what is lithopone

Another critical advantage of using TiO2 in pigments is its non-toxic nature. Unlike some traditional pigments that may contain heavy metals or other harmful substances, TiO2 is recognized as safe by regulatory bodies around the world. This attribute allows manufacturers to develop products that are not only visually appealing but also meet stringent health and safety requirements. As consumer awareness about health issues increases, the demand for non-toxic pigments continues to rise, further solidifying TiO2's position in the market.

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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.  

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