FUKUSHIMA FALLOUT IN SAKHALIN REGION, RUSSIA, PART 1: 137CS AND 134CS IN GRASSLAND SOILS

The  caesium-134  and  caesium-137  radionuclides released into the atmosphere as a  result of the Fukushima accident were dispersed over the entire Northern Hemisphere. To assess the risks associated with the exposure due to Fukushima fallout, a comprehensive radiological survey was performed in the Russian Far East. One of the objectives of the project was to determine the densities of ground contamination by ¹³⁷Cs and ¹³⁴Cs on Sakhalin and Kuril Islands that constitute the Sakhalin oblast, an administrative region of Russia. In 2011, soil samples were collected at grasslands on Sakhalin, Kunashir and Shikotan Islands and results of the 2011 survey were published earlier. In the present study, activities of ¹³⁷Cs and ¹³⁴Cs were measured in soil samples obtained on Kunashir, Iturup, Urup and Paramushir Islands in 2012. From the studies carried out in 2011–2012,  it was estimated that the Fukushima-derived ¹³⁴Cs inventory at 37 undisturbed grassland sites in the Sakhalin oblast varied from 8 Bq m⁻² to 345 Bq m⁻² (as of 15 March 2011). For this date, the inventory of the ¹³⁷Cs radionuclide originated from the Fukushima NPP was assumed to be the same as that of the ¹³⁴Cs radionuclide. The southern Kuril Islands were the most contaminated due to Fukushima fallout. In 2011 and 2012, Fukushima-derived radiocaesium was detected only in the top 5 cm layer of soil at all sites, excluding one, where ~20% of the ¹³⁴Cs inventory was found at a depth of 5–10  cm. In the period September 2011– September 2012, the inventory of ¹³⁴Cs declined by ~26% at four plots selected for long-term observations. The decline in the ¹³⁴Cs inventory closely corresponded to the reduction (29%) of ¹³⁴Cs activity due to radioactive decay. Pre-accidental inventory of ¹³⁷Cs in the top 20 cm layer of soil ranged from 53 Bq m−2 to 3630 Bq m⁻². The mean reference inventory of pre-accidental ¹³⁷Cs for 13 representative sites was amounted as 2600 Bq m⁻². Hence, the Fukushima accident added relatively small quantities of radioactivity to the reference preaccidental inventory of ¹³⁷Cs in grassland soils in the Sakhalin region: about 3% (~80 Bq m⁻²) on the average and 15% (~350 Bq m⁻²) at the maximum. Such small additional radioactive contamination is absolutely safe from a radiological point of view.

1. UNSCEAR – United Nations Scientific Committee on the Effects of Atomic Radiation, 2014. UNSCEAR 2013 Report. Annex A: Levels and Effects of Radiation Exposure Due to the Nuclear Accident After the 2011 Great East-Japan Earthquake and Tsunami. United Nations, New York.

2. IAEA – International Atomic Energy Agency, 2015. The Fukushima Daiichi Accident. Technical volume 4/5. Radiological consequences. IAEA, Vienna.

3. Thakur, P., Ballard, S., Nelson, R., 2013. An overview of Fukushima radionuclides measured in the northern hemisphere. Sci. Tot. Environ., Vol. 458–460, pp. 577–613.

4. Onischenko, G.G., Romanovich, I.K., Balonov, M.I., Barkovsky, A.N., Gorsky, A.A., 2011. Accident at «Fukushima-1» NPP: first results of emergency response. Report 1: general information about the accident and radiation situation. Radiatsionnaya Gygiena = Radiation Hygiene, Vol. 4, No. 2, pp. 5–12. – Available on: http://www.radhyg.ru/jour/article/view/186/203> (accessed 11 February 2018) (In Russian).

5. Romanovich, I.K., Balonov, M.I., Barkovsky, A.N., Nikitin, A.I., et al.; Ed.: G.G. Onischenko, 2012. The Accident at the “Fukushima-1” NPP: Prophylactic Countermeasures for Health Safety of the Population of the Russian Federation. Federal Scientific Organization «Saint-Petersburg Research Institute of Radiation Hygiene after professor P.V. Ramzaev», Saint-Petersburg, 336 pp. (In Russian).

6. Saito, K., Tanihata, I., Fujiwara, M., Saito, T., Shimoura, S., Otsuka, T., Onda, Y., Hoshi, H., Ikeuchi, Y., Takahashi, F., Kinouchi, N., Saegusa, J., Seki, A., Takemiya, H., Shibata, T., 2015. Detailed deposition density maps constructed by large-scale soil sampling for gamma-ray emitting radioactive nuclides from the Fukushima Dai-ichi Nuclear Power Plant accident. J. Environ. Radioact., Vol. 139, pp. 308–319.

