Trace elements in the atmosphere.

The distribution and behaviour of particulate trace elements in the atmosphere have been studied by continuous measurements for 5 years at seven non-urban sites in the United Kingdom. Samples have been taken regularly of airborne dust, rainwater and dry deposition: these have been analysed for up to 36 elements. Concentrations of trace elements vary considerably between sites but the relative concentrations are among uniform: this suggests similarity of origin or good atmospheric mixing. By comparing the relative concentrations with those in soil it is possible to differentiate between trace elements that are derived from soil and those that may be attributed to industrial activity. This classification is supported by estimates of the particle sizes in air. The deposition of trace elements can be related to the concentrations presnet in soil and to the annual removal by crops. Retrospective analyses of stored samples from one site describe the history of trace element concentrations in air since 1957. The sea surface is considered as a possible source of atmospheric trace elements.     

Preliminary study on the relationship between osteoporosis and trace elements with rat models

Thirty rats were divided randomly into five groups and fed with different feeds. They were killed after 2 mo. Right thighs of these rats were taken as samples. Bone mineral densities of these samples were measured by the double-energy x-ray bone mineral densitometer, and trace elements contents of the samples were analyzed by neutron activation analysis. Results of the experiments showed that some elements were well correlated with others, and there were obvious variances between some elements of the normal group and those of other four groups.     

Determination of trace elements in normal and diabetic whole blood by neutron activation analysis

Biological Trace Element Research - The concentration of 10 trace elements in samples of normal and diabetic whole blood were investigated by neutron activation analysis (NAA). Instrumental NAA...     

Charged-particle activation analysis of biological material

Charged-particle activation analysis offers a number of interesting possibilities for the determination of trace elements in biological material. It allows the determination of those elements that are difficult or impossible to determine by neutron activation, such as Li, B, Al, Si, V, Cr, Ni, Cd, Sn, Tl, and Pb. Up to now, protons have been successfully applied to samples of both vegetale and human origin. A number of difficulties have to be overcome, one of which is excessive heating of the samples owing to the limited range of the charged particles, thus giving rise to a high energy deposition in a small volume. Moreover, the sample composition has to be known to allow the calculation of the range of the particles. an interesting alternative has been proposed using an internal standard together with a standard additions procedure. Proton activation analysis was tested on a wide variety of reference materials, giving evidence that accurate results can be obtained for many trace elements, even when applying a purely instrumental method. Thus, the method can also be applied in the certification of reference materials, since nuclear methods are independent of chemical properties of the sample.     

Determination of trace elements in tissue of human uterine cancer by instrumental neutron activation analysis

In this article, the low-temperature freeze-drying pretreated technique and instrumental neutron activation analysis were used to determine 29 trace elements in samples of human uterine cancer tissue. The content of these trace elements in uterine cancer tissue was compared with that in cervicitis tissue and in healthy tissue, respectively. Preliminary results indicated that significant differences in contents of Au, I, and Se were observed in these tissues.     

Trace element content in breasts with fibrocystic disease

The trace elements antimony, bromine, cesium, cobalt, iron, rubidium, scandium, strontium and zinc were determined by instrumental neutron activation analysis in breast tissue samples with fibrocystic disease and in samples with fibroadenoma tumors. The histological lesions of each breast sample with fibrocystic disease were recorded, and a statistical analysis of the lesions in combination with the determined trace elements was carried out. The results showed that the element mean values in fibroadenoma tumors are higher than those of fibrocystic disease. Some other remarkable results of statistical examination are also presented.     

Instrumental neutron activation analysis of rib bone samples and of bone reference materials

The instrumental neutron activation analysis method was used for the determination of trace elements in rib bone samples taken from autopsies of accident victims. The elements Br, Ca, Cl, Cr, Fe, Mg, Mn, Na, P, Sr, Rb, and Zn were determined in cortical tissues by using short and long irradiations with thermal neutron flux of the IEA-R1m nuclear reactor. The reference materials NIST SRM 1400 Bone Ash and NIST SRM 1486 Bone Meal were also analyzed in order to evaluate the precision and the accuracy of the results. It was verified that lyophilization is the most convenient process for drying bone samples because it does not cause any element losses. Comparisons were made between the results obtained for rib samples and the literature values as well as between the results obtained for different ribs from a single individual and for bones from different individuals.     

INAA and PIXE of Atmospheric and Combustion Aerosols

Using instrumental neutron activation analyses and photoninduced x-ray emission techniques for analysis of size-fractionated atmospheric and combustion aerosols and other emission samples arising from fluidized-bed combustion of North Bohemian lignites up to 42 elements were determined in all sample types. This allowed the evaluation of element enrichment, time trends, and interelement correlations and the performance of factor analysis of various fractions of atmospheric aerosols. The data obtained on mass and element size distributions of aerosols and emission samples obtained upon lignite combustion in an experimental scale atmospheric fluidized-bed combustor without and with added hydrated lime and limestone were used to elucidate the mechanism of abatement of toxic trace and matrix elements from flue gas.     

