Deposition of Fukushima nuclear power plant accident-derived radiocesium in the soils of Jeju Island, Korea, and evidence for long- and short-lived radionuclides in rainwater. (February 2021) - Kang, Tae-Woo
Abstract: In this study, we investigated the concentrations of Fukushima nuclear power plant accident (FNPPA)-derived radiocesium ( 134 Cs, 137 Cs) deposited in the topsoil of Jeju Island, Korea. We also evaluated the soil inventories of radionuclides and compared the concentrations deposited by rainwater and fallout. We present the first evidence of FNPPA-derived radionuclides directly entering the environment of Jeju Island. In the case of FNPPA-derived 134 Cs in soil, only a trace amount was identified in the surface layer (1 cm depth), whereas 137 Cs derived from past atmospheric deposition of nuclear testing were detected along with those derived from the nuclear power plant accident. The total measured radiocesium ( 134 Cs + 137 Cs) indicates that although the value obtained from soils was slightly lower, both values were within the same order of magnitude. Of the FNPPA-derived radiocesium deposited in the soil, the impact from April 2011 was the largest at most sampling sites indicating that the radioactive plume directly covered Jeju Island. Furthermore, a variety of long- and short-lived gamma-emitting radionuclides were detected in the rainwater samples collected on April 7, 2011. Among them, short-lived radionuclides such as 140 La, 110m Ag, 95 Nb, 125 Sb, 113 Sn, 129 Te, 129m Te, 132 Te, 132 I, and 136 Cs, were observed. The findings of this study provide evidence for the direct effects of FNPPA-derived radionuclides in Jeju Island. This is the first location in Korea and the first in the entire East Asian region, excluding Japan that is confirmed to have been directly affected FNPP accident. Graphical abstract: Image 1 Highlights: Post-Fukushima soil and wet/dry deposition samples were collected from Jeju Island. Fukushima-derived radionuclides were detected in the collected samples. Total radiocesium inventories were affected by a plume that covered the Jeju Island. FNPPA-derived 134 Cs present in trace amounts in only the topsoil. . Short-lived radionuclides in rainwater indicate direct inflow from Fukushima.