lithopone for paints

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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Overall, titanium dioxide plays a vital role in both industrial applications and environmental protection. With China leading the way in the production of high-purity titanium dioxide, the country is well-positioned to meet the growing demand for this essential mineral. By continuing to invest in research and development, China can further enhance its capabilities in titanium dioxide production and contribute to the advancement of global technological innovation.

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Additionally, the committee noted that the available data did not provide convincing evidence of genotoxicity for titanium dioxide as a food additive, but recognized the limitations in current methodologies with respect to the testing of poorly soluble particulate materials. Although there were uncertainties in the genotoxicity data, the experts took into account the fact that the additive was not carcinogenic in adequately conducted two-year studies in mice and rats at doses of up to 7,500 mg/kg BW per day for mice, and 2,500 mg/kg BW per day for rats, the highest doses tested. There was also no evidence of reproductive or developmental toxicity in studies in rats at doses up to 1,000 mg/kg BW per day, the highest doses tested.  

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