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Abstract  

Sixteen minor and trace element contents of diet samples from three different social population groups in Taiwan were determined. Samples were prepared using duplicate portion technique by collecting the 15 subjects ate and drank during a 3-day period. Samples were homogenized, freeze-dried, and elemental concentration of minor and trace elements were determined by instrumental neutron activation analysis. Elemental concentrations and daily dietary intake of the elements were compared with those in the other nations, and possible origins were discussed.

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Abstract  

The Environmental Protection Agency has estimated that 20,000 lung cancer deaths per year may be related to radon exposure. This paper briefly describes the approach used to derive the Agency's central estimate of risk to the population. The weight-of-evidence for classifying radon as a known human carcinogen and the uncertainties associated with estimating risks from radon exposure provide an important context for these estimates and are briefly discussed.

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Abstract  

The minor and trace element content of diet samples from two different social population groups were determined. Samples were prepared by duplicate portion technique by colecting everything 16 subjects ate and drank during a 3-day period. Samples were homogenized, freeze-dried and elemental concentrations of Br, Co, Cr, Cs, Fe, K, Na, Rb, Sc, Se and Zn were determined by instrumental neutron activation analysis. Elemental concentrations and daily dietary intake of the elements were compared with the diets of other nations.

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Abstract  

Gamma-ray spectrometric measurements of nearground atmospheric aerosols by means of a lead shielded 80 cm3 Ge(Li)-coaxial detector are reported. The dust samples were taken from air-conditioning filters. Data on activity concentration of various natural and man-made airborne radionuclides are given and discussed for the time period from Octobr 1980 to November 1982. These data are useful in estimating the population's radiation burden due to gamma-ray emitting radionuclides.

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Summary  

Neutron activation analysis, using Au as flux monitor, was applied to determine the concentrations of Br, Cl, K and Na in blood of healthy male and female blood donors, selected from blood banks and hematological laboratories from different regions of Brazil. The aims of this study were to collect more reference values of the Brazilian population as well as to perform hematological investigations. The advantages as well as the limitations of using this nuclear procedure are discussed.

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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.

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Abstract  

The content of heavy metals in human hair may serve as an indicator of occupational or environmental exposure to metal compounds. However, before such exposure can be determined, the level of the element in a "normal" population must be established. The concentration of uranium in human hair was measured by flow injection — inductively coupled plasma mass spectrometry (FIAS-ICPMS) after acid digestion of the hair samples. All hair samples were rinsed in order to remove external contamination prior to the digestion in a 2:1 solution of concentrated nitric acid and 30% hydrogen peroxide. The limit of detection of the method, for a 50 mg hair sample, was 0.015µg/g, mainly due to the presence of impurities in the hydrogen peroxide. The range of uranium concentration in the initial test group was found to be 0.01–0.18 µg/g. The mean and median values of the entire study population were 0.062 and 0.050 µg U/g hair, respectively. Differences between the following sub-populations: male and female, smokers and non-smokers and people below and above 45 years of age were examined. The only statistically significant difference was found in the latter group (p = 0.03).

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Abstract  

Atmospheric contamination pattern by Pu-radionuclides over a 30 km zone of the Chernobyl nuclear power plant in 1987–1988 has been examined. Aerosol samples were analyzed for isotopic composition by using gamma- and alpha-spectrometric, and radiochemcal methods. Preliminary analysis of isotopic and fractional composition of aerosols carried out earlier indicated that over the first few months after the Chernobyl accident the relative contribution of238,239,240Pu to air contamination was lowered as compared with beta-active products. At present, however, alpha-active plutonium isotopes became the dominant radioactive contaminants of the atmosphere and the concentrations of238,239,240Pu inhaled fractions turned out to be lower than the limiting permissible values based on the USSR radiation safety standards for radioactive contamination of the atmosphere for the limited part of population exposed to radionuclides. Neverheless, it is necessary to know even moderate levels of atmospheric contamination by Pu-radionuclides, since their long impacts on the personnel operating in the 30 km zone of the Chernobyl NPP and population residing in the adjavent regions have not been studied properly. So, the risks for population health of such impacts cannot be generally excluded from consideration.

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A method for optimization of a TLC separation based on use of a genetic algorithm is described. The procedure was tested by optimization of the reversed-phase HPTLC separation of a mixture of six pesticides and satisfactory optimum results were obtained. The performance of the genetic algorithm was tested by measurement of the number of generations, the population size, the mutation probability, and the crossover probability. Three separation criteria ( MRF , R * and R **) were examined as fitness functions. The genetic algorithm was compared with the simplex method.

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Abstract  

New experimental data has been obtained on heavy metal and rare-earth element concentrations in environmental objects, namely pine needles and soils, caused by atmospheric pollution in different regions of the Kola Peninsula. The investigation was performed with the use of epithermal neutron activation analysis at the IBR-2 fast pulsed reactor. Analysis of nearly 40 element distribution in pine-needles and solids from the studied geographical points testifies of a strong contamination source —the nickel smelting complex in Monchegorsk. The contamination levels for Ni, Co, Cr, Se, and others are also high and may be hazardous to the population of this region because some of these elements are carcinogenic.

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