Fig. 2.

Lungs of rats 3 days after exposure showing severe emphysema (a) and hemorrhage (a–1) in the ⁵⁶Mn internally exposed group (0.1 Gy), but no pathological changes in the ⁶⁰Co γ rays (2 Gy) externally exposed (b) and unexposed control groups (c). As with the control, experiments with a stable Mn group were also conducted, and no change was observed. Hematoxylin and eosin (H&E) staining, original magnification ×10. (a, a-1, c from [23]/CC BY 4.0).