In the present study, an aerosol of multi-walled carbon nanotubes (MWCNT) was produced with an acoustical generator, and airborne concentration and size distribution was determined. Mice were exposed by whole body inhalation to MWCNT (5 mg/m3, 5 hours/day, 12 days) and pulmonary responses were monitored at 1 day, 2, 4, 12, 24 and 48 weeks post-exposure. Pulmonary responses were investigated using whole lung lavage, histopathology, morphometry, and enhanced darkfield light microscopy studies. MWCNT lung burden was also measured to assess MWCNT clearance. Data indicate that the lung burdens of MWCNT in this study represent lung burdens relevant to estimated human occupational exposures and caused time-dependent pulmonary inflammation, damage and pulmonary fibrosis. Using enhanced darkfield microscopy, MWCNT fibers were found in lavage of the pleural space, parietal pleura, and respiratory muscles of the diaphragm and chest wall. The time course of pulmonary responses and their relationship to MWCNT lung burden and clearance will be discussed.
Toxicology; Nanotechnology; Aerosols; Laboratory-animals; Laboratory-techniques; Exposure-assessment; Exposure-levels; Inhalation-studies; Pulmonary-function; Pulmonary-system; Lung-function; Dose-response; Histopathology; Lung-burden; Microscopy; Pulmonary-disorders; Lung-fibrosis; Lung-irritants; Fiber-deposition; Pleural-cavity
The Toxicologist. Society of Toxicology 52nd Annual Meeting and ToxExpo, March 10-14, 2013, San Antonio, Texas