Effects of sulfate aerosols in combination with ozone on elimination of tracer particles inhaled by rats

Effects of pollutant atmospheres on surface receptors of pulmonary macrophages

“…Studies with diesel exhaust and acids using the same concentrations and exposure regimen described here did not alter early (50 h, mucociliary) or late (30 d, alveolar) clearance of insoluble inhaled polystyrene latex microspheres studied as described by Phalen et al (1980) and others (Kenoyer et al, 1981;Mannix et al, 1983). This atmosphere also failed to induce histologic or autoradiographic abnormalities in nasal or pulmonary airway epithelial or in the alveolar zone of exposed rat lungs (unpublished).…”

Effects of Repeated Exposure to Nitric Acid Vapor and Ozone on Respiratory Tract Clearance in the Rat

“…Acute, 4-h exposures of rats t o 0.8 p p m 0, have been found t o delay early respiratory tract clearance, and accelerate late clearance (Phalen et al, 1980;Kenoyer et al, 1981). However, Schlesinger et al (1992b) o f 3 5 0 pg/m3 HNO, vapor and 150 pg/m Y H, SO, aerosol.…”

“…The distal airways and alveolar epithelial cells have been described as principal targets of oxidant pollutants (including o,) (Warheit, 1989). But effects of acute exposure to 0, on mucociliary (upper respiratory tract) clearance have also been observed (Frager et al, 1979;Phalen et al, 1980;Kenoyer et al, 1981), and morphological examinations have identified ciliated cells in the large airways as targets of 0, damage (Schwartz et al, 1974;Frager et al, 1979). In this study, the concentrations of 0, and HNO, were o n the order of environmentally realistic levels; thus, the findings have relevance to community exposures.…”

“…This decision was based on computations performed to ensure that the probability of a type 2 error (the error i n accepting a false n u l l hypothesis) i s maintained at a tolerable level, and so that the study could be conducted w i t h a manageable number of animals. The results of our prior clearance studies that have been published (Phalen et al, 1980;Kenoyer et al, 1981;Frager et al, 1979;Mannix et al, 1982Mannix et al, , 1983Mannix et al, , 1991Prasad et al, 1990) have been tested based on t h e p < . l criterion.…”

“…Prior to this study a manpower-intensive rat clearance protocol had been followed (Phalen et al, 1975(Phalen et al, , 1980Kenoyer et al, 1981;Mannix et al, 1982Mannix et al, , 1983Prasad et al, 1990). An examination of data from these prior studies indicated that nearly the same degree of information concerning the effects of pollutant atmospheres on clearance could be obtained using a simpler protocol.…”