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Journal of Radioanalytical and Nuclear Chemistry
Authors: Chang Lee, Mun Kang, Wanno Lee, Geun Choi, Young Cho, Hee Kim, and Kun Chung

Abstract  

210Po in the daily diet in Korea was analyzed and the ingestion dose from an intake of 210Po was estimated by considering the dietary habit of a Korean person. The 210Po concentrations of a leafy vegetable (0.36 Bq·kg−1 for lettuce) in the terrestrial food were higher than those of grain, whereas Chinese cabbage had a lesser 210Po concentration (0.019 Bq·kg−1). The 210Po concentration of the animal product was similar to those detected in the grain and vegetable. The 210Po concentrations in the shell and crustaceous were high from 19.1 to 33.0 Bq·kg−1, however, its value fell in the overall range of the reported values. The effective dose from 210Po for an adult from the Korean population was about 269.4 μSv·y−1. Nearly 80% of the ingestion dose from the intake of 210Po was attributed to the consumption of seafood. It suggests that the marine food ingestion is a critical pathway for natural 210Po to the Korean population.

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Journal of Thermal Analysis and Calorimetry
Authors: Lisardo Núñez-Regueira, J. Rodríguez-Añón, J. Proupín-Castiñeiras, Maria Villanueva-López, and O. Núñez-Fernández

Abstract  

Microcalorimetry was used to study the seasonal evolution over one year of the microbial activity in a humic-eutrophic Cambisol soil as a function of its forest cover. The study was carried out on three soils with identical origin but covered with different forest species: pine, eucalyptus, and a typical Atlantic-humid riverside forest. Some other physical, chemical and biological properties and environmental parameters, mainly humidity and environmental temperature, were considered to analyze their influence on soil microbial activity. The study was performed using a microcalorimeter Thermal Analysis Monitor 2277 in which the experiments were carried out with 1 g soil samples treated with 1.25 mg glucose g–1 soil. From the measured results it follows that pine forest soil is the least productive of the three, as it generates an average heat of 2.7 vs. 5.9 J g–1 generated by the eucalyptus forest soil and 3.1 J g–1 generated by the riverside forest soil. These results are dependent on the remaining physical, chemical and biological features analysed and because of this, pine forest soil, with a pH value 3.3 in spring, shows a small capacity to maintain a stable microbial population which is the lowest of the three (0.079108 to 0.46108 microorganisms g–1 soil) while riverside soil microbial population is in the range from 7.9108 to 17108 microorganisms g–1 soil.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: A. Arias, A. Arias, M. Oddone, M. Oddone, G. Bigazzi, G. Bigazzi, A. Di Muro, A. Di Muro, C. Principe, C. Principe, P. Norelli, and P. Norelli

Summary  

Newly produced fission track (FT), instrumental neutron activation analysis (INAA) and micro-Raman spectrometry data have been used to characterize the classical source areas of the Milos obsidians better and to check the provenance of obsidian artefacts. The Bombarda-Adhamas and Demenegaki obsidians yielded indistinguishable FT ages 1.57±0.12 and 1.60±0.06 My, respectively, in agreement with previous FT data. By INAA analyses it was possible to discriminate between the three obsidian sources on Milos: Bombarda-Adhamas, Demenegaki and A. Ioannes. Raman spectroscopy has been found to be a valuable technique to gain a chemico-structural characterization of a given obsidian population in terms of dissolved water content and microlite distribution/composition.

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Abstract  

Water samples collected from 321 sampling points at 1 km intervalsat a site located close to the industrial and geological areas in the Gedizriver were analysed for U, Ra, Na, Mg, Mn, K, Ni, Cd, Co, Pb, Al, Fe, Cr,Zn, Cu and Ca. Heavy metal concentrations in the samples were determined byatomic absorption spectroscopy, laser excited fluorescence, and radon collectorchamber. Factor analysis was used to describe the relationship among 16 elements.Four factors were extracted and they account for 67% of the total variancein the data. These factors are named as industry, sea, agriculture and geology.According to this result, not only industrial plants but also geological structureand agricultural activities were seen to contribute in polluting of the riverwater. Beside, these factors have shown that a lot of agricultural activitiesand a sharp increase in the population of the Gediz basin, and industrialdevelopment related to above reasons speed up pollution of water sources andbecome a potential risk on the unpolluted sources.

