Experimental Study of Fibrosis Effect of Polypropylene and Polyethylene Dust on Rat Lungs.
Liu-Z; Fang-Y; Yie-F; Xiao-C
NIOSH 1990 Nov:840-844
The fibrogenicity of polypropylene (9003070) and polyethylene (9002884) dusts was studied in rats. Wistar-rats were administered 50 milligrams polypropylene, polyethylene, or quartz (14808607) dust intratracheally. Selected rats were killed 1, 6, 12, or 18 months later and the lungs and hilar lymph nodes were removed. The extent of fibrosis was determined by measuring the amount of collagen in the right lung and examining the left lung and lymph nodes for histopathological changes. Polyethylene and polypropylene caused slight granulomatous changes in the lungs 1 to 6 months after exposure. The changes became more pronounced after 12 to 18 months with the granulomas impinging on the bronchial walls. Interstitial tissue hyperplasia was also seen. The hilar lymph nodes were slightly enlarged. Lung collagen concentrations increased sharply at 12 months. The collagen concentrations in polypropylene exposed rats decreased thereafter, but continued to increase in polyethylene exposed rats. Quartz caused a progressive fibrosis. The hilar lymph nodes were enlarged and developed fibrous tuberculi by 6 months. Lung collagen concentrations increased during the first 12 months post exposure, tapering off thereafter. The authors conclude that polyethylene and polypropylene have a slight fibrogenic effect in rats.
In-vivo-studies; Laboratory-animals; Organic-dusts; Petroleum-products; Polymers; Silica-dusts; Inhalation-studies; Proteins; Lung-fibrosis; Histopathology; Lymph-nodes;
9003-07-0; 9002-88-4; 14808-60-7;
Proceedings of the VIIth International Pneumoconioses Conference