ponceau 4r and titanium dioxide factories

Over the last several years, nanoparticles have come under scrutiny for adverse health effects. Nanoparticles are ultrafine particles between 1 to 100 nanometers in diameter. (To put this in perspective, the average human hair is around 80,000 nanometers thick.) Because of their size, which can be engineered and manipulated at the atomic or molecular level, nanoparticles exhibit unique physical, chemical, and biological properties. Titanium dioxide is one of the most commonly produced nanoparticles in the world.

...

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].

...