Co, Cu, Zn, As, Se, Br, Rb, Ag, Cd, Sb, Cs, Ba, La, Ce, Sm, Eu, Hf, Au, Hg and Th were determined by long-term INAA, whereas long-term ENAA enabled determination of several other elements, such as Ni, Ta, W and U. The analytical possibilities of instrumental photon activation analysis (IPAA) using a microtron were also explored and found useful for determination of several additional elements, namely Sr, Y, Zr, Nb, and Pb. High concentrations of several essential and toxic trace elements found (up to hundreds of mg.g-1, dry mass) should be of concern in nutritional studies, because mushrooms form non-negligible part of diet in many countries, especially in Middle and East Europe.  相似文献   

7.
A pilot study was carried out to evaluate the scope of instrumental neutron activation analysis (INAA) for measuring the levels of selected elements in a few commonly consumed food items in Thailand. Several varieties of rice, beans, aquatic food items, vegetables and soybean products were bought from major distribution centers in Bangkok, Thailand. Samples were prepared according to the protocols prescribed by the nutritionist for food compositional analysis. Levels of As, Br, Ca, Cd, Cl, Cr, Cu, Fe, K, Mg, Mn, and Zn were measured by INAA using the irradiation and counting facilities available at the Thai Research Reactor with the maximum in-core thermal neutron flux of 3 × 1013 cm?2 s?1 of the Thailand Institute of Nuclear Technology in Bangkok. Selenium was determined by cyclic INAA using the Dalhousie University SLOWPOKE-2 Reactor facilities in Halifax, Canada at a thermal neutron flux of 2.5 × 1011 cm?2 s?1. Both cooked and uncooked foods were analyzed. The elemental composition of food products was found to depend significantly on the raw material as well as the preparation technique.  相似文献   

8.
Traditional Ayurvedic remedies are easily available nowadays not only in India, their country of origin, but also in Western countries. Some of these products contain high concentrations of potentially toxic elements as main or secondary ingredients, in addition to elements essential for human health; for these reasons, it is interesting to determine their elemental composition. In this study we assessed the concentrations of fifteen elements (Al, As, Ca, Cd, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Pb, Si and Zn) in five products of the Parpati family, a group of Ayurvedic medicines containing high concentrations of mercury, manufactured in various places in India. Concentrations were determined by inductively coupled plasma-optical emission spectrometry (ICP-OES) or (for Pb and Cd) by graphite furnace atomic absorption spectrometry (GF-AAS) after sample mineralization. We compared the calculated daily intake of each element with reference values, considering maximum tolerable intake levels or recommended nutrient amounts. The experimental results were treated with chemometric pattern recognition techniques. We found differences in the composition of products of the same denomination manufactured by different companies and strong correlations among groups of variables. As expected, the daily intake of mercury upon consumption of Parpati medicines largely exceeded the tolerable intake level of this element.  相似文献   

9.
The energy-dispersive X-ray fluorescence (EDXRF) spectroscopy has been used for the determination of essential and trace elements" contents of some twenty Nigerian medicinal plants. The accuracy and precision of the technique were assured by analyzing the European Community Bureau Reference Standard BCR 62 (Olive Leaves). Fourteen elements, namely K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Se, Br, Rb, Sr were detected with toxic heavy metal such as Cd, As, Pb, Hg were detected in the samples. The ranges of elemental concentrations varied from 7.7.104 to 1.6 mg/kg in the herbs. The results show that many of these plants contain elements of vital importance for human metabolism and prevention and healing of diseases.  相似文献   

10.
Portable instruments based on X-Ray Fluorescence Spectrometry (XRF) have the potential to assist in field-based studies, provided that the data produced are reliable. In this study, we evaluate the performance of two different types of XRF instrument (XOS prototype and Thermo Niton XL3t). These two XRF analysers were evaluated in a laboratory setting, and data were reported for 17 elements (As, Ba, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, Sn, Sr, Ti, V, and Zn). Samples analysed (n = 38) included ethnic herbal medicine products (HMPs), ethnic spices (ES), and cosmetic products (CPs). Comparison analyses were carried out using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). In general, results reported for Cd, Cu, and Pb by the XOS prototype analyser, using the non-metal mode, were negatively biased (5–95%) as compared to ICP-OES. In contrast, results reported for Pb, As, Cd, Cu and Zn by the Niton, using the soil mode, were positively biased, in some instances (Cd) by up to four orders of magnitude. While the sensitivity of both instruments was insufficient for reliably ‘quantifying’ toxic elements below 15 mg/kg, XRF was still capable of positively ‘detecting’ many elements at the low single-digit mg/kg levels. For semi-quantification estimates of contaminants at higher levels, and with limited sample preparation, both XRF instruments were deemed fit for the purpose. This study demonstrates that modern XRF instrumentation is valuable for characterising the elemental content of food, cosmetic, and medicinal products. The technology is particularly useful for rapidly screening large numbers of products (100’s per day) in the field, and quickly identifying those that may contain potentially hazardous levels of toxic elements. Toxic elements can be confirmed by examining the raw spectrum, and the limitations of factory-based calibration are generally manageable for field-based studies.  相似文献   

