Experimental studies of the total deposition of aerosol particles in the human respiratory tract.

The deposition in the human respiratory tract of monodisperse airborne di-2-ethylhexyl sebacate (DES) droplets in the size range from 0.2 to 1 μm dia, was studied for a 500 cm 3 tidal volume and a 4 sec breathing cycle without respiratory pauses. Four male subjects served as volunteers in the breathing experiments. The calculation of deposition was based upon measurements of the number concentration of the aerosol particles and the respiratory flow rate at the mouth. No particle size of minimum deposition and no differences in the average deposition of the subjects was found provided the inhalations were initiated from the subjects' normal functional residual capacities. The deposition in the above particle size range was found to be about 0.1