Further Studies on Chromosome Aberration Production after Whole-body Irradiation in Man

Summary

The dose–response curves for the production of chromosome aberrations in peripheral blood lymphocytes have been determined for radiation exposure both in vitro and in vivo. The in vitro response with 2 MeV x-rays follows approximately dose-squared kinetics over a range of 0–300 R. At low doses peripheral blood from an individual gives essentially the same results after irradiation in vivo and in vitro, but differences exist between individuals, though the response of blood cells from patients with cancer did not differ in this respect from controls. Extrapolation of in vivo data to doses higher than 50 R on the basis of the available in vitro data cannot yet be done with any certainty. More information is required on the shape of the in vivo dose–response curve, on the effect of the time after exposure at which the sample is taken and other possible factors that may cause variations.