Titanium dioxide is used in paints, plastics, pharmaceuticals, food and cosmetics. Almost anything white is likely to contain titanium dioxide. It is known for its brightness, opacity and ability to block ultraviolet rays. TiO2 has been used as an additive in many products in many industries for so long that it is considered a safe material.

The use of nanoscale titanium dioxide, sometimes called ultrafine-grade titanium dioxide, warrants caution, as there is concern about the effects of inhaling dust during manufacturing and processing. Its small size makes employees at production facilities particularly vulnerable to respirable airborne particles.

Currently, only a small percentage of titanium dioxide manufactured is nanoscale but that proportion is growing. Some advantages over standard TiO2 are increased transparency and lightness. This means that a smaller amount of product containing nano TiO2 is needed, which is a benefit to sunscreen or cosmetic users. Makers of personal care products are naturally increasing their use of nano TiO2, which means there is greater potential exposure to employees in every step of the manufacturing process.

Another common use of nanoscale TiO2 is as a support material for catalyst applications, often in the automotive industry or in power stations.

In February 2020, the European Commission classified inhalable titanium dioxide powder as a category 2 suspected carcinogen. Further research exploring the carcinogenic effects of TiO2 inhalation is ongoing and hotly debated.