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C J Setzer

Publications and source records attributed to C J Setzer.

3 recordsLinked to original sources

Inhalation studies of Mt. St. Helens volcanic ash in animals: respiratory mechanics, airway reactivity and deposition.

Effects of fine volcanic ash aerosol on pulmonary mechanical properties of awake guinea pigs were evaluated during exposure by inhalation. Ash penetration into the lung as well as tissue response to ash were determined by transmission electron microscopy. The reactivity of airway epithelial irritant receptors following ash exposure was assessed using a histamine bronchoprovocation test. Results indicated that breathing 9,4 mg/m3 of ash for 2 hr did not cause a measurable change in pulmonary function of guinea pigs. Electron micrographs showed that ash particles in the lung below the hilus did not seem to produce any acute tissue reaction and were almost all phagocytized by macrophages. Airways of guinea pigs exposed to ash were significantly less responsive to histamine than were the airways of animals exposed only to air. It appears that even though Mt. St. Helens ash was well tolerated by the guinea pig during the exposure, its presence in the inhaled air did change the "histamine sensitivity" of airway epithelial irritant receptors.

Air Pollutants↗

Effects of prenatal nitrofen exposure on postnatal lung function in the rat.

The herbicide Nitrofen was administered by gavage to pregnant F-344 rats during Days 10 through 13 of gestation. Postnatal lung function was measured in male progeny at 3 and 6 weeks of age. There were no differences in body weight or wet and dry lung weights between control and Nitrofen-exposed rats in either age group. Nitrofen produced no observable effects on lung function at 3 weeks of age. However, by 6 weeks of age the Nitrofen-exposed animals had significant decreases in tidal volume (p less than 0.01), vital capacity (p less than 0.01), total lung capacity (p less than 0.05), and quasi-static lung compliance (p less than 0.01). There was also a mild ventilation inhomogeneity, as indicated by significant increases in the nitrogen washout slope (p less than 0.01) and the moment ratio (p less than 0.05). Histopathology of lung, liver, kidney, and testes was not significantly altered by Nitrofen exposure. These data suggest that prenatal Nitrofen exposure may have an effect on postnatal lung maturation in the rat and could potentially be useful as a model of pulmonary hypoplasia.

Aging↗