Measurement of body composition by in-vivo neutron-activation analysis.
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Activation Analysis↗
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Neutron activation analysis of trace elements in biological tissue.
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Activation Analysis↗
Identification of single-stranded copper wires by nondestructive neutron activation analysis.
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Activation Analysis↗
[Usefulness of neutron activation analysis in forensic medicine].
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Activation Analysis↗
Determination of airborne cadmium in environmental tobacco smoke by instrumental neutron activation analysis with a compton suppression system.
Concentrations of cadmium, a toxic trace element, were measured in the indoor air of several public places where environmental tobacco smoke was present. Particulate-phase cadmium concentrations were determined by analyzing air filter samples using epithermal instrumental neutron activation analysis in conjunction with a Compton suppression gamma-ray detection system, in which the detection limit for cadmium was reduced to a few nanograms per filter. A cascade impactor and a personal filter sampler were used to collect the indoor suspended particulate matter for size-fractionated mass as well as total mass, respectively. Results show that where environmental tobacco smoke is present, cadmium concentrations are significantly higher than background and that about 80% of the cadmium found in indoor airborne particulate matter is associated with particles with aerodynamic diameters less than 1.8 microns. In one instance, airborne cadmium concentrations in a music club were found to be 38 ng/m, which is at least 30 times higher than background.
Air Pollutants↗
Concentration of rare earth elements, As, and Th in human brain and brain tumors, determined by neutron activation analysis.
Toxic elements As and Th, six rare-earth elemental profiles of brain tumor tissues from 16 patients of astrocytomas (grade I-III), and normal human brain tissues of 18 male, age-matched autopsies serving as controls have been studied by radiochemical neutron activation analysis. P-204 [di(2-ethylhexyl) phosphate] extraction chromatography column was used for group separation of rare-earth element (REE) by one step. Compared with the normal brain tissues, the analytical results showed that the concentrations of Th, La, Ce, Gd, and Lu were significantly higher in tumor tissues (P < 0.01 or 0.001). The possible effects of REE on tumor cell were discussed.
Adult↗
[Biodistribution studies on selenium and mercury in mice using instrumental neutron activation analysis].
An attempt was made to compare the Se and Hg abundance's in liver, kidneys and blood after simultaneous intraperitoneal injections of inorganic mercury (as HgCl2) and SeO2 or organic Se-compound (i.e. seleno-cystine, seleno-methionine or selenodiglutathione). Instrumental neutron activation analysis was applied as the analytical method due to the advantages of both its sensitivity and chemically non-destructive procedure. No neurological or other lesion symptoms of Hg and Se intoxication were found. Especially high concentrations of Hg and Se in liver and blood were found after simultaneous i.p. injections of HgCl2 and Se-compounds. Moreover, significantly high abundance's of Se and Hg in liver and blood were found after simultaneous injections of seleno-methionine and HgCl2. On the other hand, only for kidneys the Hg content after the single injections of HgCl2 was considerably higher in comparison with the simultaneous injections of Hg and Se. We suggest that Se-compounds protects against renal lesions by decreasing the concentration of Hg in kidneys. Hg2+ ions are bounded by selenohydryl groups of the metabolites of injected Se-compounds. Moreover, the binding yield of Hg2+ ions with the metabolites of Se-compounds depends upon the chemical form of injected Se-compounds.
Animals↗
Determination of aluminium by instrumental neutron activation analysis in biological samples with special reference to NBS SRM 1577 bovine liver.
It was found that a well thermalized heavy water-moderated research reactor can be used to determine the Al content of biological samples without separation of P, Na and Cl. The contribution of the 31P(n,alpha)28Al reaction was corrected from the known concentration of P and the measured effective value. It was found that the contribution is only about 10%. A method is suggested for the determination of Al using instrumental neutron activation analysis.
Aluminum↗
Instrumental neutron activation analysis of Standard Reference Material 1941, Organics in Marine Sediment. Element content and homogeneity.
The National Institute of Standards and Technology has developed a new Standard Reference Material 1941, "Organics in Marine Sediment." In addition to the organic constituents, over 30 elements have been determined by instrumental neutron activation analysis and prompt-gamma activation analysis. The homogeneity of the material was investigated and relative standard deviations of single-element concentrations in 250-mg samples were found to be 1% or less with regard to major inorganic constituents and rare earth elements. A slightly higher relative SD was found for elements that may stem from biological or anthropogenic input. The element concentrations determined in this work are discussed in comparison to concentrations in other similar reference materials. Concentrations for 31 elements will be included for information on the certificate.
