It is recommended to store Titanium Dioxide in a well-maintained and dry environment, safeguarding it from exposure to elevated temperatures, open flames, or aromatic chemicals. When transporting Titanium Dioxide pigments, they are commonly packaged in paper bags weighing 25 kg (50 lb) or in large bags constructed from woven polypropylene materials.

≤0.4

Pigment White 5; CI 77115; Deckweiss (Deut.); Lithopone (Deut.); litopón (Esp.); lithopone (Fr.); lithoponio (Gr.); litopone (It.); lithopoon (Ned.); litopone (Port.); Orr's white; oleum white; Griffiths zinc white; Sterling white; Albalith; Charlton white; Ponolith; Jersey Lily white; Sunotlith; Beckton white; Zincolith

In order to contribute with experimental evidence that could help to achieve a better understanding of the field for future regulation, in the present work, the biocompatibility of commercial P25TiO₂NPs (one type of TiO₂NPs used in sunscreen formulations) and two novel functionalized P25TiO₂NPs were evaluated under solar simulated irradiation. White light, generated by red, blue, and yellow LEDs, together with UV ones, was chosen to simulate the solar spectra. Functionalization of TiO₂NPs was made with antioxidant vitamins in order to prevent the expected photo-initiated ROS production when nanoparticles are exposed to the simulated solar spectra. Vitamin B2 (riboflavin) and vitamin C were chosen to carry out the functionalization because they are water-soluble, low-cost, and are a constitutive part of biological processes. In addition, it is known that both have the potential to prevent macromolecular oxidation by ROS [23], [24], [25], [26].

The vitaminC@P25TiO₂NPs, on the other side, did not have any effect on cell protection against ROS. This might be due to the fact that vitamin C, a well-known scavenger of ROS, could behave as prooxidant and even promote ROS and lipid peroxidation [39]. It was recently described that at small concentrations of vitamin C, the prooxidant effects dominate; while in large concentrations the antioxidant ones predominate [40]. The effect also depends on the cell state and the interaction of vitamin C with light. In this case, ascorbic acid may act as an antenna to harvest visible light when conjugated to P25TiO₂NPs. Indeed, it was previously found that this combination (in some ratios) could have an improved photocatalytic activity, possibly due to a red shift in its light absorbance [41]. Further studies on vitaminC@P25TiO₂NPs were not conducted, because of the poor antioxidant capacity [42].

Scattering Power of TiO2 and Pigment Volume Concentration