These cattle were allowed to be sold, as long as they were scrubbed clean of radioactive materials on their skin, thanks to the Ministry of Agriculture, Forestry and Fisheries, the same ministry that is pushing to have the Japanese cuisine recognized as UNESCO's "world intangible cultural heritage".
According to Asahi Shinbun (link below), the Tokyo Metropolitan government tested the remaining 10 meat cows from Minami-Soma City that were processed on July 8. The highest number was 3200 becquerels/kg of cesium, and even the lowest number was 1530 becquerels/kg, more than 3 times the government's provisional safety limit for cesium in foods.
The one that was tested on July 8 had 2300 becquerels/kg radioactive cesium.
Asahi Shinbun (7/9/2011) also says:
Following the instruction from the Ministry of Agriculture, Forestry and Fisheries, the Metropolitan Shibaura Slaughterhouse doesn't conduct radiation testing at all, whether the cattle come from the 20-30 kilometer radius from Fukushima I Nuke Plant or from other areas. However, there have been 5 instances where the Ministry of Health, Labor and Welfare instructed them to test for radiation, and in those instances the radioactive materials detected were less than the provisional limit.
Yomiuri Shinbun (7/9/2011) says something more disturbing:
According to the investigation by Fukushima Prefecture, 2924 meat cows have been shipped from the same area since the end of April.
At the end of April, the Ministry of Agriculture, Forestry and Fisheries issued its guidance that would allow the shipment of meat cows from this area as long as Fukushima Prefecture conducted the radiation testing on the body surface of the cows and took other measures [i.e. questionnaires]. Accordingly, the shipment resumed which had been halted after the Fukushima I Nuke Plant accident.
I sort of know what will be coming shortly: a noise from the government's Nuclear Safety Commission that the current provisional safety limit is too strict, and there won't be anything that can be sold if the limit remains 500 becquerels/kg for cesium...
Many cows from Fukushima have been "evacuated" from Fukushima Prefecture, with only surface radiation testing and information on how they were raised, even to far-away places like Miyazaki Prefecture in Kyushu.
(For more details on how these cows - and pigs and chickens - moved out of Fukushima, thanks to the Ministry of Agriculture, Forestry and Fisheries, please read my new post.)