Fig. 5From: Oral toxicological study of titanium dioxide nanoparticles with a crystallite diameter of 6 nm in ratsRepresentative images of histopathological examination in the 90-day study. A–F Yellowish brown materials found at the nasal cavity (A), trachea (B), lungs (C), cervical (D), and mediastinal (E) lymph nodes, and ileum (F) of male and female F344/DuCrlCrlj rats orally administered titanium dioxide for 90 days. Arrows indicate particles in the tissues. G Hypertrophy of mucous cells observed in the nasopharyngeal duct of the nasal cavity. Scale bar for A–F is 20 μm, and for G is 50 μmBack to article page