Fig. 8

Histological findings at 3 days following the instillation. A distilled water as a negative control, B 0.2 mg CL-PAA-exposed lung, C 1.0 mg CL-PAA-exposed lung, D 1.0 mg crystalline silica-exposed lung, E 1.0 mg asbestos (chrysotile)-exposed lung, F 1.0 mg NiO nanoparticle-exposed lung, G 1.0 mg CeO₂ nanoparticle-exposed lung. These are all HE stained specimens. There were inflammatory cells, mainly neutrophils (red arrow heads) and macrophages (black arrow heads), in the alveolar space in the exposed groups. Inflammatory cell infiltration was more pronounced in a dose dependent-manner, especially in the CL-PAA exposed groups, compared to in the other exposed groups (internal scale bar = 250 μm for all)