Unilateral Pulmonary Function Study of Ozone Toxicity in Rabbits

In a unilateral pulmonary function study, Flemish giant rabbits breathing 12 ± 1 ppm ozone in the left lung exhibited an initial bilateral increase in respiratory rate and minute volume as well as a bilateral decrease in tidal volume and dynamic compliance. Pulmonary function parameters were not statistically different for ozone- and ambient-airtreated lungs until pulmonary edema developed in the lung exposed to ozone, as evidenced by a percent increase in the wet weight of that lung. Tidal and minute volumes, inspiratory and expiratory flows, and dynamic compliance decreased and pulmonary flow resistance increased in the lung exposed to ozone. Because pulmonary edema preceded significant functional changes, the former is considered a more sensitive indicator of the extent of ozone toxicity. Edema occurred only in the lung breathing ozone.