In a study published in the journal Toxicology, researchers examined the effects of exposing human colon cancer cell line (HTC116) titanium dioxide food additives in vitro. “In the absence of cytotoxicity, E171 was accumulated in the cells after 24 hours of exposure, increasing granularity and reactive oxygen species, inducing alterations in the molecular pattern of nucleic acids and lipids, and causing nuclei enlargement, DNA damage and tubulin depolymerization,” the scientists wrote. Researchers removed the additive from the culture, then examined the results 48 hours later. They found, “The removal of E171 was unable to revert the alterations found after 24 h of exposure in colon cells. In conclusion, exposure to E171 causes alterations that cannot be reverted after 48 h if E171 is removed from colon cells.”

The main concern with nanoparticles is that they are so tiny that they are absorbed into the skin more than we want them (ideally sunscreen should remain on the surface of the skin). Once absorbed they might form unwanted complexes with proteins and they might promote the formation of evil free radicals. But do not panic, these are concerns under investigation. A 2009 review article about the safety of nanoparticles summarizes this, to date, in-vivo and in-vitro studies have not demonstrated percutaneous penetration of nanosized particles in titanium dioxide and zinc oxide sunscreens. The English translation is, so far it looks like sunscreens with nanoparticles do stay on the surface of the skin where they should be.  

Tinting(contrast to the sample)

Faber argued there hasn't been enough change in these federal regulations in the decades following the FDA's approval of titanium dioxide – especially as others increasingly point to potential health consequences.

Worldwide Lithopone Industry to 2027 - Use of Lithopone in the Paints & Coatings Industry is Driving Growth - ResearchAndMarkets.com

Additionally, market demand plays a significant role in determining lithopone pigment prices. Industries such as construction, automotive, and consumer goods have been experiencing fluctuations in demand, influencing the pricing dynamics. In periods of high demand, prices may increase as suppliers adjust to the market trends. Conversely, during downturns or oversupply situations, prices may decrease, providing opportunities for buyers to purchase at more favorable rates.