Health consequences of the Fukushima accident - Situation of workers involved in operations undertaken at the Fukushima Dai-ichi nuclear station. Situation update in February 2013

In a first part this report discusses the assessment of doses which have been potentially received by the Japanese population since the accident. It is based on results of radiological measurements performed on foodstuff with a land-based origin, and also dose assessments due to an exposure to the radioactive plume. It also discusses the potential levels of exposure of the Japanese population during different periods after the accident (during the first two weeks, during the next year, and after) due either to the radioactive plume or to radioactive fallouts on foodstuff. It outlines that received doses due to external exposure to deposits are now the main constraint in land management and in the recovery of evacuated areas. In a second part, the report describes the principles and objectives of epidemiological studies which have been implemented by Japanese health authorities after the Fukushima accident. These studies comprise a survey performed on the Prefecture inhabitants to asses the received external dose, to gather information on iodine tablet intake and foodstuff, water and beverage consumption, a thyroid function assessment on all children younger than 18, a follow-up of genetic or congenital anomalies, specific medical assessments on people evacuated from the most exposed areas. The report then discusses the progress and results of the current studies: results obtained with the questionnaire on received doses, results obtained on thyroid function for children exposed to radioactive releases, results obtained by the monitoring of evacuated people. The third part addresses the situation of workers involved in operations performed within the Fukushima nuclear station. It comments and discusses dose levels received by these workers according to data provided by Tepco, indicates some major effects noticed on workers (seven died but none due to exposure to ionizing radiations) and indicates how health monitoring is performed among workers. The last part describes the involvement of the IRSN in expert work groups set by the UNSCEAR