Effects of Repeated Pulmonary Exposure to Carbon Nanotubes on Lung function

Objective The development of nanotechnology has increased the risk of exposure to types of particles other than combustion-derived ones in the environment, namely, industrial nanomaterials. However, their health impacts have not been fully elucidated yet. This study examined the effects of pulmonary exposure to two types of carbon nanotube (single-walled carbon nanotubes: SWCNT, and multi-walled carbon nanotube: MWCNT) on lung physiology in mice. Methods ICR mice were divided into three experimental groups to repeatedly administer vehicle, SWCNT (50 μg/animal), or MWCNT through intratracheal route; thereafter lung function was examined. Results The values of total respiratory system resistance (R: P<0.05), elastance (E), Newtonian resistance (Rn), tissue damping (G: P<0.05), and tissue elastance (H) were higher and the value of compliance (C) was lower in the SWCNT group than in the vehicle group. On the other hand, MWCNT tended to augment the values. Conclusions Taken together, CNT themselves inhaled, can impair airway function.