Environmental Monitoring↗
[Measurement of contents in organs of selenium- or vitamin E-deficient rat using instrumental neutron activation analysis].
The contents of iron (Fe), cobalt (Co), zinc (Zn), and selenium (Se) in the organs (liver, kidney, spleen, heart, lung, and brain) and the liver cell fractions (nuclear, mitochondrial, microsomal, and cytosolic fractions) of Se- or vitamin E (VE)-deficient rats were measured using instrumental neutron activation analysis (INAA). The contents of Fe in the liver of Se-deficient rats, and in the liver and the spleen of VE-deficient rats were increased compared with those in normal rats. Fe contents increased mainly in the microsomal fraction. Contents of Co in the organs and liver cell fractions of Se- and VE-deficient rats were markedly low, reflecting the Co contents in both diets. Contents of Zn in the organs and liver cell fractions of Se- and VE-deficient rats decreased to 60-80% of the contents in normal rats. The Se contents in Se-deficient rat organs except for the kidney, spleen, and brain were below the detectable level under the present conditions. Se contents in VE-deficient rat decreased to 50-80% of those in normal rats in all organs and fractions. It is suggested that oxidative stress due to Se- or VE-deficiency affects the dynamics of Fe and Zn.
Animals↗
Uranium content of blood, urine and hair of exposed and non-exposed persons determined by radiochemical neutron activation analysis, with emphasis on quality control.
Recent reviews have highlighted the diversity (and sparsity) of data for uranium concentrations in body fluids, bone and soft tissues, and it is unclear to what extent this reflects genuine geographical or biological variations. In the present work, a very sensitive radiochemical neutron activation analysis technique (detection limit, 1-2pg g-1) was applied to an exploratory study of uranium levels in hair, urine and blood of non-exposed and occupationally exposed persons. Since quality control in much previous work has been somewhat neglected, this aspect was emphasized by the use of a wide range of suitable reference materials, by standard addition experiments, and by care in sampling and sample handling. For controls, typical levels found in hair, urine and blood were 10 ng g-1, 10 and 5 ng l-1, respectively. The urine values correspond to the lower end of the literature data, while for blood our value is about two orders of magnitude lower than the presently quoted level. In the case of occupationally exposed persons, it was found that hair shows some promise as an indicator of exposure.
Hair↗
Instrumental neutron activation analysis of essential and toxic elements in child and adolescent diets in the Chernobyl disaster territories of the Kaluga Region.
The main etiologic factor of various diseases, syndromes and pathologic conditions is an excess, deficiency or imbalance of trace element intake into the human body. Children seem to be the most sensitive to each change of trace element homeostasis. An inadequate essential trace element intake may result in an undesirable consequence that can apparently multiply against a background of additional unfavourable environmental influence such as high levels of radiation, organic and inorganic toxins, etc. Thus, the quality control of children's diets assumes urgent importance within the regions covered by the Chernobyl disaster. Instrumental neutron activation analysis was used to estimate contents of Ag, Br, Ca, Cl, Co, Cr, Cs, Fe, Hg, K, Mg, Mn, Na, Rb, Sb, Sc, Se, Sr, and Zn in the diets of children and adolescents. Diets were chosen from day care centre, boarding school and technical college cafeterias situated within the south and south west territories of the Kaluga Region, where radionuclide contamination ranges up to 15 Ci/km2. Ca and Zn deficiencies were found in the diets of children and adolescents aged 7-18. The Ca intake is only 212 mg/day, 5 times lower than that in developed countries. The Zn intake is 6.8 mg/day, 2 times lower than the level recommended by the WHO.
Adolescent↗
The affect of industrial activities on zinc in alluvial Egyptian soil determined using neutron activation analysis.
