Technical Report No. 8-87
Lethal and mutagenic effects of californium-252 radiation in cultured human cells
Ban S, Iida S, Awa AA, Sawada SSummary
HeLa MR cells were exposed to radiation emitted from a man-made spontaneously fissioning isotope, californium-252. The neutron (n) to gamma-ray ratio in the radiation dose was measured to be 2.0. The extrapolation number (n-value) of the dose-survival curve was 1.3, and the exponential slope (D0) was 200 cGy. A dose-dependent increase in mutation to 6-TGr was observed. The relative biological effectiveness (RBE) for cell killing of the neutrons from 252Cf, calculated relative to high dose rate X rays, was 2.6 at 50% survival. The RBE for mutation induction was 2.7 at a mutation frequency of 5 x 10-5 per surviving cell.
HeLa MR cells were exposed to radiation emitted from a man-made spontaneously fissioning isotope, californium-252. The neutron (n) to gamma-ray ratio in the radiation dose was measured to be 2.0. The extrapolation number (n-value) of the dose-survival curve was 1.3, and the exponential slope (D0) was 200 cGy. A dose-dependent increase in mutation to 6-TGr was observed. The relative biological effectiveness (RBE) for cell killing of the neutrons from 252Cf, calculated relative to high dose rate X rays, was 2.6 at 50% survival. The RBE for mutation induction was 2.7 at a mutation frequency of 5 x 10-5 per surviving cell.