Observation of Dispersion in the Japanese Coastal Area of Released 90Sr, 134Cs, and 137Cs from the Fukushima Daiichi Nuclear Power Plant to the Sea in 2013

Abstract

The March 2011 earthquake and tsunami resulted in significant damage to the Fukushima Daiichi Nuclear Power Plant (FDNPP) and the subsequent release of radionuclides into the ocean. Here, we investigated the spatial distribution of strontium-90 (90Sr) and cesium-134/cesium-137 (134, 137Cs) in surface seawater of the coastal region near the FDNPP. In the coastal region, 90Sr activity was high, from 0.89 to 29.13 mBq L−1, with detectable FDNPP site-derived 134Cs. This indicated that release of 90Sr from the power plant was ongoing even in May 2013, as was that of 134Cs and 137Cs. 90Sr activities measured at open ocean sites corresponded to background derived from atmospheric nuclear weapons testing fallout. The FDNPP site-derived 90Sr/137Cs activity ratios in seawater were much higher than those in the direct discharge event in March 2011, in river input, and in seabed sediment; those ratios showed large variability, ranging from 0.16 to 0.64 despite a short sampling period. This FDNPP site-derived 90Sr/137Cs activity ratio suggests that these radionuclides were mainly derived from stagnant water in the reactor and turbine buildings of the FDNPP, while a different source with a low 90Sr/137Cs ratio could contribute to and produce the temporal variability of the 90Sr/137Cs ratio in coastal water. We estimated the release rate of 90Sr from the power plant as 9.6 ± 6.1 GBq day−1 in May 2013 on the basis of the relationship between 90Sr and 137Cs activity (90Sr/137Cs = 0.66 ± 0.05) and 137Cs release rate.

Long-term variation of 90Sr and 137Cs in environmental and food samples around Qinshan nuclear power plant, China

“…Under natural environmental conditions, 137 Cs and 90 Sr mainly enter the human body through the food chain and respiration. Both 90 Sr and 137 Cs have long biological half-lives in the human body 3 – 8 , therefore it is important to continuously monitor 90 Sr and 137 Cs in environmental and food samples, especially those from the surroundings of nuclear facilities, to ensure the radiological safety of individuals and the environment. In contrast to 137 Cs, long-term monitoring data for 90 Sr activity in environmental and food samples worldwide are sparse.…”

Recent Development on Determination of Low-Level 90Sr in Environmental and Biological Samples: A Review

“…For large volume of environmental samples, evaporation is seldom used due to its time-consuming feature. 90 Sr in environmental water samples is usually coprecipitated with oxalates or carbonates, e.g., 90 Sr in natural waters can be co-precipitated with calcium oxalate under lower pH (pH = 4-5) which is thereafter decomposed into carbonate [2] or co-precipitated directly with calcium carbonate under higher pH (pH > 10).…”

“…1. Introduction 90 Sr (T½ = 28.79 y) is one of the most important hazardous radionuclides with respect to radiological safety to human and the environment due to its long half-life and high fission yield [1][2][3]. 90 Sr is a fission product of 235 U and 239 Pu; its decay chain is shown in Figure 1 [4].…”

Structural investigation of the efficient capture of Cs+ and Sr2+ by a microporous Cd–Sn–Se ion exchanger constructed from mono-lacunary supertetrahedral clusters

“…1,2 137 Cs and 90 Sr, with half lives of around 30 years, are two primary fission products from 235 U, and they can emit β or γ radiation and exhibit high levels of toxicity for human bodies, especially for people affected by nuclear accidents. 3,4 For example, the Fukushima nuclear leakage accident in 2011 resulted in the release of large quantities of 137 Cs + and 90 Sr 2+ ions into the surrounding environment. With a high migration ability, they are enriched in water, 5 soil, 6 forest vegetation 7 and other organisms.…”