On the occurrence, origin, and intake of the nuclides, Po and Pb, in sclerotia of Wolfiporia cocos collected in China.

The dried sclerotium of the fungus Wolfiporia cocos is edible and has medicinal value. This study aimed to understand the accumulation of radioactivity arising from the alpha Po, and beta-emitting Pb, in the sclerotium's shell and core and assess a potential effective dose for consumers. Sclerotia were collected in the wild and from cultivars in China's Anhui and Yunnan provinces. The mean values of Po activity concentration levels were 0.36 Bq kg dry weight in the core and 12.0 Bq kg dw in the shell; Pb activities were 0.43 and 9.84 Bq kg dw, respectively. The potential effective radiation doses from core layers (as a major raw material of the sclerotium) ranged from 0.13 to 3.43 µSv kg dw from Po decay and from 0.11 to 1.52 µSv kg dw from Pb decay. Corresponding values for shell ranged from 0.80 to 42.4 for Po and from 0.53 to 13.6 µSv kg dw for Pb. In general, the intake of W. cocos sclerotia varies between consumers, but this would not significantly change the effective radiation doses from Po and Pb isotopes. The consumption thus appears to be safe from a radiological protection point of view.