Menthyl Anthranilate

Menthyl Anthranilate is an organic UV filter used to soak up rays in the near UVA-range. It's an ester made from anthranilic acid and menthol.

The catch with this ingredient is that it's pretty weak and narrow at what it does; its protective coverage peaks at ~340 nm so it misses a big chunk of the long-wave UVA that contributes to photoaging.

Laboratory work has also shown that it isn't very photostable and it loses a good portion of its absorbing power after extended UV exposure.

There's also solid photophysics research showing it's highly fluorescent; when it absorbs UV light, it doesn't release all that energy cleanly as heat. A small amount (~9-12%) gets passed to oxygen, creating reactive molecules called singlet oxygen that can stress skin.

It's a minor effect but also why this ingredient is almost always paired with antioxidants. Think of it as needing good teammates to behave well in a formula and not a safety red flag.

Concentration-wise, it's permitted up to 5% as an OTC sunscreen active but it's usually formulated lower (2-4%). It also is not approved for cosmetic use in the EU.