7. Hasegawa, A., Ohira, T., Maeda, M., Yasumura, S., Tanigawa, K., 2016. Emergency responses and health consequences after the Fukushima accident; evacuation and relocation. Clinical Oncology, Vol. 28, pp. 237–244.

8. Fukushima Prefecture, 2018. Decontamination in the prefecture. – Available on: https://www.pref.fukushima.lg.jp/site/portal-english/en02-03.html > (accessed 12 February 2018).

9. Marzo, G., 2014. Atmospheric transport and deposition of radionuclides released after the Fukushima Dai-chi accident and resulting effective dose. Atmos. Environ., Vol. 94, pp. 709–722.

10. Onischenko, G.G., Romanovich, I.K., Barkovsky, A.N., Bruk, G.Ya., Gorsky, А.А., Kaduka, M.V., Konstantinov, Yu.O., Mishin, A.S., Ramzaev, V.P., Repin, V.S., Shutov, V.N., Gromov, A.V., Goncharova, Yu.N., Yakovlev, V.A., 2011. Accident at «Fukushima-I» NPP: first results of emergency response. Report 2: activities of the Rospotrebnadzor authorities for the radiation protection of the Russian Federation population on the early stage of accident. Radiatsionnaya Gygiena = Radiation Hygiene, Vol. 4, No. 2, pp. 13–22. – Available on: http://www.radhyg.ru/jour/article/view/187/204 > (accessed 11 February 2018) (In Russian).

11. Christoudias, T., Proestos, Y., Lelieveld, J., 2014. Global risk from the atmospheric dispersion of radionuclides by nuclear power plant accidents in the coming decades. Atmos. Chem. Phys., Vol. 14, pp. 4607–4616.

12. Molchanova, I.V., Mikhailovskaya, L.N., Pozolotina, V.N., Zhuravlev, Y.N., Timofeeva, Y.O., Burdukovskii, M.L., 2013. Technogenic pollution of soil and plant cover in southern Primorye. Russ. J. Ecol., Vol. 44, pp. 371–374.

13. Mikhailovskaya, L.N., Molchanova, I.V., Pozolotina, V.N., Zhuravlev, Yu.N., Timofeeva, Ya.O., Burdukovsky, M.L., 2017. Radioactive contamination of the soil–plant cover at certain locations of Primorsky Krai, Sakhalin Island and Kamchatka Peninsula: Assessment of the Fukushima fallout. J. Environ. Radioact., Vol. 172, pp. 1–9.

14. McKenzie, T, Dulai, H., 2017. Fukushima-derived radiocesium fallout in Hawaiian soils. J. Environ. Radioact., Vol. 180, pp. 106–113.

15. Borisov, A.P., Ivanov, А.N., Linnik, V.G., Solovyeva, G.Yu., 2017. Determination of Pb-210 and Cs-137 data of gamma-spectrometry in the surface layer of the soil of Matua Island (Central Kuriles). Proceedings of Russian Annual Seminar on Experimental Mineralogy, Petrology and Geochemistry (RASEMPG – 2017), Moscow, 18–19 April 2017, Moscow, 286–289 pp. – Available on: https://www.researchgate.net/publication/321028148 > (accessed 11 February 2018) (In Russian).

16. Ramzaev, V., Barkovsky, A., Goncharova, Ya., Gromov, A., Kaduka, M., Romanovich, I., 2013. Radiocesium fallout at the grasslands on Sakhalin, Kunashir and Shikotan Islands due to the Fukushima accident: the radioactive contamination of soil and plants in 2011. J. Environ. Radioact., Vol. 118, pp. 128–142.

17. Klimov, O., 2013. Background knowledge. Vokrug Sveta, No. 3, pp. 87–93. – Available on: http://www.vokrugsveta.ru/vs/article/8064/ > (accessed 11 March 2018) (In Russian).

18. Ganzey, K.S., 2010. Landscapes and Physico-Geographical Zonation of Kuril Islands. Dalnauka, Vladivostok, 214 pp. (In Russian).

19. Razzhigaeva, N.G., Ganzey, L.A., Mokhova, L.M., Pshenichnikova, N.F., 2011. Meadow landscapes of Southern Kuriles: origin, age and development. Geography and Natural Resources, No. 3, pp. 96–104. – Available on: http://www.izdatgeo.ru/pdf/gipr/2011-3/96.pdf > (accessed 11 February 2018) (In Russian).

