Titanium dioxide

Titanium dioxide (E171) is an inorganic white pigment used in food manufacturing to provide whiteness and opacity to products including chewing gum, confectionery, certain sauces, and powdered foods. Chemically it is dioxotitanium (TiO2, CAS 13463-67-7), one of the most chemically stable inorganic compounds known. Its high refractive index makes it exceptionally effective as a whitener at very low concentrations. In food, it is present as ultrafine particles, and the proportion of particles in the nanometre size range has been a central regulatory concern.

JECFA evaluated titanium dioxide in 2021 and assigned an ADI classification of "not allocated" — meaning available data were insufficient to establish a safe intake level. This designation signals that a numerical limit could not be established due to data gaps rather than demonstrated safety. EFSA reached a similar conclusion in 2021, stating it could "no longer consider titanium dioxide as safe when used as a food additive," primarily due to genotoxicity concerns that could not be excluded.

The European Union banned titanium dioxide as a food additive in August 2022 (EU Regulation 2022/63), following the 2021 EFSA scientific opinion. The ban affects all food categories in EU member states. The additive remains permitted in the United States, Japan, South Korea, and many other markets where regulatory bodies have not taken equivalent action. The EU ban represents one of the most significant food additive reversals in recent regulatory history and reflects application of the precautionary principle in response to persistent uncertainty about nanoparticle genotoxicity. Manufacturers exporting to EU markets must reformulate products containing E171.