INAA of trace elements in colorectal cancer patients

The concentration of trace elements in samples of both colorectal cancer tumors and normal tissues of a Mexican population were irradiated for 30 s and 4 h and their elemental content were measured by instrumental neutron activation analysis. Ca, Cu, Co, I, Mg, Se, Fe, Zn, Hg, Ba, and Cr were analyzed. Alterations in Co, Fe, I, and Ba were found in tumors with respect to normal tissues.     

Air quality status in Kinshasa as determined by instrumental neutron activation analysis,atomic absorption spectrometry,and ion-exchange chromatography

Three independent analytical techniques: instrumental neutron activation analysis, atomic absorption spectrometry, and ion-exchange chromatography were applied to airborne particulates collected on filters, and to atmospheric acid gases collected in carbonate buffer solutions. Twenty trace elements and seven acid gases and acid aerosols were determined. Results were compared with those observed elsewhere and showed that air pollution is low in Kinshasa and should not cause anxiety. The main known sources of pollutants are vehile exhaust and aeolian processes on stripped soils.     

Trace elements in rock salt and their bioavailability estimated from solubility in acid

In this study, 18 partly commercially available samples of rock salt from Austria, Germany, Pakistan, Poland, Switzerland, and Ukraine were investigated with respect to their content of trace elements using instrumental neutron activation analysis. Elements detected were Al, Ba, Br, Ca, Ce, Cl, Co, Cr, Cs, Eu, Fe, Hf, La, Mn, Na, Rb, Sb, Sc, Sm, Sr, Ta, Tb, Th, and Zn, some of them only in individual cases. An estimation of the bioavailability of these trace elements was performed by dissolving an equivalent of the sodium chloride samples in diluted hydrochloric acid (simulating stomach acid), filtering off the insoluble components, and analyzing the evaporated filtrate. It could be shown that in most cases bioactive trace elements like Fe can be found in rock salt in the form of almost insoluble compounds and are therefore not significantly bioavailable, whereas thorium, for example, was partly bioavailable in two cases. A significant contribution to the recommended daily intake of metal trace elements by using rock salt for nutrition can be excluded.     

Correlation between total and EDTA/DTPA-extractable trace elements in soil and wheat

Wheat and wheat products are more important sources of energy and nutrients in diets of people in many cultures compared to other foods. The daily consumption of wheat is about 200 g/d/person in Western Europe and North America. On the other hand, 400–450 g of wheat and wheat products are consumed daily by average Turkish people. Wheat samples collected from the Iskenderun region in 1995 and 1996 and Ankara and Istanbul regions in 1995 were analyzed for their trace element content by instrumental neutron activation analysis (INAA). In addition, 13 soil samples were collected from the Iskenderun region in 1996. Total soil samples were analyzed by INAA and atomic absorption spectrometry (AAS), EDTA-extractable elements by INAA, and DTPA-extractable elements by AAS. Correlation analysis and enrichment factor calculations were applied to the trace element results. In wheat samples, a strong correlation was found between the elements such as Sc, La, Sm, Rb, and K whose main source is soil. The concentration of Se appeared to show larger variations among different regions. No significant correlation was observed for elements such as As and Se whose main sources in the atmosphere are anthropogenic activities.     

Multivariate statistical analysis of nutrients and trace elements in plants and soil from northwestern Russia

Results are summarized of several field and greenhouse experiments designed to estimate differences in the ability of some plant species to take up from soil essential nutrients and various trace elements and transfer them from roots to upper plant parts. Instrumental neutron activation analysis was used to determine concentrations of 22 elements in plant and soil samples. Correlation and principal component analysis were applied for interpreting a large volume of experimental results. In many cases there was no statistically significant positive correlation between element concentrations in soil and concentrations of these elements in plants. Moreover, relationships between elements were often different in soil and in different plant parts, thereby suggesting quite different element behaviours in soil and in plants. Our experimental results and data published in the literature revealed that macro- and trace element concentrations might serve as a specific indicator of plant taxonomy, thus allowing for differentiation of the plants in accordance with concentrations of certain elements in roots or in leaves. Short-term variations in concentrations of elements typical for different plant species and factors affecting these variations indicated that diurnal dynamics of plant element concentrations were regular and species-specific.     

Mineral content of Chinese medicinal herbs used as diuretic treatments for Taiwanese children

Eighteen major, minor and trace elements in 12 Chinese medicinal herbs commonly consumed by Taiwanese Children as diuretics were determined by instrumental neutron activation analysis (INAA). Dried and powdered herb samples were irradiated in a neutron flux of ca. 2 x 10(12) n/cm2 s under separate short and long irradiation schemes. Lichen (IAEA-336) was used as the reference standard, and tomato leaves (NIST-SRM 1570a) were employed for cross-checking the accuracy of the results. INAA was shown to be a reliable multi-element analytical method for determining the content of both toxicologically and nutritionally important minerals in Chinese medicinal herbs. Determined elements were present in the dried herbs in concentrations ranging from 10(4) to 10(-3) microg/g. The mineral contents and the maximum daily intake values of the tested herbs were compared with published values and with the recommended daily intakes for Taiwanese children as specified by the World Health Organization.     

