Prof. Eric Gregoire

Abstract

Principles and added-value of the Biodosimetry in individual dose reconstruction arsenal and human radioprotection after radiation exposure.

Eric Gregoire

Institut de Radioprtection et de Sureté Nucléaire, Fontenay-aux Roses, France

E-mail : eric.gregoire@irsn.fr

Abstract :

Tools for radiation exposure reconstruction are required to support the medical management of radiation victims in radiological or nuclear incidents. Different biological and physical dosimetry assays can be used for various exposure scenarios to estimate the dose of ionizing radiation an individual has absorbed. The knowledge of the dose is a major concern as it allows medical doctors to diagnose the lesion in order to treat it. Biological dosimetry refers to the measurement of biological parameters affected by ionizing radiation. The techniques that can be performed in case of dose reconstruction will be exposed with their advantages and limits. The cytogenetic techniques based on the scoring of chromosomal aberrations as biomarkers generated by radio-induced DNA-damage are the following: Dicentric chromosome assay (DCA – used in dose reconstruction at IRSN), Fluorescence in situ hybridization assay (FISH, used for older radiation exposures), cytokinesis-block micronucleus assay (CBMN, another method faster than DCA) and premature chromosome condensation assay (PCC). Other techniques are in development in biological dosimetry, such as the gH2AX assay (used as a biomarker of repair) and gene expression profiles. In our laboratory we focus on DCA, which is the gold standard technique used in biological dosimetry. This is the main technique used in biological dosimetry since the 1940’s. In order to show the power of DCA, different exposure accidents analyzed at IRSN will be presented. Finally, the perspectives of new approaches for biological dosimetry will be discussed.

Key words: Biological dosimetry, dose reconstruction, dicentric chromosome, chromosomal aberrations, cytogenetic techniques, DNA damage, human radioprotection, accidental radiation exposure.