PULMONARY-FUNCTION AND MAXIMUM EXERCISE RESPONSES FOLLOWING ACUTE OZONE EXPOSURE

  • 1 January 1979
    • journal article
    • research article
    • Vol. 50  (9) , 901-905
Abstract
Changes in pulmonary function during resting exposure to concentrations of O3 at 0.75, 0.50, 0.25 and 0.00 ppm were examined and the effect these exposures had on a subsequent maximum exercise test using filtered air was determined. To determine if recovery of pulmonary function would be facilitated by increased ventilation due to maximum exercise, a control condition was conducted with subjects resting for a period equivalent to the maximum exercise condition. Eight males and 5 females participated in 8 different conditions. Resting 2 h exposure to 0.75 and 0.50 ppm O3 caused significant decrements in forced vital capacity of 10% and 5%, respectively. However, 0.00 and 0.25 ppm O3 induced no pulmonary decrement. None of the pollutant conditions reduced subsequent maximum exercise performance (ml O2/min per kg, heart rate and total performance time). The pulmonary function responses after the maximum capacity test returned to pre-O3 values for the 0.50 ppm condition, but were still significantly decreased for the 0.75 ppm condition. The increased ventilatory exchanges from maximum exercise did not facilitate the return of pulmonary function. Increased ventilation during ozone exposure apparently plays a significant role only in inducing pulmonary function decrement, but not in facilitating the return of pulmonary function to normal values.