A search for trace elements in some human intracranial tumors by instrumental neutron activation analysis

A investigation was undertaken to measure the presence of trace elements in some intracranial tumors using the instrumental neutron activation analysis technique. The following 20 minor and trace elements were investigated: Na, Mg, Al, P, Cl, K, Ca, Cr, Mn, Fe, Co, Cu, Zn, As, Se, Br, Rb, Sb, I, and Cs. Our results are compared with other trace element analyses in human brain tissue.     

Comparison of SR-excited X-ray fluorescence analysis with neutron activation analysis for hair and fiber

Human scalp hair and some kinds of vegetable and animal fibers were analyzed by means of the SR excited X-ray fluorescence method (SRXFA) and the neutron activation method (NAA). Human hair samples collected from five males and five females were washed by the IAEA method prior to analysis. In the SRXFA analysis, samples were excited by monochromated X-rays. Fluorescence X-rays were measured by an Si(Li) detector. The elements detected in all hair samples were S, Ca, Cu, Fe, Zn, Br, and Sr. The elements K, Ti, Cr, Mn, Ni, Se, Hg, and Pb were also detected in several samples. After SRXFA analysis these same samples were analyzed by the NAA method. Elements such as Cu, Zn, and Br were detected by both methods, and their relative concentrations show a good agreement of variation between individuals. However, Pb was only detected by SRXFA, and Na, Au, and Sb were only detected by NAA. Therefore, these two methods are complementary to each other for trace element analysis.     

Iron and Other Metals in Neuromelanin, Substantia Nigra, and Putamen of Human Brain

Abstract: Radiochemical neutron activation analysis has been used to determine the concentration of 36 elements in neuromelanin, 22 elements in substantia nigra, and 32 elements in putamen of healthy subjects without signs of neurological disorders. Substantia nigra and putamen tissues were carefully dissected from the brain using special surgical instruments and tools as well as an adequate sampling procedure to avoid the risk of metal contamination during sampling. Neuromelanin was isolated from putamen by a multiple-step procedure (extraction with phosphate buffer, lipid and protein elimination by methanol extraction, and sodium dodecyl sulfate-proteinase). The isolated pigment as well as substantia nigra and putamen underwent neutron activation analysis involving irradiation in a high-neutron-flux reactor, radiochemical separations, and counting of the induced radionuclides by computer-based γ-ray spectrometry. Iron was the element present in the highest concentration in all analyzed samples. The amount of iron was similar in substantia nigra and putamen (3,000 and 3,830 ng/mg wet weight, respectively) and 10 times higher in neuromelanin (30,800 ng/mg dry weight). Zinc was also present at high levels in three samples, ranging from 16.8 (substantia nigra) to 1,500 ng/mg (neuromelanin). Elements such as Zn, Cr, Se, Sr, Co, Sb, Ni, Hg, Ce, Au, Ag, Ta, and Sc were present in neuromelanin at much higher concentrations than in substantia nigra and putamen. These findings indicate that substantia nigra and putamen contain metals at higher concentrations than observed in blood and that neuromelanin has a particular affinity for metals.     

RNAA as compared to ICP-MS for the analysis of normal human serum

The merits of radiochemical neutron activation analysis (RNAA) and inductively coupled plasma mass spectrometry (ICP-MS) are critically discussed for the determination of trace and ultratrace elements in normal human serum. For RNAA, two semiautomated procedures, allowing the determination of up to 18 elements, are briefly described. ICP-MS has a series of interesting features for the determination of trace elements. Matrix and spectral interferences can mostly be avoided or corrected for. After a simple 5- or 10-fold dilution and addition of an internal standard, more than 20 elements can be measured precisely and accurately.     

Trace element determination in scalp hair of people working at a copper smelter

Instrumental neutron activation analysis was performed to assess the exposure degree of a worker group from a copper smelter. The results were compared with data of inhabitants of Kinshasa and Bandaka in Zaire. Excessive concentrations of Mg, Ca, V, Co, Cu, As, and Cd were observed in the investigated group. The distribution patterns of trace elements are shown. The plots of Cu concentration relations to selected elements, i. e., As, Co, and Zn, showed a plateau at about 300 ppm of Cu.     

The Level of Selenium and Some Other Trace Elements in Different Libyan Arable Soils Using Instrumental Neutron Activation Analysis

Elemental analysis of soils from two different arable regions in Libya was carried out to measure the level of many trace elements. Instrumental neutron activation analysis was used for the determination of 10 elements, viz., (Ba, Ce, Co, Cr, Cs, Fe, Sc, Se, Th, and Zn), using their long-lived radionuclides. The accuracy of the measurements has been evaluated by analyzing two IAEA soil reference materials: IAEA Soil-7 and IAEA leak sediment SL-1; precision has been estimated by triplicate analysis of the sample and that of the reference material. Irradiations were carried out at the Tajura Research Center reactor, at 5-MW power level. It is clear that in the Libyan soil selenium concentration is somewhat lower than in other countries. The results show that trace metal concentrations in Libyan clay surface soil are higher than the sandy soil.