Regular Article

Radiation dose–response curves: cell repair mechanisms vs. ion track overlapping^★

¹ Division of Physics and Chemistry, Faculty of Marine Engineering, Maritime University of Szczecin, Wały Chrobrego 1-2, 70-500 Szczecin, Poland
² Institute of Physics, University of Szczecin, Wielkopolska 15, 70-451 Szczecin, Poland
³ Joint Institute for Nuclear Research, Joliot-Curie 6, 141980 Dubna, Russia

^a e-mail: konrad.czerski@usz.edu.pl

Received: 5 January 2017
Received in final form: 24 September 2017
Published online: 19 December 2017

Abstract

Chromosome aberrations in human lymphocytes exposed to different doses of particle radiation: 150 MeV and spread out Bragg peak proton beams, 22 MeV/u boron beam and 199 V/u carbon beam were studied. For comparison, an experiment with ⁶⁰Co γ-rays was also performed. We investigated distributions of aberration frequency and the shape of dose–response curves for the total aberration yield as well as for exchange and non-exchange aberrations, separately. Applying the linear-quadratic model, we could derive a relation between the fitted parameters and the ion track radius which could explain experimentally observed curvature of the dose–response curves. The results compared with physical expectations clearly show that the biological effects of cell repair are much more important than the ion track overlapping.