الفهرس 
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Abstract
The aim of present study is to study the environmental impact of urbanization
and industrialization on natural radioactivity by evaluation of the radioactivity
concentration levels due to natural and artificial radionuclides in North Suez Canal
region. The study area is considered as one of the important, and developing industrial
area in Egypt. The evaluated data will show the trends in variation of these values to
the map of radioactivity levels in the surrounding environment. This map will be used
as reference information to assess any change in radioactivity background levels due
to any natural or artificial processes influences on the environment background
radiation. Gamma Spectroscopy analysis will be performed on the samples using a
Hyper-Purity Germanium Detector (HPGe) with a high level of resolution in a
passively shielded low background arrangement. A wide range of different gammaray
energy transitions lines associated with decays from the decay products of the 238U
and 232Th decay chains have been analyzed separately to obtain more statistically
significant overall results, under the assumption of secular equilibrium of the
radionuclides within these samples.
Soil, raw materials, and end product samples were collected from the studied
areas of the three factories (two concrete block factories and a chemicals factory) in
Port Said government. Thirty-three soil samples were collected from different zones
around the three factories besides two concrete block samples from El-Captain
factory. Also, three collected groups of different concrete blocks used in building
construction were utilized to evaluate the dose inside dwelling. The collected samples
were analyzed to determine the activity concentrations of 238U, 232Th, 40K and 137Cs by
using gamma ray spectrometry. The average activity concentrations 238U, 232Th and
40K were 9.66, 9.56 and 252.25 Bq/kg for soil samples, 20.59, 5.51 and 85.28 Bq/kg
respectively for raw materials samples, 20.1, 3.55 and 93.19 Bq/kg respectively for
two product samples. The artificial radionuclide, 137Cs, was not observed in
statistically significant amounts above the background level in the current study. The
40K activity concentration was observed to be slightly higher than the world average
value 400 Bq/kg reported by UNSCEAR, 2000. However, the average 238U and 232Th
concentration in soil samples of studied area was found to be similar to the world
average.
The data obtained from soil analysis were used to estimate radium equivalent,
absorbed dose rate, Gamma index and Alpha index. It was found that the average
values of radium equivalent activity and Gamma index in soil samples were 47.32 and
0.16 Bq/kg. Also, the average values of dose rate was 19.24 nGy/h and average values
of annual effective dose rate was 0.09 mSv/y. For raw materials and product samples
the average values of radium equivalent were 32.35 and 35.04 Bq/kg respectively,
where Gamma indices mean values were 0.12 and 0.13 Bq/kg, and the average values
of dose rate were 14.9 and 16.2 nGy/h respectively. The results indicate that the
radiation hazard from primordial radionuclides in most soil samples from the studied
area in the current work is not significant. The average values of radium equivalent
activity in all samples range from 9.39 to 120.81 Bq/Kg and the external hazard
indices ranged from 0.02 to 0.32 Bq/Kg.
Absorbed dose rates of block samples collected from El-Captain concrete block
factories were evaluated by using room model proposed by Allam K.A. with a
computer simulation using Monte Carlo calculation. Three common Egyptian public
rooms dimensions were selected in addition to the standard one. Annual Effective
Dose received (AED) by public living in the rooms was calculated. AED rates ranged
from 140 to 170 Sv/yr. Different wall widths from 5 to 50 cm with the same
materials composition were considered. Specific Effective dose rates due to 238U were
increased by 16.6%, 6.1%, 2.7% by increasing wall width from 5 to 20 cm
respectively, then it’s nearly stable after 20 cm. The same sequence of increase was
observed for the dose rate values due to 232Th and 40K. They were increased by
16.6%, 6.6% and 3% for Th series and by 18.4%, 7.4% and 3.3% for 40K isotope