Zinc oxide (ZnO) is the most commonly used nanoparticles among different nanoparticles. Its applications ranged from personal care products, sensors, antibacterial creams, and biomedical applications. The broad range of applications raises concern in regards to their potential toxicity. Therefore, it is required to understand their toxicity mechanism and pattern on various levels. The primary aim of this review is to summarize the cytotoxicity, genotoxicity, neurotoxicity, and developmental toxicity of ZnO nanoparticles in various kinds of cells in vitro and in vivo. Literatures available on ZnO nanoparticles toxicity suggest that dissolution, organism dependent cellular uptake, generation of reactive oxygen species (ROS), and induced inflammatory responses seem to be common factors which govern the toxicity of ZnO nanoparticles.
Keywords: ZnO nanoparticles; cytotoxicity; development toxicity; genotoxicity; neurotoxicity.