After conducting a review of all the relevant available scientific evidence, EFSA concluded that a concern for genotoxicity of TiO2 particles cannot be ruled out. Based on this concern, EFSA’s experts no longer consider titanium dioxide safe when used as a food additive. This means that an Acceptable Daily Intake (ADI ) cannot be established for E171.
Some small test-tube research has shown that these nanoparticles are absorbed by intestinal cells and may lead to oxidative stress and cancer growth. However, other research has found limited to no effects (13Trusted Source, 14Trusted Source, 15Trusted Source).