Food preservation and packaging

2C+O2→2CO2

In sunscreen, titanium dioxide is used as a barrier to keep the sun's ultraviolet (UV) rays from damaging your skin. It's processed into much smaller particles than what goes into food, called nanoparticles. In this form, it becomes transparent, and also absorbs UV light so it doesn't reach your skin.

Titanium dioxide is produced in two main forms. The primary form, comprising over 98 percent of total production, is pigment grade titanium dioxide. The pigmentary form makes use of titanium dioxide’s excellent light-scattering properties in applications that require white opacity and brightness. The other form in which titanium dioxide is produced is as an ultrafine (nanomaterial) product. This form is selected when different properties, such as transparency and maximum ultraviolet light absorption, are required, such as in cosmetic sunscreens.

Animal studies have shown that, when consumed as a food additive, titanium dioxide can induce intestinal inflammation.

Titanium dioxide is a naturally-occurring mineral found in the earth’s crust. Because of its white color, opaqueness, and ability to refract light, the ingredient is often used as a pigment, brightener, and opacifier, which is an ingredient that makes a formulation more opaque. Titanium dioxide is also a UV filter and so is an effective active ingredient in sunscreens. It’s often used in cosmetic loose and pressed powders, especially “mineral powder” cosmetics, in addition to other cosmetics, lotions, toothpaste, and soap.

Some dealers quoted prices that were significantly higher than expected, sending the domestic market to an almost three-year high. Meanwhile, a similar scenario was observed in the Indian market, where titanium dioxide prices (rutile grade) for rose by 8% from January to March. The increase was attributed to strong demand from the domestic paints and coatings sector as well as premium cargo from China.

In addition to the toxic effects of TiO₂ NPs, discussed in previous chapters, these NPs have been also shown to promote photosynthesis and nitrogen metabolism, resulting in the enhanced growth of spinach. It increases the absorption of light and accelerates the transfer and transformation of the light energy. It was also found that treatment with nano-sized TiO₂ significantly increased the level of antioxidant enzymes, and decreased the ROS accumulation and malonyldialdehyde content in spinach chloroplasts under visible and UV irradiation. TiO₂ NPs also increased the superoxide dismutase activity of germinating soybean, enhanced its antioxidant ability, and promoted seed germination and seedling growth.