Morphology and Morphometry of the Lung in Cynomolgus Monkeys after 2 Years Inhalation of Quartz under Normal and Excess Pressure.
Rosenbruch-M; Koruros-M; Krombach-F
NIOSH 1990 Sep:530-534
The morphological results were provided of an inhalation experiment carried out in cynomolgus-monkeys with quartz (14808607) dust and compressed air. The monkeys were divided in four groups: group-I was exposed to normal atmospheric pressure without dust; group-II was exposed to quartz dust at 5mg/m3 and normal pressure; group-III was exposed to quartz dust at 5mg/m3 with 2.5 bar absolute pressure; and group-IV was exposed to 2.5 bar absolute pressure without dust. Exposures lasted for 26 months and covered 5 days per week for 8 hours each day. Animals were sacrificed immediately after the last exposure. There appeared to be a delay in the formation of silica induced granulomas in animals subjected to dust and excess pressure. Pathogenically the results described developed in the following manner: the clearance of inhaled particles from the lung first occurred via bronchi and trachea and second via regional lymph nodes. The lymph nodes were overflowing and in this way macrophages with phagocytized particles reached the blood and were deposited in other tissues such as the liver, spleen and mesenteral lymph nodes. Heart weights in group-IV animals were increased compared with group- I animals, indicating that excess pressure caused effects on the respiratory and circulatory system.
Inhalation-studies; Respiratory-system-disorders; Lung-disease; Pulmonary-disorders; Lung-function; Dust-exposure; Laboratory-animals;
Asthma and Chronic Obstructive Pulmonary Disease; Disease and Injury; Respiratory-system-disorders;
Proceedings of the VIIth International Pneumoconioses Conference