Dose-rate effect between 1 and 10 Gy/min in mammalian cell culture

Abstract
A dose-rate effect is observed between 1 and 10 Gy[grays]/min for cultured Chinese hamster V-79 fibroblast cells irradiated under PO2 [O2 partial pressure] levels of < 10 ppm, 100 ppm, 300 ppm and 21%. The dose for a cellular surviving fraction of 0.1% increases by 10-15% as the dose rate is changed from 10 to 1 Gy/min. This observed dose-rate effect is consistent with the repair of sublethal damage taking place during the radiation delivery. A related finding is that acute hypoxia in cell culture does not inhibit sublethal damage repair.
Keywords