Radiation biodosimetry deals with the measurement of a biological response that serves as a surrogate for estimating the absorbed radiation dose in exposed humans. The biodosimetry methods include cytogenetic methods such as dicentric chromosomal assay (DCA), cytokinesis-block micronucleus assay (CBMN), Fluorescence in-situ hybridization (FISH) assay, Premature chromosome condensation (PCC), etc. All of them score the marking damages such dicentric chromosomes or centric rings to calculate the absorbed dose of ionizing radiation. As a part of the European union, Bulgarian radiobiology laboratories had to switch the direction of the mainly research activity to possibility for routine practice of analysis and diagnostic of the assessment dose after ionizing exposure. This possibility determines to use of more precise methods to diagnose cellular injuries accurately. For a short period of time Bulgarian laboratories had to choose method of analysis, to develop working protocols and their own calibration curves for them. The Research laboratory of Radiobiology and Radiation protection, Military Medical Academy-Sofia is in the process of integration of DCA as a main method of biodosimetry and CBMN as a supplementing method. The criteria to choose DCA as a main method is affordability and accuracy of the method. Next stage is to organize the whole process of integration as a routine diagnostic practice as additional source of information for the patients used by the clinical hematologists and oncologists. Aim of the study: The aim of the current study is to present and describe the selected biodosimetry methods, planned to be used in the Military Medical Academy-Sofia. Materials and methods:Dicentric chromosomal assay (DCA) and cytokinesis- block micronucleus assay (CBMN). Results: The review of the described methods, give the priority to the golden standard method (DCA). It is chosen as the most affordable, applicable and highly effective for the needs of the Scientific laboratory of Radiobiology and Radiation protection, Military Medical Academy-Sofia. Cytokinesis-block micronucleus assay (CBMN) is good supplementary method, but cannot be used as a main dosimetry method, because of its limitations. Conclusion: The biodosimetry assessment of the absorbed dose is a high skilled activity. It has involved team of professionals, correct selection of applicable methods and preliminary optimization of the process. Take into consideration of the advantages and disadvantages of the selected methods, the most affordable and effective method is DCA analysis.

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