Fig. 5. ROS values (Abs of NBT) in samples of MSSA treated with A: 0.2 mg/mL P25TiO2NPs; B: 0.02 mg/mL P25TiO2NPs; C: 0.2 mg/mL VitaminB2@P25TiO2NPs; D: 0.02 mg/mL VitaminB2@P25TiO2NPs after 3 h of irradiation (red) and 6 h (blue). SD < 0.20 and p < 0.05 between C-D and A-B.
Faber argued there hasn't been enough change in these federal regulations in the decades following the FDA's approval of titanium dioxide – especially as others increasingly point to potential health consequences.
Another crucial property of TiO2 is that it can show photocatalytic activity under UV light. This makes it effective for environmental purification, for different kinds of protective coatings, sterilisation and anti-fogging surfaces, and even in cancer therapy.
The most significant uncertainty identified by the EU experts was the concern that TiO2 particles may have genotoxic effects. Genotoxicity refers to the ability of a chemical to directly damage genetic material within a cell (DNA), which may lead to cancer in certain situations. Although the experts did not conclude that TiO2 particles in E171 are genotoxic, they could not rule out the concern that they might be.