Uptake and accumulation of 137Cs by upland grassland soil fungi: a potential pool of Cs immobilization

Reports of high concentrations of fallout radiocaesium in basidiomycete fruit bodies after the Chernobyl nuclear reactor accident and speculation that fungi could be long-term 137Cs accumulators led us to ask if fungi could be long-term 137Cs accumulators. We used six common upland grassland species to try to estimate their importance in the immobilization of 137Cs. Uptake of Cs by these species ranged from 44 to 235 nmol Cs g−1d.w. h−1. Efflux studies indicate that more than 40% of the Cs taken up is bound within the hyphae. We estimate that the fungal component of the soil could immobilize the total radiocaesium fallout received in upland grasslands following the Chernobyl accident.