Stability and darkening:

Titanium dioxide (E171) is an additive that is used in food as a colour. The function of food colours 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 used to provide whiteness and opacity to foods.

Titanium dioxide is a mineral that’s used as a white coloring in a variety of products, including sunscreens, cosmetics, paints, and plastics. The pigment grade is also known as titanium white, pigment white 6, or CI 77891; it's the whitest and brightest of all known pigments.

The mineral appears to have low skin penetration, but it is a greater concern when inhaled frequently over time.

Titanium dioxide, also called titania, is an odorless white powder and naturally occurring mineral that is widely used as a pigment for its brightness and whitening effects on a variety of materials, such as paint, plastic, paper, cosmetics, sunscreens, toothpastes and foods.

Le Lithopone s'utilise au maximum à 10% du liant employé, sans quoi, il sera nécessaire d'utiliser des fixateurs & adjuvants.

Even though it is one of the most-produced chemicals, the real and potential benefits of titanium dioxide are not without controversies. Dust inhalation may cause breathing problems. Titanium dioxide has been classified by the International Agency for Research on Cancer as an Group 2B carcinogen, a “possible carcinogen to humans,” based on studies of rats that inhaled the substance.

In an early study Jani et al. administred rutile TiO₂ (500 nm) as a 0.1 ml of 2.5 % w/v suspension (12.5 mg/kg BW) to female Sprague Dawley rats, by oral gavage daily for 10 days and detected presence of particles in all the major gut associated lymphoid tissue as well as in distant organs such as the liver, spleen, lung and peritoneal tissue, but not in heart and kidney. The distribution and toxicity of nano- (25 nm, 80 nm) and submicron-sized (155 nm) TiO₂ particles were evaluated in mice administered a large, single, oral dosing (5 g/kg BW) by gavage. In the animals that were sacrificed two weeks later, ICP-MS analysis showed that the particles were retained mainly in liver, spleen, kidney, and lung tissues, indicating that they can be transported to other tissues and organs after uptake by the gastrointestinal tract. Interestingly, although an extremely high dose was administrated, no acute toxicity was observed. In groups exposed to 80 nm and 155 nm particles, histopathological changes were observed in the liver, kidney and in the brain. The biochemical serum parameters also indicated liver, kidney and cardiovascular damage and were higher in mice treated with nano-sized (25 or 80 nm) TiO₂ compared to submicron-sized (155 nm) TiO₂. However, the main weaknesses of this study are the use of extremely high single dose and insufficient characterisation of the particles.

Titanium dioxide is added to some food packaging to preserve the shelf life of a product.

We've measured many different immunological markers, both in the mucosa of the intestine and the lymphoid organs part of the intestine and we didn't see any inflammation there or changes in white blood cell number, Kaminski said. They also looked at the spleen where titanium dioxide was taken up into the bloodstream. You would expect [titanium dioxide] would be filtered out in the spleen and maybe induce inflammation there, but we did not see that, Kaminski added.

Matthew Wright, chair of the authority's working group on titanium dioxide, noted that the evidence for general toxic effects was not conclusive, but that the panel couldn't rule out genotoxicity entirely. There were also some current data limitations and the assessment could not establish a safe level for daily intake of the food additive, he stated.

While IARC listed titanium dioxide as “possibly carcinogenic to humans,” they also add that “there is inadequate evidence in humans for the carcinogenicity of titanium dioxide.” Of the four human studies that they reviewed, only one showed a potential risk for occupational workers inhaling titanium dioxide particles and lung cancer, while the other three showed no risk for cancer at all. And it’s key to note that IARC did not assess the effects of titanium dioxide found in foods.

Apart from the cosmetics industry, the coatings and plastics industry is also expected to contribute significantly to the growth of titanium dioxide in 2023. Coatings made from titanium dioxide offer excellent hiding power, durability and weather resistance, making them ideal for outdoor applications. Demand for high-quality coatings is expected to surge as the construction and automotive industries expand. Titanium dioxide is at the forefront of providing aesthetic and protective coatings, making it an indispensable ingredient in the industry.