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1.
Soil-to-plant transfer factors of 31 stable elements were determined by neutron activation analysis. The transfer factor is one of the important parameters used to estimate the internal radiation dose from radionuclides through food ingestion. In the present study, 12 species of agricultural plants such as root crops, fruit vegetables, green vegetables and pasture grasses, and their soils were collected from 150 farm fields in Aomori prefecture, Japan. The elements described are those that could be detected by this method, which include both essential and nonessential elements for plant growth. The concentrations of individual elements in the cultivated soil samples for each plant were similar in values and their standard deviations were within one order of magnitude, because of the relatively narrow geographic sampling area. The elements were classified into two groups, each having different transfer factor characteristics. In the first group of elements there was an inverse correlation between the transfer factors and the concentrations of elements in the soil, especially for Cl, K and Ca. In the second group, especially Sc and Co, however, the transfer factors were independent of the concentrations of elements in the soil.  相似文献   

2.
The intake of leafy vegetables in daily diet is very important to meet our nutritional needs. Vegetables provide the essential elements which are necessary and recommended for human growth. However, due to rapid industrialization and urbanization our environment becomes polluted and this affects the normal growth of agricultural products and composition of environmental species. The elemental concentrations present in the environmental samples are good indicators to assess the toxicological levels due to pollution affects. In the present work we have analysed several vegetable plant samples by instrumental neutron activation analysis to determine the elemental concentrations at major, minor and trace levels. The leafy vegetables like spinach, red leafy veagetable, pui, gourd leaf, lettuce and katoua were chosen as these are extensively consumed by local peple in eastern part of India. We have determined 15 elements in the above mentioned vegetable samples and some of these are essential elements and some are toxic elements. It was found that Na and K were present as major elements, Fe and Zn as minor elements and As, Ce, Cr, Co, La, Mo, Rb, Sc, Sm, Sr as trace elements. The concentration level of Cr was found to be higher than that of recommended value certified by WHO and National environment quality control for human consumption. The validation of our analytical results have been performed by the Z-score tests through the determination of concentrations of the elements of interest in certified reference materials.  相似文献   

3.
The elemental composition of peat depends on the plant residues from which the peat was formed. The concentrations of 45 elements were determined for five peat samples by plasma emission spectrometry. Literature data on the composition of three bogs was added. The elemental abundances of six rock or soil categories, the elemental compositions of several peat-forming plants, and the results of the elemental analyses of bog samples, were examined by the SIMCA method. A clear difference was found between fens and raised bogs. Factor analysis of the elemental compositions shows that the concentrations of most of the elements reflect their natural abundance in the surrounding region. Some concentrations are influenced by anthropogenic pollution, e.g. lead, and by plant metabolism. The cluster analysis together with the training sets shows the degree of the deposition of mineral material from adjacent rivers and the type of plant growth which formed the peat.  相似文献   

4.
We have performed spectroscopic analysis of the plasma generated by Nd:YAG laser irradiation of flesh and skin of fresh potatoes. From the spectra recorded with an Echelle spectrometer 11 minor elements have been identified. Their relative concentrations were estimated by comparing the measured spectra to the spectral radiance computed for a plasma in local thermal equilibrium. According the moderate plasma temperature of about 6500 K at the time of spectroscopic observation, the electrons are essentially generated by the ionization of the minor metal atoms, making plasma modeling possible although the organic elements may be out of equilibrium. Among the spectral lines selected for the analysis, the Na I 588.99 and 589.59 nm doublet was found to be partially self-absorbed allowing us to estimate the number density of sodium atoms. The value was found to agree with the number density predicted by the plasma model. As a result, the relative concentrations of the detected minor elements have been estimated for both the flesh and skin of the potatoes. Among these, aluminum and silicon were found to have relatively large mass fractions in the potato skin whereas their presence was not detected in the flesh. The present study shows that laser-induced breakdown spectroscopy is a promising tool to measure the elemental composition of fresh vegetables without any sample preparation.  相似文献   

5.
Seven trace elements were determined in milk formulas, powder milk and infant food. Instrumental neutron activation analysis was used for the analysis of Fe, Zn, Co, Cr and Rb, while As and Cu content was determined using radiochemical neutron activation analysis. Differences were found in the trace element content of foods of the same type. Milk formulas are comparable with human milk according to the results obtained for the elements analyzed. The samples of powder cow's milk presented similar concentrations of the elements studied. Liver with vegetables was found to have the highest Cu content. A meal prepared at home, made of beef and fresh vegetables showed a higher trace element content than its similar commercial one. An estimation of the daily intake of the elements analyzed was made and compared with minimum recommended daily ingestion.  相似文献   

