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Abstract  

Thorium-232 and238U contents in four food groups were measured by inductively coupled plasma mass spectrometry (ICP-MS). Daily intakes of232Th and238U for Japanese were estimated to 2.22 mBq and 15.5 mBq per person, respectively. Furthermore, preliminary estimations were made for the effects of imported foods on internal exposures for Japanese.

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Abstract  

Excess dietary intake may increase the risk for the hyperthyroidism in the elderly. This study investigated iodine dietary intake by epithermal neutron activation analysis (ENAA) analyzing duplicate portion diet and fortified table salt samples. Duplicate diet samples were obtained from a group of twenty-five steel mill workers from the city of São Paulo, over a 3-day period. The samples were freeze dried, mixed and homogenized. Fortified table salt brands were collected from the market and were analyzed with no pre-treatment. Assays for the iodine concentration in the table salt samples revealed values between 24 to 65 mg/kg. The average iodine daily intake for the worker’s diets was 813 μg/day, ranging from 402 to 1363 μg/day. In some cases daily intakes were around 10 times higher than the recommended dietary allowance (RDA) value (150 μg/day).

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Abstract  

This article explains the application of a few nuclear and non nuclearanalytical techniques to determine a number of toxic and essential trace elementsin human daily intakes. The diets are the food patterns of different populationof Iranian provinces with different food habits.In this article a comparisonhas been made for mineral micronutrient intaken by the different populationvia the pattern of nutrients in their daily diets. In the meantime resultingoutcome from different analytical techniques including instrumental and radiochemicalneutron activation analysis have been compared and discussed.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
H. Dang
,
H. Desai
,
S. Kayasth
,
D. Jaiswal
,
C. Wadhwani
, and
S. Somasundaram

Abstract  

The daily intakes of trace elements by infants showing optimal pattern of growth are used as the basis to estimate the requirements of Fe, Co and Se during infancy. Since milk is the only food and source of nutrition in the first few months of life, the requirements of these elements are calculated from their average concentrations in human milk and the volume of milk required to supply sufficient amount of energy for maintenance and healthy growth of infants. The concentrations of the three elements in human milk were determined, using the technique of neutron activation followed by radiochemical separation.

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Abstract  

In the present work, the concentration of the 14 elements Br, Ca, Cl, Co, Cs, Fe, K, Mn, Na, Rb, Sc Se and Zn have been determined by INAA in diets of four different groups: (a) 19 pre-school children, (b) 18 healthy adults, (c) 23 elderly people living in private institutions and (d) 19 patients with chronic renal failure (CRF). The contents of proteins, lipids and carbohydrates were also analysed in the diets. The daily intakes of the elements analysed were compared to the recommended values set by RDA or WHO.

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Abstract  

An instrumental neutron activation analysis technique has been utilized to study the prevailing levels of certain inorganic trace elements in different varieties of rice produced in Pakistan. The data have been compared with those of other countries. The elemental ratios within rice and rice to husk have been computed to evaluate indirectly the impact of soil and environment on the rice crops. The dietary spectum for the inhabitants of Rawalpindi/Islamabad areas has been evaluated by estimating the daily intake and comparing with allowances suggested in the literature.

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Abstract  

The trace element contents of Taiwanese diet were determined using conventional neutron activation analysis. Sample were prepared with duplicate portion technique by collecting food items ate and drank during a 3 day period in winter. Samples were homogenized, freeze-dried, and elemental concentration of trace elements were determined by instrumental neutron activation analysis. The interference from fast neutron induced reactions were corrected. Concentrations and daily dietary intake of the elements were compared with those collected in the summer, resulting less daily intake of K, Ca, Mn, Fe, and Zn among Taiwanese than the values recommended by WHO and RDA. Alarming low intake of Fe for females and Zn among Taiwanese were indicated.

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Abstract  

Traditional medicinal seeds prescribed for specific treatment purposes, were purchased from local markets and analyzed by INAA. The samples were irradiated at Es-Salam research reactor, at a power of 5 MW for 6 h. The accuracy of the method was established by analyzing reference materials. Twenty elements were measured, with good accuracy and reproducibility. The concentration of elements determined, was found to vary depending on the seeds. The daily intake of essential and toxic elements was determined, and compared with the recommended values. The probable cumulative intake of toxic elements is well below the tolerance limits.

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Abstract  

It is important that in radioiodine dosimetry for low levels of daily intake, allowance must be made for the normal daily intake of stable iodine. This intake varies from one region to another, and variations are observed from one person to the next within a region, depending on eating habits. Measuring iodine in the urine over 24 hours can indirectly assess these variations. Analysis of the total iodine in the urine was carried out for 69 French people living in a temperate maritime region or in mainland France. This study justifies individual assessment of the coefficient of iodine transfer to the thyroid by means of this survey based on the urinary iodine analysis. The consequences for man of the release of 129I around a nuclear reprocessing plant were analyzed by applying the methodology published previously by the authors. A software program based on the iodine biokinetic model recommended by the ICRP was used to calculate the daily urine excretion of 129I for five different diets of total iodide in a ratio of 10-4 for 129I/127I. This model makes it possible to set a practical detection limit of 20 mBq (0.003 µg). This approach is important from a practical point of view for health physicists involved in routine monitoring of workers in the nuclear field and members of the public exposed to radioiodine released into the environment.

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Abstract  

The blood serum is the fluid medium through which most of the minerals are absorbed into the human body and get metabolized. The concentrations of Th in blood serum is in equilibrium with the content of Th in human body and therefore could reflect its content in the body. The daily intake (ingestion and inhalation) and the corresponding concentration of Th in blood serum of a group of subjects living in the high-background (monazite) area of Kerala State were measured and compared with the daily intake and corresponding blood serum concentrations of Th in three other groups of subjects namely: (1) those living in normal background area, (2) administrative staff working in Thorium Plant but not directly exposed to Th and its compounds, and (3) the occupational workers from Thorium Plant working for a time period in the range15–30 years. The Th concentration in the blood serum of subjects from high background area were found to be only marginally higher in comparison to the similar data from normalbackground area, which indicated that internal exposure due to Th to the subjects living in high background is quite low.

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