Preliminary assessment of the influence of fault structures on radon potential (a case study of Sliven District, Bulgaria)

Abstract

Indoor radon exposure is recognized as a significant cause of lung cancer, as shown by various epidemiological studies. One possible pathway for radon transport is through faults, where radon can escape into fractures and open spaces in rocks. Numerous studies link fault systems to elevated radon levels at the surface or within buildings. In Bulgaria, research on geogenic radon potential at a regional scale, especially for RPA (Radon Priority Areas) identification, is still in its early stages. This study aims to further investigate radon soil gas concentration on a regional scale and its correlation with fault systems in Sliven Province. In the study area, the majority of radon soil gas concentration measurements with higher values coincide with fault systems. However, the mechanisms of radon gas transport along these structures remain poorly defined and appear to be complex.