Assessment of Background Radiation, Annual Effective Dose and Excess Lifetime Cancer Risk in Gonabad City

Humans are always exposed to ionizing radiation from their environment, which can have destructive effects. This study aimed to measure background gamma radiation and estimate annual effective dose and excess cancer risk in Gonabad city.

The dose rate due to indoor and outdoor background radiation was measured by RDS-30 radiation survey meter at five zones on the map, including North, South, East, West, and center. Then, the annual effective dose and excess lifetime cancer risk were calculated by associated equations.

Mean dose rates for outdoor and indoor spaces were 0.111 µSv/h and 0.139 µSv/h, respectively. The mean background dose rate of indoor space was significantly higher than that of outdoor space. Annual effective dose and excess lifetime cancer risk were obtained as 0.817 and 2.85×10-3, respectively.

Background radiation dose, annual effective dose, and cancer risk for Gonabad city were higher than global ones. Further investigations are needed to encompass internal background radiation doses in annual effective dose.