Radionuclides in mushrooms and soil-to-mushroom transfer factors in certain areas of China

Activity concentrations of 238U, 226Ra, 228Ra, 137Cs and 40K in 64 mushroom samples collected in China from Yunnan, Fujian and Heilongjiang Provinces, were measured. Gamma-ray emissions were determined by using high-purity germanium (HPGe) γ spectrometry. The range of concentrations (Bq kg−1 dry weight) for 238U, 226Ra, 228Ra, 137Cs and 40K in all investigated mushroom samples were from 0.12 to 12, 0.05 to 7.5, 0.14 to 14, MDC(<0.01) to 339, and 396 to 1880, respectively. Activity concentrations of 137Cs in mushrooms showed some variation between species sampled at the same site. To calculate soil to mushroom transfer factors, levels of radionuclide in 15 paired soil samples and mushrooms were also investigated. The median transfer factors for 238U, 226Ra, 228Ra, 137Cs and 40K were 8.32 × 10−2, 3.03 × 10−2, 6.69 × 10−2, 0.40 and 1.19, respectively. The results were compared with values of other areas.