An Alternative Approach to the Excess Lifetime Cancer Risk and Prediction of Radiological and Cancer Risks Caused by Terrestrial Radiation, Case of Isparta/Turkey

Abstract

Abstract There are more or less radioactive elements in the rocks and sediments, formed especially in volcanic regions. There may be a radiological risk for people residing on and around rocks or sediments where radioactive elements are very high. Among these radiological risks, the most important parameter that is determined the amount of death from cancer caused by the natural environment of human beings is known as the excess lifetime cancer risk. The excess lifetime cancer risk is presented in the literature with the empirical relationship. An alternative relationship for the excess lifetime cancer risk was developed in this study. This relationship includes radiological risk parameters and the average life expectancy and does not require a coefficient recommended by organizations. An application area was chosen to compare the results of the relationship developed by this study and the relationship available in the literature. This area included an area of approximately 12.5 km2 in and around the Çünür district of Isparta province in Türkiye, and gamma-ray spectrometry studies were carried out at 270 different points. In addition, the study area was evaluated in terms of radiological risk. For this, radioactive elements (U, Th, and K) were directly measured on the geological material (trachyandesite, flysch, limestone, and soil) using a gamma-ray spectrometer device. Maps were created to compare the outcomes of excess lifetime cancer risk determined with the new approach and calculated using the existing relationship in the literature. Also, the calculated radiological risk parameters were mapped to evaluate the study area in general. In addition to these, the relationships between each other the radioactive elements and the relationships between the radioactive elements and the radiological risk parameters were investigated and statistical analyses were made. Further, the number of people affected by the excess lifetime cancer risk in the study area was estimated based on both the relationship in the literature and the new approach. The results from both relationships are compatible with each other. Therefore, there is no need for the coefficient suggested by different organizations. As a result, it is understood that gamma rays caused by radioactive elements have harmful effects on human health, especially for people settling in volcanic regions. For this reason, radiological risky areas should not be preferred to choose a place of residence in city plans.