Strontium-90 activity concentration in soil samples from the exclusion zone of the Fukushima daiichi nuclear power plant

Abstract

The radioactive fission product 90Sr has a long biological half-life (˜18 y) in the human body. Due to its chemical similarity to calcium it accumulates in bones and irradiates the bone marrow, causing its high radio-toxicity. Assessing 90Sr is therefore extremely important in case of a nuclear disaster. In this work 16 soil samples were collected from the exclusion zone (<30 km) of the earthquake-damaged Fukushima Daiichi nuclear power plant, to measure 90Sr activity concentration using liquid scintillation counting. 137Cs activity concentration was also measured with gamma-spectroscopy in order to investigate correlation with 90Sr. The 90Sr activity concentrations ranged from 3.0 ± 0.3 to 23.3 ± 1.5 Bq kg−1 while the 137Cs from 0.7 ± 0.1 to 110.8 ± 0.3 kBq kg−1. The fact that radioactive contamination originated from the Fukushima nuclear accident was obvious due to the presence of 134Cs. However, 90Sr contamination was not confirmed in all samples although detectable amounts of 90Sr can be expected in Japanese soils, as a background, stemming from global fallout due to the atmospheric nuclear weapon tests. Correlation analysis between 90Sr and 137Cs activity concentrations provides a potentially powerful tool to discriminate background 90Sr level from its Fukushima contribution.

Adsorption of strontium and caesium onto an Na-MX80 bentonite: Experiments and building of a coherent thermodynamic modelling

“…90 Sr and 137 Cs, with half-lives of 29 and 30 years, respectively, are amongst the major by-products from the fission of 235 U (England and Rider, 1993). These isotopes were spread in the environment after the fall-out of the different nuclear weapon detonations, and after the nuclear accidents at Chernobyl (IAEA, 2006) and Fukushima-Daiichi (Sahoo et al, 2016). Because of its capacity to substitute with calcium in the food chain, 90 Sr can disturb ecological systems (Comar et al, 1957).…”

Incorporation and Accumulation of Strontium-90 in the Hard Tissue of Animals and Their Relationship with Strontium-90 Pollution in the Environment

“…It was reported that 90 Sr activity concentration in soil and vegetation samples is one to four orders of magnitude lower than that of 137 Cs [12]. Sahoo et al showed that 90 Sr activity concentration in soil from the ex-evacuation zone of the FNPP accident ranged from 3 to 23 Bq/kg, whereas 137 Cs activity concentration ranged from 0.7 to 110 kBq/kg [13], which is consistent with the previous reports [3,10]. The ratio of 90 Sr/ 137 Cs in soil widely varies depending on the area examined.…”

Hybrid Nanoparticle–Polymer Brush Composites for Detection of Low‐Level Radiostrontium in Water

“…Strontium‐90 together with 137 Cs are major long‐lived radionuclides in spent nuclear fuel and high‐level radioactive wastes . Strontium‐90 is present in surface soil around the world mainly as a result of fallout from past atmospheric nuclear weapons tests, as well as nuclear plant accidents . Moreover, strontium as an element is relatively mobile and can move down with percolating water to underlying layers of soil and into groundwater .…”