The rice has been cleared for shipping, because the level of radioactive cesium is much below the national provisional safety limit of 500 becquerels/kg which will pose no threat to health, according to the authorities in Chiba.
It's "Koshihikari" brand rice, but since it's not from Niigata the rice may be blended and sold. If it's blended, there is no requirement to state where the rice was harvested.
Caveat emptor, except the buyers don't have all information available to them to decide on their own.
From Sankei Shinbun (8/27/2011):
Chiba Prefecture announced on August 27 that 46 becquerels/kg of radioactive cesium was detected from the rice harvested in Ichikawa City. The prefectural government considers the level as "not affecting health", and has permitted the shipment of the rice as of August 27.
In Chiba Prefecture, a small amount of radioactive cesium was detected in the rice before the harvest in Shirai City. The detection of radioactive cesium in rice in Ishikawa City is the second in Chiba, the fourth in Japan. One location in Hokota City in Ibaraki Prefecture and one location in Nihonmatsu City in Fukushima Prefecture also had radioactive cesium in rice.
According to Chiba Prefecture, radioactive cesium was detected from the brown rice of Koshihikari taken on August 24 in one location in Ichikawa City. No radioactive cesium was detected in rice in Chiba City, Noda City, Narita City, Choshi City and Asahi City.
Rice can be sold and shipped in 42 municipalities in Chiba Prefecture now that the post-harvest testing has been complete and the level of radioactive cesium was below the provisional safety limit.
That's what the provisional "safety" limit is there for: to plant the idea in people's mind that anything below that limit is "safe". Clearly many producers and all of government bureaucrats from municipal level upward believe that, and excoriate consumers who still don't buy that argument (and don't buy the produce).