الفهرس 
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Abstract
Abu Zaabal is one of the areas in Egypt that could be subjected to contaminants release from industrial activities to air or water with traceable amounts of trace elements and/or radionuclides. The main activities in the area that causes such releasewhere our study is focus on; are Phosphate Fertilizer Factory, and the Nuclear Research Reactor in Inchas area.
Twenty soil samples and its corresponding plants (20 samples) were collected and examined for trace elements (Cu, Co, Cd, Cr, Mn, Ni, Pb, Fe, V, and Zn). Contour maps were plotted for the distribution of these elements within the study area.
Natural radioactivity of three radionuclide (R-226, Th-232, K-40) and one artificial (man-made) radionuclide (Cs-137) was measured in the collected soil and plant samples in order to study the effect of these radionuclides on the environment (soil, plant).
To study the impact of radionuclides; radiation hazard indices were calculated including the annual effective dose rate, the external and internal dose rate.
The obtained results of trace elements concentration in soil samples showed that the detected elements are lower than the worldpermissible limits for soil samples. Whereas, in plant samples the accumulation differ from element to element specially in copper and vanadium which showed higher concentration in comparison with the permissible limits of world ranges for plants.
Natural radioactivity concentrations in soil samples lie in the
average ranges 18.7±2.4, 13.8 ± 1.9, and 190±1.9 Bq/Kg for Ra-226, Th-232 and K-40 respectively. These concentrations are considered safe to human and environment.
The man made radionuclide Cs-137 concentration in soil samples is very low, ranged from 0.14 ± 0.03 to 0.84 ± 0.12 Bq/Kg.
In plant samples the obtained data showed that R-226 and Th-232 concentration was low in comparison with its soil.On the other side, the concentration of K-40 in plant samples the av. concentration reaches 740 ± 21 Bq/Kg. This value is found to be 3 times greater than its soil. Cs-137 can’t reach the detection limits of the instrument for all plant samples which mean that it absent or in concentration can’t be traced.
The gamma-ray radiation hazards due to the specified radionuclides were assessed by three indices, i.e., the radium equivalent activity, Raeq, the representative level index, Ir, and the external hazard index, Hex.
The highest value of radium equivalent in soil samples was 89.57 Bq/Kg and the lowest Raeq value was 18.14 Bq/kg with mean concentration 53.12 Bq/kg.
Absorbed dose rates, D ranged from 8.8–42.38 nGy/h with average values 25.32 nGy/h which considered lower than the world average rate (55 nGy/h).
The highest annual effective dose rate value found to be 52 μSv/year. Whereas, its lowest value reached 10.8 μSv/year. The world average annual effective dose equivalent (AEDE) from outdoor terrestrial gamma radiation is 460μSv/year (UNSCEAR 2000).
This means that the external and internal hazards indices were lower than unity which considered being safe for public.
The present study showed that the soil collected from Abu Zaabal area had various radionuclide contents within the average world values. The effect of phosphate fertilizer factory is almost safe. The corresponding gamma radiation hazard indices and annual effective dose were below those of the limits considered acceptable.
Regarding to the obtained data we can concluded that, the study area is considered to be safe in the context of public health with respect to radioactivity. The obtained results can be used as data base radioactivity background at Abu Zaabal area.