Titanium dioxide is used a food colour (E171) and, as with all food colours, its technological function is to make food more visually appealing, to give colour to food that would otherwise be colourless, or to restore the original appearance of food. Titanium dioxide is also present in cosmetics, paints, and medicines.

In a 2019 study published in the journal Nanotoxicology, researchers recreated the first phase of digestion in mice and fed them titanium dioxide, then examined whether accumulation occurred in the organs. Researchers wrote: “Significant accumulation of titanium was observed in the liver and intestine of E171-fed mice; in the latter a threefold increase in the number of TiO2 particles was also measured. Titanium accumulation in the liver was associated with necroinflammatory foci containing tissue monocytes/macrophages. Three days after the last dose, increased superoxide production and inflammation were observed in the stomach and intestine. Overall, [this] indicates that the risk for human health associated with dietary exposure to E171 needs to be carefully considered.”

FAQ – EFSA 2021 safety assessment of titanium dioxide (E171)

Titanium dioxide has been used as a bleaching and opacifying agent in porcelain enamels, giving them brightness, hardness, and acid resistance. In modern times it is used in cosmetics, such as in skin care products and sunscreen lotions, with claims that titanium dioxide protects the skin from ultraviolet radiation because of its property to absorb ultraviolet light.

Lithopone B301, Lithopone B311 Powder

Here it has been shown that functionalization of P25TiO2NPs with vitamin B2 was able to significantly decrease the oxidative stress produced when they are exposed to sunlight. This finding is of main importance to prevent skin damage and toxicity of sunscreens containing this form of untreated titanium dioxide and should be taken into consideration when updating the regulations mentioned above .

According to the American Chemistry Council, titanium dioxide (TiO2) is an inorganic substance that's used as a white powder in a variety of industrial and consumer goods, including in sunscreen, cosmetics, toothpaste, paint, plastics, food and more.

The precipitation of titanium dioxide involves the reaction of titanium sulfate with an alkaline solution to form titanium hydroxide, which is then calcined to produce titanium dioxide. The precipitation process is crucial for achieving the desired particle size distribution, crystallinity, and purity of the final product.

Animal studies have shown that, when consumed as a food additive, titanium dioxide can induce intestinal inflammation.