Determination of radioactivity levels of soil samples and the excess of lifetime cancer risk in Rize province, Turkey

Background: Turkey, especially the northern part of it, was one of the countries which were contaminated by the Chernobyl accident. Rize is a city located in the Northeastern district of Turkey which was heavily influenced by the Chernobyl nuclear accident. Materials and Methods: In this study, the ac vity concentra ons of natural (^226Ra, ^232Th, ^40K) and ar ficial (^137Cs) were measurements in soil samples collected from 132 different points in Rize province of Turkey using gamma spectrometry with a high-purity germanium detector. Results: The average ac vity concentra ons of ^226Ra, ^232Th and ^40K were found to be 85.75±11.77, 51.08±9.42, and 771.57±37.65 Bq/kg in soil samples, respec vely. In order to evaluate the radiological hazard of the natural radioac vity, radium equivalent ac vity (Raeq), representa ve level index (Iγr), the external hazard index (Hex), the total absorbed dose rate (D), the annual effec ve dose equivalent (AEDE) and excess life me cancer risk (ELCR) have been calculated and compared with the interna onally approved values. Conclusion: The outdoor air absorbed dose rates (D) due to terrestrial gamma rays for soil have been calculated because of agricultural area and living in the surrounding. It is important to determine background radia on level in order to evaluate the health hazards. Annual effec ve gamma doses and the life me risks of cancer were higher than the world’s average. Moreover compared to the World’s average, the life me risk of cancer doubled for most of the localities.