A review of edible mushroom radioactivity

Abstract

Abstract The review deals mainly with the situation in Europe where wild-growing mushrooms are widely consumed as a delicacy and some species have been found to be extensively contaminated by radioactive fallout from the Chernobyl disaster in 1986. The natural isotope 40K usually causes activities of 0.8–1.5 kBq kg−1 dry matter. Activities of 137Cs, from nuclear weapons testing, below 1 kBq kg−1 dry matter, were commonly reported until 1985. The situation changed dramatically after the Chernobyl accident and activities up to tens of kBq kg−1 dry matter of 137Cs and to a lesser extent of 134Cs were observed in the following years in some edible species. Among the heavily accumulating species belong Xerocomus (Boletus) badius, Xerocomus chrysenteron, Suillus variegatus, Rozites caperata and Hydnum repandum. Activity concentrations have been affected by several environmental factors, such as rate of soil contamination with fallout, the horizon from which mycelium takes nutrients, soil moisture and time from the disaster. Wild mushroom consumption contributed up to 0.2 mSv to the effective dose in individuals consuming about 10 kg (fresh weight) of heavily contaminated species per year. The radioactivity of cultivated mushrooms is negligible. Contamination can be considerably decreased by soaking or cooking of dried or frozen mushroom slices. Animals, such as deer, eating mushrooms, have elevated levels of radionuclides in their tissues.