Environmental behaviors of radionuclides

The presence of actinides in radioactive wastes is a major environmental concern. The accident of Fukushima Daiichi Nuclear Power Plant (FDNPP) caused release of radioactive materials into the atmosphere and subsequent dispersal. Several microorganisms have been shown to sorb actinides. In this paper, the author summarized our findings on the interactions of uranium and Pu, with microorganisms under aerobic condition. In addition, the author also summarized characteristics of the Cs microparticles containing not only radioactive Cs, but also U and other heavy elements. The items described are Association of actinides with microorganisms and clay, and Formation of radioactive cesium microparticles originating from FDNPP accident. (S.S.)