Studies of the responses to inhaled pollutant aerosols were made in rats with healthy lungs and with impaired lungs. Respirable aerosols were synthesized to resemble in composition those found in polluted air in California, alone and in combination with ozone. Comparative inhalation studies were also performed with an aerosol representing the famous London smogs of the 1950s, alone and in combination with sulphur dioxide. Neither aerosol by itself caused significant responses in healthy rats, but effects were observed in association with ozone exposure or lung impairment. In 30-day studies, there were increases in total lung DNA and protein content in rats exposed to the synthetic California-type aerosol compared to rats not so exposed. Small airway inflammation was also observed in animals exposed to ozone, an effect exacerbated by the inhalation of either type of aerosol and in animals with impaired lungs. There was no observed aerosol concentration dependence. In 3-day studies, there were increases of lung hydroxyproline (indicative of collagen synthesis and potential lung fibrosis) after exposure to the California-type aerosol, and to the London-type aerosol with SO2 after lung impairment. Both aerosols tended to decrease the rate of tracheobronchial clearance of deposited test particles. There was no change in alveolar permeability. Small airway fibrosis was caused by ozone, and this was aggravated by exposure to California-type aerosol.
|Original language||English (US)|
|Number of pages||8|
|Journal||Annals of Occupational Hygiene|
|State||Published - 1994|
ASJC Scopus subject areas
- Public Health, Environmental and Occupational Health