Evaluation of radioactivity in the newly reclaimed soils and its association with soil properties

Abstract

The newly reclaimed soil has poor agricultural fertility in addition to being contaminated by excessive use of fertilizer, improper irrigation practices, and poor irrigation water quality. The radioactivity of farming soil and the radiological health risks to farm people in Qena Governorate, Egypt, were evaluated using natural radionuclide measurements (²²⁶Ra, ²³²Th and ⁴⁰K) from surface and subsurface soil samples collected in 15 locations. Both bivariate and multivariate statistics to investigate associations between radioactivity concentration and soil physicochemical properties. The findings indicate that the mean value for ²²⁶Ra, ²³²Th, and ⁴⁰K range from 5 ± 0.20 to 14 ± 0.7, 3 ± 0.20 to 14 ± 0.70, and 11 ± 0.50 to 72 ± 3.60 Bq Kg⁻¹, respectively. These results were compared to data reported from other countries and the global average. The concentrations of ²²⁶Ra, ²³²Th, and ⁴⁰K were found to be lower than the global average. Additionally, all samples underwent analysis for radium equivalent, absorbed gamma dose rate, annual effective dose, internal hazard index, external hazard index, gamma radiation hazard index, and excess lifetime cancer risk. The results of PCA analysis indicate that soil management practices and soil reclamation activities have an impact on the radioactivity level and distribution. Furthermore, physical, and chemical characteristics of the soil, especially texture, pH, and calcium carbonate, were revealed to be the primary determinants of radioactive concentrations in the soil, according to PCA and Pearson correlation analysis. The data will establish the initial concentration of naturally occurring radionuclides in the research area, providing valuable information for monitoring and evaluating potential environmental contamination within this locality.