Accumulation and distribution of ⁴⁰K in the chaga mushroom

抄録

This work is the first report on activity concentrations of ⁴⁰K in Inonotus obliquus sampled in a virgin forest of Siberia. The results have shown that the chaga conk is characterized by high activity concentrations of ⁴⁰K, averaging 1,641 Bq/kg dry weight (DW) and peaking at 3,502 Bq/kg DW. Activity concentrations of ⁴⁰K in chaga conks have been defined to increase from the near-trunk stratum to the crust of the conk with increased exposure to the solar radiation. Our measurements have revealed the samples to be mildly contaminated with ¹³⁷Cs. Intensive assimilation of ⁴⁰K by chaga conks has been shown as a normal and innate feature of the wild chaga mushroom.