The risks associated with titanium dioxide exposure depend on a variety of factors, including the form of the mineral, the route of exposure (such as being inhaled or consumed), and the duration and intensity of exposure.

We've used titanium dioxide safely for decades. However, recently its safety was called into question. 
 
At CRIS, we've explored the safety of titanium dioxide for nearly half a decade, including conducting double-blind research to test the safety of food-grade titanium dioxide (E171). Our study shows that when exposed to food-grade titanium dioxide in normal conditions, research animals did not experience adverse health outcomes.
 
It's important to emphasize that in a National Institutes of Health study, experimental animals were exposed to titanium dioxide in amounts as high as 5% of their diet for a lifetime and showed no evidence of adverse effects. 
 
A handful of studies greatly influenced the decisions made by the European Food Safety Authority (EFSA). Unfortunately, these studies did not consider that titanium dioxide exposure comes from food, not drinking water. Additionally, CRIS researchers could not reproduce the adverse outcomes identified by the studies through typical food ingestion. Regardless, the EFSA banned E171 as a food ingredient and for use in other capacities in the summer of 2022.
 
In 2022, the United States, United Kingdom, and Canada maintained that the scientific evidence supports that titanium dioxide (E171) is safe for humans to use and consume.

The brands of lithopone of the normal class, that of chemical manufacture, are marketed under such names as Ponolith, Beckton White, Jersey Lily White, Oleum White, Zinc Sulphide White, all of these being of domestic manufacture, and their composition is of the 30 per cent. zinc sulphide type. The German manufacturers and exporters of lithopone make use of fancy names for their brands and here are a few examples of these and the composition of the pigment:-

But in the U.S., titanium dioxide is found all over the grocery shelves. Candy like Skittles, Starbursts, and Jell-O, gum like Trident White peppermint gum and Mentos Freshmint Gum, cake products like Duncan Hines Creamy Vanilla Frosting, and Nabisco Chips Ahoy! cookies are just a few of the myriad food items that contain the additive.

Blanc de Comines, 27 per cent zinc sulphide, 70.5 per cent barium sulphate, 2.5 per cent zinc carbonate.

Overwhelmingly, research that’s relevant to human eating patterns shows us that E171 is safe when ingested normally through foods and drugs (1,2).

Oman Bans Food Products Containing Titanium Dioxide, by Gulf News Report, July 23, 2023