Fig. 6

Histopathology of hematoxylin and eosin-stained mouse lung sections after exposure to U-MWCNTs or Z-MWCNTs at one and 28 days post-exposure. Treatment with U-MWCNTs caused more focal, condensed lesions at alveolar duct bifurcations (ADB) at day one (arrows) whereas Z-MWCNTs caused a more diffuse inflammatory response in the lower lung around terminal bronchioles (TB), ADB and alveolar ducts (AD). At day 28, both U-MWCNTs and Z-MWCNTs caused focal lesions at ADB (arrows). (*) indicate sites of inflammation