For a mini-review published in the journal Particle and Fibre Technology in 2021, scientists wanted to evaluate whether Ti02 particles contributed to the development and/or exacerbation of irritable bowel disease, and whether they altered the four elements of intestinal barrier function: the intestinal microbiota, the immune system, the mucus layer, and the epithelium. The breakdown of these four elements can contribute to autoimmune, neurological, inflammatory, infectious, and metabolic diseases. Following their review, the researchers concluded: “Data indicate that TiO2 is able to alter the four compartments of IBF and to induce a low-grade intestinal inflammation associated or not with pre-neoplastic lesions.” 

What exactly is titanium dioxide?

Customer sues Mars:Skittles are 'unsafe' for consumers, lawsuit charges, because they contain 'a known toxin' 

For his part, Kaminski argues most of the studies have been in animals, and any effects found were minuscule. He and his team also contested some of the findings in a 2019 study that found no evidence of increased inflammation or changes in the GI tract.

Public health groups urge FDA to cancel titanium dioxide in food, by Center for Science in the Public Interest, May 30, 2023

Titanium dioxide is often listed in the ingredients list on the product label when used in home, beauty and personal care products.

The Colour of Barium Sulphate and Its Suppliers