Multinucleate Cells and Micronucleus Formation in Cultured Human Cells Exposed to 12 MeV Protons and γ-rays

Abstract

Cultured human cells of the EUE [human embryo] line were exposed to different doses of 12 MeV protons, plated and allowed to grow for 8 days; colonies were then scored for the presences of multinucleate cells and micronuclei. The frequency of both effects is an increasing function of the dose; the evaluated exponents of the dose-response equation (e = bDn) [e denotes relative frequency, d = dose] are n = 1.0 .+-. 0.1 for multinucleate cells and n = 1.6 .+-. 0.1 for micronuclei. By comparison with .gamma.-irradiations, RBE [relative biological effectiveness] values were obtained for both effects. The correlation between the log of the surviving fraction and the yield of the studied effects was statistically significant.