Introduction

In the days following the earthquake and tsunami, which hit Eastern Japan on 11 March 2011, there was great uncertainly and concern about the extent of the radiation leakages emanating from the stricken nuclear power plant at Fukushima. To what extent have the radiation monitoring system and government announcements regarding radiation served to benefit public health? According to the Nuclear and Industrial Safety Agency, radioactive materials emitted into the air from 12 to 16 March 2011 were estimated at ¹³¹I 1.6×10¹⁷ Bq ¹³⁴Cs 1.8×10¹⁶ Bq and ¹³⁷Cs 1.5×10¹⁶ Bq.1 However, Stohl et al 2 reported that ¹³⁷Cs 3.58×10¹⁶ was emitted, more than twice the level announced by the Japanese government. They indicated the possibility of a radioactive material leakage from the unit 4 fuel pool and suggested that radioactive materials had already been emitted from the plant by the earthquake before the tsunami, which was inconsistent with government announcements. New concerns were raised over the safety of drinking water and farm products as radioactive contamination was spread over a wide area, which included Tokyo, by the rain that fell on 21–22 March. In this report, we will discuss the radiation monitoring system in Japan and make recommendations for the future.