Distribution of strontium-90 in soils affected by Fukushima dai-ichi nuclear power station accident in the context of cesium-137 contamination

Norbert Kavasi; Hideki Arae; Tatsuo Aono; Sarata Kumar Sahoo

doi:10.1016/j.envpol.2023.121487

Distribution of strontium-90 in soils affected by Fukushima dai-ichi nuclear power station accident in the context of cesium-137 contamination

Environ Pollut. 2023 Jun 1:326:121487. doi: 10.1016/j.envpol.2023.121487. Epub 2023 Mar 21.

Authors

Norbert Kavasi¹, Hideki Arae², Tatsuo Aono², Sarata Kumar Sahoo³

Affiliations

¹ Department of Radioecology and Fukushima Project, National Institute of Radiological Sciences, National Institutes for Quantum Sciences and Technology, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan; Laboratory for Radiochemistry, Department of Environmental Sciences, Jožef Stefan Institute, 39 Jamova, Ljubljana, 1000, Slovenia.
² Department of Radioecology and Fukushima Project, National Institute of Radiological Sciences, National Institutes for Quantum Sciences and Technology, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan.
³ Department of Radioecology and Fukushima Project, National Institute of Radiological Sciences, National Institutes for Quantum Sciences and Technology, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan. Electronic address: sahoo.sarata@qst.go.jp.

PMID: 36958665
DOI: 10.1016/j.envpol.2023.121487

Abstract

⁹⁰Sr and ¹³⁷Cs activity concentrations were determined by radiometric methods in 76 soil samples (soil, litter, rain gutter deposit, and roadside sediment samples) affected by the Fukushima Dai-ichi Nuclear Power Station (FDNPS) accident and collected from the Fukushima exclusion zone. The ⁹⁰Sr and ¹³⁷Cs activity concentrations were in the range of 3 to 1050 Bq kg^-1 (median 82 Bq·kg^-1) and 0.7 to 6770 kBq·kg^-1 (median 890 kBq·kg^-1), respectively (decay correction date: March 15, 2011). A strong positive correlation was found between ⁹⁰Sr and ¹³⁷Cs activity concentration and higher mobility of ⁹⁰Sr was confirmed in Japanese soil samples. The activity ratio of ⁹⁰Sr/¹³⁷Cs in 85% of all samples was in the range of 5.0 × 10^-5 to 5.0 × 10^-4 with a median of 1.2 × 10^-4. From the activity ratio values it was concluded that the ⁹⁰Sr released to the atmosphere was only around 0.0003-0.02 PBq which is negligible compared to the Chernobyl accident (∼10 PBq) or other nuclear accident contaminations. From the standpoints of radioecology and radiation safety, ¹³⁷Cs remains the primary pollutant of the FDNPS accident.

Keywords: Cesium-137; Fukushima; Nuclear accident; Soil; Strontium-90.

MeSH terms

Cesium Radioisotopes / analysis
Fukushima Nuclear Accident*
Japan
Radiation Monitoring* / methods
Soil
Soil Pollutants, Radioactive* / analysis

Substances

Soil
Cesium-137
Strontium-90
Cesium Radioisotopes
Soil Pollutants, Radioactive