Titanium dioxide nanoparticles (TiO₂-NPs) have been widely used in many fields because of their excellent optical and electrical properties. Such widespread use increases their contact with people. However, for safe use, the effects of long-term exposure pathways in vivo should be investigated in detail, but so far, little is known. In our study, we evaluated the effects of different exposure pathways (single vein, intrastomal , and abdominal) on the biological distribution and toxicity of different size TiO₂-NPs in mice. Our results confirm that the biological distribution of TiO₂-NPs depends on the route, time and size of exposure. In the TiO₂-NPs treatment group with size of 25 nm and 50 nm, the particle accumulation in spleen, liver and lung was the highest. Among the three exposure pathways, the biological distribution of TiO₂-NPs in different tissues was also significantly different. The content of titanium in main tissues changed obviously with time, but the rate of change was different. There were also significant differences in organ coefficients between different exposure routes.

https://chinesesites.library.ingentaconnect.com/content/asp/jnn/2016/00000016/00000007/art00070