Complex experimental research on internal tooth dosimetry for the Techa River region: A model for 90Sr accumulation in human teeth formed by time of intakes

Samples of calcified tooth tissues (enamel, root and crown dentine) collected from the Techa riverside population exposed to radiation caused by radioactive releases from the nuclear weapon plant in South Ural were investigated. Accumulated absorbed dose in the samples was measured using the EPR-spectroscopy method. Beta activity of the samples containing radioactive 90Sr was measured by the method of low background anti-coincidence thin scintillating detection. High correlation between absorbed dose and beta activity was observed for enamel and root dentin but not for crown dentin. Otherwise, poor correlation was observed between absorbed doses as well as between beta activities for different tooth tissues of the same tooth. The results of dose measurement by EPR spectroscopy are analysed with the use of Monte Carlo simulation of dose formation due to 90Sr incorporated in tooth tissues taking into account biological elimination of 90Sr. Influence of 90Sr distribution in the tooth body on absorbed dose is discussed.