Effect of diesel emissions and coal dust inhalation on heart and pulmonary arteries of rats.
Vallyathan-V; Virmani-R; Rochlani-S; Green-FH; Lewis-T
J Toxicol Environ Health 1986 Sep; 19(1):33-41
Long term effects of exposure to coal dust (CD), diesel emissions (DE), and a combination of the two (CD plus DE) were examined on the pulmonary arteries and hearts of Fischer-344-rats. The animals were exposed for 7 hours/day, 5 days/week for 24 months. Heart and body weights and the ratio of heart weight to body weight were not significantly different in the exposed groups compared to controls. Pathologic effects were seen in the lungs of all exposed animals, and were characterized by focal accumulations of particle laden alveolar macrophages in alveoli adjacent to alveolar ducts, and associated with mild type-II cell hyperplasia of the alveolar lining cells. These changes were most evident in rats exposed to DE only. There was no evidence of significant fibrosis, although pigmented macrophages were noted in the interstitium. No significant differences in distribution of pulmonary artery categories were noted among the exposed groups. The greatest increase in medial wall thickness was noted in DE exposed animals, as compared to other groups in all three arterial size categories. In none of these categories did this difference reach statistical significance. The authors conclude that exposure to low levels of DE and CD separately or in combination did not produce any significant effects on the hearts or pulmonary arteries of Fischer-344-rats. However, DE exposed rats did exhibit increased thickness of pulmonary artery walls. No evidence was found for additive or synergistic effects of DE with CD.
NIOSH-Author; Diesel-engines; Diesel-emissions; Diesel-exhausts; Laboratory-animals; Mine-workers; Mining-industry; Lung-disorders; Inhalants
Journal of Toxicology and Environmental Health