Evaluation of Mercury Contamination in Fungi Boletus Species from Latosols, Lateritic Red Earths, and Red and Yellow Earths in the Circum-Pacific Mercuriferous Belt of Southwestern China

On the occurrence, origin, and intake of the nuclides, 210Po and 210Pb, 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 ²¹⁰Po, and beta-emitting ²¹⁰Pb, 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 ²¹⁰Po activity concentration levels were 0.36 Bq kg^-1 dry weight in the core and 12.0 Bq kg^-1 dw in the shell; ²¹⁰Pb activities were 0.43 and 9.84 Bq kg^-1 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^-1 dw from ²¹⁰Po decay and from 0.11 to 1.52 µSv kg^-1 dw from ²¹⁰Pb decay. Corresponding values for shell ranged from 0.80 to 42.4 for ²¹⁰Po and from 0.53 to 13.6 µSv kg^-1 dw for ²¹⁰Pb. In general, the intake of W. cocos sclerotia varies between consumers, but this would not significantly change the effective radiation doses from ²¹⁰Po and ²¹⁰Pb isotopes. The consumption thus appears to be safe from a radiological protection point of view.