Exposure-effect relationship of selected pulmonary function measurements in subjects exposed to ozone

Summary Healthy adult male volunteer subjects were exposed to 0.15, 0.3, 0.45 and 0.5 ppm ozone (O₃) with and without intermittent light exercise. The results suggest that the subject's level of exercise during exposure is considerably related to the magnitude of changes in lung function and the occurrence rate of respiratory symptoms at any given O₃ concentration, and that among healthy subjects there is a considerable range of reactivity to O₃ exposure. A level of 0.15 ppm O₃ with intermittent light exercise produced a significant decrease of specific airway conductance in most subjects and coughing during deep inspiration in five of 15 subjects, while a level of 0.5 ppm O₃ produced fewer effects when the subject did not exercise. The nonsmoker is more reactive to O₃ than the smoker. The subject's level of exercise during exposure and his smoking habit are two important factors in evaluating the exposure-effect relationship of O₃.