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I/
I and 
C records in a modern coral from Rowley Shoals off northwestern Australia reflect the 20th-century human nuclear activities and ocean/atmosphere circulationsMitsuguchi, Takehiro; Okabe, Nobuaki*; Yokoyama, Yusuke*; Yoneda, Minoru*; Shibata, Yasuyuki*; Fujita, Natsuko; Watanabe, Takahiro; Kokubu, Yoko
Journal of Environmental Radioactivity, 235-236, p.106593_1 - 106593_10, 2021/09
Times Cited Count：5 Percentile：35.21(Environmental Sciences)For a contribution to developing the usage of iodine-129 (I) as a tracer of deep-seated fluid, I/I and C were measured for annual bands (AD 1931-1991) of a modern coral collected from Northwestern Australia; the measurements were performed using the JAEA-AMS-TONO-5MV for I/I and an AMS facility of the University of Tokyo for C. Results indicate that both I/I and C distinctly increase from 1950s. The C increase can be ascribed to atmospheric nuclear tests, while the I/I increase is due to nuclear-fuel reprocessing as well as atmospheric nuclear tests. These results are in good agreement with previous studies, indicating that the I/I measurement by JAEA-AMS-TONO-5MV has been further developed.
Hirouchi, Jun; Takahara, Shogo; Komagamine, Hiroshi*; Kato, Nobuyuki*; Matsui, Yasuto*; Yoneda, Minoru*
Journal of Radiological Protection, 41(3), p.S139 - S149, 2021/09
Times Cited Count：2 Percentile：31.78(Environmental Sciences)Sheltering is one of the countermeasures for protection against radiation exposures in nuclear accidents. The effectiveness of sheltering is often expressed by the reduction factor, that is the ratio of the indoor to the outdoor cumulative radioactivity concentrations or doses. The indoor concentration is mainly controlled by the air exchange rate, penetration factor, and indoor deposition rate. The penetration factor and indoor deposition rate depend on the surface and opening materials. We investigated experimentally these parameters of I
and particles. The experiment was performed in two apartment houses, three single-family houses, and chambers. The obtained penetration factor ranged 0.3 
1 for particles of 0.3 1 
m and 0.15 0.7 for I depending on the air exchange rate. The indoor deposition rate for a house room ranged 0.007 0.2 h
for particles of 0.31 m and 0.21.5 h for I depending on floor materials.
Kimura, Tatsuki*; Fukutani, Satoshi*; Ikegami, Maiko*; Sakamoto, Fuminori; Kozai, Naofumi; Grambow, B.*; Yoneda, Minoru*
Chemosphere, 276, p.130121_1 - 130121_7, 2021/08
Times Cited Count：1 Percentile：6.09(Environmental Sciences)The adsorption of cesium (Cs) on biotite and dissolution of Cs from Cs-bearing biotite using a siderophore were investigated aiming to contribute to the elucidation of radiocesium migration mechanisms in the soil environment. Cs was adsorbed on a hardly weathered biotite powder sample. A siderophore was extracted and purified from the bacterial culture medium, and the purified siderophore was used in five consecutive dissolution experiments of the biotite samples. The major components of the biotite (Al, Fe, and Mg) were dissolved almost stoichiometrically, strongly suggesting that the siderophore selectively dissolves the broken edges of the biotite. The Cs adsorbed on the broken edges was dissolved rapidly as the siderophore dissolved the broken edges, and then, the Cs adsorbed on the outer planar surface of the biotite particles was slowly dissolved.
Takahara, Shogo; Iijima, Masashi*; Yoneda, Minoru*; Shimada, Yoko*
Risk Analysis, 39(1), p.212 - 224, 2019/01
Times Cited Count：5 Percentile：48.71(Public, Environmental & Occupational Health)A dose assessment model was developed based on measurements and surveys of individual doses and relevant contributors in Fukushima City for four population groups: Fukushima City Office staff, Senior Citizens' Club, Contractors' Association, and AgriculturalCooperative. In addition, probabilistic assessments were performed for these population groups by considering the spatial variability of contamination and interpopulation differencesresulting from behavior patterns. As a result of comparison with the actual measurements, the assessment results for participants from the Fukushima City Office, Senior Citizens' Club and the Agricultural Cooperative agreed with the measured values. By contrast, the measurements obtained for the participants from the Contractors' Association were not reproduced well in the present study. To assess the doses to this group, further investigations of association members' work activities and the related dose reduction effects are needed.
Pratama, M. A.; Takahara, Shogo; Munakata, Masahiro; Yoneda, Minoru*
Environment International, 115, p.196 - 204, 2018/06
Times Cited Count：2 Percentile：7.2(Environmental Sciences)Takahara, Shogo; Ikegami, Maiko*; Yoneda, Minoru*; Kondo, Hitoshi*; Ishizaki, Azusa; Iijima, Masashi; Shimada, Yoko*; Matsui, Yasuto*
Risk Analysis, 37(7), p.1256 - 1267, 2017/07
Times Cited Count：6 Percentile：52.04(Public, Environmental & Occupational Health)Takahara, Shogo; Homma, Toshimitsu; Yoneda, Minoru*; Shimada, Yoko*
Hoken Butsuri, 51(3), p.147 - 159, 2016/09
no abstracts in English
Takahara, Shogo; Ikegami, Maiko*; Yoneda, Minoru*; Kondo, Hitoshi*; Ishizaki, Azusa; Shimada, Yoko*
Dai-21-Kai Chikasui, Dojo Osen To Sono Boshi Taisaku Ni Kansuru Kenkyu Shukai Koenshu (CD-ROM), p.505 - 510, 2015/06
Doses received by the public are necessary information in management of radiation exposures in areas contaminated by the Fukushima Daiichi Nuclear Power Plant (1F) accident. Direct ingestion of contaminated soil is one of the exposure pathways which is a concern for the people living in the areas in terms of children's exposure. Therefore in order to manage efficiently the middle and the long term exposures with a sense of safety of the people, we have to clarify the contribution of this pathway to the doses received by those. However, a fractional absorption of radioactive cesium in gastrointestinal system has not been evaluated yet. We evaluated this factor based on the results of a physiologically based extraction test and an extraction test with hydrochloric acid, which is adopted in Japanese national law to evaluate a fractional absorption of heavy metals in gastrointestinal system. In addition, we assessed the doses to the public from this pathway after the 1F accident.
