A probabilistic model for intersubject deposition variability of inhaled particles.
Aerosol Sci Tech 1982; 1(4):355-362
A probabilistic lung model was proposed in which two random scaling factors are introduced to account for intersubject differences in deposition of inhaled particles in the human respiratory tract. Inhaled particles are deposited along the air passages in the head before entering the lung. The dynamics of particle motion in this region are very complex due to the passage geometry. Particle residence time is, however, relatively short. Deposition calculations were made in this model by considering the head as a random filter with different filtering characteristics at inspiration and expiration. The calculation was considerably simplified for deposition with mouth breathing as there is no deposition in the head during expiration. Excellent agreement was noted between the calculated deposition based on this model and data obtained from experimentation using 20 subjects in an earlier study. Experimental data was obtained using monodisperse di-2-ethylhexyl- sebacate particles at a controlled breathing condition of 800 cubic centimeter tidal volume, 4 second breathing period, with equal time for inspiration and expiration without pause. This finding supported the view that the major cause of intersubject deposition variability in various regions was difference in airway size.
NIOSH-Publication; NIOSH-Grant; Pulmonary-system-disorders; Inhalants; Aerosols; Chemical-deposition; Mathematical-models
Engineering Science S U N Y - at Buffalo Dept of Engineering Science Buffalo, N Y 14214
Aerosol Science and Technology
State University of New York at Buffalo, Buffalo, New York