Natural radionuclides and assessment of radiological hazards in different geological formations in Khammouan province, Laos

The 226Ra, 232Th (228Ra), 40K activity concentrations in soil distributed in 67 points belonging to different geological formations in Khammouan, Laos were measured using HPGe detector. The results showed that the activity concentration varies from (6.0 ± 0.61) Bq/kg to (68.5 ± 8.0) Bq/kg, (8.7 ± 1.0) Bq/kg to (78.9 ± 8.3) Bq/kg, (32.1 ± 3.1) Bq/kg to (812 ± 63) Bq/kg with the mean values of (32.2 ± 1.7) Bq/kg, (41.6 ± 2.2) Bq/kg, (279 ± 24) Bq/kg for 226Ra, 232Th (228Ra), 40K respectively. The highest and lowest average activities were found at cPz2 (Middle Paleozoic) and Mz1 (Lower Mesozoic) formations respectively. With regard to radiation hazards, the 232Th (228Ra) concentration has a major contribution to the Raeq. In general, in the study area, the activity concentration of natural radionuclides has an insignificant effect on human health. © 2021, Akadémiai Kiadó, Budapest, Hungary.