Tinosorb S Is Coming: What the FDA's New Filter Means for You
Bemotrizinol's moment is almost here.
Tinosorb S and Tinosorb M have been used in Europe, Asia, and Australia for over two decades.
Bemotrizinol is broad-spectrum and so photostable it retains roughly 98% of activity after intense UV exposure.
Frequently asked questions
Why are some UV filters more photostable?
A photostable filter keeps absorbing UV without breaking down in sunlight. Older filters like avobenzone can lose protection within an hour unless paired with stabilizers such as octocrylene. Next-generation filters are engineered to stay chemically stable, so protection lasts longer — though reapplication is still advised.
What is the difference between Mexoryl SX, XL and 400?
All three are L'Oréal/BASF UVA filters. Mexoryl SX (ecamsule) covers shorter UVA; Mexoryl XL (drometrizole trisiloxane) is broad-spectrum and oil-soluble; and Mexoryl 400 (MCE) targets ultra-long UVA1, peaking around 385 nm — the deep wavelengths most older filters miss.
What is bemotrizinol (Parsol Shield)?
Bemotrizinol (trade name Parsol Shield; also known as Tinosorb S) is a broad-spectrum UVA+UVB filter that is highly photostable. On June 9, 2026 the FDA approved it — the first new sunscreen active added to the US monograph since the 1990s — for adults and children 6 months and older at up to 6%.
r/SkincareAddiction: 'Is bemotrizinol finally coming to US sunscreens?'
Sources & citations
- Holland & Knight, 'FDA Proposes First New Sunscreen Ingredient in Decades' (Dec 2025)
- hklaw.com ↗