– Radioactive Cesium from Shiitake Mushrooms Grown Indoors in Date City, Fukushima (Ex-SKF, July 15, 2011):
(Update: 28 kg of Date City shiitake were sold within Fukushima. 129 kg of Motomiya City shiitake went to the fresh produce wholesale market in Tokyo, according to Asahi.)
1,770 becquerels per kilogram. That’s the first since the government started the sample testing of food items. Date City is more than 50 kilometers northwest of Fukushima I Nuclear Power Plant.
From Yomiuri Shinbun (10:08AM JST 7/16/2011):
厚 生労働省は１５日、福島県伊達市の施設栽培シイタケで暫定規制値（１キロ当たり５００ベクレル）を上回る同１７７０ベクレルの放射性セシウムが検出され たと発表した。 本宮市でも５６０ベクレルを検出した。露地栽培シイタケではすでに同県内の１６市町村で出荷が制限されているが、施設栽培シイタケで規制 値を上回ったのは初めて。政府は出荷制限を検討する。
The Ministry of Health, Labor and Welfare announced on July 15 that 1,770 becquerels/kg of radioactive cesium was detected from shiitake mushrooms grown indoors in Date City, Fukushima Prefecture. The provisional safety limit is 500 becquerels/kg. Shiitake mushrooms grown in Motomiya City in Fukushima also tested 560 becquerels/kg of radioactive cesium. Already, 16 municipalities in Fukushima Prefecture restrict the shipment of shiitake mushrooms grown outdoors. This is the first time that shiitake mushrooms that were grown indoors tested above the safety limit. The national government will consider the shipment restriction.
Where did this cesium come from, if the mushrooms were grown indoors? Is the indoor air just as contaminated as the outdoor air in Date City? Or was it the mushroom substrate blocks (for indoor cultivation) that were contaminated?