An overview on radiometric assessment and excess lifetime cancer risk of soil in Pakistan by using High Purity Germanium (HPGe) detector.

Objectives The aim of this study is to compare the natural radioactivity and excess life time cancer risk (ELCR) factor of soil in different regions of Pakistan during last decade. Soil contains various elements and compounds including naturally occurring radioactive elements (238U, 232Th, 40K and 137Cs). Human being, animals and plants are in health risk by contaminations of natural radioactivity in soil and environmental radiometric pollution. Transferring of large amount of the natural radioactive elements in human body by nutrients may cause carcinogenic effects in human body. Pakistani soil has six types as Indus Basin Soil, Bongar Soil, Khaddar Soil, Indus delta soil, Mountainous soil and Sandy Desert Soil. In some northern region of Pakistan, naturally occurring radioactive rocks like uranuium-238 and iridium concentrations present in Gharwandi, Aram, Kingri S, Vitakri Fort Munro, Dera Bugti, Kohlu and Sibbi districts. Methods In this reviewed data, gamma rays spectroscopy used to determine the concentrations of 238U, 232Th and 40K with the help of High Purity Germanium (HPGe) detectors. Only the data of HPGe detector collected because of comparisons of different regions of Pakistan. Results and conclusions Mostly, different gamma rays energy peaks of relevant daughter radionuclides of radioactive element were used such as the energy peak lines of daughter radionuclides 214Pb (295.21 and 352 KeV) and 214Bi (609 and 1,120 KeV) used for calculating the 226Ra concentration in soil. In the recent study, it is concluded that average values of concentrations of natural radioactivity in soil in central and north regions of Pakistan are higher than permissible limit but found permissible range in south region of Pakistan. Mean values of ELCR factor were found higher, equal and lower in central, north and south regions than permissible limit, respectively. Generally, no serious health hazard due to natural radioactivity in soil were found.