Fig. 3

Examples of focal inflammatory cell infiltrates in livers of mice 28 days after intratracheal exposure to a single dose of vehicle control or NMs. Micrographs represent individual groups: A vehicle control, B ZnO 2 µg/animal, C CuO 6 µg/animal, D CuO 12 µg/animal, E Al₂O₃ 54 µg/animal, F SnO₂ 162 µg/animal, G TiO₂ 162 µg/animal, H Printex 90 162 µg/animal. Long arrows indicate a focal big inflammatory cell infiltration in A, C, D, F and G. Long thin arrows indicate a focal small inflammatory cell infiltration in B, D, E, F and H. Short thick arrows indicate necrotic hepatocytes in A, G and H. Short thin arrows indicate apoptotic bodies in focal inflammatory cell infiltrates in C, D and H. Ellipses indicate a local minimal increase of Kupffer cells in B and D. Asterisks indicate congestion in blood vessels in A, B, D and E. HE staining, magnifications were the same for all images as shown on image H