Titanium dioxide (TiO2) is a multifunctional semiconductor that exists in three crystalline forms: anatase, rutile, and brookite. Owing to an appropriate combination of physical and chemical properties, environmental compatibility, and low production cost, polycrystalline TiO2 has found a large variety of applications and is considered to be a promising material for future technologies. One of the most distinctive physical properties of this material is its high photocatalytic activity (Nam et al., 2019); however, more recently it has attracted growing interest because of its resistive switching abilities (Yang et al., 2008).
Wegman’s puts titanium dioxide in its Original Macaroni and Cheese. Campbell’s Healthy Request Chunky Chicken Corn Chowder has it, as does Food Club’s Chunky New England Clam Chowder. Marzetti uses the color agent to brighten its Cream Cheese Fruit Dip. Dairy products usually don’t need titanium dioxide to look white, but Kroger has decided to add titanium dioxide to its Fat Free Half-and-Half. And titanium dioxide isn’t only in especially white or brightly colored foods: Little Debbie adds it to Fudge Rounds and many other products. According to the Food Scores database maintained by Environmental Working Group, more than 1,800 brand-name food products have titanium dioxide on their ingredients list. That said, it can still lurk as an unspecified “artificial color,” or labels might simply say “color added.”
Different dermal cell types have been reported to differ in their sensitivity to nano-sized TiO2 . Kiss et al. exposed human keratinocytes (HaCaT), human dermal fibroblast cells, sebaceous gland cells (SZ95) and primary human melanocytes to 9 nm-sized TiO2 particles at concentrations from 0.15 to 15 μg/cm2 for up to 4 days. The particles were detected in the cytoplasm and perinuclear region in fibroblasts and melanocytes, but not in kerati-nocytes or sebaceous cells. The uptake was associated with an increase in the intracellular Ca2+ concentration. A dose- and time-dependent decrease in cell proliferation was evident in all cell types, whereas in fibroblasts an increase in cell death via apoptosis has also been observed. Anatase TiO2 in 20–100 nm-sized form has been shown to be cytotoxic in mouse L929 fibroblasts. The decrease in cell viability was associated with an increase in the production of ROS and the depletion of glutathione. The particles were internalized and detected within lysosomes. In human keratinocytes exposed for 24 h to non-illuminated, 7 nm-sized anatase TiO2, a cluster analysis of the gene expression revealed that genes involved in the “inflammatory response” and “cell adhesion”, but not those involved in “oxidative stress” and “apoptosis”, were up-regulated. The results suggest that non-illuminated TiO2 particles have no significant impact on ROS-associated oxidative damage, but affect the cell-matrix adhesion in keratinocytes in extracellular matrix remodelling. In human keratinocytes, Kocbek et al. investigated the adverse effects of 25 nm-sized anatase TiO2 (5 and 10 μg/ml) after 3 months of exposure and found no changes in the cell growth and morphology, mitochondrial function and cell cycle distribution. The only change was a larger number of nanotubular intracellular connections in TiO2-exposed cells compared to non-exposed cells. Although the authors proposed that this change may indicate a cellular transformation, the significance of this finding is not clear. On the other hand, Dunford et al. studied the genotoxicity of UV-irradiated TiO2 extracted from sunscreen lotions, and reported severe damage to plasmid and nuclear DNA in human fibroblasts. Manitol (antioxidant) prevented DNA damage, implying that the genotoxicity was mediated by ROS.
Advanced filtration systems remove any residual impurities post-production Advanced filtration systems remove any residual impurities post-production
china titanium dioxide used in medicine. It can neutralize harmful free radicals in the body, which are known to contribute to the development of various diseases such as cancer and Alzheimer's disease. By incorporating titanium dioxide into dietary supplements or medicinal formulations, researchers believe that it could help protect against these diseases.