Correspondence

Abstract

There is currently a controversy in the literature about the shape of the survival curves obtained by irradiating cells in vitro under hypoxic conditions (Elkind, Alescio, Swain, Moses and Sutton, 1964; Hall, Bedford and Oliver, 1966; Revesz and Littbrand, 1964). Since hypoxia is usually produced by flushing a container with nitrogen or argon, it might be argued that differences in the concentration of oxygen in the flushing gas at the time of irradiation are responsible for varying degrees of hypoxia in the cells and therefore for the different shapes of the survival curves.