Kumamoto, Yuichiro*; Aramaki, Takafumi*; Watanabe, Shuichi*; Yoneda, Minoru*; Shibata, Yasuyuki*; Togawa, Orihiko; Morita, Masatoshi*; Shitashima, Kiminori*
Journal of Oceanography, 64(3), p.429 - 441, 2008/06
Times Cited Count：11 Percentile：25.5(Oceanography)In 1995 and 2000, radiocarbon ratio (C) of total dissolved inorganic carbon was measured in the Japan Sea, a semi-closed marginal sea in the western North Pacific, where deep and bottom waters are formed in itself. Compiling them with historical radiocarbon data in the Japan Sea, temporal and spatial variations of the radiocarbon in the bottom water below 2000 m depth were elucidated. C in the bottom waters in the western Japan and Yamato Basins increased by about 20 ‰ between 1977/79 and 1995 and did not changed between 1995 and 1999/2000, suggesting penetration of surface bomb-produced radiocarbon into the bottom waters due to bottom ventilation in the earlier period and stagnation of the bottom ventilation in the following period, respectively. In the eastern Japan Basin, the bottom C increased by about 10 ‰ between 1977/79 and 2002, suggesting less ventilation of the bottom water in the basin. The temporal changes of the radiocarbon, tritium, and dissolved oxygen suggest sporadic occurrences of the bottom ventilation between 1979 and 1984 and its stagnation between 1984 and 2004 in the eastern Japan and Yamato Basins. The former is probably due to spreading of a newly ventilated bottom water in the western Japan Basin in the severe winter of 1976-1977 along the abyssal circulation in the Japan Sea. The latter does not conflict with temporal changes of bomb-produced 
Cs and chlorofluorocarbon-11 in the bottom water.
; Yoneda, Shigeo*; Koyakaichi, Minoru*
PNC TJ7308 93-005, 292 Pages, 1993/03
no abstracts in English
Yoneda, Shigeo*; Koyakaichi, Minoru*; Sakuramoto, Yuji*
PNC TJ7308 91-001VOL1, 119 Pages, 1991/03
PNC-TJ7308-91-001VOL1.pdf:3.08MB
no abstracts in English
Takahara, Shogo; Shimada, Yoko*; Yoneda, Minoru*; Iijima, Masashi
no journal, ,
Pratama, M. A.; Takahara, Shogo; Munakata, Masahiro; Homma, Toshimitsu; Yoneda, Minoru*
no journal, ,
Pratama, M. A.; Takahara, Shogo; Munakata, Masahiro; Yoneda, Minoru*
no journal, ,
Hirouchi, Jun; Takahara, Shogo; Komagamine, Hiroshi*; Munakata, Masahiro; Kimoto, Shigeru*; Yoneda, Minoru*; Matsui, Yasuto*
no journal, ,
no abstracts in English
Kimoto, Shigeru*; Sadatani, Yoshiro*; Yoneda, Minoru*; Matsui, Yasuto*; Hirouchi, Jun
no journal, ,
no abstracts in English
Kimoto, Shigeru*; Shiota, Kenji*; Nishiguchi, Kohei*; Matsui, Yasuto*; Hirouchi, Jun; Yoneda, Minoru*
no journal, ,
no abstracts in English
Shakagori, Shota*; Murai, Chiaki*; Kimoto, Shigeru*; Matsui, Yasuto*; Yoneda, Minoru*; Hirouchi, Jun
no journal, ,
no abstracts in English
Takahara, Shogo; Pratama, M. A.*; Ikegami, Maiko*; Fukutani, Satoshi*; Yoneda, Minoru*
no journal, ,
We experimentally evaluated the absorption fraction in gastrointestinal system of Cs-137 in wild boar meat contaminated by the Fukushima Daiichi Nuclear Power Plant accident. Wild boar was hunted in difficult-to-return zone in December 2017. For three parts of the meat (Loin, Brisket, Round), extraction tests were performed based on in-vitro digestion method by Minekus et al. (2014). From this test, the extraction rate in small intestinal was evaluated as 89%
3%.
Hirouchi, Jun; Takahara, Shogo; Komagamine, Hiroshi*; Kato, Nobuyuki*; Matsui, Yasuto*; Yoneda, Minoru*
no journal, ,
Sheltering is one of the countermeasures for protection against radiation exposures in nuclear accidents. The effectiveness of sheltering is often expressed by the reduction factor, that is the ratio of the indoor to the outdoor cumulative radioactivity concentrations or doses. The indoor concentration is mainly controlled by the air exchange rate, penetration factor, and indoor deposition rate. The penetration factor and indoor deposition rate depend on the surface and opening materials. We investigated experimentally these parameters of I and particles. The experiment was performed in two apartment houses, three single-family houses, and chambers. The obtained penetration factor ranged 0.3 1 for particles of 0.3 1 m and 0.1 0.6 for I depending on the air exchange rate. The indoor deposition rate for a house room ranged 0.007 0.2 h for particles of 0.31 m and 0.21.5 h for I depending on floor materials.
