Radioactivity impacts of the Fukushima Nuclear Accident on the atmosphere

The Fukushima Nuclear Accident (FNA) resulted in a large amount of radionuclides released into the atmosphere and dispersed globally, which has greatly raised public concerns. The state of the art for source terms of 19 kinds of radionuclides derived from the FNA was comprehensively collected and compared with levels of the global fallout and the Chernobyl Nuclear Accident (CNA). The atmospheric impacts of the FNA were evaluated from three aspects including radioactive baseline of the atmosphere, the concentration limits in standards and radiological protection. The FNA should not impose significant radiological risk on the public members in the countries excluding Japan. A conceptual scheme of Fukushima-derived radionuclides with physical and physicochemical insights on different temporal-spatial timescales was discussed and illustrated to understand their fates in the atmosphere.