Natural radioactivity in soil samples from selected areas in Nineveh governorate, Iraq

Abstract

The activity distribution of natural radionuclides 232 Th, 226 Ra, 40 K and 137 Cs were determined in soil samples. The samples were collected from four different regions in Nineveh governorate northwest of Iraq (Tall Kayf, Badush, Al-Hamdaniya, Hammam Al-alil) and measured by the gamma-ray spectrometry with high purity germanium (HPGe) detector with relative efficiency 50 %. The specific radioactive activity of the samples was in the range of 1.75-45.56, 8.63-43.72, 147.92-502.49 and MDL-69.32 Bq/kg, respectively, at the selected areas. The calculated hazard indices that estimate the potential radiological health risk such as radium equivalent activity (Ra eq) were in the range 40.33-122.12 Bq/kg. The absorbed dose rate in the air was also calculated for the samples and it was in the range 20.51-56.72 nGy/h. External hazard index (H ex) is in the range 0.11-0.33, internal hazard index (H in) is in the range 0.13-0.4 and gamma index was 0.32-0.89. The annual effective dose equivalent (AEDE), annual gonadal dose equivalent (AGDE), and excess lifetime cancer risk (ELCR) were also calculated and their ranges were 25.15-69.56, 151.63-396.05 and 0.09•10-3-0.24•10-3 respectively. This study showed that there is no radiation hazard to the public due to natural radionuclides in the selected areas.

Determination of the Natural Radioactivity and Heavy Elements from Some Soil Samples

“…(3)(4)(5) shows that the average value of radiation hazards is less than the recommended value. [13] 84 [14] ˂2 [19] 1 80 [19] 420 [19] 0.29 [19] 1.16 [19] <300 1 [19] Table 3 : Natural radioactivity of some surrounding countries The Sits 3 Basic statistical analysis : Basic statistical analysis, such as maximum, minimum, standard deviation, variance, and skewness, can be used to describe the statistical properties of radionuclide activities, as shown in Table 5. The standard deviation of 232 Th, 226 Ra, and 40 K from all measurements is less than the mean value, which indicates an irregular distribution.…”

Natural Radioactivity Evaluation and Radiological Peril in some soil specimens of Al-Taimeem Area in Al-Anbar Province, Iraq

“…It is defined as the quantity of radioactivity in a material or the association between the mass of radiological material and the effectiveness. The qualitative activity for identified radionuclide can be given by [9]:…”

“…The increase in the rate of absorbed dose arises from the gamma-ray radionuclides which are present in very small quantities in the soil. The estimation of the absorbed gamma dose is based on the qualitative activity of the radionuclides, So, D γ (nGy/h) can be given by [9]:…”

“…Shows internal respiration of alpha particles transferred from short isotopes, e.g., 222 Rn and 232 Th accompanied by γ-rays and can be expressed in terms of the internal risk indicator (H in ), Which can be illustrated by the following relationship [9]:…”