20. Razzhigaeva, N.G., Ganzey, L.A., Mokhova, L.M., Pshenichnikova, N.F., Eremenko, N.A., 2008. The origin and age of grasslands in the southern Kuril Islands. In: H.G. Schroder (Ed.), Grasslands: Ecology, Management and Restoration. Nova Science Publishers, Inc., pp. 205–234. – Available on: https://www.researchgate.net/publication/288724556 > (accessed 11 February 2018).

21. Grishin, S.Yu., Shlakhov, S.A., 2008. Vegetation and soils of Paramushir Island (the northern Kurile). Geography and Natural Resources, No. 4, pp. 96–103. (In Russian).

22. Polokhin, O.V., Sibirina, L.A., 2014. Soil and vegetation cover of the island of Iturup (Kuril Islands). Modern Problems of Science and Education, No. 5. Available on: https://www.science-education.ru/ru/article/view?id=15179 > (accessed 11 February 2018) (In Russian).

23. Gusiakov, V.K., 2016. Tsunamis on the Russian Pacific coast: history and current situation. Russian Geology and Geophysics, Vol. 57, No. 9, pp. 1259–1268. (In Russian).

24. Kravchunovskaya, E.A., Pinegina, T.K., Bourgeois, J., MacInnes, B.T., 2008. Geology-geomorphological effects of the 15.11.2006 tsunami in the Central Kuril. In: Geophysical monitoring and problems of seismic safety in the Far East of Russia: in 2 volumes. Proceedings of the Regional Scientific and Technical Conference, Petropavlovsk-Kamchatsky, November 11–17, 2007. Petropavlovsk-Kamchatsky: GS RAS., Vol. 1, pp. 180–183. Available on: http://www.emsd.ru/konf071112/pdf/t1/str180.pdf > (accessed 11 February 2018) (In Russian).

25. Ramzaev, V., Repin, V., Medvedev, A., Khramtsov, E., Timofeeva, M., Yakovlev, V., 2012. Radiological investigations at the “Taiga” nuclear explosion site, part II: man-made γ-ray emitting radionuclides in the ground and the resultant kerma rate in air. J. Environ. Radioact., Vol. 109, pp. 1–12.

26. Strom, D.J., Stransbury, P.S., 1992. Minimum detectable activity when background is counted longer than the sample. Health Phys., Vol. 63, pp. 360–361.

27. Ramzaev, V.P., Barkovsky, A.N., Gromov, A.V., Ivanov, S.A., Kaduka, M.V., 2016. Temporal variations of 7Be, 40K, 134Cs and 137Cs in epiphytic lichens (genus Usnea) at the Sakhalin and Kunashir islands after the Fukushima accident. Radiatsionnaya Gygiena = Radiation Hygiene, Vol. 9, No. 3, pp. 14–27. Available on: http://www.radhyg.ru/jour/article/view/376 > (accessed 11 February 2018).

28. ICRP – International Commission on Radiological Protection, 1983. Radionuclide Transformations. Energy and Intensity of Emissions. ICRP Publication 38. Pergamon Press, Oxford, Frankfurt.

29. Arapis, G., Petrayev, E., Shagalova, E., Zhukova, O., Sokolik, G., Ivanova, T., 1997. Effective migration velocity of 137Cs and 90Sr as a function of the type of soils in Belarus. J. Environ. Radioact., Vol. 34, pp. 171–185.

30. Ramzaev, V., Barkovsky, A., 2018. Vertical distribution of 137Cs in grassland soils disturbed by moles (Talpa europaea L.). J. Environ. Radioact., Vol. 184–185, pp. 101–108.

31. Hirose, K., 2012. 2011 Fukushima Dai-ichi nuclear power plant accident: summary of regional radioactive deposition monitoring results. J. Environ. Radioact., Vol. 111, pp. 13–17.

32. Ramzaev, V., Barkovsky, A., Gromov, A., Ivanov, S., Kaduka, M., 2014. Epiphytic fruticose lichens as biomonitors for retrospective evaluation of the 134Cs/137Cs ratio in Fukushima fallout. J. Environ. Radioact., Vol. 138, pp. 177–185.

33. Mann, H.B., Whitney, D.R., 1947. On a test of whether one of two random variables is stochastically larger than the other. Ann. Math. Stat., Vol. 18, No. 1, pp. 50–60.

34. Dixon, W.J., Mood, A.M., 1946. The statistical sign test. J. Am. Stat. Ass., Vol. 41, No. 236, pp. 557–566.

35. Spearman, C., 2010. The proof and measurement of association between two things. Int. J. Epidemiol., Vol. 39, pp. 1137–1150. Reprinted with permission from: Am. J. Psychol., 1904, Vol. 15, pp. 72–101.

36. UNSCEAR – United Nations Scientific Committee on the Effects of Atomic Radiation, 2000. Sources and Effects of Ionizing Radiation, Report to the General Assembly with Scientific Annexes. United Nations, New York.

