Effects of single thoracic x-ray exposure in rats

Pathophysiologic changes in female and male rats after exposures to single doses of thoracic x-irradiation of 0, 600, 1200, 2400, or 3600 rad, are reported and discussed. The dose of 3600 rad caused death associated with a starvation-like effect during 1-4 weeks postexposure period, attributable largely to severe esophageal damage. The dose of 2400 rad permitted longer survival than that at 3600 rad and death was associated chiefly with lung fibrosis. The mortality of rats after doses in the range of 1200 or 600 rad roughly paralleled that of the control group and showed no special modal death times or special causes of death. Differences in responses between sexes were slight.