Estimation of Absorbed Doses on the Basis of Cytogenetic Methods

Long-term studies in the field of radiation cytogenetics have resulted in the discovery of relationship between induction of chromosome aberrations and the type of ionizing radiation, their intensity and dose. This has served as a basis of biological dosimetry as an area of application of the revealed relationship, and has been used in the practice to estimate absorbed doses in people exposed to emergency irradiation [1,2]. The necessity of using the methods of biological dosimetry became most pressing in connection with the Chernobyl accident in 1986, as well as in connection with other radiation situations that occurred in nuclear industry of the former USSR. The materials presented in our works [3-8] demonstrate the possibility of applying cytogenetic methods for assessing absorbed doses in populations of different regions exposed to radiation as a result of accidents at nuclear facilities (Chernobyl, the village Muslyumovo on the Techa river, the Three Mile Island nuclear power station in the USA where an accident occurred in 1979). Fundamentally, new possibilities for retrospective dose assessment are provided by the FISH-method that permits the assessment of absorbed doses after several decades since the exposure occurred [7]. In addition, the application of this method makes it possible to restore the dynamics of unstable chromosome aberrations (dicentrics and centric rings), which is important for further improvement of the method of biological dosimetry based on the analysis of unstable chromosome aberrations [9]. The purpose of our presentation is a brief description of the cytogenetic methods used in biological dosimetry, consideration of statistical methods of data analysis and a description of concrete examples of their application.