الفهرس 
Chapter oneOnly 14 pages are availabe for public view
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Abstract
In this work, the specific activities of natural radionuclides in synthetic fertilizers and some soil samples were studied using gamma spectroscopy and sealing technique. Also, radon concentrations in 42 fertilizers and soil samples were measured by passive technique detector (CR-39). Radon exhalation rates in terms of mass and area were also calculated using “sealed can technique” using CR-39 SSNTDs.
The average areal exhalation rates of radon are found to be (9.6±0.40, 11.40 ±0.90, 0.30±0.05 and 0.38±0.02) Bq m-2h-1 for waste product, phosphate fertilizers, chemical fertilizers and soil samples, respectively. Whereas, the mean average mass exhalation rates are estimated to be 0.30±0.02, 0.40±0.02, 0.01±0.001 and 0.01±0.001 Bq kg-1 h-1 for waste product, phosphate fertilizers, chemical fertilizers and soil samples, respectively. 0. The average specific activity concentrations of 238U, 226Ra, 232Th and 40K in waste product samples were found to be 246.13±20, 474.47±30, 9.19±0.70 and 91.25±8.50 Bq kg-1, respectively. In phosphate fertilizer samples were found to be 295.29±20, 630±40, 7.31±0.50 and 39.63±2.50 Bq kg-1, respectively. For soil samples, the specific activity concentrations for 238U, 226Ra, 232Th and 40K, have average values of 14±1.50, 21±40, 12.8±1.20 and 218.9±20 Bq kg-1. Radiological hazard indices such as radium equivalent activity (Raeq), absorbed gamma dose rates (DR) at 1m above ground, annual external effective dose rate, annual effective dose equivalent (AEDE), internal hazard index (Hin), external hazard index (Hex) and annual gonadal dose equivalent (AGDE) were evaluated.
The value of radium concentration in all soil samples except for samples near the Abu-Zaabal factory is less than the permitted value of 370 Bq kg-1 authorized by organization for Economic corporation and development. The specific activity values of 238U,232Th and 40K in soil samples from Al-Ghabat village and in chemical fertilizers are lower than the recommended value of 50, 50 and 500 Bq kg-1, respectively, so no radiation hazard is considered with them. While phosphate fertilizers and soils surrounding Abu Zaabal factory are higher than the recommended value. Also, radiation hazard indices for phosphate fertilizers are high, so it is considered a risk to health.
The dealers and farmers dealing with phosphate fertilizers should take care as it contains high concentration of radionuclides. The Abu-Zaabal factory waste product must be removed safely as it contains the highest concentration of 238U. Finally, the results obtained from the two used techniques (SSNTDs and gamma spectrometer) are well correlated with each other and with other previous studies performed in Egypt.