title: Isotopic evidence of plutonium release into the environment from the Fukushima DNPP accident.
abstract: The Fukushima Daiichi nuclear power plant (DNPP) accident caused massive releases of radioactivity into the environment. The released highly volatile fission products, such as (129m)Te, (131)I, (134)Cs, (136)Cs and (137)Cs were found to be widely distributed in Fukushima and its adjacent prefectures in eastern Japan. However, the release of non-volatile actinides, in particular, Pu isotopes remains uncertain almost one year after the accident. Here we report the isotopic evidence for the release of Pu into the atmosphere and deposition on the ground in northwest and south of the Fukushima DNPP in the 20-30 km zones. The high activity ratio of (241)Pu/(239+240)Pu (> 100) from the Fukushima DNPP accident highlights the need for long-term (241)Pu dose assessment, and the ingrowth of (241)Am. The results are important for the estimation of reactor damage and have significant implication in the strategy of decontamination.
authors.forename: Jian
authors.initials: J
authors.lastname: Zheng
authors.forename: Keiko
authors.initials: K
authors.lastname: Tagami
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Watanabe
authors.forename: Shigeo
authors.initials: S
authors.lastname: Uchida
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Aono
authors.forename: Nobuyoshi
authors.initials: N
authors.lastname: Ishii
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yoshida
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Kubota
authors.forename: Shoichi
authors.initials: S
authors.lastname: Fuma
authors.forename: Sadao
authors.initials: S
authors.lastname: Ihara