UV filter ingredient
Terephthalylidene Dicamphor Sulfonic Acid
A water-soluble, photostable organic UVA filter (Ecamsule/Mexoryl SX) approved in the EU at up to 10% that absorbs UV radiation predominantly in the UVA range.
Also known as: ecamsule, mexoryl sx, tdsa
uva-filterphotostabilizer
Benefits
- ✓Provides broad UVA protection (290–400 nm, peak at 345 nm)
- ✓Highly photostable; does not degrade on sunlight exposure
- ✓Water-soluble, suitable for lightweight fluid sunscreen formulations
Watch for
- ⚠Approved up to 10% in the EU; not FDA-approved for OTC sunscreens in the US as a standalone filter
- ⚠Very low systemic absorption; minimal safety concerns reported in studies
- ⚠Ethanolamines used as neutralizers in commercial versions may rarely cause contact dermatitis
