الفهرس 
Introduction and Theoretical BackgroundOnly 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.
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.