A review of edible mushroom radioactivity

The review deals mainly with the situation in Europe where wild-growing mus hrooms are widely consumed as a delicacy and some species have been found t o be extensively contaminated by radioactive fallout from the Chernobyl dis aster in 1986. The natural isotope K-40 usually causes activities of 0.8-1. 5 kBq kg(-1) dry matter. Activities of Cs-137, from nuclear weapons testing , below 1 kBq kg(-1) dry matter, were commonly reported until 1985. The sit uation changed dramatically after the Chernobyl accident and activities up to tens of kBq kg(-1) dry matter of Cs-137 and to a lesser extent of Cs-134 were observed in the following years in some edible species. Among the hea vily accumulating species belong Xerocomus (Boletus) badius, Xerocomus chry senteron, Suillus variegatus, Rozites caperata and Hydnum repandum. Activit y 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 c onsumption contributed up to 0.2 mSv to the effective dose in individuals c onsuming about 10 kg (fresh weight) of heavily contaminated species per yea r. The radioactivity of cultivated mushrooms is negligible. Contamination c an be considerably decreased by soaking or cooking of dried or frozen mushr oom slices. Animals, such as deer, eating mushrooms, have elevated levels o f radionuclides in their tissues. (C) 2001 Elsevier Science Ltd. All rights reserved.