ZnO Nanoparticles Impact on Organ Systems in Rats: A Comprehensive Exploration of Diverse Exposure Pathways

Abstract

The synthesis and utilization of nanomaterials with precise spatial dimensions on the nanoscale are pivotal in the field of nanotechnology. In recent years, metal oxide nanoparticles have become increasingly common, raising concerns in the scientific community and the general public about their potential harm to the environment and living organisms. Despite this, there are still significant debates and misconceptions regarding the adverse effects and mechanisms of these nanoparticles. To facilitate their safe and responsible use, it is imperative to gain a comprehensive understanding of their adverse effects. This review aims to provide an overview of the biological fate of zinc oxide (ZnO) nanoparticles in rats through various exposure routes, shedding light on their toxicological consequences and the underlying mechanisms of toxicity. Despite the fact that ZnO nanoparticles have a propensity to target organs such as the liver, kidneys, and lungs, it is noteworthy that higher concentrations of zinc are detected in these tissues following exposure via various routes. The liver plays a central role in the metabolism of ZnO nanoparticles. Multiple exposure routes, including oral, intraperitoneal, intravenous, and intratracheal routes, have been shown to induce liver damage, along with adverse effects on the kidneys and lungs, when exposure occurs via airways. A significant toxicological mechanism associated with ZnO nanoparticles involves the generation of reactive oxygen species (ROS) and the subsequent initiation of oxidative stress. ROS production can result from both the excessive release of Zn⁺² ions and the particulate effect stemming from the semiconductor or electronic properties of ZnO nanoparticles. The potential for surface coatings and modifications holds the promise of further expanding the range of biomedical applications for ZnO nanoparticles, opening up exciting possibilities for futuristic medical treatments, including targeted drug delivery, advanced imaging techniques, and diagnostics.