Lab to Emergency: Establishment and validation of automated method for rapid biodosimetry

Abstract

In inadvertent radiation exposure scenarios, accurate measurement of absorbed dose by biodosimetric techniques is crucial, especially when physical dosimetry is unavailable or in dispute. Chromosomal aberrations like dicentric (DC) and micronuclei (MN) are widely used for biodosimetry, with the former being the gold standard for individual dose assessment. However, both methods are labour-intensive requiring skilled analysis. This study aims to assess and compare the frequency and accuracy of DC and MN scoring through manual and automated methods. It investigates the establishment and validation of dose-response curves, in the dose range of 0-5 Gy, for 60Co-γ-ray-induced DC and MN using peripheral blood samples from three human volunteers. Statistical analysis confirmed dose-dependent increases in aberration frequencies, with Poisson distribution validation for all dose points. The manual and automated scoring methods yielded notable differences in linear and quadratic coefficients. Correlation analyses demonstrated substantial agreement between manual and automated scoring methods, particularly for MN (R2= 0.98). Towards validation, 16 dose-blinded samples were analysed for both endpoints using manual and automated scoring methods. Results yielded a close match between estimated and delivered doses, particularly evident with automated scoring (of both DC and MN) displaying superior accuracy for most of the doses. Notably, the variation was minimal, with -1.96% for DC and 2.85% for MN at 0.5 and 4 Gy, respectively. Automated scoring was approximately 15-20 times faster than manual scoring, suggestive of a faster practical option, especially in emergency scenarios such as criticality accidents and radiological emergencies, thus facilitating speedy triage and medical decisions.