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Abstract  

The content of the following trace elements, Ag, Co, Cr, Cs, Fe, Hg, Rb, Sb, Se and Zn has been evaluated in the diets, excretion (urines and feces), blood and hair samples taken from different groups of subjects. Each population group is composed by five or more individuals selected in order to be representative of the adult population living in a well defined community. Some communities, with different socio-economical living habits, and displaced in different regions of Italy, have been considered in order to detect the variability, if any, of the trace element distribution among the Italian population. The data obtained seem to show a reasonable uniformity of the average trace element daily intakes in different regions of Italy. Beside the individual variability, very significant differences among the groups studied have not been found, as the trace element contents in excreta, blood and hair samples are concerned. All data are compared with similar data referred to population living in other countries.

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Abstract  

The trace element composition of whole blood has been investigated in adult population in Bangladesh. The population was formed of one hundred individuals randomly selected from a working community of five hundred adults. The blood samples were freeze dried and analyzed using the external beam PIXE method. In this analysis, proton beams of 2 MeV energy and about 30 nA current were used for characteristic X-ray excitation. The concentration of eight elements, K, Ca, Fe, Cu, Zn, Br, Rb and Pb were determined by comparison with a calibration obtained from NBS orchard leaves. The frequency distributions of all the elements measured are presented and the results are compared with available data.

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Abstract  

The daily intake of uranium (238U) by an urban Indian adult population was estimated by the analysis of a duplicate diet, drinking water, and air samples using neutron activation and radio-chemical separation. The uranium intake through food is 0.55 g which is much larger than that from drinking water and air, at 0.09 and 0.01 g, respectively. The total daily dietary intake of uranium, calculated from the concentrations measured in the individual food ingredients and their daily consumption (based on the national survey), is found to be 2.2 g which is a factor of 3.5 higher than that based on a duplicate urban diet. The maximum contribution to the daily intake is found to be from cereals. The lower intake by the urban population is most likely due to their lower food consumption.

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Abstract  

Due to its essential characteristics, the daily dietary selenium intake of individuals should be monitored accurately. In the current work, daily selenium intake of different Brazilian population groups based on duplicate portion diet analysis was evaluated and compared with the new estimated average requirement values (EAR), to assess if selenium deficiency or excess could be observed in these groups. Selenium content was determined by neutron activation analysis (NAA). The average daily dietary selenium intake found was 26.3 (±8.3) ·g/day for children from the city of São Paulo, 37.4 (±16.0) ·g/day for children from Belém, 107 (±107) ·g/day for children from Macapá, 28.4 (±7.5) ·g/day for institutionalized elderly, 32 (±6) ·g/day for non-institutionalized elderly and 37 (±17) ·g/day for university students from São Paulo. Most daily dietary selenium intake range observed were below the EAR values. The values obtained for children groups from Belém and Macapá cities, whose intake levels were much higher than the recommendation, were an exception.

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Abstract  

The results on the concentrations of thorium, uranium, and plutonium in human tissues of world-wide general populations are summarized. The majority of thorium and uranium are accumulated in the skeleton, whereas, plutonium is divided between two major organs; the liver and skeleton. However, there is a wide variation in the fractions of plutonium in the liver and the skeleton of the different populations.

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Abstract  

The content of the trace elements As, Br, Co, Cr, Fe, Hg, Sb and Zn has been evaluated in hair samples from selected population groups within Malaysia. Each population group was formed of individuals selected to be representative of the adult population living in a well-defined community. The groups were chosen from distinct regions with different socio-economical living habits in order to detect variability of the trace element burden among Malaysian. All the measurements were performed by means of instrumental neutron activation analysis after the hair samples were carefully washed according to standard procedures. The results for all elements investigated do not differ significantly from reported values for other regions of the world. The levels of As, Hg, and Sb are significantly different for the various groups and is strongly linked to local environmental factors.

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Abstract  

In the present paper, for the first time the multielemental compositionof hair samples of Indian populations living in the Xingu Park Reservation,in the Brazilian Amazonic region has been determined, by INAA. Irradiationswere carried out at the Interfaculty Reactor Institute (Delft, The Netherlands)and, using a combination of different irradiation and decay times, about 40elements could be determined in the hair. Previous analysis made at the RadiochemistryDivision of IPEN/CNEN-SP (Brazilian Nuclear Energy Commission) of hair samplesof a Brazilian control population allowed the determination of 20 elements,also by INAA. Comparison of the data obtained for the Indian populations andthe controls showed very significant differences in elemental compositionsfor some elements, like Hg, Mn and Al while for others, like Cu and Zn, theconcentrations were similar. A discussion of the differences found for otherelements also is made in the present paper.

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Abstract  

Instrumental neutron activation analysis has been selected for use to measure the level of 11 environmentally significant trace elements in human scalp hair of Indonesian, Canadian and Canadian-of-Indonesian-origin (INCN) population groups. Concentration ranges and geometric means are presented. Concentration ratios of each group are evaluated to find a possible relationship between the elemental concentrations of scalp hair and the environmental condition in which the donors live.

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Abstract  

Concentrations of As, Cd, Hg, Pb, Sb and Zn have been measured in hair from population groups with varied types of environmental exposure. Rural and urban controls have exhibited low levels of most toxic elements, whereas people residing near urban lead refineries, rural gold refinery and other industries have shown high elemental concentrations in their hair. A combination of instrumental as well as radiochemical neutron and photon activation analysis methods have been used to determine the concentrations of the above elements. The precision and accuracy of these methods have been evaluated.

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Abstract  

In the present work, determination of mercury in the head hair of populational groups living near a heavily industrialized region in São Paulo and of Indians living in the Xingu park in the Amazonic region, was carried out by instrumental neutron activation analysis. A control group of people with no suspicion of contamination by mercury was also studied. The range of mercury concentrations found up to now were: for the control group from 0.26 to 02.5 ppm; for the Indians from 6.9 to 34 ppm, and for the industrialized region inhabitants: from 0.30 to 3.0 ppm.

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