11.
Abstract

Herein the bioaccessibility of Mn, Cu, Zn, Cd, and Pb, selected from essential and toxic elements, was determined in commercially sold vegetable purees intended for infant and toddler consumption. Chemical fractionation studies using water, acetone, diethyl ether, chloroform:methanol, and n-hexane were employed to predict the importance of the protein and lipid parts of a matrix to assess the bioaccessibility data. In addition, in-vitro gastrointestinal digestion was performed to determine the bioaccessibility of the elements using a five level, three factor central composite design (CCD) to maximize the elemental solubility. The total elemental concentrations in all of the fractions were determined by inductively coupled plasma – mass spectrometry (ICP-MS). Based on the consumption of one jar of vegetable/rice-based baby food, Zn was 1.3% of the recommended dietary allowance and Mn was 4.2% of the adequate intake level, while Cu was almost 100% of the adequate intake level. Additionally, Pb was always below the detection limit and Cd was sometimes under the detection limit for the percent bioaccessibility. However, in some samples, Cd was as high as 80% of the tolerable weekly intake level depending on the body weight.  相似文献   

12.
中药中砷镉汞铅ICP-MS测定值的聚类分析   总被引:1,自引:0,他引:1  
聚类分析又称集群分析,它是研究“物与类聚”的一种数理统计方法,聚类分析可将一些观察对象依据某些特征加以归类。已经在生物学和医学分类问题[1]以及中药的鉴别与质量评价[2]中获得广泛应用。祁俊生等[3]利用因子分析和聚类分析探讨了微量元素含量与中药药性的相关性。梁逸曾  相似文献   

13.
Instrumental neutron activation analysis (INAA) have been used to determine As, Br, Hg, Sb and Se in combination with atomic absorption spectrometry (AAS) as a complementary technique for the quantification of Cd and Pb in jaggery, brown sugar, white sugar and molasses. All sugar cane products were collected from the local sugar cane industry of Pakistan. The highest concentration of these potentially toxic elements was quantified in molasses; however, molasses together with jaggery, brown sugar and white sugar contains trace amounts of all of these elements. Due to very low concentration of Cd it could only be detected in molasses. To evaluate the percentage contribution of these elements in the sugar cane products to the weekly recommended values, intakes on weekly consumption of 100 g of each item have also been calculated which follow the pattern Br>Se>Pb>Hg>As>Sb. The elevated Br contents may be attributed to the use of Br-containing chemicals for fumigation; however, these contents are well within the tolerance levels. The estimated weekly intake of all toxic elements is very low indicating that sugar cane products can be safely ingested as part of the diets.  相似文献   

14.
The elements Cd, Cr, Cu, Mn, Ni, Pb and Zn were determined in dust samples collected from air conditioner (AC) filters from 15 commercial sites of Lahore using flame atomic absorption spectroscopy (FAAS). The elements Cr, Mn and Zn were also determined using instrumental neutron activation analysis (INAA). The results obtained showed that higher amounts of these metals were measured in these dust samples than normally found in soil. This was especially true for Cd, Cu, Pb and Zn. Generally the amounts of Cd, Cr and Mn did not vary throughout the city of Lahore but the amounts of the traffic related Cu, Pb and Zn elements had the more variable ranges of 30–140, 30–230 and 74–2810 mg/kg respectively. The concentrations obtained for Cr, Mn and Zn by INAA were found to be higher than those obtained using FAAS. Analysis of the data obtained showed the digestion procedure employed to be the possible cause for this occurrence. It was also found that Mn was being over-estimated by INAA due to the interference from the Mg peak.  相似文献   

15.
A comparative evaluation of the applicability of different radionuclide sources for the determination of toxic elements in plants by ED-XRF is presented.238Pu or109Cd are suggested as most suitable single excitation sources in ED-XRF for monitoring investigations. More elements are determined with a combination of55F/109Cd(238Pu)/241Am. The results obtained by radionuclide ED-XRF analysis of different plants show that the method permits the reliable determination of Br, Ca, Fe, K, Mn, Rb, Sr and Zn in plant bioindicators. For toxic elements like As, Cd, Cu Cr, Hg, Ni, Se and Pb the detection limits of the method are not low enough.  相似文献   

