Acute ozone exposure increases plasma prostaglandin F2 alpha in ozone-sensitive human subjects

Twenty O3-sensitive and 2O O3-nonsensitive subjects participated in a study to investigate the effects of disparate O3 sensitivity on plasma prostaglandin F2 alpha) responses consequent to exposure to ambient O3 concentrations. Subjects were selected from a pool of 75 normal healthy college-aged males who had been previously exposed to 0.35 ppm O3 for 1 h at an exercising VE of 60 L/min. The selection criterion used was the observed decrement in FEV1 after the O3 exposure: O3-sensitive, FEV1 decrement greater than 24%; O3-nonsensitive, FEV1 decrement less than 11%. Each subject was exposed to filtered air and to 0.20 and 0.35 ppm O3 for 80 min while exercising at a VE of 50 L/min. These experimental protocols were divided into two 40-min sessions separated by a period of 4 to 10 min. PGF2 alpha, FVC, FEV1, and FEF25-75 were evaluated before, during, and after each protocol. SGaw and Vtg were measured before and after each protocol. Plasma PGF2 alpha was significantly increased in the O3-sensitive group during and after the 0.35-ppm O3 exposure.