Acute toxicity of ferric oxide and zinc oxide nanoparticles in rats.

We investigated the toxic effects of inhalation exposure to ferric oxide (Fe2O3) and zinc oxide (ZnO) nanoparticles in rats. Male Wistar rats were consecutively treated with Fe22O3 at 8.5 mg/kg body weight and ZnO nanoparticles at 2.5 mg/kg body weight, twice daily for 3 days. Content of Fe2O3 and ZnO in tissues, biochemical parameters in serum, and hispathological examinations were analyzed at 12 h and 36 h after the 3 day treatment. In the Fe2O3-treated group, iron (Fe) content in liver and lung tissues was significantly increased at 36 h. In the ZnO-treated group, zinc (Zn) content in liver tissues was significantly increased at 12 h and further increased at 36 h. The levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total protein (TP), creatine kinase (CK), and lactate dehydrogenase (LDH) in both nanoparticle-exposed groups were significantly decreased compared to the unexposed controls. Histopathological examination showed that both types of nanoparticles caused severe damage in liver and lung tissues. Although this damage progressed in both liver and lung throughout the postexposure period, no significant elevation of serum enzyme activities was observed in response to either nanoparticle type.