EPR dosimetry among the population living in proximity to radioactive trace after the nuclear test on 29 August, 1949 at the Semipalatinsk nuclear test site

Electron-paramagnetic resonance retrospective dosimetry (EPR) with tooth enamel was used for measuring radiation dose in residents of Bodene and Dolon villages of Beskaragay rayon, Vostochno-Kazakhstanskaya oblast, Kazakhstan. The villages are located nearby the trace of radioactive fallout following the first nuclear test carried out on August 29, 1949 in the USSR. Fragments of 35 teeth extracted from adult residents of Bodene (26 fragments) and Dolon (9 fragments) due to medical reasons were used for EPR dosimetry. The village of Dolon is in the close proximity to the trace, the village of Bodene is located to the south-east of the Dolon village. In addition to that, fragments of 11 teeth of residents of the Kokpety village located 400 km to the east of the nuclear test site were used as well. The villagers were not exposed to radiation and represented a control group in the study. Because we could not obtain proper amount of the dental enamel from 35 teeth, samples of enamel from 29 teeth were used for dosimetry purposes. The highest radiation dose received by residents of Bodene and Dolon villages was found to be 313 mGy. Average accumulated external dose in examined residents with dental enamel formed before 1949 was 74 mGy. In people with enamel formed after 1949, when more than 95% of accumulated dose of external radiation had already been formed, average dose measured by EPR method was 11 mGy. The age at which dental enamel formation completed was determined in accordance with the IAEA Technical document (2002).