On absorption of UV light, photo-generated titanium dioxide particles create singlet oxygen, superoxide anions (O2-) and hydroxyl radicals (OH-) that are potent free radicals (1,2). Irradiated particles of titanium dioxide can induce oxidative damage to DNA (2) which can lead to the development of mutant cells and skin cancers (3,4,5,6) and lipid peroxidation of essential functions on the cell membrane (7).

We apply titanium dioxide to our skin through sunscreens, makeup, lip balms, nail polish, and other cosmetic products. 

In food, titanium dioxide has a few different uses. Most notably, its food-grade form is used as a colorant to enhance and brighten the color of white foods such as dairy products, candy, frosting, and the powder on donuts. For foods that are sensitive to UV light, titanium dioxide is used for food safety purposes to prevent spoilage and increase the shelf life of food.

2. Cosmetics With its UV-filtering properties, anatase TiO2 is a popular ingredient in sunscreens and cosmetic formulations. Its ability to scatter UV radiation effectively protects the skin from harmful sun exposure, contributing to the increasing popularity of natural and mineral makeup products.

But a chemical’s safety when it’s used externally is not always the same as when it’s ingested. Different uses of the same ingredient may cause very different health outcomes.

In 2023, California and New York proposed banning several food additives that are banned in Europe but legal in the United States. Titanium dioxide was among the five proposed to be banned, but in September, the additive was removed from the list of additives from the California ban list.

If you want to avoid titanium dioxide, Stoiber and Faber urge consumers to try and avoid processed foods as best as you can.

Titanium dioxide particles help light scatter and reflect, Kelly Johnson-Arbor, MD, a medical toxicology physician at the National Capital Poison Center, told Health. Because of that, we often use it as a whitening agent.

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Exposure to titanium dioxide in utero and in breastfeeding children

Manufacturers use titanium dioxide in some packaging to protect food from exposure to sunlight. Lab studies show it may also help stop bacteria from growing, and break down a gas that makes many fruits and vegetables ripen faster. That can keep products fresher and give them a longer shelf life.   

Lithopone powder, chemically known as zinc sulfide/zinc oxide, is a white pigment produced through a precipitation process involving zinc sulfate and barium sulfate. It is characterized by its high refractive index, excellent hiding power, and resistance to UV radiation, making it an ideal choice for various applications.

Titanium Dioxide is one of the two members of the elite sunscreen group called physical sunscreens (or inorganic sunscreens if you’re a science geek and want to be precise).

In a study published in 2022 in the journal Particle and Fibre Technology, researchers examined the impact of maternal exposure to titanium dioxide nanoparticles in newborn offspring mice. They found that “a chronic exposure to TiO2 NPs during pregnancy alters the respiratory activity of offspring, characterized by an abnormally elevated rate of breathing.” Breathing was also shown to be “significantly and abnormally accelerated,” and the ability for neural circuitry to effectively adjust breathing rates was impaired. The researchers concluded: “Our findings thus demonstrate that a maternal exposure to TiO2 NPs during pregnancy affects the normal development and operation of the respiratory centers in progeny.”

Titanium dioxide is used in an enormous range of food products, which can feel jarring when looking at some of its other uses.

Nanotoxicology