title: Global searches for microalgae and aquatic plants that can eliminate radioactive cesium, iodine and strontium from the radio-polluted aquatic environment: a bioremediation strategy.
abstract: The Fukushima 1 Nuclear Power Plant accident in March 2011 released an enormously high level of radionuclides into the environment, a total estimation of 6.3 × 10¹⁷ Bq represented by mainly radioactive Cs, Sr, and I. Because these radionuclides are biophilic, an urgent risk has arisen due to biological intake and subsequent food web contamination in the ecosystem. Thus, urgent elimination of radionuclides from the environment is necessary to prevent substantial radiopollution of organisms. In this study, we selected microalgae and aquatic plants that can efficiently eliminate these radionuclides from the environment. The ability of aquatic plants and algae was assessed by determining the elimination rate of radioactive Cs, Sr and I from culture medium and the accumulation capacity of radionuclides into single cells or whole bodies. Among 188 strains examined from microalgae, aquatic plants and unidentified algal species, we identified six, three and eight strains that can accumulate high levels of radioactive Cs, Sr and I from the medium, respectively. Notably, a novel eustigmatophycean unicellular algal strain, nak 9, showed the highest ability to eliminate radioactive Cs from the medium by cellular accumulation. Our results provide an important strategy for decreasing radiopollution in Fukushima area.
authors.affiliation: Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8572, Japan.
authors.forename: Shin-Ya
authors.initials: SY
authors.lastname: Fukuda
authors.forename: Koji
authors.initials: K
authors.lastname: Iwamoto
authors.forename: Mika
authors.initials: M
authors.lastname: Atsumi
authors.forename: Akiko
authors.initials: A
authors.lastname: Yokoyama
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nakayama
authors.forename: Ken-Ichiro
authors.initials: K
authors.lastname: Ishida
authors.forename: Isao
authors.initials: I
authors.lastname: Inouye
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Shiraiwa
mesh_terms: D001673:Biodegradation, Environmental; D002588:Cesium Radioisotopes / Q000032:analysis / Q000378:metabolism; D000458:Cyanobacteria / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D062406:Fukushima Nuclear Accident; D007457:Iodine Radioisotopes / Q000032:analysis / Q000378:metabolism; D007564:Japan; D055848:Nuclear Power Plants; D010802:Phylogeny; D011188:Potassium / Q000494:pharmacology; D000461:Rhodophyta / Q000187:drug effects / Q000378:metabolism*; D058009:Stramenopiles / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D013326:Strontium Radioisotopes / Q000032:analysis / Q000378:metabolism; D057948:Viridiplantae / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D014875:Water Pollutants, Radioactive / Q000032:analysis / Q000378:metabolism*
chemical_list: D002588:Cesium Radioisotopes; D007457:Iodine Radioisotopes; D013326:Strontium Radioisotopes; D014875:Water Pollutants, Radioactive; D011188:Potassium