Estimation of radioecological parameters of soil samples from a phosphatic area

Abstract

The activity concentrations of natural radionuclides (226Ra, 232Th, and 40K) for a set of 31 agricultural soil samples from the Nile River banks in the area of El-Sebaiya city, Aswan Governorate, Egypt were measured by gamma-spectrometry. The study revealed that the average activity concentrations of natural radionuclides 226Ra, 232Th, and 40K were 23.2 ± 2.8Bq/kg, 21.1 ± 2.8 Bq/kg, and 218.6 ± 3.7 Bq/kg, respectively. The obtained results of the activity concentrations are within the range of values reported for neighbouring areas in Egypt. The values obtained for the hazard indices and the representative level index in all sampling sites were lower than unity, showing that there is no significant risk arising from the exposure to the soil in the studied area.The absorbed dose rate and annual effective dose in air outdoors and indoors were calculated from 226Ra, 232Th, and 40K in soil, the average values being 32.64 nGy/h, 40.06 µSv, and 160.25 µSv, respectively. The absorbed dose rate at the eastof El-Sebaiya city is higher than that obtained for the west because of higher concentrations of tri-calcium phosphate in the soil.The studied area is not significantly affected by the industrial activities, except for a few isolated spots.