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Abstract  

The ultimate purpose of all studies on environmental contamination is to protect human life; as a consequence the knowledge of the trace element pathways from environment to man is of paramount importance because it allows the assessment of a clear relationship between any environmental contamination and its effects on man. To this extent two different kinds of environmental studies will be described in this paper: (a) Studies of the geographic variations on the whole national territory of the natural levels of trace elements in water, food and some human tissues. (b) Studies of selected areas where a critical population group is exposed to abnormal levels of some trace elements. The main trace elements considered are: Co, Cr, Cs, Fe, Hg, Ni, Rb, Sb, Sc, Se and Zn; all the measurements were performed by means of non-destructive neutron activation analysis.

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Abstract  

Extensive use of pan, by one-tenth of world"s population, entails the evaluation of trace element contents in its ingredients. Radiochemical neutron activation analysis (RNAA) was developed and successfully employed to determine the concentration of 36 trace elements (essential, toxic and nonessential) in its four basic ingredients, leaf of betel pepper, betel nut, catechu and lime. The radiochemical separation methodology has significantly improved the detection limits of most of these elements due to suppression of Compton background. This study provides the base-line values of certain toxic and essential elements in these ingredients. The daily intake of essential and toxic elements through pan was estimated and compared with the recommended values. The cumulative intake of Mn is four times higher than the recommended value and that of toxic elements is well below the tolerance limits.

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Abstract  

Indoor natural radiation dose existing in dwellings of Coonoor have been estimated using thermoluminescent dosimeters. TLDs are displayed in indoors and are replaced after three-month period. The seasonal averages of the dose rate and the annual effective dose equivalent are calculated from the measured results. Geographical and seasonal variations as well as the differences between indoor to outdoor dose rates have also been studied. Very good correlation exists between the indoor dose rates measured by TLD and environmental radiation dosimeter with correlation coefficient of 0.91. The annual effective dose equivalent to the Coonoor population due to indoor gamma radiation was estimated to be 970 mSv/y for the period of 1997–1998.

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Abstract  

Uranium (238U) and thorium (232Th) concentrations were evaluated in different cereal, fruit and vegetable samples by using a method based on the calculation of the detection efficiencies of the emitted a-particles by CR-39 and LR-115 type II solid state nuclear track detectors (SSNTD) and measuring the resulting track densities. The influence of the soils on which the plants grow, and the fertilizers used was investigated. Total daily intakes of 238U and 232Th for a typical food basket were estimated to be 1.16 Bq.d-1 and 0.94 Bq.d-1, respectively, corresponding to a total committed effective dose of 0.27.10-7 Sv.d-1. Annual committed effective doses due to 238U and 232Th originated from the ingestion of different foodstuffs were evaluated for the adult members of the population by using the ICRP ingestion dose coefficients.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: I. O. Abugassa, S. O. Abugassa, Y. S. Khrbish, A. T. Bashir, K. Doubali, and N. Ben Faid

Summary  

The trace elements composition of gallbladder stones samples of the types cholesterol, pigment and mixed stones in addition to bile have been investigated by k 0-instrumental neutron activation analysis (k 0-INAA). The samples were obtained from several individuals of adult subjects of the Libyan population who undergone open surgery of gallbladder (cholecystectomy) at Al-khadra University Hospital in Tripoli. The samples were lyophilized, irradiated together with Au wire and Zr foil, which serve as flux ratio monitor and a parameter at TNRC. Concentrations of 24 elements in gallstone and 23 elements in bile were determined. The levels of the trace elements in the various samples investigated are measured and discussed. The reliability of the analysis was checked with several biological standard reference materials.

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Abstract  

The building materials and products whose content of natural radionuclides are contributors to the radiation exposure of the population. In this study several types of building materials used for construction of living buildings in Slovakia were examined. The concentrations of natural radionuclides (226Ra,232Th and40K) were determined by -ray spectrometry with an HPGe detector. In the second part of the work, sixty samples of building products (panel), used for dwelling construction in several towns in Slovakia, were analysed. The concentration of natural radionuclides and the radium equivalent activity content in the inner-and outerside of the wall were estimated. The results were used for the calculation of the annual mean effective photon dose rates, by the model and calculation procedure of KRISIUK and KARPOV.

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