Lithopone is an inorganic white pigment, obtained from co-precipitation of Zinc sulfide (ZnS) and Barium sulfate (BaSO4). Titanium Dioxide (TiO2) has replaced Lithopone as a white pigment in majority applications as TiO2 is more durable. However, it is much cheaper than TiO2 and has advantages such as low binder requirement and good dispensability. As a white pigment, it can improve the substrate's weather resistance, and improve the fungicidal properties of paint formulations. Some of the major applications of Lithopone include manufacturing of paint pigments, plastic & rubber products, paper, printing inks, cosmetics, and leather & linoleum products. It is commercially available under names such as pigment white 5, Barium zinc sulfate sulfide, Becton White, C.I. 77115, Charlton White, Enamel White, and Zincolith. On the basis of content of ZnS, Lithopone is available at 28%-30% Lithopone and 60% Lithopone.
How Is Titanium Dioxide Made?
Lithopone is a white pigment (PW5) co-precipitated from solutions of zinc and barium salts according to the following reaction:
Conclusion
The most significant uncertainty identified by the EU experts was the concern that TiO2 particles may have genotoxic effects. Genotoxicity refers to the ability of a chemical to directly damage genetic material within a cell (DNA), which may lead to cancer in certain situations. Although the experts did not conclude that TiO2 particles in E171 are genotoxic, they could not rule out the concern that they might be.
The Sydney Morning Herald reported on the finding of nano particles in our food supply here in Australia, despite no testing every carried out on the safety of these products by our food safety body.
The assessment was conducted following a rigorous methodology and taking into consideration many thousands of studies that have become available since EFSA’s previous assessment in 2016, including new scientific evidence and data on nanoparticles.