¹³⁷Cs и ²⁴¹Am in Narovlya District of Belarus: Updated Radiological Assessment of the Local Existing Exposure Situation

Objective. To provide an assessment of 137 Cs and 241 Am levels in Narovlya district of the Gomel region adjacent to the Polesie State Radiation-Ecological Reserve Materials and methods . The data on soil and food contamination is obtained for 113 private backyards locatedin 32 villages of the Narovlya district. A gamma-spectrometry technique was used to measure 241 Am in soil and 137 Сs in soil and food samples. 241 Am in food samples was measured via a radiochemical method with the use of alpha-spectrometry measurement. Results . The values of specific activity of radionuclides in the soil of all sites range from 230 to 2770 Bq/kg for 137 Сs and do not exceed 10 Bq/kg for 241 Am. The specific activities of 137 Cs in food samples range from 3 to 160 Bq/kg, and the values of 241 Am concentration stay within units or tens of millibecquerels per 1 kilo of a product. The estimates show that, considering the present-time 241 Am contamination of locally produced foods, its share in the total internal radiation dose is not likely to be higher than 0.1% from both radionuclides, 137 Сs and 241 Am. However, inhalation of 241 Am can increase its share in the total internal dose up to 3%. Consumption of 137 Сs-contaminated foodstuffs may potentially cause 97 to 100% of the total internal radiation dose in the district. Conclusion . At the present stage of the radioecological context in the existing exposure situation the major contribution to the public internal exposure is 137 Сs intake through consumption of contaminated food that produced locally; its contribution is more than 97% of the total internal dose received by the Narovlya district residents. It is recommended to minimize any type of fieldworks on the dry and dusty soils that can cause excessive inhalation of the alpha-emitting 241 Am.