Exposure-response relationship of bronchial mucociliary clearance in rabbits following acute inhalations of sulfuric acid mist.

Eight rabbits underwent 1 h oral inhalations of submicrometer sulfuric acid mist at concentrations ranging from approx. 100-1084 micrograms/m3, followed by measurement of the mucociliary clearance of a tracer aerosol from the bronchial tree. These data, plus those from a previous study, were used to construct an exposure concentration-response relationship for alterations in clearance produced by H2SO4. The response pattern is characterized by transient acceleration of clearance at low concentration exposures, and retardation at higher concentrations. In addition, comparison of these results with those from a similar study using human volunteers supports use of the rabbit as an appropriate model for studying mucociliary clearance alterations produced by inhaled irritants.