Radiation hazard indices associated with natural radioactivity in building materials in Montenegro

Abstract Eleven building materials (95 samples in total) have been analyzed for 226Ra, 228Ra (232Th series), and 40K activity using High Purity Germanium (HPGe) spectrometry, and concentrations are found to be in the range (2.2–549), (0.3–161), and (2.7–1034) Bq kg−1, respectively. Statistical analyses showed a moderate positive linear correlation between 226Ra and 228Ra, and significant differences in the mean radionuclide concentrations among ceramic tile, brick, granite, and the other studied materials. Radiation hazard indices (radium equivalent activity, external and internal hazard index, activity concentration index, dose rate) were determined to assess the potential health risk. Several samples of granite, ceramic tile, and brick showed individual indices exceeding the recommended maximum values. The discriminant analysis clearly separated granite, brick, and ceramic tile from the other materials, while the principal component analysis showed that the component explaining >84% of the data variance is strongly correlated with loading of 226Ra.