English Abstracts
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English abstracts 2S01 Establishment and the present status of The radioactive particles have been emitted animal archives in and around the ex- to environment in the Fukushima Daiichi Nuclear evacuation zone of the Fukushima Daiichi Power Plant accident in 2011. At least these Nuclear Power Plant (FNPP) accident particles were emitted from the units 1 and 2. FUKUMOTO, M.1, THE GROUP FOR However, the details have not been clarified yet. COMPREHENSIVE DOSE EVALUATION IN This study performed isolation of radioactive ANIMALS FROM THE FNPP AFFECTED particles including so-called Cs bearing particles, AREA2 from soil samples, and performed (1, 2Tohoku Univ.) characterization. And we disclosed differences The Fukushima Daiichi Nuclear Power between the particles from the units 1 and 2. We Plant (FNPP) accident released large amounts of isolated each four radioactive particles from two radioactive substances into the environment. soil samples. The radionuclides 134Cs and 137Cs Since the FNPP accident, major concern in the were detected by gamma spectroscopy in all of world has been the health effect of long-term low the particles. However, no other gamma emitters dose exposure to both internal and external were detected in the particles. The specific radiations. However, it is impossible to perform radioactivity of particles from unit 1 is lower than such exposure experiments including laboratory that from unit 2. A significant amount of Ba has animals. The very important characteristics of the been detected in the particles from unit 1. FNPP accident is that the accident happened in However, distribution of Ba were different from Japan which is one of the most advanced and that of Cs. For this reason, origin of Ba could not open countries and the amount of released be a decay product of Cs. In addition, a radionuclides was 1/10 of the Chernobyl accident. distribution of Fe and Zn were not consistent with We collected organ specimens from cattle, pigs that of Cs. In contrast, Si and Ca were detected in and wild Japanese monkeys within and adjacent common. Si is one of major components in the to the 20-km radius previously set as the radioactive particles emitted by the Fukushima evacuation zone of FNPP. We have been accident. performing determination of organ concentrations of radionuclides and their biological effects. I will address how we have 1A02 Development of rapid separation established the archive system, what we knew method of plutonium and americium using our archive system, and problems we are contained in the soil sample facing at. SUZUKI, K., UESUGI, M., YAMAMORI, K.,YOKOYAMA,A., (Gread. School Nat. Sci. Tech., Kanazawa Univ.) 1A01 Differences by the source reactor of the Artificial elements of Pu and Am generated radioactive particles emitted from the in nuclear fuel are known to be released from Fukushima Dai-ichi Nuclear Power Plant Fukushima Nuclear Power Plant in March, 2011. accident In this study, we aim to develop a rapid SATOU, Y.1, ADACHI, K.2, ONO, T.1, IIZAWA, quantitative analysis of Pu and Am in the soil Y. 2, ABE, Y.1, NAKAI, I.2, IGARASHI, Y.1, sample for nuclear emergency. We focused firstly SASA, K.2, SUEKI, K.2, on dissolution and pre-concentration, and (1University of Tsukuba, 2Meteorological secondly, on speeding up purification for Am in Research Institute, 3Tokyo University of Science) the sequential analysis. The ammonium nitrate 149 fusion and the purification of Am by a DGA resin column have been examined. In the procedure, DDTC solvent extraction was found necessary to 1A04 Dynamism of radioactive cesium in eliminate polonium atoms. Finally, we ensured blood and muscle of cattle fed with radioactive that these procedures were applicable to the soil contaminated silage samples for monitoring contamination in SUZUKI, M.1, SUZUKI, H.2, ISHIGURO, H.2, Fukushima. KINO, Y.2, URUSHIHARA, Y.1, WATANABE, S.2, SAITO, Y.2, KOZUTSUMI, T.2, SOCHI, Y.4, NISHI, K.4, ABIKO, R.1, WASHIO, R.1, KUWAHARA, Y.1, NUMABE, T.2, SEKINE, T.5, 1A03 A Cesium detachment from the clay FUKUMOTO, M.1 minerals using molten salt treatment and (1IDAC, Tohoku Univ., 2Miyagi Prefect. Livest. structure analysis Expt. Stn., 3Dept. Chem., Tohoku Univ., 4Sendai HONDA, M. 1, SHIMOYAMA, I. 1, KOGURE, T. Livest. Hyg. Ctr., 5IEHE, Tohoku Univ.) 2, OKAMOTO, Y. 1, SUZUKI, S. 1, YAITA, T. 1 We investigated the correlation of internal (1JAEA, 2Tokyo Univ.) radiocesium deposition determined by blood There is the issue of soil contamination monitoring and by surface monitoring on the neck problem with the radioactive cesium (Cs) large or ramp muscle of live-cattle using a NaI quantities scattering with the Fukushima first surveymeter. Blood and muscle radiocesium Nuclear Power Plant accident without the still concentration was measured in a Ge spectrometer. radical solution that nearly four years passed Seven-month-old or matured Japanese black being done by outbreak. The molten salt cattle were fed