Quantification of natural radioactivity, radon levels, and radiological health hazards in soil from seismic fault zones

Abstract

The earth’s crust is divided into fifteen tectonic plates, with Pakistan situated on a convergent boundary between the Eurasian and the Indian plates. This has resulted in massive mountain ranges and faults, including the Himalayas and Hindu Kush Mountains. Soil sampling was conducted at eight specific places around the point of convergence of the Indian and Eurasian tectonic plates (Main Boundary Thrust) in Margalla, Islamabad. These sites were purposely chosen due to the presence of fault lines that are prone to seismic activity. The study involved quantifying the natural radioactivity of ²²⁶Ra, ²³²Th, and ⁴⁰K in the soil along the Main Boundary Thrust near Islamabad, using an HPGe detector. In addition, the radon concentration was determined using a Rad7 alpha detector. The activity of ²²⁶Ra, ²³²Th, and ⁴⁰K was 17 ± 6, 16 ± 8 and 167 ± 79 Bqkg⁻¹, respectively. The radon concentration at 10, 20 and 30cm depths was measured using a Rad-7 detector. The measured activity of radionuclides was used to quantify the health hazards posed by the radionuclides upon exposure.