Common Name(s): Mexoryl sx,ecamsule,tdsa
CAS Number: 90457-82-2
DESCRIPTION
What It Does: Provides photostable water-phase uva-ii protection — the only water-soluble uva filter enabling aqueous-phase broad-spectrum coverage.
Why It's Used: The only significant water-soluble uva filter — mexoryl sx enables uva protection in aqueous phases where all other uva filters (oil-soluble) cannot be placed, enabling superior broad-spectrum coverage across both phases.
How It Works: Sulfonic acid groups provide high water solubility. absorbs uva-ii (λmax 345nm). photostable via esipt (excited state intramolecular proton transfer) mechanism. water-phase uva coverage complements oil-phase filters.
Typically Found In: Water-based sunscreens,l'oréal la roche-posay products
TECHNICAL DETAILS
Primary Category: Active ingredient – water-soluble uva filter
Secondary Functions: Skin conditioning
Application Areas:
Facial Skincare
Body Care
Hair Care
Beard Care
Color Cosmetics (Makeup)
Dietary/Oral Supplements
Typical Concentration Range: Up to 10% (eu), 3% (us fda)
SOURCING & ETHICS
Vegan Status: Conditional - supplier confirmation required
Halal Status: Unverified - supplier confirmation required
Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier. [audit 2026-07-29 rev2: the record's own source_notes does not assert a non-animal origin, or instructs the reader to verify with the supplier; "yes" asserts knowledge the record does not hold. determination requires shariah-panel sign-off.]
SKIN COMPATIBILITY
Irritancy Rating: 1/5 – very low
Comedogenicity Rating: 0/5 – non-comedogenic
Sensitivity Concerns: Well-tolerated by most skin types.
Safe for Sensitive Skin: Yes
SAFETY & COMPATIBILITY
Safety Profile: Eu max 10%. fda approved at 3% (rare non-us filter fda approval). ewg score: 1.
Works Well With: Standard skincare actives
Avoid Combining With: No known significant incompatibilities
SCIENTIFIC NOTE
Mexoryl sx is one of only two non-us-developed uv filters ever approved by the fda (as of 2025). this fda approval reflects its exceptional safety profile validated through l'oréal's extensive clinical programme and the unique clinical need for a water-soluble uva filter not served by any other approved compound.
Last Verified: 2026-03-12
Primary Sources: Cosing database,fda mexoryl sx approval,l'oréal tdsa research