Protein accumulation in lung lavage fluid following ozone exposure

Accumulation of protein in lung lavage fluid was used as an indicator of pulmonary damage following exposure of guinea pigs to O 3. Exposure of animals to 510, 1000, or 1960 μg/m 3 (0.26, 0.51, or 1.0 ppm) of O 3 for 72 hr resulted in significantly elevated levels of lavage fluid protein when compared to that of air controls. This effect was not observed in animals exposed to 196 μg O 3/m 3 (0.10 ppm). When exposure time was reduced to 3 hr, the O 3-induced protein accumulation in lavage fluids was undetectable unless the time of lavage was delayed 10–15 hr following the exposure. Under these conditions, elevated protein content was seen in lung lavage fluids obtained from animals exposed to O 3 ranging from 510 to 1470 μg O 3/m 3 (0.26-0.75 ppm) and a dose relationship between the amount of protein accumulation in the lung and the concentration of O 3 to which the animals were exposed was observed. Vitamin C deficiency did not enhance this O 3-induced lesion in guinea pigs. The dose relationship has also been confirmed by polyacrylamide gel electrophoresis of the lavage fluids. Lung lavage fluid protein content in animals exposed to 353 μg O 3/m 3 (0.18 ppm) for 8 hr/day for 5 or 10 consecutive days was not different from that of air controls.