Determination of total ionizing radiation doze on animals from west Kazakhstan by EPR method

Abstract

A wide application in industry and medicine of ionizing radiation sources, and a possibility of accidents at nuclear power stations led to a development of dosimetry techniques, allowing one to determine the dose of various samples. Tooth and bone EPR dosimetry is now one of the most powerful methods of retrospective and accident dosimetry. Tooth enamel electron paramagnetic resonance (EPR) dosimetry is of a significant practical interest due to the possibility of use of human and animal teeth as individual dosimeters. Electron paramagnetic resonance was applied for a long time as a tool to study radiation effects. Under ionizing irradiation unpaired electrons in materials are produced, the concentration being dependent on the absorbed dose, therefore the latter can be determined from EPR spectrum of the sample. Radiation induced center' lifetime in solid specimens (minerals, mollusk shells, bones, teeth, ets.) is long enough. It allows one to determine with a high accuracy the total dose absorbed by the sample using the signal intensity of radiation induced unpaired electrons. The advantages pertinent to EPR in comparison with other dosimetry methods (e.g. thermoluminescence, or spectrophotometry) are the possibility of nondestructive analysis, quantitative dose evaluation, and high sensitivity and large dynamic range of dose evaluation. The most important is retrospective dosimetry for dose evaluation of inhabitants of radionuclide soiled regions. In such cases any available data concerning the extent of radiation effect on inhabitants are necessary to determine urgent medical and organizing activity aimed at elimination of the pathogenic irradiation effect.