How does Mira assess titanium dioxide?

Titanium dioxide is a mineral made of titanium and oxygen. It's widely used in cosmetics, food and medicines.

What it does in cosmetics

In cosmetics it plays two main roles:

• White pigment — in toothpastes, lipsticks and lip balms, creams, powders and hair sprays.

• UV filter — in many sunscreens.

Why the rating depends on the form

What matters most for the rating is the form the ingredient takes: nano or non-nano. That determines how easily the particles can get into the body, which is why Mira treats the same substance differently depending on the product.

Nano form (labelled [nano] in the ingredient list)

Nano particles are extremely small and can cross the body's protective barriers. Because of the inhalation risk, regulators restrict them in aerosol sunscreen sprays, and this kind of cosmetic shouldn't be applied to broken skin. Their long-term effects are still being studied. Given these concerns, Mira treats titanium dioxide in nano form as a risky ingredient, pushing the product into the lower bands ("Poor").

Non-nano form

Here the rating depends on whether the substance can get inside the body.

• When there's a risk of swallowing or inhaling it — for example toothpastes, lip products, and sprays (sunscreen or hair). Studies point to possible risks, including genotoxicity, and experts can't yet fully rule them out. For these products Mira treats the ingredient as risky, so the rating drops into the lower bands ("Poor").

• When getting inside the body is unlikely — that is, the product is simply applied to the skin. The particles are too large to pass through the skin, so the risk is lower and this ingredient shouldn't pull the rating down sharply here.

In short

Titanium dioxide is still debated by scientists, especially in its nano form. Mira treats it as risky where it can enter the body (mouth, lungs) and as less of a concern when it's simply applied to the skin. The assessment draws on current findings from authoritative scientific bodies and independent research, and is updated as new evidence appears.

The rating is Mira's opinion. The words "Excellent", "Good", "Poor" and "Bad" refer to the rating, not to the product itself.