Radioactive artificial (137)Cs and natural (40)K activity in 21 edible mushrooms of the genus Boletus species from SW China

This study, for the first time, presents the results of activity concentration determinations for (137)Cs and (40)K in a high number (21 species, 87 composite samples, and 807 fruiting bodies) of mushrooms of the genus Boletus from across Yunnan in 2011–2014 and Sichuan (Boletus tomentipes) using high-resolution high-purity germanium detector. Activity concentrations of (137)Cs demonstrated some variability and range from <4.4 to 83 ± 3 Bq kg(−1) dry biomass in caps and from <3.8 to 37 ± 3 Bq kg(−1) dry biomass in stipes, and of (40)K, respectively, from 420 ± 41 to 1300 ± 110 and from 520 ± 61 to 1300 ± 140 Bq kg(−1) dry biomass. No significant variations were observed regarding (137)Cs and (40)K activity concentrations among the same Boletus species from different sampling sites. No activity concentrations from (134)Cs were detected in any mushrooms. Internal dose rates estimated were from intake of 1 kg of mushrooms per annum for (137)Cs range for species and regions from around <0.0031 to 0.047 ± 0.003 μSv, while those for (40)K were from around 0.22 ± 0.04 to 1.2 ± 0.1 μSv. The overall intake of (137)Cs was low since low contamination was found in Boletus species.