Relationship between the Physical Properties and Mechanisms of Toxic Action for Nanopowders and Micropowders of Titanium Dioxide in the Form of Anatase

Autor: Ryabtseva, M. S., Krivobok, V. S., Kolobov, A. V., Dimitrieva, S. E., Shevchenko, M. A., Chentsov, S. I., Nikolaeva, I. Yu., Tarnopolskaya, M. E.
Zdroj: Nanobiotechnology Reports; December 2022, Vol. 17 Issue: 6 p846-856, 11p
Abstrakt: Abstract: For titanium-dioxide powders in the form of anatase with an average particle size of ~10 μm and ~10 nm, comprehensive studies are carried out demonstrating the relationship between the physical properties of particles and their biological effect on living organisms. Data from a 28-day oral toxicity study in rats show that regardless of the TiO2-particle size in the form of anatase, it has a mild toxic effect, mainly associated with violations in the nitrogen metabolism and the body’s hydration system. The systemic bioavailability of TiO2is confirmed from the gastrointestinal tract with a pronounced tropism for liver tissues. Signs of a dependence on the particle size are not recorded. For 5% of animals, a significant interrelated increase in the concentration of titanium in the blood and in the brain is found, indicating the presence of an internal factor affecting the bioavailability of TiO2. The obtained experimental data indicate that, upon the alimentary intake of nanoparticles of the anatase phase of TiO2, the implementation of toxic effects associated with the chemical and catalytic activity of the surface of nanostructures is difficult. Model experiments have shown that a similar toxicological effect of nanofractions and microfractions is caused by colloidal instability and a tendency to the agglomeration of TiO2nanoparticles in aqueous solutions with a pH of ~3–7. The ability of the studied particles to agglomerate also makes it theoretically possible to exclude the paracellular transfer of TiO2from the gastrointestinal tract to the internal environment of the body. However, the question of the mechanisms of the accumulation of titanium dioxide in the body and its toxicity with longer exposure remains open.
Databáze: Supplemental Index
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