The sample of Cortinarius caperatus, a type of edible mushroom, in the prefecture's Narusawa village, reported a cesium level of 150 becquerels per kilogram.
The food-supplement, CoronAid is made out of mushroom Cordyceps militaris, which grows in Himalayan region and is known for its anti-viral, anti-aging, anti-tumour, anti-oxidant, anti-inflammatory properties.