Calculation and comparison of the direct and indirect DNA damage induced by low energy electrons using default and CPA100 cross section models within Geant4-DNA

Abstract

Interactions of ionizing radiations with cells could result in DNA base damage as well as SSB and DSB (single- and double-strand breaks). The mis-repaired damage can result in the cell death, genetic diseases, or cancer. Monte Carlo simulations allow us to determine the types of the DNA damage and their rates of occurrence. Here, we have employed the default Geant4-DNA and CPA100 cross section models (hereafter referred to as G4-DNA-default and G4-DNA-option6) for transporting electron beams of 0.011 – 100 keV through liquid water and hence simulating the physical and chemical interactions that are the reasons for potential direct and indirect damage to the DNA by electrons and hydroxyl radicals, respectively. Herewith, simple and complex SSB and DSB damage yields, frequency distributions of the direct and indirect damage, and the frequency of the deposited energies by electrons were evaluated and the results were compared with published experimental data and simulations. Overall, the G4-DNA-option6 results compare better with experiment than the results of G4-DNA-default.