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Tropolone

What Tropolone is & what it does

Tropolone is a small aromatic compound built around a seven-membered carbon ring, found naturally in some plants and also made synthetically. In cosmetic formulas it is commonly used as a preservative or stabilizer because it can bind metal ions and help limit microbial growth. Its ability to chelate metals also makes it useful for keeping a product chemically stable over time.

Is Tropolone safe in skincare?

Tropolone is used in cosmetic formulas at low concentrations, typically as a preservative or stabilizer, where it is considered acceptable for that purpose. Like other preservative-type ingredients, it is included in small amounts to help keep a product fresh. If you have sensitive skin, a patch test with the finished product is a sensible precaution.

What does Tropolone do in skincare?

In skincare, Tropolone is commonly used to help preserve and stabilize a formula. It can bind metal ions, which helps slow chemical breakdown, and it has properties that can limit microbial growth. This supports a product's shelf life and consistency rather than providing a direct skin benefit.

Is Tropolone natural or synthetic?

Tropolone occurs naturally in some plants and fungi, but the material used in cosmetics is commonly produced synthetically for purity and consistency. Whether it is labeled natural or synthetic depends on the specific source a manufacturer uses. Chemically it is the same compound regardless of origin.

Sunscreens with Tropolone

We rate 59 sunscreens that contain it, showing the top 10 by overall score:

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