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Takahashi, Fumiaki; Yamaguchi, Yasuhiro
Radiation Risk Assessment Workshop Proceedings, p.71 - 78, 2003/00
Conversion from tooth enamel dose to organ doses against external photon exposure were studied in order to develop a method that can retrospectively estimate organ doses by the Electron Spin Resonance (ESR) dosimetry using tooth samples. Monte Carlo calculations using EGS4 code were performed to obtain dose to tooth enamel and organ doses by using a modified MIRD-type phantom. The Electron Spin Resonance (ESR) dosimetry using tooth samples and dose measurements using thermo-luminescence dosimeters (TLDs) were also carried out to examine dose to teeth region with a realistic physical phantom. A Voxel-type phantom was constructed from CT images of the physical phantom. Monte Carlo calculations with the Voxel-type phantom were performed to verify the results of the experiments and enamel doses calculated by use of the modified MIRD-type phantom. The obtained data are to be useful for the retrospective assessment of individual dose in past exposure events by the ESR dosimetry with tooth enamel.
Takahashi, Fumiaki; Yamaguchi, Yasuhiro; Iwasaki, Midori*; Miyazawa, Chuzo*; Hamada, Tatsuji*; Saito, Kimiaki
Journal of Nuclear Science and Technology, 39(9), p.964 - 971, 2002/09
Times Cited Count：6 Percentile：39.48(Nuclear Science & Technology)Conversion from tooth enamel dose to organ doses was analyzed to establish a method of retrospective individual dose assessment against external photon exposure by the Electron Spin Resonance (ESR) dosimetry. Dose to tooth enamel was obtained by Monte Carlo calculations using a modified MIRD-type phantom. The calculated tooth enamel doses were verified by measurements with thermo-luminescence dosimeters inserted in a physical head phantom. Energy and angular dependences of tooth enamel dose were compared with those of other organ doses. Additional Monte Carlo calculations were performed to study the effects of human model on the tooth enamel dose with a voxel-type phantom, which was based on CT images of the physical phantom. The data derived with the modified MIRD-type phantom were applied to convert from tooth enamel dose to organ doses against external photon exposure in a hypothesized field, where scattered radiations were taken into account. The results indicated that energy distribution of photons incident to a human body should be required to evaluate precisely individual dose by the ESR dosimetry using teeth.
