Lithopone is rather nontoxic, due to the insolubility of its components. It has been used in medicine as a radiocontrast agent. Lithopone is allowed to be in contact with foodstuffs in the US and Europe.

For research published in 2022 study in the journal Food and Chemical Toxicology, scientists examined “the genotoxicity and the intracellular reactive oxygen species induction by physiologically relevant concentrations of three different TiO2 nanomaterials in Caco-2 and HT29-MTX-E12 intestinal cells, while considering the potential influence of the digestion process in the NMs’ physiochemical characteristics.” They found a “DNA-damaging effect dependent on the nanomaterial,” along with the micronucleus assay suggesting “effects on chromosomal integrity, an indicator of cancer risk, in the HT29-MTX-E12 cells, for all the tested TiO2 nanomaterials.” Researchers concluded that the results showcase “evidence of concern” regarding titanium dioxide used as a food additive.

Variations of titanium dioxide are added to enhance the whiteness of paint, plastics, and paper products, though these variations differ from the food-grade ones for things we eat (1Trusted Source, 2Trusted Source).

The reaction liquid is filtered through plate and frame pressure to obtain lithopone in the form of a filter cake with a moisture content of no more than 45%. It is then roasted in a drying furnace to change the crystal form of lithopone, and is then pickled with sulfuric acid at a temperature of 80°C. Finally, it is washed with water, reinforced with colorants, filtered, dried and ground into powder.

Lithopone