Research

Center for Environmental DentistryCenter for Environmental Dentistry

 The accident at the Fukushima Daiichi Nuclear Power Station during the Great East Japan earthquake in March 2011 was environmentally detrimental in surrounding areas centred in the Fukushima Prefecture. It is an important social issue to clarify how the environmental pollution caused by radioactive substances affects the health of residents.

 Teeth tend to incorporate and accumulate various radioactive substances such as strontium-90 and caesium-137 from the environment. We can therefore estimate the status of radiation exposure in humans and animals by measuring the radionuclides incorporated into teeth. The Tohoku University Graduate School of Dentistry established the Center for Environmental Dentistry in April 2013. This research center has obtained various research funds so far, and has collected a large number of teeth from various animals in the Fukushima disaster area after the accident. Further, we have collected more than 8,000 human milk teeth from all over Japan and archived them. Then, we have established a new radiation exposure dose evaluation method using these teeth, and while performing accurate radiation exposure dose measurements, we have also worked to return the results to local residents. The research conducted at this research center is carried out in close collaboration with researchers from other faculties and other universities in different fields of specialization, and is characterized by an extremely strong interdisciplinary tinge. While maintaining this research system, this research center will continue to record important basic data related to the Fukushima Daiichi Nuclear Power Plant accident that should be handed down to future generations. 

Director: Dr. Ken Osaka, Professor

Staff

  •  

    Prof. Ken Osaka,

  •  

    Associate Prof. Atsushi Takahashi,

  •  

    Associate Prof. Toshihiko Suzuki,

  • Emeritus Prof. Hisashi Shinoda,

  • Senior Assist. Prof. Mirei Chiba,

Topics of Research

  • Comprehensive dose evaluation project for disaster-affected animals. (Tohoku University President's Discretionary Expenses / Special Expenses from Ministry of Education, Culture, Sports, Science and Technology, 2011-2015).
  • Development and pharmacokinetic analysis of radioactive cesium and pre-slaughter estimation technology for meat livestock. (Practical technology development project consigned by the Ministry of Agriculture, Forestry and Fisheries, 2011-2013).
  • Analysis of human internal exposure to radiation using teeth. (Special grant from the International Research Institute of Disaster Science, Tohoku University, 2012-2015).
  • Comprehensive assessment of internal exposure to radiation using teeth (Budget for nuclear disaster impact survey on radiation health effects, Ministry of Environment, 2013-2015).
  • Screening of internal exposure to radiation using teeth. (Grant-in-Aid for Scientific Research (B), Japan Society for the Promotion of Science, 2015-2019).
  • Dosimetric assessment of radiation exposure using deciduous teeth collected from children in Fukushima. (Budget for nuclear disaster impact survey on radiation health effects, Ministry of Environment, 2016-2018, 2019-2021).
  • Pluralistic approach for elucidating biological effects of radiation using animal models. (National issue-based R&D promotion project for the nuclear science and technology / Human resources development promotion project that brings together wisdom, Ministry of Education, Culture, Sports, Science and Technology, 2017-2019).
  • Dosimetry and reproductive function assessment in high natural radiation areas in India and Japan. (International Joint Research Acceleration Fund (B), Japan Society for the Promotion of Science, 2019-2022).
  • Comprehensive dose assessment using human teeth in the environment after the Fukushima Daiichi accident. (Grant-in-Aid for Scientific Research (B), Japan Society for the Promotion of Science, 2015-2019).

