The widespread application of zinc oxide nanoparticles (nano-ZnO) has received increasing attention because of their potential risks to human health and the environment. This review summarizes the relationship between the toxic effects and physicochemical properties of nano-ZnO and the underlying toxicity mechanisms of nano-ZnO. This study presents the possible human health hazards posed by nano-ZnO exposure and the biotoxicity to bacteria, algae, higher plants, aquatic animals, terrestrial invertebrates and vertebrates in vitro and in vivo. The advances in research on the ecotoxicity of nano-ZnO and the potential risks to human health are discussed. Finally, the current research deficiencies in this area are identified, and recommendations for future research are proposed.
Keywords: Zinc oxide nanoparticles; mechanism; physicochemical properties; risk assessment; toxicity.