Environmental Nuclear Studies of Natural and Man-Made Radioactivity at Hebron Region in Palestine

Abstract

The activity concentrations of naturally occurring and man-made radioactive

materials in soil samples collected from 20 locations at different

depths from the northen as well as the southern parts of Hebron province

were measured using gamma-ray spectroscopy. The average of the measured

concentrations for 238U series, 232Th series, 40K isotope, and 137Cs isotope

in the northen region are found to be 32.9, 22.9, 225.9 and 5.5 Bq/kg,

respectively; while in the southern region, the avearge of the mneasured

concentration levels are 65.6, 71.3, 447.1 and 7.5 Bq/kg, respectivly. On one

hand, the averge of the concentration levels for all inspected nuclides in the

northen area are generally found to be lower than the assigned international

radioactivity concentration levels. On the other hand, the concentration

levels for most nuclides in the southen area are found to be higher than

the assigned interntional concentration levels. The investigated zone areas

may be classified as high to moderate natural concentration levels. The

absorbed dose rates (Dr), the radium equivalent activity (Raeq), the external

hazard index (Hex), and the gamma level index (Iγ) for the soil samples are

also investigated. The obtained results may be considered to be as reference

values that can be used and as baseline data for drawing a radiological map

of the regions under consideration. The presence of 137C in the soil samples

is mainly attributed to fall-out of the usage of technological nuclear aspects

and artificial nuclear processes.