Abstract
137 Cs, 134 Cs and 40 K concentrations in 95 edible mushroom samples of 9 different species purchased in public food markets in Tokyo were analysed. 137 Cs concentrations were X2.23-37.1 Bq/kg in dried mushrooms (dried Lentinus edodes and Auricularia auricula), and <0.223-7.76 Bq/kg in raw mushrooms. 40 K were found in all mushroom samples but 134Cs was not detected. Annual intakes of 137Cs and40K (Bq⋅y-1⋅person-1) were estimated based on the statistics of mushroom consumption, which were then converted to internal dose equivalent using a dose conversion factor recommended by the ICRP Pub. 72. The average annual intake of 137 Cs was 4.33-5.01 Bq⋅y-1 'person-1 (arithmetic mean, lower limit being the value when "less than detectable level" was taken as "0" and upper limit when it was taken as "minimum detectable level") and 3.76 Bq ⋅y-1 ⋅person-1 (geometric mean) which corresponded to the dose equivalent of 5.6×10-5 -6.5×10-5 mSv ⋅y-1 and 4.8×10-5 mSv⋅⋅y-1 . The level was only 0.02-0.03 of the dose equivalent due to 40 K received by ordinary Japanese individual.
