الفهرس 
TitleOnly 14 pages are availabe for public view
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Abstract
Man is constantly exposed to radiation from both natural and artificial sources. Both
minerals and raw materials contain natural radionuclides, the most critical of which, for
safety purposes, are the radionuclides of the 238U and 232Th decay series and 40K. NORM
are included in fertilizers that can lead to elevated levels in vegetable plant (Cabbage-
Lettuce-Rocca-Mallow), including 238U, 226Ra 40K, and 137Cs. This can result in increased
exposure to human and animals through the ingestion of these crops, and fertilizers may
contain extreme toxic heavy metals such as As, Pb and Cd that trigger certain diseases such
as cancer, brain damage.
The aim of the study was to make measurement of radioactivity released into different
environmental compartment (plant and soil) caused by use of phosphate fertilizers.
This study included 53 samples divided into:
Soil samples: 20 samples (10 before and 10 after fertilization)
Plant samples: 20 samples (10 before and 10 after fertilization)
Water samples: 10 samples of irrigation water
Fertilizer samples: 3 samples
Detected radionuclides were done by High purity germanium detector (HPGe) and
used inductively coupled plasma optical emission spectroscopy (ICP-OES) to calculate
heavy metal concentration.
Our results showed that
In soil, the mean concentration of 226Ra after and before fertilization is greater than
the global average value concentration. Approximately 80% of the values reported
are higher than the world average. But about 20% of the 40K reported values are
greater than the world average.
The soil would become invalid either for agricultural purposes or as aggregates of
building material as a result of Raeq results for before and after fertilization shown
after 104 times the fertilizer has passed.
The mean value concentration of 226Ra in plant samples before and after fertilizations is
higher than the average worldwide. Mean value concentration of 40K after fertilization
is greater than before fertilization and average worldwide concentration.
In pre-fertilization, the annual internal effective dose due to 226Ra intake is higher
than the levels of normal background areas recorded by UNSCEAR and the annual
internal effective dose due to 40K intake is higher than the levels of normal
background areas reported by UNSCEAR, with the exception of > 17 years and
from (12-17 yrs). But annual internal effective dose due to 226Ra, 40K and 228Ra
intake are greater than average background levels after fertilization.
Average concentration levels of As and Cd elements in plant samples before and
after fertilization are larger than permissible limit recommended by WHO. Pb
element level in plant samples after fertilization is larger than permissible limit.
Summary, Co nclusion and Recommendation
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6.2. Conclusion
According to the present study, we can conclude the following:
After fertilization, the total concentration of 226Ra in soil and plant samples
increases than before fertilization, which is greater than the world average.
After fertilization, the average 40K concentration in plant samples increases than
before fertilization.
The soil would become invalid either for agricultural purposes or as aggregates of
building material from Raeq’s results after 104 times fertilization has passed.
Annual internal effective dose due to intake of 226Ra, 40K and 228Ra from this
outcome will contribute to cancer risk, which is determined by considering a linear
dose-effect relationship with no threshold as per the ICRP method.
Regarding heavy metals concentration in plant samples, before and after fertilization, the
concentration of As as well as Cd are larger than maximum allowable limit. While Pb
element in plant samples after fertilization is higher than permissible limits.