The effect of oxygen on the lung.

The harmful effect of oxygen in high concentration on the lung has been recognized for many years. Smith (1899) observed the lethal results following the exposure of experimental animals to oxygen at between 3 and 5 atmospheres pressure over a period of 24 hours. He considered that death resulted from pulmonary inflammation. Karsner (1916) and Binger, Faulkner, and Moore (1927) described widespread changes in the lungs of animals exposed to high concentrations of oxygen for 48 hours or more. Much of the early work was concerned with animals but later necropsy studies showed that similar pulmonary lesions occurred in man (Pratt, 1958). It was evident that oxygen could exert a harmful effect either over a short period at high pressure or over a longer time at atmospheric pressure.