Diffusional deposition of ultrafine particles in the human lung.
Aerosols in the mining and industrial work environments, Vol. 1, fundamentals and status. Marple VA, Liu BYH, eds. Ann Arbor, MI: Ann Arbor Science, 1983 Jan; 1:139-149
The diffusional deposition of ultrafine particles was investigated in the human lung during steady breathing and breath holding. A deposition model was used as the basis of the study and treated the airways as a 1 dimensional time dependent distributed system in which the airway depth was used as the spatial variable. The deposition formulas for a single airway adopted in this study corresponded to two idealized flow patterns; one for slug flow, the other for parabolic flow. Deposition calculations from the model showed that under normal breathing conditions, diffusion alone accounted for more than 99 percent of total deposition produced by the combined effects of diffusion, sedimentation, and impaction for particles with a diameter smaller than 0.1 micrometer (microm). The calculated deposition of 0.2microm particles agreed with the experimental data of previous researchers. Lung volume had a weak effect on tracheobronchial deposition; however large deposition differences were found in the pulmonary region. In the breath holding experiments, diffusional particles were more effective than inhaled particles in measuring the size of air spaces in the lung. Diffusional deposition was more sensitive to airway size than was sedimentational deposition. Ultrafine particles were better tools for measuring airway dimensions.
NIOSH-Grant; Aerosols; Lung; Inhalants; Lung-cells; Air-purification; Humans; Air-contamination; Aerosol-particles; Analytical-models; Lung-burden; Analytical-instruments; Nanotechnology
Engineering Science S U N Y - at Buffalo Dept of Engineering Science Buffalo, N Y 14214
Aerosols in the mining and industrial work environments, Vol. 1, fundamentals and status
State University of New York at Buffalo, Buffalo, New York