Radoslava Lazarova and Milena Hristozova
Agricultural Academy, „ N. Poushkarov“ Institute of Soil Science, Agrotechnologies and Plant Protection, Testing Laboratory of Radioecology and Radioisotopes Research, 1331 Sofia, Bulgaria
Lazarova, R. & Hristozova, M. (2025). Distribution of 137Cs in soils and wild mushrooms from Bulgaria. Bulg. J. Agric. Sci., 31(5), 905–909
The content of technogenic 137Cs was studied in soils and wild mushrooms from Bulgaria.
The specific activity of the radionuclide varied between 2.0±0.5 and 35±3 Bq/kg in the soils from Northern Bulgaria and between 4±1 and 270±10 Bq/kg in the soils from southern Bulgaria. The significant standard deviation calculated indicated firm heterogeneity in pollution, particularly in the southern mountainous part of the country.
The highest accumulation of Cs-137 was found in wild mushrooms from the species Hydnum repandum – 890±90 ÷ 1500±50 Bq/kg, Hydnum imbricatum – 1250±60 ÷ 2860±150 Bq/kg, and Cantharellus cinereus – 890±90 ÷ 2030±100 Bq/kg. Lower values were measured in Boletus edulis – < 1÷55±5 Bq/kg (fresh weight) and 10±2 ÷ 400±20 Bq/kg (dry weight), and Cantharellus cibarius <1 to 55±6 (fresh weight) and 15± to 190±20 Bq/kg dry weight. The lowest levels of radiocaesium were recorded in Marasmius oreades – <1 to 10±2 Bq/kg, Morchella esculenta – <1 to 20±3 Bq/kg, and Craterellus cornucopioides – <1 to 20±4 Bq/kg.
The annual effective dose from consuming mushrooms with 137Cs content exceeding the EU limit of 600 Bq/kg was calculated. It was found that its contribution to the annual effective dose from all radioactive sources is insignificant, and it is not hazardous to the population from a radiological point of view. However, their regular consumption is not recommended.