Cytogenetic analysis of 60Co γ-radiation-induced chromosome damage and simulations using the Geant4 Monte Carlo toolkit

The study involves the determination and quantization of radiation damage on a cellular level and the replication of this energy deposition using the Geant4 Monte Carlo toolkit, developed for particle transportation simulations at CERN. The detection of micronuclei in binucleated cells was used to analyse the effects of the radiation. Results from micronucleus assays of rat brain endothelial and Chinese hamster ovary cells that have been irradiated with gamma rays, produced by a Co-60 teletherapy unit at iThemba LABS, are presented. Linear-quadratic dose response curves were determined for both cell lines. The simulated results of the Co-60 setup, irradiation and other relevant features offered by the Geant4 toolkit are also discussed. Finally, prospective microdosimetric studies and simulations of damage caused by DNA-incorporated I-123 will be mentioned.