Killing and mutation of Chinese hamster V79 cells exposed to accelerated oxygen and neon ions.

Mutation induction by accelerated heavy ions to 6-thioguanine resistance (HPRT system) in Chinese hamster V79 cells was investigated using oxygen and neon ions with energies between 1.9 and 400 MeV/mu, corresponding to LET values between 18 and 754 keV/microns, respectively. Because of technical limitations most experiments could be performed only once. Inactivation and mutation induction cross sections, sigma i and sigma m, were obtained from the slopes of the exponential survival and the linear mutation induction curves, respectively. Both parameters increased with LET up to about 200 keV/microns, where the curves separated for the two types of ions. Calculated RBEs were higher for mutation induction than for killing for all LET values.