The toxicological effects of nano titanium dioxide on target organs and mechanisms of toxicity

Nano-titanium dioxide (TiO2NPs) is widely used for its extremely high stability, corrosion resistance, and photocatalytic properties and has penetrated into various fields of production and life. Assessing its toxicity to different organs should be a key part of preclinical toxicity assessment of TiO2NPs, which is relatively incomprehensive yet. Therefore, this review focuses on the toxic effects of TiO2NPs on various organs in mammals and biological mechanisms from different organs. The commonality of toxic effects on various target organs reflected in tissue structure damage and dysfunction, such as liver damage and dysfunction; pulmonary fibrosis; and renal impairment (including hematuria and nephritis); damage of brain tissue and neurons; alteration of intestinal villi; and weight loss. And effects on the reproductive system are affected by different sexes, including ovarian dysfunction, testicular development damage, and sperm viability reduction. We believe that the toxic mechanisms of TiO2NPs in target organs have commonalities, such as oxidative stress, inflammatory responses, and organelle damage. However, different target organ toxicities also have their specificities. TiO2NPs disturb the intestinal flora and cause undesirable changes in feces products. And in spleen are infiltration of neutrophils and lymphadenopathy and eventually immune deficiency. Although the toxic pathways are different, but there may be a close link between the different toxic pathways. In this article, the main manifestations of the toxic effects of titanium dioxide nanoparticles on major mammalian organs are reviewed, in order to provide basic data for their better application from a medical perspective. The potential harm of nano-titanium dioxide on normal cells and organs across multiple bodily systems, and its subsequent impact on human health, were the primary focus of this review. Specifically, the toxic effects of nano-titanium dioxide on various organs and the potential biological mechanisms at different organ levels were discussed. Notably, the brain was found to be particularly susceptible to the oxidative toxic effects of nano-titanium dioxide compared to other bodily systems. Additionally, exposure through the respiratory system was found to elicit more pronounced inflammatory effects compared to alternative exposure routes.

Automated summary

This review focuses on the toxic effects of TiO2NPs on various organs in mammals and the biological mechanisms at different organ levels. The findings suggest that TiO2NPs can cause damage and dysfunction in liver, lung, kidney, brain, intestine, and reproductive system, with common toxic mechanisms including oxidative stress, inflammatory responses, and organelle damage. The review provides basic data on the toxic effects of nano-titanium dioxide on major mammalian organs, aiming to support its better application in medicine and evaluate potential health risks.