Experimental investigation on the relative importance of mucosal exposure and inhalation exposure to airborne particles

摘要

Occupational health and safety have long been a global concern, especially for developing countries. Airborne particles are considered as the main threatening factors. The harm of airborne particles come from inhalation exposure and mucosal exposure, separately. Identifying relative importance of these two exposure risks provide possibility to realize better individual protection. There are seldom progress on simultaneous assessment of the particles deposited on facial mucosa and the particles inhaled into the lower airway. We developed an in-vitro respiratory system from a healthy volunteer by CT-imaging and 3D printing, and the replica of facial details was added for this study. Monodispersed florescent particles with the aerodynamic diameters dae of 0.6-5 um were generated by TSI VOAG 3450® and monitored by TSI APS 3321®. The lower airway exposure was measured as the total accumulative particles that enters the lung volumes during the sampling period. SKC BioSampler® was used for collecting the suspended fluorescent particles in the lung volumes, while preset foils were used to sample the particles deposited on the surface of the lung volumes and face mucosas. Results shown that 0.6-2.0 pm particles that reach the lower airway can be 10 times as many as the total particles deposited on eyes and lips during the same exposure period. 5 pm particles, on the contrary, mainly cause mucosal exposure, 90% of which were deposited on the lips. The results prepare a solid input for further dose-response measurements with in-vitro cells.