Titanium dioxide is authorized for use as a food additive in the European Union. It is used as a white pigment, e.g., in frostings, soups, and sauces. The European Food Safety Authority (EFSA) Panel on Food Additives and Flavourings has published an updated safety assessment of this additive, which had previously been evaluated in 2016. The panel took into account new scientific data gathered and published since. In particular, they considered the effects of TiO₂ nanoparticles present in the food additive.

The panel found that gastrointestinal absorption of TiO₂ particles is low, however, they may accumulate in the body. Studies on general and organ toxicity, as well as reproductive and developmental toxicity, did not indicate adverse effects up to a dose of 1,000 mg/kg bodyweight per day. However, some findings indicate potential immunotoxicity and inflammatory effects for TiO₂, as well as neurotoxicity for TiO₂ nanoparticles. With respect to genotoxicity, the panel concluded that TiO₂ particles have the potential to induce DNA strand breaks and chromosomal damage, but not gene mutations.

The panel concluded that a concern for genotoxicity of TiO₂ particles in food could not be ruled out. Thus, titanium dioxide can no longer be considered safe when used as a food additive according to EFSA’s Panel on Food Additives and Flavourings and no acceptable daily intake can be established. This conclusion does not extend to other uses of TiO₂. Possible regulatory consequences are not up to EFSA, but to the European Commission and the EU member states.

• Safety assessment of titanium dioxide (E171) as a food additive,
  Maged Younes, Gabriele Aquilina, Laurence Castle, Karl‐Heinz Engel, Paul Fowler, Maria Jose Frutos Fernandez, Peter Fürst, Ursula Gundert‐Remy, Rainer Gürtler, Trine Husøy, Melania Manco, Wim Mennes, Peter Moldeus, Sabina Passamonti, Romina Shah, Ine Waalkens‐Berendsen, Detlef Wölfle, Emanuela Corsini, Francesco Cubadda, Didima De Groot, Rex FitzGerald, Sara Gunnare, Arno Christian Gutleb, Jan Mast, Alicja Mortensen, Agnes Oomen, Aldert Piersma, Veronika Plichta, Beate Ulbrich, Henk Van Loveren, Diane Benford, Margherita Bignami, Claudia Bolognesi, Riccardo Crebelli, Maria Dusinska, Francesca Marcon, Elsa Nielsen, Josef Schlatter, Christiane Vleminckx, Stefania Barmaz, Maria Carfí, Consuelo Civitella, Alessandra Giarola, Ana Maria Rincon, Rositsa Serafimova, Camilla Smeraldi, Jose Tarazona, Alexandra Tard, Matthew Wright,
  EFSA J. 2021.
  https://doi.org/10.2903/j.efsa.2021.6585