A Method for Calculating Absorbed Dose in Lungs for Terrestrial Mammals From Radioactively Contaminated Atmospheric Air

A method is developed for calculating absorbed dose rates in lungs from chronic radionuclide inhalation by reference mammal animals of different sizes. Accumulation of radionuclides in lungs was estimated for permanent imbabitance of biota in the contaminated atmospheric air. Dose coefficients of absorbed dose rates in lungs were calculated for chronic inhalation of air, containing 1 Bq/m of radionuclides. Important role of inhalation exposure from long-lived alpha-emitting radionuclides is demonstrated. Conclusion was made on the necessity to account for the inhalation pathway in the impact assessment on non-human biota from the air contamination, and development of air quality control radiation levels, especially for long-lived alpha emitters. Estimation of lung dose rates to terrestrial mammals in the observation zone of PA “Mayak” (Southern Urals, Chelyabinsk region) demonstrated the dominant contribution of Pu in lung dose rate, exceeding 90% during time period 2004–2023.