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.
Founded in 1902 by Henrick J. Krebs, Krebs Pigments and Chemical Company produced lithopone, a widely used white paint pigment also manufactured by DuPont. But Krebs' company had another asset of special interest to DuPont. ...
inner wall coating factories. Many factories are now producing coatings that are low in volatile organic compounds (VOCs) and free from harmful chemicals. These environmentally friendly coatings not only benefit the health of occupants but also contribute to a more sustainable future.The risks associated with titanium dioxide exposure depend on a variety of factors, including the form of the mineral, the route of exposure (such as being inhaled or consumed), and the duration and intensity of exposure.
It adds a bright white color to coffee creamers, baked goods, chewing gums, hard-shell candies, puddings, frostings, dressings, and sauces. But the nanoparticles found in “food-grade” titanium dioxide may accumulate in the body and cause DNA damage—which is one way chemicals cause cancer and other health problems.
Anyway, it doesn't matter if it reflects or absorbs, Titanium Dioxide is a pretty awesome sunscreen agent for two main reasons: it gives a nice broad spectrum coverage and it's highly stable. Its protection is very good between 290 - 350 nm (UVB and UVA II range), and less good at 350-400 nm (UVA I) range. Regular sized Titanium Dioxide also has a great safety profile, it's non-irritating and is pretty much free from any health concerns (like estrogenic effect worries with some chemical filters).
It adds a bright white color to coffee creamers, baked goods, chewing gums, hard-shell candies, puddings, frostings, dressings, and sauces. But the nanoparticles found in “food-grade” titanium dioxide may accumulate in the body and cause DNA damage—which is one way chemicals cause cancer and other health problems.
As early as sixty years ago, zinc sulphide was first thought of as a pigment for coloring India rubber and a patent for the process of its manufacture was issued in England. But it was not until twenty years later that zinc sulphide and its manufacture was seriously considered as a pigment for paint, and in 1874 a patent was issued for a process of manufacturing a white pigment, composed of zinc sulphide and barium sulphate, known as Charlton white, also as Orr's white enamel. This was followed in 1876 by a patent issued to a manufacturer named Griffith and the product, which was similar in character to Charlton white, was known as Griffith's patent zinc white. In 1879 another patent for a more novel process was obtained by Griffith & Cawley, the product made under this process proving the best of the series placed upon the market up to that date. After that time many new processes were patented, all, however, tending to the same object, that of producing a white pigment, composed of zinc sulphide and barium carbonate, the results, however, in many cases ending with failure.
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The composition of lithopone underscores its superiority in specific applications. Ideally, prepared lithopone consists of 30 to 32 percent sulfide of zinc, and a negligible percentage of zinc oxide (1.5%), with the remaining majority being barium sulfate. These attributes render lithopone nearly comparable to the best grades of French process zinc oxide in terms of whiteness. Furthermore, its oil absorption, which sits between lead carbonate and zinc oxide, solidifies its position as a functional and efficient white pigment.
Public health groups urge FDA to cancel titanium dioxide in food, by Center for Science in the Public Interest, May 30, 2023
Titanium dioxide has similar uses in non-food products. It is used in sunscreen as effective protection against UVA/UVB rays from the sun, which creates a physical barrier between the sun’s rays and the skin. It’s also used to whiten paint, paper, plastic, ink, rubber, and cosmetics.
Key benefits for stakeholders
Demand in the European region has been significantly boosted by higher offtakes in the furniture, building, and industrial sectors compared to Q2, after a boost in containment measures. DIY activities increased significantly as people engaged in more home renovation and building tasks during the extended period of lockdown. With the restart of Chinese shipments in the latter half of Q2 2020, supply has also remained plentiful.
Specification
In a 2016 study published in Scientifica (Cairo), Egyptian researchers examined the effects of titanium dioxide nanoparticles on the organs of mice by orally administering the food additive daily, for five days. The results showed that the exposure produced “mild to moderate changes in the cytoarchitecture of brain tissue in a time dependent manner.” Furthermore, “Comet assay revealed the apoptotic DNA fragmentation, while PCR-SSCP pattern and direct sequencing showed point mutation of Presenilin 1 gene at exon 5, gene linked to inherited forms of Alzheimer’s disease.” The researchers wrote: “From these findings, “the present study concluded that TiO2NPs is genotoxic and mutagenic to brain tissue which in turn might lead to Alzheimer’s disease incidence.”