The Fibrosis and Other Morphologic Changes of Rat Lung Caused by Intratracheal Injection of Different Sizes of Metallic Aluminum Dusts.
NIOSH 1990 Nov:1167-1171
Results were presented of an investigation that examined the biological effects of different sizes of metallic aluminum (7429905) dusts in male Wistar-rats. The dusts were obtained from an aluminum company which manufactured aluminum powders with different sizes. The chemical composition of the aluminum particulates was 96% aluminum, 3% alumina, and 0.3% ferric-oxides. No toxic heavy metals were detected. Each group of rats was intratracheally injected respectively with 1.0 milliliter of 1, 5, 10, or 15 micrometers aluminum dust suspension or saline. The rats were sacrificed 6 to 9 months after injection. The strongest fibrogenic size was below 5 micrometers. After 6 or 9 months of intratracheal injection of 50 milligrams of dust, the 5 and 1 micrometer dusts were more fibrogenic than the 10 micrometer or 15 micrometer dusts. Grade-III and even grade-IV lung nodular fibrosis, intensive staining of collagen fiber in alveolar wall, and higher collagen contents were caused by the 1 and 5 micrometer sizes. Of the 1 and 5 micrometer size, the 5 micrometer dust was more fibrogenic. Significant alveolar wall thickening and slight emphysema were produced by the 10 micrometer aluminum dust.
Laboratory-animals; In-vivo-study; Mineral-dusts; Dust-inhalation; Coal-dust; Silica-dusts; Lung-burden; Lung-cancer; Respiratory-system-disorders;
Asthma and Chronic Obstructive Pulmonary Disease; Disease and Injury; Respiratory-system-disorders;
Proceedings of the VIIth International Pneumoconioses Conference