TiO2 is also used in oral pharmaceutical formulations, and the Pharmaceutical Excipients handbook considers nano-sized TiO2 a non-irritant and non-toxic excipient. Despite the fact that TiO2 submicron- and nano-sized particles are widely used as food and pharmaceutical additives, information on their toxicity and distribution upon oral exposure is very limited.
In a review published in 2022 in the journal Archives of Toxicology, researchers found that the ingestion of E171 is a “a definite health risk for consumers and their progeny.” After reviewing dozens of in vivo, ex vivo and in vitro studies on the toxicity of E171, the researchers wrote that two facts must be noted: “First, reprotoxicity studies show that animals of both sexes are impacted by the toxicity of these nanoparticles, underlining the importance of conducting in vivo studies using both male and female animals. Second, human exposure begins in utero via maternal-fetal transfer and continues after birth by breastfeeding. Children are then chronically re-exposed due to their food preferences. To be relevant to the human in vivo situation, experimental studies should therefore consider nanoparticle exposure with respect to the age or life period of the studied population.”
Titanium dioxide is used in an enormous range of food products, which can feel jarring when looking at some of its other uses.
When examining a lithopone pigment pricelist, one might notice that prices can vary significantly between different grades of lithopone. Generally, there are two main types Lithopone 28 and Lithopone 60, with the numbers denoting the percentage of zinc sulfide content. Lithopone 28, with a lower zinc sulfide content, is often more affordable compared to Lithopone 60, which offers superior whiteness and opacity. The choice between these grades depends largely on the specific requirements of the end application.