active
Avobenzone
The only globally available synthetic UV filter with coverage across the full UVA spectrum (310–400 nm). Reformulation pressure continues as FDA GRASE non-determination drives US clean brands toward mineral SPF.
Benefits
- Full UVA I + UVA II coverage (310–400 nm)
- High molar absorption coefficient
- Oil-soluble — compatible with aesthetic sunscreen vehicles
- FDA-approved (up to 3% US; 5% EU)
- Critical for broad-spectrum claims in US formulations
Example uses
- Broad-spectrum chemical sunscreens
- SPF sun serums
- Daily SPF moisturisers
- Tinted SPF foundations
- Water-resistant sunscreens (with photostabiliser)
Mechanism of action
Absorbs UV via π-conjugated system electron transition in dibenzoylmethane chromophore. In ground state exists in enol-keto equilibrium; UV absorption converts to photoreactive diketone tautomer prone to photodecomposition. Photostabilisers prevent tautomeric shift via triplet energy transfer (Tinosorb) or quencher interactions (octocrylene).
Clinical evidence · High
Extensive in vivo UV protection data. Photostability fully characterised with co-stabilisers.
Effective concentration range
2–3% (US); up to 5% (EU)
Formulation notes
Critically photounstable standalone — degrades on UV exposure. Requires photostabiliser: octocrylene, Tinosorb S, Tinosorb M, or SolaStay S1. Incompatible with aminobenzoic acid derivatives.
Watchouts
Photodegradation products include reactive intermediates — argues for antioxidant co-formulation. FDA classified as insufficient data for GRASE due to systemic absorption above 0.5 ng/mL. TGA April 2025 review concluded low risk for typical face/hand application.
Conflicts with
Controversies & overclaims
FDA systemic absorption findings created clean-beauty backlash. TGA and SCCS concluded low systemic risk. FDA has not finalised its position. Characterisation as unsafe overstates current risk evidence.
Market positioning
Sold as the premier chemical UVA filter — technically accurate. Clean-beauty counter-narrative focuses on FDA GRASE status, a regulatory category not equivalently applied in EU or Korean markets.
Comedogenicity
0 / 5
Sensitisation risk
Low
INCI & aliases
Butyl Methoxydibenzoylmethane
butyl methoxydibenzoylmethane · parsol 1789 · escalol 517 · eusolex 9020
Clean beauty perception
Contested in US clean-beauty. Many brands moved to mineral-only SPF. European and Korean clean brands accept it more readily.
Related ingredients
Graph relationships
Timeline