Here we go. And it's safe, I'm sure.
Yomiuri Shinbun (2:06AM JST 4/13/2011):
Ministry of Education and Science announced on April 12 that a minute amount of radioactive strontium has been found in the soils and weeds of 6 cities, towns and villages in Fukushima Prefecture including Iitate-mura, and Namie-machi.
Strontium-90 tends to accumulate in the bones as its chemical structure is similar to that of calcium. However, according to the Ministry, the amount detected this time was very minute and there is no ill-effect on humans. This is the first time that strontium was detected since the Fukushima I Nuke Plant accident started.
Iitate-mura had the highest level of strontium-90 at 32 becquerels per 1 kilogram of soil.
Yomiuri says "it's the first time that strontium was detected". Hmmm. It may be more like it's the first time that the Ministry thought about testing it.
Strontium-90 (Sr-90) is not easy to detect. You have to look for yttrium (Y) and deduce the amount of strontium, and it takes about a week to do the analysis and calculation.
Unlike volatile materials like iodine-131 and cesium-137, "heavier" elements like strontium and plutonium were not supposed to have spread to wider areas. Iitate-mura is about 39 kilometers (24 miles) northwest of Fukushima I Nuke Plant, on a pristine Abukuma Highlands. (Or "was pristine", sadly.)
I'm checking the Ministry of Ed and Science site for the actual numbers and locations..