[Modeled Deposition of Fine Particles in Human Airway in Northern Suburb of Nanjing]

The particles number concentrations were determined by Wide-range Particle Spectrometer (WPS) in northern suburb of Nanjing in January and April 2015. The information of size distributions was applied in the multiple-path particle dosimetry model (MPPD) v.3.04 to quantify deposition fractions (DF) and number concentration (NC) depositions of fine particles in different regions of human airway, at different air quality levels, at rest and exercise. DF of nucleation mode and Aitken mode at rest and exercise were similar, while DF of accumulation mode at exercise was 2.49 times of that at rest. DF of nucleation mode and Aitken mode in pulmonary (PUL) was the highest, about 48.17% of total deposition fractions (TDF) at rest and 54.23% of TDF at exercise. DF of accumulation mode in head was the highest, about 41.23% of TDF at rest and 80.47% of TDF at exercise. The particle NC deposition in human airway in winter was lower than that in spring, and the total NC deposition in 3 regions was in the order of PUL > tracheobronchial(TB) > head. Compared with resting, nucleation mode deposition in PUL and accumulation mode deposition in TB and head increased at exercise. The worse the air quality, the higher the deposition growth rate of exercising to resting in head. DF difference among regions was mainly due to the different physiological parameters, while NC deposition difference was mainly due to the different particle NC in the local environment.