Integrated Assessment of Soil, Airborne and External Gamma Radiation Indicators in Uranium Industry-Affected Areas of Uchkuduk, Uzbekistan

The soil radionuclide inventory, most often monitored in uranium industry areas, may not reflect the inhalation hazard. We tested this in Uchkuduk, Uzbekistan, at ten co-located points in each of a uranium sorption recovery section, a mill tailings site and the residential area, measuring 226 Ra, 232 Th and 40 K in soil, the radium equivalent activity ( Ra eq ), the ambient dose equivalent rate H *(10), the equilibrium equivalent radon concentration ( EERC ) and the long-lived alpha activity ( LLAA ) of aerosols. The tailings site had the highest 226 Ra, Ra eq and H *(10) (up to 5.85 µSv h − 1 ), but outdoor EERC and LLAA were no higher than at the sorption section, where indoor EERC reached 46 Bq m − 3 . Outdoor EERC followed 226 Ra at the sorption section and in the residential area, whereas at the wind-exposed tailings site only LLAA did (ρ = 0.89–0.92). Airborne indicators should therefore be measured directly rather than inferred from soil and gamma surveys.