with radiocesium-contaminated treatment method is one of the effective Cs silage for approximately 60 days, thereafter, with removals, however, waste increases in thing and contamination free clean silage. detachment needing a high temperature Surface monitoring values (cps) were well processing process and still has a problem for correlated with radiocesium concentration practical use. In this study, we investigated the Cs (Bq/kg) in the dissected muscle. Therefore, we detachment by the low pressure sublimation could convert the surface monitoring value to method using the molten salt (NaCl, CaCl2 mixed radiocesium concentration in the muscle. We salt) and the structure analysis at the Cs removal further compared surface monitoring data with from clay minerals and a reuse materials search. blood monitoring data. Radiocesium appeared to When we gave low-pressure processing with accumulate in muscle and blood with similar NaCl, CaCl2 mixed salt and heated, we achieved kinetics over the period of feeding with the Cs removal rate 100% at 700 degrees. As a result contaminated silage. On the other hand, the of structure analysis of the clay minerals which decrease in the muscle was slower than that in occurred in a heating process using X-rays blood after switching to the clean silage. It was diffraction method (XRD) and transmission confirmed that biological halflife (Tb) was electron microscope (TEM-EDS), Cs formed the approximately 2 weeks and 1 month in blood and plural structure called the Calcite, Hematite, the muscle, respectively. We also found the age- Augite, and Wadalight and knew that Cs was dependent elongation of Tb in the muscle. removed while the frame structure of clay The present study revealed that internal minerals changed. radiocesium deposition can be estimated by surface monitoring, as the noninvasive method. 150 We will discuss conditions to be considered for preparation of candidate material and calculating surface monitoring values to muscle evaluation of homogeneity radiocesium concentrations. MIURA, T.,1 MINAI, Y.,2 HIRAI, S.3, IWAMOTO, H.4, YONEZAWA, C.5, KAKITA, K.6, KOJIMA, I.6, OKADA, A.7, OKADA, Y.8, SANADA, T.9, SHIBUKAWA, M.10, 1A05 Strontium-90 in fishes after the TAKAGAI, Y.11, ARAKAWA, F.12, MAEYAMA, Fukushima Dai-ichi Nuclear Power Plant K.13, YAMADA, T.14, OTA, H.15, FURUKAWA, accident M.16, UEMATSU, Y.17 MIKI, S.1, FUJIMOTO, K. 1, MORITA, T. 1, (1NMIJ/AIST, 2Musashi Univ., 3Tokyo City Univ., SHIGENOBU, Y. 1, TAKAGI, K. 1, ONO, T. 1, 4Enivironmental Technology Service, 5CPDNP, WATANABE, T. 2, SUGISAKI, H. 1 6JSAC, 7Toshiba Environmental Solution, 8Tokyo (1Ntl. Res. Inst. of Fish. Sci, 2Tohoku Ntl. Fish. City Univ. Atomic Energy Research Lab., Res. Inst.) 9Hokkaido Univ. of Sci., 10Saitama Univ., Radioactive wastewater released from the 11Fukushima Univ., 12NH Foods R&D center, Fukushima Dai-ichi Nuclear Power Plant 13JCAC, 14JRIA, 15KANSO, 16PerkinElmer, (FDNPP) includes the high concentration of 90Sr. 17JAB) After the wastewater was discharged into the sea, Following the mega earthquake, tsunami, 90Sr in seawater were only temporarily detected and the accident at the Fukushima Daiichi nuclear near the FDNPP harbor. Strontium-90 in seawater power plant on 3.11.2011, a massive amount of was spread across the ocean and diluted to radioactive nuclides were released into the undetectable level. Even though 90Sr in marine environment in Japan. The emergency situation fishes are not detected, citizens raised questions required urgent measurements of radioactive about the safety of the fishes because of releasing isotopes in environmental samples and food the high concentrations of 90Sr from the FDNPP. samples for human health. It was required that the Therefore, in this study, we investigated the certified reference material of food sample for concentrations of 90Sr in marine fishes collected validation of measurement of radioactive from the coast of east Japan. The concentration of isotopes because the certified reference material 90Sr in various fishes caught around the coast of is essential for accurate and precise measurement east Japan was the same as that before the of radioactive isotopes in these samples. We have accident. Although the concentration of 90Sr in developed and supplied the certified reference Sebastes cheni caught near the FDNPP in Dec. material of food and environmental samples. The 2011 was 1.2 Bq/kg w.w. that of in S. cheni caught developed certified reference materials are brown off Fukushima prefecture in Jun 2012 was rice grain, beef flake, soybean powder, shiitake undetectable. Therefore we suggest that the mushroom powder, in which certified massic contamination of 90Sr in marine fishes may be activities (Bq kg-1) of 134Cs, 137Cs and 40K. In this localized to a small region near the FDNPP harbor. paper, we described the development of certified All the results showed the concentration of 90Sr in reference material of fish bone ash (90Sr, 134Cs, marine fishes was notably lower than that of 137Cs.