Thirty-two surface (0-20 cm) soil samples were collected from different locations in Egypt representing non-polluted, moderately and highly polluted soils. The aim of this study was to evaluate total Zn content in alluvial soils of Nile Delta in Egypt by using the delayed neutron activation analysis technique (DNAA), in the irradiation facilities of the first Egyptian research reactor (ET-RR-1). The gamma-ray spectra were recorded with a hyper pure germanium detection system. The well resolved gamma-ray peak at 1116.0 keV was efficiently used for 65Zn content determination. Zn content in non-polluted soil samples ranged between 74.1 and 103.8 ppm with an average of 98.5 +/- 5.1 ppm. Zn content in moderately polluted soils ranged between 136.0 and 232.5 ppm with an average of 180.1 +/- 32.6 ppm. The highest Zn levels ranging from 240.0 and 733.0 ppm with an average of 410.3 +/- 54.4 ppm, were observed in soil samples collected from, either highly polluted agricultural soils exposed to prolonged irrigation with industrial wastewater or surface soil samples from industrial sites.
Egypt↗
Mercury content of common foods determined by neutron activation analysis.
The mercury contents in samples of flour, sugar, nonfat dry milk, potatoes, hamburger, chicken breast, shrimp, liver, eggs, and whole milk were determined by neutron activation analysis. The mercury was separated by anion exchange chromatography and precipitated as the sulfide. The mercury concentrations for all these foods were below 50 parts per billion.
Activation Analysis↗
Nutrient elements of commercial tea from Nigeria by an instrumental neutron activation analysis technique.
A prototype miniature neutron source reactor (MNSR) with a thermal neutron flux of 3.0 x 10(11) n cm(-2) s(-1) has been used to determine the concentrations of some nutrient elements leading to short-lived activation products in commercial tea leaf samples from Nigeria. A total of eight elements Al, Ca, Cl, Cu, K, Mg, Mn and Na, that can be routinely used for quality control purposes, were analyzed in this study. Two biological reference materials, tomato leaves (NIST-1573) and citrus leaves (NIST-1572) were used as the standard and quality control materials, respectively. The analytical results show that the average concentrations of Al, Ca, Cl, Cu, K, Mg, Mn and Na in Nigerian tea are slightly higher when compared with a Chinese herbal tea analyzed in this study. The concentration ratios of K/Ca were found to be high in all the samples analyzed suggesting cultivation in potash-rich soils.
Quality Control↗
The feasibility of measuring manganese concentrations in human liver using neutron activation analysis.
Manganese is an element which is required by the human body. However, as with most metals, in large amounts manganese can be toxic. People who suffer from severe manganese intoxication have symptoms similar to those of Parkinson's disease. Preclinical symptoms of manganese intoxication have recently been detected in individuals working in industries which have manganese dioxide dust in the air. The concentration of many toxic elements can be measured in vivo using neutron activation. A small dose of neutrons is delivered to the organ of interest, the neutrons are readily captured by the target nuclei, and the gamma rays given off can be detected outside of the body. A neutron activation analysis system is being developed to measure manganese concentrations in humans. The McMaster KN-accelerator supplies the neutron beam and the thermal neutron capture reaction 55Mn(n,gamma)56Mn is used. The half-life of 56Mn is 2.58 hr and thus counting can occur after irradiation. The 847 keV gamma ray given off when 56Mn decays is detected using a Nal detector. Calibration curves are made using phantoms with known concentrations of Mn. This system will be used to monitor manganese levels in individuals who have occupational exposure to the element. Preliminary measurements, using liver phantoms, give a minimum detectable limit for Mn in the liver of less than one part per million, which is well below normal levels.
Animals↗
Content of trace elements in the respirable fractions of the air particulate of urban and rural areas monitored by neutron activation analysis.
The concentrations (ng/m3) of more than 30 trace elements have been determined in the total air particulate matter and in the size-segregated fractions collected in urban, industrialized, and rural residential areas in northern Italy by means of a multistage inertial impactor with the PM10 inlet. All measurements have been carried out by instrumental neutron activation analysis, except for Pb and Cd, which have been determined by electrothermal atomic absorption spectroscopy. Analytical quality assurance procedures have been developed with special regard to blanks, reagents, and sampling. Total concentrations and the granulometric distribution found in the different locations are reported and compared.
Air Pollutants↗
Thin film thickness determination with neutron activation analysis.
Thickness determination of Ta2O5 thin films, deposited on the glass substrates and metallic indium and gold thin films on both glass and aluminum substrates, were performed by neutron activation analysis. Thickness determination of these thin films were made by comparing gamma-rays emitted from the radio-isotopes in the thin film with the substrate material followed by the neutron irradiations. The method led to determination of the film thicknesses without using any standard sample. A complementary optical transmission measurement was also applied on multi-layered Ta2O5 thin films for determining the individual layer densities.
Journal Article↗