6.
The elemental composition and antioxidant activity have been obtained for regional mushrooms species, wild and cultivated, from Dambovita County, Romania. A multivariate approach and data mining techniques (principal component analysis and cluster analysis, respectively) were applied in order to evaluate the correlation matrix for these parameters for both caps and stipes of mushrooms. The associations between metallic elements (i.e., Fe, Cu, Cd, Pb, Co, Ni, Zn, Mn, Cr, Na, K, Ca and Mg) correlated with antioxidant activity, total phenolics, and total flavonoids were carried out by using a full factorial linear design. The multivariate functional analysis revealed on associated accumulation of several elements in mushrooms. In the cluster analysis, the dataset was treated to appreciate the correlation between metals group (e.g., heavy metals, such as Fe, Cu, Cd, Pb, Co, Ni, Zn, Mn, Cr, and important nutritional elements, such as Na, K, Ca, and Mg). Fungal species with similar characteristics in terms of metal accumulation formed two distinctive clusters. From a point of view of the consumer, the content of Cd and especially Pb in the fruiting bodies of the analyzed mushrooms species may be considered elevated, so that mapping the risk is compulsory. Applying the chemometric tools in the sense mentioned above, as well as in helping the scientific research by optimizing the number of data points, was shown to be extremely useful.  相似文献   

7.
The concentration of five trace elements Cr, As, Pb, Rb and Sr in seven medicinal plants Garcinia indica, Ficus benghalensis, Flacartia Montana, Nyctanthes arbor-tristis, Morinda citrifolia, Ficus recemosa, Barringtonia acutangula and associated soils were analyzed using ICP-MS. In plant the elemental concentrations of Cr, Pb, Rb and Sr vary widely and in soil the elemental concentrations of Cr, As and Sr showed wide variation. Selective enrichment of elements Rb and Sr was observed in some plants. The soil to plant transfer ratio was significant for Sr. The results of these systematic investigations are presented and discussed in this paper.  相似文献   

8.
The objective of this study was to evaluate the influence of mining activity on elemental concentrations in kale grown around a mining area. Two sites studied are in the Iron Quadrangle, Minas Gerais, Brazil, considered one of the richest mineral-bearing regions in the world. One site is near mineral exploration activity and the other is an ecological area. A comparator site outside the Iron Quadrangle was also analyzed. This work focused on the determination of the elemental concentrations in kale applying the k0-instrumental neutron activation analysis. As the Brazilian legislation specifies values for soil only, the results for kale were compared to the literature values and it was found that the vegetable does not present any health risks.  相似文献   

9.
A total of 29 major and trace elements have been determined in 43 plant samples collected from the Xizang (Tibet) Plateau using INAA at a SLOWPOKE mini-reactor in order to study elemental background concentration values in Xizang plants. In this paper are reported elemental concentrations of different parts of the plants compared to average values of plants worldwide. The preliminary results suggest that nutritional, plant elements in this region are quite low indicative of a state of malnutrition, while the contents of Al, Ti, Cr and Ba are comparatively high. These findings indicate that the concentrations of most elements in the plants are mainly affected by local soil geochemical characteristics. Some variation in elemental distribution within the plants was also evident: in general, higher concentrations were found in stems compared to roots, and, differences for nutritional elements among the plant species were much greater than found for other elements.  相似文献   

10.
Instrumental neutron activation analysis using relative and k 0-based internal monostandard methods were employed for determination of concentrations of 12 elements in soil and tea plants collected from three different tea producing regions in India namely Assam, Darjeeling and Kangra. A total of 17 tea leaf samples along with corresponding soil samples were analyzed for elemental content. The obtained concentration data was used for the soil–plant elemental correlation studies. Positive correlation was observed between elemental concentrations of tea plants and the associated soil with Pearson correlation coefficient values in the range 0.6–0.9 for ten elements. Variations in transfer factor values were also observed according to the geo-chemical variation.  相似文献   

11.
Proton Induced X-ray Emission (PIXE) method is used for the determination of elemental concentrations in cancellous bone of human femoral head from five autopsies and seven patients with femoral neck broken. The specimen preparation and experimental procedure are described in detail. Using the t test, the results show that the concentrations of P, Ca, Fe, Cu, Sr in control group are higher than those in patient group, but the concentrations of S, K, Zn, Mn are not significantly different. The physiological functions of metallic elements in human bone are also discussed.  相似文献   

12.
The distribution of heavy and trace elements in coastal sediments was obtained by elemental analysis techniques such as INAA and GFAAS. The elemental concentrations were expressed in terms of enrichment factors derived by the elemental ratioing method, and evaluation was done by comparison to those found in SRMs. The associated sources of polluting elements were traced from their distribution patterns and, where applicable, related to the surrounding activities. Sample to sample variation was also taken into account to establish any correlative factors.  相似文献   

13.
This work shows that nuclear data and neutron flux parameters can be applied to calculate directly the elemental concentrations. Techniques for extracting neutron flux parameters pertaining to the irradiation positions and nuclear data pertaining to the isotopes concerned from measured reaction rates have been previously developed. This method is compared to the comparator and relative methods of activation analysis. The principles, advantages and disadvantages of each method and sources of errors are discussed. It also briefly discusses other factors such as accuracy and precision, sensitivity, detection limits and limit of quantitative determination. The three methods are applied to the analysis of five environmental reference materials. The concentrations of more than 20 elements are determined. The results show a good agreement with the certified and/or literature values.  相似文献   

