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.  

Characterization of vitamins@P25TiO₂NPs

What is the FDA limit for titanium dioxide?

Lithopone is an inorganic white pigment, obtained from co-precipitation of Zinc sulfide (ZnS) and Barium sulfate (BaSO4). As a white pigment, it acts as a cost-effective alternative for TiO2. Some of the properties of Lithopone include high brightness and performance under UV exposure. Lithopone requires less wetting agent to achieve optimum wetting of its surface. It is commercially graded on the basis of amount of ZnS. Its grades include 28%, 30%, and 60% ZnS. As a comparatively inexpensive white pigment, Lithopone is presently used in various paint formulations, road marking paints, jointing compounds, and putties.

However, the run rates improved after the Chinese government's consistent efforts to reduce electricity rationing in China. The demand forecast remained positive during the quarter, with inquiries coming in from both the local and international markets. As a result of the supply-demand mismatch, the FOB Wuhu debate for TiO2 rutile grade was decided at 3097 USD/MT at the end of the quarter.

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