TY - JOUR
T1 - Dissolution of radioactive, cesium-rich microparticles released from the Fukushima Daiichi Nuclear Power Plant in simulated lung fluid, pure-water, and seawater
AU - Suetake, Mizuki
AU - Nakano, Yuriko
AU - Furuki, Genki
AU - Ikehara, Ryohei
AU - Komiya, Tatsuki
AU - Kurihara, Eitaro
AU - Morooka, Kazuya
AU - Yamasaki, Shinya
AU - Ohnuki, Toshihiko
AU - Horie, Kenji
AU - Takehara, Mami
AU - Law, Gareth T.W.
AU - Bower, William
AU - Grambow, Bernd
AU - Ewing, Rodney C.
AU - Utsunomiya, Satoshi
N1 - Funding Information:
The authors are grateful to Dr. Watanabe for her assistance on SEM analyses at the Center of Advanced Instrumental Analysis, Kyushu University. This study is partially supported by JST Initiatives for Atomic Energy Basic and Generic Strategic Research and by a Grant-in-Aid for Scientific Research ( KAKENHI ) from the Japan Society for the Promotion of Science ( 16K12585 , 16H04634 , No. JP26257402 ). S.U. is also supported by the Mitsubishi Foundation/Research Grants in the Natural Sciences and by ESPEC Foundation for Global Environment Research and Technology (Charitable Trust) (ESPEC Prize for the Encouragement of Environmental Studies). The findings and conclusions of the authors of this paper do not necessarily state or reflect those of the JST.
PY - 2019/10
Y1 - 2019/10
N2 - To understand the chemical durability of highly radioactive cesium-rich microparticles (CsMPs) released from the Fukushima Daiichi Nuclear Power Plant in March 2011, we have, for the first time, performed systematic dissolution experiments with CsMPs isolated from Fukushima soils (one sample with 108 Bq and one sample with 57.8 Bq of 137Cs) using three types of solutions: simulated lung fluid, ultrapure water, and artificial sea water, at 25 and 37 °C for 1–63 days. The 137Cs was released rapidly within three days and then steady-state dissolution was achieved for each solution type. The steady-state 137Cs release rate at 25 °C was determined to be 4.7 × 103, 1.3 × 103, and 1. 3 × 103 Bq·m−2 s−1 for simulated lung fluid, ultrapure water, and artificial sea water, respectively. This indicates that the simulated lung fluid promotes the dissolution of CsMPs. The dissolution of CsMPs is similar to that of Si-based glass and is affected by the surface moisture conditions. In addition, the Cs release from the CsMPs is constrained by the rate-limiting dissolution of silicate matrix. Based on our results, CsMPs with ∼2 Bq, which can be potentially inhaled and deposited in the alveolar region, are completely dissolved after >35 years. Further, CsMPs could remain in the environment for several decades; as such, CsMPs are important factors contributing to the long-term impacts of radioactive Cs in the environment.
AB - To understand the chemical durability of highly radioactive cesium-rich microparticles (CsMPs) released from the Fukushima Daiichi Nuclear Power Plant in March 2011, we have, for the first time, performed systematic dissolution experiments with CsMPs isolated from Fukushima soils (one sample with 108 Bq and one sample with 57.8 Bq of 137Cs) using three types of solutions: simulated lung fluid, ultrapure water, and artificial sea water, at 25 and 37 °C for 1–63 days. The 137Cs was released rapidly within three days and then steady-state dissolution was achieved for each solution type. The steady-state 137Cs release rate at 25 °C was determined to be 4.7 × 103, 1.3 × 103, and 1. 3 × 103 Bq·m−2 s−1 for simulated lung fluid, ultrapure water, and artificial sea water, respectively. This indicates that the simulated lung fluid promotes the dissolution of CsMPs. The dissolution of CsMPs is similar to that of Si-based glass and is affected by the surface moisture conditions. In addition, the Cs release from the CsMPs is constrained by the rate-limiting dissolution of silicate matrix. Based on our results, CsMPs with ∼2 Bq, which can be potentially inhaled and deposited in the alveolar region, are completely dissolved after >35 years. Further, CsMPs could remain in the environment for several decades; as such, CsMPs are important factors contributing to the long-term impacts of radioactive Cs in the environment.
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U2 - 10.1016/j.chemosphere.2019.05.248
DO - 10.1016/j.chemosphere.2019.05.248
M3 - Article
C2 - 31195267
AN - SCOPUS:85066925414
VL - 233
SP - 633
EP - 644
JO - Chemosphere
JF - Chemosphere
SN - 0045-6535
ER -