14.
The review surveys the achievements of Russian scientists in mass-spectrometric analysis made in the past decade. Attention is focused on direct and indirect methods for the elemental analysis of solid and powdered materials. Among them are mass-spectrometric elemental analysis techniques with spark, laser, glow discharge, and inductively coupled plasma ionization. The applications of the above techniques to various areas of science, technology, and industry are described, in particular, the elemental analysis of nuclear technology materials, the determination of trace impurities in high-purity substances, some applications in medicine, biology, ecology, and basic research. Some achievements in the mass-spectrometric technique for the determination of the elemental composition of solid and powdered materials are considered. Some characteristics of methods are given: the range of the analyzed elements, errors in the determination of concentrations, and the limit of detection.  相似文献   

15.
Summary The objective of this study was to use synchrotron radiation total reflection X-ray fluorescence analysis (SR-TXRF) for the determination of metals and other elements in food available to the population in commercial establishments, in order to evaluate the risks of contamination by these products. The analyzed species were vegetables, leafy vegetables, fruits, cereal and grain. The results indicated that some species were contaminated by Cr, Cu, Zn and Pb with concentrations much higher than the reference values.  相似文献   

16.
17.
Summary The exogenous material that adheres to the leaf surface affects the elemental composition of the plant itself, thereby constituting one of the major error sources in plant analysis. The present work investigated the surface contamination of leaves from the Atlantic Forest. Instrumental neutron activation analysis (INAA) was applied to assess the efficiency of leaf EDTA-washing. Chemical element concentrations were corrected using Sc (soil tracer) since resuspended soil is the main source of contamination in leaves. As a result, EDTA-washing should be used mainly for the evaluation of terrigenous elements, while the Sc-corrected concentrations are considered satisfactory for the other elements.  相似文献   

18.
Using instrumental neutron activation analysis (INAA), graphite furnace atomic absorption spectrometry (GFAAS), flame atomic absorption spectrometry (FAAS) and combustion elemental analysis, green coffees of the Arabica species produced in crop year 1987/88 in Colombia, Costa Rica, Cuba, El Salvador, Mexico, Nicaragua, Panamá and Papua New Guinea were analysed for the elements Ba, Br, C, Ca, Co, Cr, Cu, Cs, Fe, H, K, La, Mg, Mn, N, Na, Rb, Sc, Sr and Zn. In accordance with the concentrations determined, the elements could be ranked into five groups: Sc (sub-ppb level); Br, Co, Cr, Cs and La (ppb level); Ba, Cu, Fe, Mn, Na, Rb, Sr and Zn (ppm level); Ca and Mg (%o level); and C, H, K and N (% level). On the basis of the results obtained, an attempt was made to establish the origin of the green coffee via its elemental composition. Among the investigated elements, manganese was found to be best suited as an indicator for this purpose. However, the elements C, Co, Cs, Na and Rb proved to be of interest too.  相似文献   

19.
The effectiveness of the neutralization process on heavy metals precipitated in sludge has been evaluated using instrumental neutron activation analysis (INAA) facilities at the South African Nuclear Energy Corporation (Necsa). The elemental concentrations of Th, Fe, Ag, Co, Cr, As, Au and K were reduced after the neutralization process with the exception of Mn and Sn which appeared to be enhanced by the neutralization process. Even though the neutralization process was targeted at the basic ferric arsenate compound, it was found to be effective in reducing other elemental concentrations. The variations in the geochemical compositions of the sulphidic ores during treatment at various stages also showed that physical processing stages do not significantly alter the elemental concentrations in the feed materials, however, the chemically active processing stages do. Also, the enhancement of the elements at the chemical stages depends on total quality control, where the application was not very repeatable the pattern of variation of elements at some stages was found to be irregular irrespective of the ore grade. The elements; Sn, Fe, Th, K, Au, Ag, As, Cr, and Co were enhanced in almost all the chemically active stages. Au was much more enhanced during flotation and bio-oxidation processes. Correlation analysis performed to determine the distribution patterns show that Fe, As, Ag and Co are geochemically associated and might be enriched simultaneously.  相似文献   

20.
In this study,an effort has been made to evaluate the pesticide residues in vegetables from western China. Fifty‐one pesticides, including organophosphorus, organochlorine, carbamate and pyrethroid, were detected in 369 commonly used vegetables by GC‐MS. Concentrations of organophosphorus pesticides were detected ranging from 0.0008 to 18.8200 mg/kg, among which organophosphorus pesticide concentrations exceeded their maximum residue levels (MRLs) in five samples. Carbamate and organochlorine pesticides were determined to have concentrations in the range of 0.0012–0.7928 mg/kg. The residual concentrations of carbamate pesticides in six samples and organochlorine pesticides in four samples exceeded their MRLs. The residual concentrations of five pyrethroid pesticides were within the range of 0.0016–6.0827 mg/kg and the pyrethroid residues in two samples exceeded their MRLs. The results revealed that pesticide residues in 70.73% of the vegetables samples were not detected, while in the rest of vegetables there were one or more pesticide residues and some even exceeded their MRLs, which would threaten the health of consumers. Our work provides significant information for the food safety regulations to control the excessive use of some pesticides on those kinds of vegetables from western China. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

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