Tinosorb S (bemotrizinol)
INCI Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine
A broad-spectrum, highly photostable UV filter covering UVB and UVA that also stabilises other filters. Permitted in the EU at up to 10%.
- Typical use range
- Up to 10% (EU Annex VI) per the literature, not our formula
- Also known as
- Tinosorb S, Bemotrizinol, BEMT
Bis-ethylhexyloxyphenol methoxyphenyl triazine, sold as Tinosorb S and known generically as bemotrizinol, is an oil-soluble organic filter that absorbs across both UVB and UVA, with absorption peaks near 310 nm and 343 nm. A single ingredient that covers both bands simplifies a sunscreen and reduces the total load of filters needed.
It is one of the most photostable filters available: it does not degrade meaningfully under sunlight, and it protects less stable filters in the same formula from breaking down. Its large molecule stays on the surface of the skin, which is where a sunscreen should work.
It is approved in the EU at up to 10% (Annex VI) and used across Europe, Australia and much of Asia, including in many of the sunscreens sold in India. It dissolves into the oil phase and blends into light lotions and gels without a white cast, which is why it anchors so many of the sunscreens that stay wearable in humid weather.
Where you will find it.
- Silk Veil SPF 50+ PA++++ Sunscreen Sunscreen In the INCI
Percentages are read from each product's stated active complex. Where none is stated the ingredient appears in the full INCI only.
Is Tinosorb S the same as Tinosorb M?
No. Both are broad-spectrum filters, but Tinosorb S (bemotrizinol) is oil-soluble and works by absorption, while Tinosorb M (bisoctrizole) is a water-dispersed particle that absorbs and scatters. Many sunscreens use both.
Why do I rarely see this filter in American sunscreens?
Sunscreen filters are regulated as drugs in the US, where the approved list has changed little since the 1990s. Bemotrizinol is approved in the EU, Australia and most of Asia.
- CosIng, Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine (EU cosmetic ingredient database) ec.europa.eu/growth/tools-databases/cosing/
- Regulation (EC) No 1223/2009 on cosmetic products, Annex VI (UV filters allowed in cosmetic products).
- Osterwalder U, Sohn M, Herzog B. Global state of sunscreens. Photodermatol Photoimmunol Photomed. 2014;30(2–3):62–80.