title: Absorption of radionuclides from the Fukushima nuclear accident by a novel algal strain.
abstract: Large quantities of radionuclides have leaked from the Fukushima Daiichi Nuclear Power Plant into the surrounding environment. Effective prevention of health hazards resulting from radiation exposure will require the development of efficient and economical methods for decontaminating radioactive wastewater and aquatic ecosystems. Here we describe the accumulation of water-soluble radionuclides released by nuclear reactors by a novel strain of alga. The newly discovered green microalgae, Parachlorella sp. binos (Binos) has a thick alginate-containing extracellular matrix and abundant chloroplasts. When this strain was cultured with radioiodine, a light-dependent uptake of radioiodine was observed. In dark conditions, radioiodine uptake was induced by addition of hydrogen superoxide. High-resolution secondary ion mass spectrometry (SIMS) showed a localization of accumulated iodine in the cytosol. This alga also exhibited highly efficient incorporation of the radioactive isotopes strontium and cesium in a light-independent manner. SIMS analysis showed that strontium was distributed in the extracellular matrix of Binos. Finally we also showed the ability of this strain to accumulate radioactive nuclides from water and soil samples collected from a heavily contaminated area in Fukushima. Our results demonstrate that Binos could be applied to the decontamination of iodine, strontium and cesium radioisotopes, which are most commonly encountered after nuclear reactor accidents.
authors.affiliation: Department of Environmental Medicine, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo, Yamanashi Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Shimura
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Itoh
authors.forename: Atsushi
authors.initials: A
authors.lastname: Sugiyama
authors.forename: Sayaka
authors.initials: S
authors.lastname: Ichijo
authors.forename: Masashi
authors.initials: M
authors.lastname: Ichijo
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Furuya
authors.forename: Yuji
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Ken
authors.initials: K
authors.lastname: Kitahara
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Yukawa
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Kobayashi
mesh_terms: D000042:Absorption; D001673:Biodegradation, Environmental; D002588:Cesium Radioisotopes / Q000302:isolation & purification; D062406:Fukushima Nuclear Accident; D007457:Iodine Radioisotopes / Q000302:isolation & purification; D058086:Microalgae / Q000302:isolation & purification / Q000378:metabolism* / Q000648:ultrastructure; D011868:Radioisotopes / Q000302:isolation & purification*; D012990:Soil Pollutants, Radioactive / Q000302:isolation & purification; D013326:Strontium Radioisotopes / Q000302:isolation & purification; D014875:Water Pollutants, Radioactive / Q000302:isolation & purification
chemical_list: D002588:Cesium Radioisotopes; D007457:Iodine Radioisotopes; D011868:Radioisotopes; D012990:Soil Pollutants, Radioactive; D013326:Strontium Radioisotopes; D014875:Water Pollutants, Radioactive