The government does spot testing of cesium radiation in agricultural products against a standard that is much more lenient than anywhere else in the world (over triple the limits allowed in the Ukraine after the Chernobyl disaster) Beef exceeding those limits has been sold throughout much of Japan, partly because Fukushima cows have been shipped to other prefectures, and partly because radioactive feed from Fukushima has been shipped throughout the country and eaten by cows in other prefectures. And they aren't even testing for other forms of radiation such as strontium.

This level of radiation in food will have absolutely no short term impact on the consumer. It is debatable as to what sort of long term impact it could possibly have. But there is absolutely no doubt that the level of radiation in food in Japan is higher than other countries.

Unfortunately, I realize that this doesn't answer your question as to whether the food is safe. You will have to make that determination for yourself.