Because of its unique properties, titanium dioxide is widely used and is well known in nanoscience and nanotechnology. Titanium dioxide was one of the first materials to be used in nanotechnology products. However, the potential toxicity of titanium dioxide nanoparticles is a controversial subject. Many cosmetic companies use titanium dioxide nanoparticles. Because of its bright whiteness, it is used in products such as paints, coatings, papers, inks, toothpaste, face powder, and food colouring.