37. Schimmack, W., Steindl, H., Bunzl, K., 1998. Variability of water content and of depth profiles of global fallout 137Cs in grassland soils and the resulting external gamma-dose rates. Radiat. Environ. Biophys., Vol. 37, pp. 27–33.

38. Huh, C.-A., Su, C.-C., 2004. Distribution of fallout radionuclides (7Be, 137Cs, 210Pb and 239,240Pu) in soils of Taiwan. J. Environ. Radioact., Vol. 77, pp. 87–100.

39. Almgren, S., Isaksson, M., 2006. Vertical migration studies of 137Cs from nuclear weapons fallout and the Chernobyl accident. J. Environ. Radioact., Vol. 91, pp. 90–102.

40. Christoudias, T., Lelieveld, J., 2013. Modelling the global atmospheric transport and deposition of radionuclides from the Fukushima Dai-ichi nuclear accident. Atmos. Chem. Phys. Vol. 13, pp. 1425–1438.

41. Izrael, Yu.A., Imshennik, E.V., Kvasnikova, E.V., Nazarov, I.M., Stukin, E.D., 2000. Radioactive contamination of Russia by global fallout from nuclear tests and by Chernobyl deposition. Map on the 90th of XX century. In: Izrael, Yu.A. (Ed.), Radioactivity after Nuclear Explosions and Accidents. Proceedings of International Conference. Moscow, 24–26 April 2000, Vol. 1. Hydrometeoizdat, St. Petersburg, pp.138–145. (In Russian).

42. Schuller, P., Voigt, G., Handl, J., Ellies, A., Oliva, L., 2002. Global weapons’ fallout 137Cs in soils and transfer to vegetation in south-central Chile. J. Environ. Radioact., Vol. 62, pp. 181–193.

43. MacInnes, B.T., Bourgeois, J., Pinegina, T.K., Kravchunovskaya, E.A., 2009. Tsunami geomorphology: Erosion and deposition from the 15 November 2006 Kuril Island tsunami. Geology, Vol. 37, pp. 995–998.

44. Bruk, G.Ya., Romanovich, I.K., Bazyukin, A.B, Bratilova, A.A., Vlasov, A.Yu., Gromov, A.V., Zhesko, T.V., Kaduka, M.V., Kravtsova, O.S., Saprykin, K.A., Stepanov, V.S., Titov, N.V., Yakovlev, V.A., 2017. The average annual effective doses for the population in the settlements of the Russian Federation attributed to zones of radioactive contamination due to the Chernobyl accident (for the zonation purposes), 2017. Radiatsionnaya Gygiena = Radiation Hygiene, Vol. 10, No. 4, pp.73–78. – Available on: http://www.radhyg.ru/jour/article/view/530/536 > (accessed 11 February 2018) (In Russian).

45. Ramzaev, P.V., Miretsky, G.I., Troitskaya, M.N., Dudarev, A.A., 1993. Radioecological peculiarities around the Novaya Zemlya (USSR) atomic test range. Int. J. Radiat. Hyg., Vol. 1, pp. 1–13.

46. Chappell, A., Hancock, G., Rossel, R.A.V., Loughran, R., 2011. Spatial uncertainty of the 137Cs reference inventory for Australian soil. J. Geophys. Res., Vol. 116, F04014. – Available on: http:// onlinelibrary.wiley.com/doi/10.1029/2010JF001942/epdf > (accessed 08 March 2018).

47. Blagoeva, R., Zikovsky, L., 1995. Geographic and vertical distribution of Cs-137 in soil in Canada. J. Environ. Radioact., Vol. 27, pp. 269–274.

48. Palsson, S.E., Arnalds, O., Sigurgeirsson, M.A., Gudnason, K., Howard, B.J., Wright, S., Palsdottir, P., 2002. Cs-137 fallout deposition in Iceland: predictions, measurements and assessments impact. Radioprotection – Colloques, Vol. 37, pp. Cl-1223–1228. – Available on: http://www.radioprotection.org/articles/radiopro/pdf/2002/05/rad20021pC1-1223.pdf> (accessed 01 February 2018).

49. Bergan, T.D., 2002. Radioactive fallout in Norway from atmospheric nuclear weapons tests. J. Environ. Radioact., Vol. 60, pp. 189–208.

50. Isaksson, M., Erlandsson, B., Linderson, M.-L., 2000. Calculation of the deposition of 137Cs from the nuclear bomb tests and from the Chernobyl accident over the province of Skåne in the southern part of Sweden based on the precipitation. J. Environ. Radioact., Vol. 49, pp. 97–112.