Risk Assessment of Public Gamma Radiation in Some Provinces of Iran

Introduction: Humans are continuously exposed to ionizing radiation. In order to evaluate health hazards, the measurements of background radiation in most countries have special importance. Material and Methods: The measurements were carried out by an Ion Chamber Survey Meter (X5C plus), during daylight in 2016. The collected and reported data were based on two ways. Firstly, the measurements of gamma background radiation were performed directly in indoor and outdoor places of five areas, including north, south, west, center, and east, in 11 cities of South Khorasan province, Iran. Secondly, the related data of other studies were used for several provinces of Iran. Results: According to the obtained results, the maximum and minimum of annual effective gamma dose were 0.72 and 0.34 nSvh^-1 in Asadabad and Tabas, Iran, respectively. The maximum and minimum of annual effective gamma dose were 0.84 and 0.27 nSvh^-1 in Hamedan, as well as Chaharmahal and Bakhtiari, Iran, respectively. Conclusion: The average values of the annual effective dose and estimated excess lifetime cancer risk (ELCR) were 0.60 nSv and 2.11×10^-3, respectively, which were higher than the amounts of the world average. The calculated ELCRs for all Iran provinces were higher in comparison to the world average value of 0.25×10^-3.