Recent Publications

  1. Yusuke Mitsuyasu , Toshitaka Oka , Atsushi Takahashi, Yasushi Kino , Kenichi Okutsu, Tsutomu Sekine, Takuma Yamashita, Yoshinaka Shimizu , Mirei Chiba, Toshihiko Suzuki, Ken Osaka, Keiichi Sasaki , Masatoshi Suzuki , Manabu Fukumoto , Hisashi Shinoda: Estimation of external dose for wild Japanese macaques captured in Fukushima prefecture: Decomposition of electron spin resonance spectrum. Radiation Protection Dosimetry 199(14):1620-1625 (2023). 
  2. Kohei Oda, Yusuke Mitsuyasu, Takuma Yamashita, Yasushi Kino, Kenichi Okutsu, Tsutomu Sekine, Atsushi Takahashi, Hisashi Shinoda: Development of a method for estimating radionuclides in samples using an imaging plate. KEK Proceedings 2023-2 :115-119 (2023)
  3. Toshitaka Oka, Atsushi Takahashi, Kazuma Koarai, Yasushi Kino, Tsutomu Sekine, Yoshinaka Shimizu, Mirei Chiba, Toshihiko Suzuki, Ken Osaka, Keiichi Sasaki, Hisashi Shinoda: Detection limit of electron spin resonance for Japanese deciduous tooth enamel and density separation method for enamel–dentine separation. Journal of Radiation Research 63(4):609-614(2022)
  4. Kazu Nihei, Syun Tokita, Hideaki Yamashiro, Valerie Goh Swee Ting, Ryo Nakayama, Yohei Fujishima, Yasushi Kino, Yoshinaka Shimizu, Hisashi Shinoda, Kentaro Ariyoshi, Kosuke Kasai, Yasuyuki Abe, Manabu Fukumoto, Akifumi Nakata, Tomisato Miura:Evaluation of sperm fertilization capacity of large Japnese field mice(Apodemus speciousus) exposed to chronic low dose rate radiation after the Fukushima accident. Journal of Radiation Research and Applied Sciences 15(3): 186-190 (2022)
  5. Takahashi A, Chiba M, Tanahara A, Aida J, Shimizu Y, Suzuki T, Murakami S, Koarai K, Ono T, Oka T, Ikeyama J, Kaneko O, Unno M, Hirose K, Ohno T, Yasushi Kino, Sekine T, Osaka K, Sasaki K, Shinoda H.: Radioactivity and radionuclides in deciduous teeth formed before the Fukushima-Daiichi Nuclear Power Plant accident. Scientific Reports 14:11(1) 10335 (2021)
  6. Koarai K, Matsueda M, Aoki J, Yanagisawa K, Terashima M, Fujiwara K, Kino Yasushi, Oka T, Takahashi A, Suzuki T, Shimizu Y, Chiba M, Osaka K, Sasaki K, Sekine T, Fukumoto M, Shinoda H, Kitamura A, Abe. H.: Rapid analysis of Sr-90 in cattle bone and tooth samples by inductively coupled plasma mass spectrometry. Journal of Analytical Atomic Spectrometry 36(8): 1678-1682 (2021)
  7. Kazuki Komatsu, Tsugumi Iwasaki, Kosuke Murata, Hideaki Yamashiro, Valerie Swee Ting Goh, Ryo Nakayama, Yohei Fujishima, Takumi Ono, Yasushi Kino, Yoshinaka Simizu, Atsushi Takahashi, Hisashi Shinoda, Kentaro Ariyoshi, Kosuke Kasai, Masatoshi Suzuki, Maria Grazia Palmerini, Manuel Belli, Guido Macchiarelli, Toshitaka Oka, Manabu Fukumoto, Mitsuaki A. Yoshida, Akifumi Nakata, Tomisato Miura: Morphological reproductive characteristics of testes and fertilization capacity of cryopreserved sperm after the Fukushima accident in raccoon (Procyon lotor ) . Reproduction in Domestic Animals 56(3): 484-497 (2021)
  8. Toshitaka Oka, Atsushi Takahashi, Kazuma Koarai, Yusuke Mitsuyasu, Yasushi Kino, Tsutomu Sekine, Yoshinaka Shimizu, Mirei Chiba, Toshihiko Suzuki, Ken Osaka, Keiichi Sasaki, Yusuke Urushihara, Satoru Endo, Masatoshi Suzuki, Hisashi Shinoda, Manabu Fukumoto: External exposure dose estimation by electron spin resonance technique for wild Japanese macaque captured in Fukushima Prefecture. Radiation Measurements 134:106315-106315 (2020)
  9. Kentaro Ariyoshi, Tomisato Miura, Kosuke Kasai, Valerie Swee Ting Goh, Yohei Fujishima, Akifumi Nakata, Atsushi Takahashi, Yoshinaka Shimizu, Hisashi Shinoda, Hideaki Yamashiro, Colin Seymour, Carmel Mothersill, Mitsuaki A. Yoshida: Environmental radiation on large Japanese field mice in Fukushima reduced colony forming potential in hematopoietic progenitor cells without inducing genomic instability. International Journal of Radiation Biology 98(6):1147-1158 (2020)
  10. Kazuki Saito, Kengo Kuroda, Rie Suzuki, Yasushi Kino, Tsutomu Sekine, Hisashi Shinoda, Hideaki Yamashiro, Tomokazu Fukuda, Jin Kobayashi, Yasuyuki Abe, Junko Nishimura, Yusuke Urushihara, Hiroshi Yoneyama, Manabu Fukumoto, Emiko Isogai: Intestinal bacteria as powerful trapping lifeforms for the elimination of radioactive cesium.   Frontiers in Veterinary Science 6 :70 (2019)
