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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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Abstract  

Arsenic and cadmium contents in eight edible mushroom species (Agaricus bisporus, Agaricus sp, Pleurotus ostreatus, Pleorotus florida, Pleorotus eryngui, Pleurotus osteatus, Pleurotus salmoneostramineus, Lentinula edodes) consumed by Brazilian population were determined by instrumental neutron activation analysis (INAA) and graphite furnace atomic absorption spectrometry (GF AAS), respectively. Arsenic concentrations varied from 0.009 mg/kg in P. eryngui to 0.210 mg/kg dry weight in L. edodoes and Cd from 0.011 g/kg in P. eryngui to 0.229 mg/kg dw in P. salmoneostramineus. The consumption of mushrooms in São Paulo-Brazil may be considered safe from a toxicological point of view as As and Cd presented levels of ingestion are below the maximum levels recommended by the World Health Organization.

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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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Quantitative evaluation of phytochemical diversity in Adhatoda vasica Nees populations from five different ecogeographical regions was performed using a highly sensitive, robust and economic high performance thin layer chromatography (HPTLC) procedure. The method was validated for specificity, precision and accuracy as per the guidelines affirmed by International Conference on Harmonization of technical requirements for registration of pharmaceuticals for human use (ICH). The findings support the existence of distinct natural chemotypes within the species. Two out of the five regions had about three times higher mean vasicine content than the remaining three regions. The comparative phytochemical fingerprint profiles were quite similar except for the concentration variation seen for different alkaloids. As the quinazoline alkaloids are the biologically active compounds in A. vasica, the samples that accumulate high levels of alkaloids seem to be promising for further propagation.

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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  

The aim of this study is to investigate the contents of toxic and essential trace element such as As, Hg, Se and Zn by neutron activation analysis in coastal fishes consumed by the general population of Malaysia. The mean values of the elements analysed expressed in mg/kg fresh weight ranged 1.42–5.61, 0.06–0.42, 4.2–20.6, 0.41–1.28 for As, Hg, Zn and Se, respectively. The maximum permissible limit for As in food was set at 1.0 mg/kg under the Malaysian Food Regulations. Our results showed that consumption of coastal fishes is not permitted under the regulations, while the levels of Hg, Se and Zn were within the permissible limits. The daily dietary intake of As and Hg at 400 g and 30g respectively are still within the tolerance levels.

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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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Journal of Radioanalytical and Nuclear Chemistry
Authors: B. Karakelle, N. Öztürk, A. Köse, A. Varinlioğbrevelu, A. Erkol, and F. Yilmaz

Abstract  

The city of Kocaeli is in the western part of Anatolia in Turkey and has a population of approximately 1.000.000. There is no information about radioactivity in the Kocaeli soils samples so far. For this reason, the concentrations of the natural radionuclides in soil samples from 27 different sampling stations in Kocaeli Basin and its surroundings have been determined. The results have been compared with other radioactivity measurements in different country"s soils. The typical concentrations of 137Cs, 238U, 40K, 226Ra, 232Th found in surface soil samples ranged from 2±0.6 to 25±6 Bq/kg, from 11±4 to 49±10 Bq/kg, from 161±30 to 964±127 Bq/kg, from 10±4 to 58±11 Bq/kg, and from 11±3 to 65±13 Bq/kg, respectively.

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