Radioactive material in sludge at 16 prefectures, NHK, June 14, 2011:
[...] NHK has found through interviews that at least 22 of Japan’s 47 prefectures have been testing sludge for radioactive material. 16 of them, ranging from Hokkaido to Osaka, have actually detected radioactive substances.
The level of radioactive cesium was highest in Fukushima city, at 447,000 becquerels per kilogram. This was followed by Tokyo at 55,000 becquerels and Maebashi, north of Tokyo, at 42,800 becquerels.
Published: June 14th, 2011 at 9:48 am ET