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Be

Bemotrizinol

Bis-Ethylhexyloxyphenol Methoxyphenyl TriazineSPF filter

Modern broad-spectrum chemical UV filter. Highly photostable, low-irritation profile. EU/AU/JP-approved; not yet FDA-approved for the US.

What it does

Bemotrizinol is one of the highest-performing chemical UV filters available — broad-spectrum (UVB + UVA1 + UVA2), photostable on its own, and well-tolerated. It's standard in European, Asian, and Australian sunscreens but not currently FDA-approved in the US (the gap is regulatory, not safety-driven). If you can source non-US sunscreens, bemotrizinol-based formulations are often the best chemical-filter option for sensitive or dark skin tones.

The evidence, graded

emergingAvobenzone is not sufficiently photostable on its own; pairing it with a broadband filter such as bemotrizinol (Tinosorb S) prevents its photodegradation in a concentration-dependent way and preserves SPF and UVA protection through sun exposure.Chatelain 2001 · Photochemistry and photobiology ↗
emergingBemotrizinol (Tinosorb S), a modern broadband UV filter, resists photodegradation and holds its SPF and UVA protection after strong sun exposure, and it can stabilize less-photostable filters co-formulated with it.Chatelain 2001 · Photochemistry and photobiology ↗
emergingIn a photostability comparison of five UV filters, formulations containing bemotrizinol were the most photostable, while the US-approved filters avobenzone and octinoxate were significantly degraded after UV exposure.Freitas 2015 · European journal of pharmaceutical sciences ↗
emergingPhotolabile UV filters such as avobenzone and octinoxate degrade under sunlight but can be stabilized by more photostable filters like bemotrizinol through optical-density and triplet-quenching mechanisms.Herzog 2020 · Photochemical & photobiological sciences ↗

Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.

Also known as

tinosorb s, bis-ethylhexyloxyphenol methoxyphenyl triazine

Pairs worth knowing

Avobenzone · works together ↗Octinoxate · works together ↗

Read more

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