ICP-MS determination of background I-129 in seaweed samples around Fukushima Daiichi NPS

Kim, Minseok
Shibata, Toshihiro
Sasaki, Takayuki
Suzuki, Junichi

¹Radiation and Environmental Department, Disaster Prevention and Radiation Center, Fukushima Daiichi D&D Engineering Company, Tokyo Electric Power Company Holdings, Inc., 22 Kitahara, Ottozawa, Okuma, Futaba-gun, Fukushima 979-1301, Japan
²Environmental Chemistry Department, Fukushima Nuclear Power Branch, Tokyo Power Technology, Ltd., 182-1 Nishikidai, Okuma, Futaba-gun, Fukushima 979-1305, Japan

^*Corresponding author. Radiation and Environmental Department, Disaster Prevention and Radiation Center, Fukushima Daiichi D&D Engineering Company, Tokyo Electric Power Company Holdings, Inc., 22 Kitahara, Ottozawa, Okuma, Futaba-gun, Fukushima 979-1301, Japan. Email: [email protected]

Received: October 26, 2023; Revised: June 16, 2024 Editorial decision: June 24, 2024; Accepted: July 1, 2024

Radiation Protection Dosimetry 200(16/18):p 1850-1855, November 2024. | DOI: 10.1093/rpd/ncae163

Abstract

TEPCO planned the release of Advanced Liquid Processing System (ALPS)-treated water, which is decontaminated stagnated water by ALPS, to the Pacific Ocean in 2023 after diluting it more than a hundred times in accordance with the policy of the Japan government. Since the low level of I-129 can remain in ALPS-treated water, the background I-129 concentration in seaweed samples around 1F NPS before the release of ALPS-treated water was recorded in this study. The iodine in seaweed samples was extracted via TMAH alkali-dissolution, and the I-129 concentration was measured by 8900 Triple Quadrupole ICP-MS. The resulting I-129 concentration was <5.4 × 10⁻² Bq/kg-wet (sargassum) and <2.7 × 10⁻² Bq/kg-wet (laminaria), respectively.