Abstract
This paper reports the results of environmental studies conducted in May‒June 2021 in 16 prefectures of Japan, over which radioactive clouds spread as a result of the accident at the Fukushima-1 nuclear power plant in March 2011, namely: Aomori, Miyagi, Fukushima, Niigata, Ishikawa, Ibaraki, Kanagawa, Shizuoka, Osaka, Kyoto, Okayama, Tottore, Shimane, Kagoshima, Nagasaki, and Ehime. Some effects of the impact of accidental emissions of BWR-3 and BWR-4 reactors on the environment in the settlements neighboring the Fukushima-1 nuclear power plant were summed up. The methods of conducting research are described, starting with a sampling of environmental objects in the above prefectures (atmospheric air, soil, vegetation, agricultural products, sea and ocean water, and aquatic fauna) and sample preparation up to measurements and data processing to obtain results and their subsequent analysis. A comparison of the results of research with the volumes of emissions of radioactive substances due to the normal operation of various objects for the use of atomic energy was carried out. Conclusions are drawn about the medium-term (after 10 years) consequences of the nuclear accident at the Fukushima-1 nuclear power plant. The maximum background radiation equal to 2 µmSv/h observed at point No. 83, 20 km from the Fukushima-1 nuclear power plant, will not lead to irradiation of a person with doses exceeding the permissible limits if the time of his stay at the reference point is limited to 1.36 hours per day. The concentration of cesium-137 in the water of Japanese waters does not exceed the level of the radiation factor, upon reaching which protective intervention is necessary. The maximum specific activity of cesium-137, detected in soil and vegetation samples near the Fukushima-1 nuclear power plant, does not exceed the maximum specific activity (MZUA). In Japan as a whole, the specific activity of radionuclides in soils used for agricultural production and livestock grazing does not exceed the levels of global pollution.
Highlights
The accident at the Fukushima-1 nuclear power plant was assigned a level 7 of complexity on the INES scale [1] ‒ the same as that of the Chernobyl accident, the amount of radioactivity released into the environment as a result of the accident at the Fukushima-1 nuclear power plant (770∙1015 Bq) is no more than 15 % of the emissions from the Chernobyl accident (5200×1015 Bq)
Permissible values of radioactive contamination do not exceed the residual level in precipitation and settling dust, sea and ocean water, soil, vegetation, and agricultural products, samples of which were taken in the same prefectures of Japan where gamma background and air intake levels were measured
The highest volumetric activity of atmospheric air (4.3×10–3 Bq/m3) and the level of surface pollution by dust and precipitation (1.5×10–6 Bq/km2), containing mainly cesium-137, are registered in Fukushima Prefecture, when conducting individual dosimetry control of Japanese residents, it is necessary to take into consideration internal irradiation with traces of cesium present in the atmospheric air and settling dust after the accident at the Fukushima-1 nuclear power plant
Summary
The accident at the Fukushima-1 nuclear power plant was assigned a level 7 of complexity on the INES scale [1] ‒ the same as that of the Chernobyl accident, the amount of radioactivity released into the environment as a result of the accident at the Fukushima-1 nuclear power plant (770∙1015 Bq) is no more than 15 % of the emissions from the Chernobyl accident (5200×1015 Bq). Comparison of the consequences of nuclear accidents by the total activity of volley ejection is not fully justified from the point of view of physics since the summation of the activities of alpha-, beta-, gamma- and neutron emitters is illogical, but, it is the only way to make a quantitative comparison of the scale of the incidents. Studies on radiation monitoring in the area of the Fukushima-1 nuclear power plant 10 years after the accident are relevant, in order to determine the gamma radiation background of the area in the prefectures over which the plumes of radioactive clouds spread, as well as residual levels of radioactive contamination of environmental objects and agricultural products
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
