To ensure the optimal precipitation percentage, it is important to carefully control these factors during the precipitation process. For example, a higher concentration of titanium sulfate will typically result in a higher precipitation percentage, but may also lead to the formation of impurities. On the other hand, a lower pH of the reaction mixture can promote the precipitation of titanium hydroxide, but may also result in a lower precipitation percentage.

According to the EFSA's Expert Panel on Food Additives and Flavorings 2021 opinion regarding titanium dioxide, it could not rule out a concern for genotoxicity from ingestion of the material based on a perceived gap in data on this risk, which serves as the basis for current ban, said a March report on the decision.

There is some evidence that ingested titanium dioxide does not completely exit the body. A 2015 review of animal studies and a few human studies suggests titanium dioxide can get absorbed into the bloodstream and expose other organs to damage.

TiO₂ NPs appeared to be more toxic to nematode Caenorhabditis elegans than submicron-sized TiO_2.  At a concentration of 1 mg/l, 7 nm particles affected its fertility and survival rate and were more toxic than 20 nm anatase particles. Similarly, Hu et al. showed that rutile particles (10–20 nm), at concentrations above 1 g/kg soil, can be bio-accumulated in earthworms, where they induce oxidative stress, inhibit the activity of cellulase and induce DNA and mitochondrial damage.

5. Is EFSA banning titanium dioxide? 

Neurotoxicity

Titanium dioxide is one of the many oxides formed naturally in our environment. Manufacturers source this mined mineral from rutile, brookite, and anatase. It is then processed and refined to meet stringent safety guidelines based on the end-use for the mineral. 

One of the most widely used food pigments is titanium dioxide, an odorless powder that enhances the white color or opacity of foods and over-the-counter products, including coffee creamers, candies, sunscreen, and toothpaste (1Trusted Source, 2Trusted Source).

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.