Acute Toxicity of Different Sized ZnO Nanoparticles in Mice after Intratracheal Administration

Acute toxicity of different sized (10, 30 and lOOnm) ZnO particles was investigated by intratracheal injection at the dose of 0.05 and 0.5g/kg body weight. The results of biochemical parameters assay, pathological examination and zinc accumulation showed main target organs for ZnO particles are demonstrated as lung, spleen, pancreas, bone and liver after exposure by intratracheal injection. But the toxic effects between different sized and dose ZnO particles are a little different. The toxicity of ZnO nanoparticles exhibited a dose-effect relationship. At low dose, three sized ZnO particles induce slight damage, and lOnm ZnO particles lead to relatively serious lung and liver damage. At high dose, 30nm ZnO particles result in worse lung, liver and pancreas injury. Furthermore, ZnO nanoparticles led to oxide stress, which may be an important reason for injury induced by ZnO particles.