Titanium dioxide (E 171) is authorised as a food additive in the EU according to Annex II of Regulation (EC) No 1333/2008.  

That came after a 2021 report from an expert panel at the European Food Safety Authority, which reviewed data on titanium dioxide safety. The panel said it couldn’t rule out concerns that the food additive might be able to damage DNA and possibly lead to cancer. They explained that after you eat something that has titanium dioxide in it, your body absorbs low levels of its particles – but the particles can build up as you eat more foods with this additive.