ABSTRACT
Metal oxide nanoparticles (MeO-NPs) are some of the most widely used nanomaterials in the agriculture, consumer product, and energy sectors. Their increased requirements and wide applications can necessarily cause harm to ecosystems and organisms. So, it is vital to understand the main mechanisms of MeO-NPs toxicity before they cause harmful effects on human health. This chapter summarizes the toxic effects of MeO-NPs using freshwater fish as models. Factors discussed in this chapter that can affect the nanotoxicity include particle size and shape, surface chemistry and its modification, chemical composition, solubility, and pH of the system. The mechanisms of MeO-NPs toxicity to aquatic organisms can be defined in three basic prospects: overproduction of reactive oxygen species (ROS); release of metallic ions; and particle cell interaction by electrostatic force that can cause lipid peroxidation, oxidative stress, and damage to cell membranes and DNA. A literature review also quantitatively evaluates the scientific research work on MeO-NPs and fish. We also highlight the knowledge gaps and the need for future research.