16.
Trace and toxic elements in Certified Reference Material (CRM) made of Korean rice at the Korea Research Institute of Standards and Science have been analyzed by Instrumental Neutron Activation Analysis (INAA). Data intercomparison from the measurement with those of Atomic Absorption Spectrometry (AAS) and Induced Coupled Plasma Spectrometry (ICPS) has been studied. The powdered samples were sterilized at 1.5·106 rad in the bottles using a60Co source after sieving and spiking to specific elements such as As, Cd, Cr, Cu and Hg and then the homogeneity of samples was assessed. Rice flour (SRM 1568a) and standard solutions made by the National Institute of Standards Technology (NIST) were used to construct the calibration curves for the INAA and the chemical methods, respectively. The uncertainties and concentration of constituent elements were determined and the possibility of their use for analytical quality control was considered.  相似文献   

17.
Trifolium dubium is an edible plant that is utilized in traditional medicine for its anti-inflammatory and wound-healing properties. In this study, T. dubium was assessed to determine the elemental uptake by the plant as a function of soil characteristics. Across 10 geographic locations in KwaZulu-Natal, South Africa, the concentration of elements in T. dubium were found to be (descending order) Ca?>?Mg?>?Fe?>?Zn?>?Mn?>?Se?>?Ni?>?Cr?>?Cu?>?Co?>?Pb?>?Cd?>?As. The site had an influence on elemental uptake by the plant; however, accumulation or exclusion of elements from soil was controlled to meet physiological requirements. Soil chemical characteristics showed T. dubium grew in slightly acidic soils (pH – 6.15 to 6.68). The findings of this study show T. dubium to contain adequate concentrations of essential elements with undetectable levels of toxic metals, making the herb safe for human consumption and for use in traditional medicine. The plant can also contribute to poor communities by ameliorating food insecurity.  相似文献   

18.
This study reports the determination of trace essential (Co, Cr, Cu, Se, and Zn) and toxic (Al, As, Cd, Hg, and Pb) elements in greenhouse tomatoes, peppers, and cucumbers from supermarkets of Seoul, Busan, Gangneung, Daegu, Daejeon, and Gwangju, South Korea using inductively coupled plasma mass spectrometry, inductively coupled plasma optical emission spectroscopy, and direct mercury analysis. The methods were validated by linearity, limits of detection and quantification, precision, accuracy, and recovery measurements that provided satisfactory results in all cases. Among the essential trace elements, Zn was found to have the highest concentrations (0.84–2.5?mg/kg) followed by Cu (0.21–0.62?mg/kg) and Cr (0.01–0.06?mg/kg). The mean concentrations (mg/kg) of the toxic elements were in the order Al?>?Pb?>?As?>?Cd?>?Hg for tomatoes and cucumbers and Al?>?Pb?>?Cd?>?As?>?Hg for peppers; all were below the permissible limits set by World Health Organization for human consumption. The estimated dietary intake, target hazard quotients (THQs), and hazard indices of the samples were within safe levels. The combined THQ values for the toxic elements in the vegetables were from 0.002 to 0.012 with significant contribution from arsenic, aluminum, cadmium, and mercury. The results of this study show that trace and toxic elements in the analyzed vegetables do not impose any serious health harmful effects for the population upon consumption.  相似文献   

19.
The concentration of thirty-four elements each in Ghanaian dried tobacco leaves and snuff (powdered tobacco) have been determined using instrumental neutron activation analysis (INAA). The concentration of Hg, Cr, As and Cd in both set of samples were found to be in excess of WHO limits for drinking water, thus indicating potential toxicity of the samples. Cr, Cd, Sb and Cu were two to eight times high, whilst As and Hg were comparable in powdered tobacco and tobacco leaves. The aim of the study was to determine the pattern of elemental concentrations and the toxicological strengths in both tobacco leaves and tobacco powder. The results indicated that the toxicity of the snuff was higher than the tobacco. This indicated strongly that from the medical point of view, the level of toxic accumulation in users might be potentially high in the tobacco powder compared to the leaves. Thus, education of the Ghanaian public on the threshold value of toxic elements contained in both set of samples was suggested to safeguard users against these addictives.  相似文献   

20.
Earthworms were collected from agricultural fields in Admont, Graz, Piber and Gumpenstein, Austria. Six earthworm samples were investigated with INAA and with ICP-MS in parallel for the element concentrations of As, Ba, Cd, Co, Cr, Cu, Fe, Hg, Pb, Rb, Sb, Se and Zn. With both techniques 14 elements were analysed in a wide concentration range (ng/g to mg/g) GF-AAS and HG-AAS were used for verification of some element concentrations. A comparison of analytical results between INAA and ICP-MS was discussed. In general, good agreement between ICP-MS and INAA was obtained, the relative difference values of most of the elements are within ±20% range, however, a methodical error for the determination of Hg by ICP-MS was found.  相似文献   

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