The Estimation of the Nonrecuperable Injury Caused by Ionizing Radiation

Abstract

Exposure of mice to a non-lethal treatment of X-rays (2 to 5 doses of 300 r at intervals of 3 weeks) reduced the LD50 for X-rays of the mice. The amount by which the LD50 is reduced, called the nonrecuperable injury, is proportional to the total amount of radiation in the non-lethal course. The non-lethal course of X-ray does not change either the mechanism of acute death from X-ray or the distribution of sensitivity to X-ray. The nonrecuperable injury does not account for the observed mortality of animals from chronically imposed radiation.