The Deposition of Fibers and Spheres at the Carina in Excised Lungs.
NIOSH 1990 Sep:571-575
An investigation was conducted to comparative deposition of fibers and spheres at the carina in an effort to provide valuable insight into the deposition of fibers in the tracheobronchial system. Nearly monodispere, size classified glass spheres and glass fibers were prepared. Twenty nine pneumonia free calf lungs were obtained at the time of slaughter. The lungs were exposed for about 20 minutes to the prepared dust. The trachea was sliced into two sections for analysis of deposited particles. The authors conclude that this method for evaluating particle deposition at the carina in excised lungs can be used to investigate the influence of sedimentation, interception and diffusion on fiber removal. Altering the physical properties of the particles and/or the tracheal velocities should provide suitable conditions to derive empirical relationships defining the interplay of particle and airflow characteristics and removal efficiencies via these other deposition mechanisms. By choosing several large fiber sizes of equal impactive potential but of dramatically different length, the deposition enhancement by interception may be investigated.
Tissue-distribution; Body-burden; Airborne-dusts; Fibrous-bodies; Cell-damage; Dust-exposure; Silica-dusts; Lung-cells; Cell-function; Laboratory-animals; In-vitro-study;
Proceedings of the VIIth International Pneumoconioses Conference