(UPDATE-2) Asahi Shinbun carried the news:
(UPDATE) So far, it is dead silence from the Japanese MSMs; even the critical papers like Tokyo Shinbun is mum on strontium in Tokyo.
A citizen group did the soil survey of three locations in central Tokyo, and had the soil samples tested for radioactive cesium and strontium. All three had both.
Summary of reporting by Yasumi Iwakami, independent journalist:
Locations and amounts of radioactive materials:
Kiyosumi Shirakawa Station, Koto-ku:
Radioactive cesium (134 and 137 combined): 19,126 Bq/kg
Radioactive strontium (89 and 90 combined): 44 Bq/kg
Yurakucho Station, Chiyoda-ku:
Radioactive cesium (134 and 137 combined): 20,955 Bq/kg
Radioactive strontium (89 and 90 combined): 51 Bq/kg
Front of the Ministry of Economy, Trade and Industry, Chiyoda-ku:
Radioactive cesium (134 and 137 combined): 48,176 Bq/kg
Radioactive strontium (89 and 90 combined): 48 Bq/kg
It's a poetic justice that the amount of radioactive cesium is the highest at METI. I hear TEPCO's headquarter building in Tokyo also enjoys rather high radiation.
Iwakami cautions that radioactive strontium may be confirmed to have come from Fukushima only after the detailed analysis at a laboratory that can separately measure strontium-89 and strontium-90. The presence of cesium-134 seems to prove that at least radioactive cesium found in the soil samples is of Fukushima origin.
I believe there is only one or two laboratories in Japan that does that; one of them is the laboratory that TEPCO uses for the radionuclide analysis (Japan Chemical Analysis Center).
It looks like the national government may make a comment or two on this discovery later, some people are hoping that the government does. What would the government say? Let me guess... How about "No immediate effect on health", and "We should only worry about cesium, forget the rest".
By the way, you may recall the discovery of radioactive strontium on the rooftop of an apartment building in Kohoku-ku in Yokohama City in October. There has been no response from the city to the citizen who measured it, and no action from the city whatsoever on removing the highly radioactive sediment from the rooftop or decontaminating.