Concentrations of 137Cs and 40K in edible mushrooms collected in Japan and radiation dose due to their consumption.

Abstract

To estimate radiocesium intake due to eating mushrooms, about 100 samples belonging to 11 species were analyzed to establish representative values for 137Cs and 40K in common edible mushrooms available in food markets. Concentration ranges were <0.047-39 Bq kg(-1) (wet wt) for 137Cs and 30-210 Bq kg(-1) (wet wt) for 40K. The median concentrations were 1.3 Bq kg(-1) (wet wt) for 137Cs and 97 Bq kg(-1) (wet wt) for 40K. The 137Cs concentrations in cultivated mushrooms were markedly lower than those in wild mushrooms. The annual intake of 137Cs per person through mushrooms was calculated (using analytical results and food consumption data in Japan) to be 6.0 Bq for 137Cs, which is about 32% of the total dietary intake of this nuclide. The effective dose equivalent of 137Cs through mushroom was estimated to be 7.7 x 10(-8) Sv (range estimated from the standard deviation: 3.0 x 10(-8) - 2.0 x 10(-7)).