  11. Urushihara Y, Suzuki T, Shimizu Y, Ohtani M, Kuwahara Y, Suzuki M, Uno T, Fujita S, Saito A, Yamashiro H, Kino Y, Sekine T, Shinoda H, Fukumoto M: Haematological analysis of Japanese macaques (Macaca fuscata) in the area affected by the Fukushima Daiichi Nuclear Power Plant accident. Scientific Reports 8, 16748 (2018).
  12. Koarai K, Kino Y, Takahashi A, Suzuki T, Shimizu Y, Chiba M, Osaka K, Sasaki K, Fukuda T, Isogai E, Yamashiro H, Oka T, Sekine T, Fukumoto M, Shinoda H: 90Sr specific activity of teeth of abandoned cattle after the Fukushima accident – teeth as an indicator of environmental pollution. J Environ Radioactivity 183, 1-6 (2018)
  13. Takino S, Yamashiro H, Sugano Y, Fujishima Y, Nakata A, Kasai K, Urushihara Y, Suzuki M, Shinoda H, Miura T, Fukumoto M: Analysis of the effect of chronic and low-dose radiation exposure on spermatogenic cells of male large Japanese field mice (Apodemus speciosus) after the Fukushima Daiichi Nuclear Power Plant accident. Radiation Research 187, 161−168 (2017)
  14. Koarai K, Kino Y, Nishiyama J, Takahashi A, Suzuki T, Shimizu Y, Chiba M, Osaka K, Sasaki K, Fukuda T, Isogai E, Oka T, Sekine T, Fukumoto M, Shinoda H.: Estimation of environmental pollution after the Fukushima Daiichi Nuclear Power Plant accident by measurement of radioactivities in teeth. Proceedings of the 18th Workshop on Environmental Radioactivity 202-207 (2017)
  15. Nishiyama J, Koarai K, Kino Y, Shimizu Y, Takahashi A, Suzuki T, Chiba M, Osaka K, Sasaki K, Fukuda T, Isogai E, Oka T, Sekine T, Fukumoto M, Shinoda H.: Correlation of Sr-90 activity concentration between the tooth and bone of cattle suffered from Fukushima Daiichi Nuclear Power Plant accident. Proceedings of the 18th Workshop on Environmental Radioactivity. 196-201 (2017)
  16. Takino S, Yamashiro H, Sugano Y, Fujishima Y, Nakata A, Kasai K, Urushihara Y, Suzuki M, Shinoda H, Miura T, Fukumoto M: Analysis of the effect of chronic and low-dose radiation exposure on spermatogenic cells of male large Japanese field mice (Apodemus speciosus) after the Fukushima Daiichi Nuclear Power Plant accident. Radiation Research 187: 161−168 (2017)
  17. Urushihara Y, Kawasumi K, Endo S, Tanaka K, Hirakawa Y, Hayashi G, SEKINE T, Kino Y, Kuwahara Y, Suzuki M, Fukumoto M, Yamashiro H, Abe Y, Fukuda T, Shinoda H, Isogai E, Arai T, Fukumoto M: Analysis of plasma protein concentrations and enzyme activities in cattle within the ex-evacuation zone of the Fukushima Daiichi Nuclear Plant accident. PLos One 11(5): e0155069 (2016)
  18. Koarai K, Kino Y, Takahashi A, Suzuki T, Shimizu Y, Chiba M, Osaka K, Sasaki K, Fukuda T, Isogai E, Yamashiro H, Oka T, Sekine T, Fukumoto M, Shinoda H: 90Sr in teeth of cattle abandoned in evacuation zone: Record of pollution from the Fukushima Daiichi Nuclear Power Plant accident. Scientific Reports 6: 24077 (2016)
  19. Fukuda T, Hiji M, Kino Y, Abe Y, Yamashiro H, Kobayashi J, Shimizu Y, Takahashi A, Suzuki T, Chiba M, Inoue K, Kuwahara Y, Morimoto M, Katayama M, Donai K, Shinoda H, Sekine T, Fukumoto M, Isogai E: Software development for estimating the cesium radioactivity in skeletal muscle from that in blood of cattle. Animal Science Journal 87(6):842-7 (2016)
  20. Fukuda T, Kino Y, Abe Y, Yamashiro H, Kobayashi J, Shimizu Y, Takahashi A, Suzuki T, Chiba M, Takahashi S, Inoue K, Kuwahara Y, Morimoto M, Shinoda H, Hiji M, Sekine T, Fukumoto M, Isogai E: Cesium radioactivity in peripheral blood is linearly correlated to that in skeletal muscle: Analyses of cattle within the evacuation zone of the Fukushima Daiichi Nuclear Power Plant. Animal Science Journal 86, 120−124 (2015)
  21. Yamashiro H, Abe Y, Fukuda T, Kino Y, Kawaguchi I, Kuwahara Y, Fukumoto Mo, Takahashi S, Suzuki M, Kobayashi J, Uematsu E, Tong B, Yamada T, Yoshida S, Shinoda H, Sato E, Sekine T, Isogai E, Fukumoto M: Effects of radioactive caesium on bull testes after the Fukushima nuclear plant accident. Scientific Reports 3, 2850 (2013)
  22. Fukuda T, Kino Y, Abe Y, Yamashiro H, Kuwahara Y, Nihei H, Sano Y, Irisawa A, Shimura T, Fukumoto M, Shinoda H, Obata Y, Saigusa S, Sekine T, Isogai E, Fukumoto M: Distribution of artificial radionuclides in the abandoned cattle in the evacuation zone of the Fukushima Daiichi Nuclear Power Plant. PLos One 8, e54312 (2013)

Laboratory Contacts

Eriko Shiozawa

@

Research