[A problem with ESR dosimetry utilizing human tooth enamel in low dose region].

Experiments were made to determine the dependence of CO3(3-) signal intensity on radiation dose in the low dose region from 3.1 x 10(-4) C/kg to 865.6 x 10(-4) C/kg. After all human tooth enamel samples were crushed into 350-500 micrometers particles, they were irradiated with 60Co gamma rays. Irradiated samples were measured with the ESR instrument, and the CO3(3-) signal appearance and the true signal have been determined. It is confirmed that the relation between the true intensity of the CO3(3-) signal and the exposure have linearity from 25.0 x 10(-4) C/kg to 865.6 x 10(-4) C/kg. It is difficult to confirm this in the case of less than 25.0 x 10(-4) C/kg due to the effect of organic signal and noise.