Efficiency of Excess Monitoring for Beef after the Fukushima Accident

摘要

Herein we analyzed food monitoring data regarding the Fukushima accident. The Japanese government ordered local governments to implement food monitoring after the Fukushima nuclear accident. This protective action for food safety contributed to the reduction of internal radiation exposure derived from the Fukushima accident. According to the food monitoring data collected from March 2011 to March 2015, more than 70% of the samples were beef. One hundred fifty four samples from a total of 776,310 beef samples that were above provisional regulation values or new standard limits were restricted from market distribution. Most of the beef samples were below the detection limits by regulation of consumption of contaminated rice straw. Two hundred forty one from a total of 251,510 beef samples were above the detection limit during fiscal year 2014. The mean committed effective dose due to annual beef consumption was estimated to be 1 μSv. The 99.9 percentile committed effective dose was 20 μSv. Thus, internal exposure due to beef consumption is limited. However, local governments continue regular monitoring for beef in response to social concerns. It should be noted that continuous staff effort and high costs are required to maintain this food surveillance program. A formal evaluation may help to assist in the development of a more effective and efficient food monitoring system.