Histopathological cross sections showing light microscopy of spleen in mice treated with atrazine (2-chloro-4-ethytlamino-6-isopropylamine-1,3,5-triazine; ATR) (hematoxylin and eosin (H&E) stain, magnification ×10). (a) Control group. The histological structure is normal. (b) The 200 mg/kg ATR group. Atrophic and effaced splenic germinal centers, the diminution of white pulp (filled triangles) and congestion of red pulp (arrow) in the spleen can be seen. (c) The 400 mg/kg ATR group. Effaced splenic germinal centers and the diminution of white pulp (filled triangles), associated with obvious congestion in red pulp (arrow).