The integrity of surface skin cells was evaluated with and without solar simulated irradiation. The integrity of the stratum corneum was significantly lower in individuals treated with P25TiO₂NPs under the light in comparison to the ones that received the functionalized nanoparticles. Cell membrane suffering is evident (Fig. 9), and it is in accordance with the ROS levels and macromolecule oxidation found in vitro for the irradiated P25TiO₂NPs. Disruption of the superficial skin layer was observed in all animals treated with no functionalized nanoparticles, under irradiation. This data expands the findings by the group of Professors Fubini and Fenoglio, who showed that P25TiO₂NPs could impact the lipid structure at the top few microns of the stratum corneum [55]. Control skin under irradiation and without any topic formulation did not show changes in cell structure.

For a substance that is relatively unknown to the public, it’s amazing how many everyday products TiO2 can be found in. Because of its many varied properties, our skin, cities, cars, homes, food and environment are made brighter, safer, more resilient and cleaner by TiO2. With a legacy of 100 years of safe commercial use, TiO2 is only going to become more vital as our environment faces greater challenges from a growing population.

In 2022, a year after the EFSA recommended against the use of E171, the Food Standards Australia New Zealand (FSANZ) conducted its own reassessment of titanium dioxide as a food additive. The agency concluded that titanium dioxide was indeed safe to use as a food additive. The United Kingdom and Canada came to similar conclusions.