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1.
Health Phys ; 86(3): 303-7, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14982231

RESUMO

The accumulation of certain elements in vitally important media such as water, soil, and food is undesirable from the medical point of view. It is clear that the fertilizers vary widely in their heavy metals and uranium content. A shielded high purity germanium HPGe detector has been used to measure the natural concentration of 238U, 232Th, and 40K activities in the phosphate fertilizer and its components collected from Abu-Zaabal fertilizers and chemical industries in Egypt. The concentration ranges were 134.97-681.11 Bq kg(-1), 125.23-239.26 Bq kg(-1), and 446.11-882.45 Bq kg(-1) for 238U, 232Th, and 40K, respectively. The absorbed dose rate and external hazard index were found to be from 177.14 to 445.90 nGy h(-1) and 1.03 to 2.71 nGy y(-1), respectively. The concentrations of 22 elements (Be, Na, Mg, Si, P, S, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Zr, Mo, Cd, Ba) in the samples under investigation were determined by inductively coupled plasma optical-emission spectrometry (ICP-OES). The results for the input raw materials (rock phosphate, limestone and sulfur) and the output product as final fertilizer are presented and discussed.


Assuntos
Fertilizantes/análise , Fosfatos/análise , Radioisótopos de Potássio/análise , Proteção Radiológica/métodos , Radiometria/instrumentação , Radiometria/métodos , Poluentes Radioativos do Solo/análise , Tório/análise , Urânio/análise , Egito , Contaminação Radioativa de Alimentos/prevenção & controle , Doses de Radiação
2.
Appl Radiat Isot ; 60(1): 105-9, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14687643

RESUMO

Natural radioactive materials are present in all geological rocks in varying amounts, they are easily mobilized in the environment, and can reach hazardous radiological levels under certain conditions, requiring precautions to be taken. The present study deals with 50 geological samples of local (Tushki and Kalabsha in upper Egypt) and imported (southeast Asia and Turkey) kaolin types. The samples were analyzed by gamma-ray spectroscopy using a HPGe detector. The activity concentrations of 232Th and 238U series and 40K and the contents (in ppm) are given. The radium equivalent activity varied from 187.8 to 10185.19 Bq/kg. 137Cs was found in a range of 0.23-8.5 Bq/kg, for the local samples. The kaolin in Tushki area was suitable for industrial use.


Assuntos
Caulim/análise , Radioisótopos/análise , Egito , Sedimentos Geológicos/análise , Radioisótopos de Potássio/análise , Radioatividade , Espectrometria gama , Tório/análise , Urânio/análise
3.
J Environ Sci (China) ; 15(4): 570-6, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12974322

RESUMO

Major and trace element in seven different kinds of milk powder were studied. The concentration of 24 elements were determined by ICP-OES method, from these elements 9 elements determined by INAA. The determination of trace element contents of foodstuffs, especially milk as daily drink for all peoples age which being a complex food has great importance. The elemental analysis of milk is important both as an indicator of environmental contamination and because milk is a significant pathway for toxic metal intake and a source of essential nutrients for humans. The major elements are Ca, K, Mg, Na, P and S. While trace element are B, Ba, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Sb, Se, Sn, Sr, V, W and Zn. ICP-OES technique is shown to be a powerful tool for trace determinations in powder samples. This is shown by its use for analysis of a series of the milk powders mentioned and comparative results of other direct technique such as instrumental neutron activation analysis. Analysis of both standard reference material A-11 milk powder and NBS Orchard leaves for quality accurance had been completed, and used for a relative method calculate. The importance of the major and trace elements to human health was discussed.


Assuntos
Leite/química , Oligoelementos/análise , Animais , Humanos , Análise de Ativação de Nêutrons , Pós/química , Saúde Pública , Espectrofotometria Atômica
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