Sun protection · Reference
Bemotrizinol and hair extensions: what the new sunscreen ingredient fixes, and what it doesn't
The first new sunscreen ingredient approved in the United States in nearly thirty years is a genuinely good one. It is also being widely misread as the end of sunscreen staining on hair extensions. It isn't — and the reason is worth understanding before your clients start asking.
Where this stands today
- FDA approved
- 9 June 2026
- Permitted in US products
- 9 August 2026
- Expected on shelves
- Late 2026, first as Parsol Shield
- Available to other brands
- After an 18-month exclusivity period
Last reviewed 26 July 2026 · This page is updated as the rollout progresses
The short answer
Bemotrizinol does not stain hair extensions — it has no structure that can react with extension color. But it doesn't replace avobenzone, which is the ingredient that causes staining. Most formulas will use both, because bemotrizinol makes avobenzone more stable. So check the active ingredients on any sunscreen before you use it, and until then, mineral is still the reliable choice.
What to use instead, today
Turn the bottle over. Under Active Ingredients, you want to see zinc oxide, titanium dioxide, or both — and nothing else. That's the whole test.
Zinc oxide and titanium dioxide are stable, insoluble mineral particles. They release no free ions and have no structure capable of reacting with the dye in hair extensions; they sit on the surface and rinse away. Of the two, zinc oxide holds its protection further into the long UVA range, so a zinc-only or zinc-dominant formula is the stronger choice.
This does not change when bemotrizinol reaches shelves. It changes on the day a bemotrizinol sunscreen arrives with no avobenzone in it — and we will name it here when one does.
What bemotrizinol actually is
Bemotrizinol — you may see it as bis-ethylhexyloxyphenol methoxyphenyl triazine, or under the trade names Parsol Shield and Tinosorb S — is a chemical sunscreen ingredient that has been in use across Europe, Asia and Australia since around 2000. It absorbs across both UVB and UVA, holds up unusually well in sunlight rather than degrading, and leaves no white cast.
Its approval matters because the United States has been working with a short list. Until now, avobenzone was the only non-mineral ingredient approved here that reaches deep into UVA — which is precisely why it turns up in so many formulas, and why staining on hair extensions has been so difficult to avoid.
Reference
What each sunscreen ingredient absorbs
Every approved US sunscreen ingredient, plotted against the wavelengths it protects against — and marked for how it behaves around extensions.
Wavelength (nm)
Coverage
Reading the chart
Around extensions
† Octinoxate is a genuine avobenzone co-formulant — DSM lists it among the approved solubilizers for Parsol 1789 — although it is a poor photostabilizer, since the two degrade one another under UV. It earns its place on the avoid list.
‡ Bemotrizinol has no staining structure of its own, but at the 6% US cap it does not reach the broad-spectrum threshold alone.
Ranges reflect published absorbance spectra for each ingredient. Regulatory status per FDA OTC Monograph M020. Frame & Thread, 2026.
Why it isn't the fix everyone is hoping for
Three reasons, and they compound. The first is a matter of physics, the second is a matter of incentive, and the third is simply what already happens in the markets that have had this ingredient for two decades.
It doesn't reach broad spectrum on its own
Bemotrizinol's absorbance peaks at roughly 310 and 340 nm. Because so much of its curve sits in UVB and mid-UVA, it falls short of the 370 nm critical wavelength the FDA requires for a broad-spectrum claim — particularly at the 6% concentration cap the US has set. BASF's own guidance to formulators is to combine it with zinc oxide or avobenzone to clear that threshold.
It is an unusually good avobenzone stabilizer
Avobenzone's long-standing weakness is that it breaks down in sunlight, losing much of its protection within the first hour. Bemotrizinol is exceptionally stable and will absorb that excess energy before avobenzone can degrade. The FDA's own scientific review notes this stabilizing effect. For a formulator, that is a powerful argument to add bemotrizinol to an existing avobenzone formula — not to remove the avobenzone.
Abroad, that pairing is already the norm
This isn't a prediction. In Europe and Australia, where bemotrizinol has been available since around 2000, it is routinely formulated alongside avobenzone precisely because the combination is more stable than either alone. There is no reason to expect the American market to behave differently — and every reason to expect brands to reach for it as an upgrade to formulas they already produce.
Which leads to the practical conclusion: a product containing bemotrizinol may or may not also contain avobenzone, and the only way to know is to read the active ingredients. "Now with bemotrizinol" on the front of a bottle tells you nothing about whether it is safe around hair extensions.
What actually stains hair extensions
Avobenzone, and — as far as the chemistry supports — avobenzone alone. Its structure lifts the bound metal ion out of the specialty dye used to color hair extensions. That single event does two things at once: it disrupts the color that was there, and the freed ion, now attached to the avobenzone, deposits as a new peachy-orange compound. It is a stubborn stain, and it is why natural hair doesn't do this — there is no embedded ion for the avobenzone to take.
This is not mineral buildup, and it is worth being precise about the difference. Iron and copper from hard water, well water or pool systems also stain hair — that is a real problem, but a separate one, and it is fixed by treating the water. Avobenzone staining does not work that way. The metal it takes is not sitting on the outside of the hair; it is the ion built into the dye itself, put there deliberately during manufacturing to make the color hold. That is why this happens in soft water, in filtered water, and in the ocean, and why no amount of water treatment prevents it. The only thing that prevents it is keeping avobenzone off the hair.
The full mechanism, and what can be done once it has happened, is covered in our guide to fixing stained and discolored extensions.
What to tell your client
At the chair
Language you're welcome to borrow, adapt, or send as-is.
"There's a new sunscreen ingredient coming this year — it's a good one, but it doesn't replace the ingredient that stains your extensions. Keep checking the label."
"You might hear about bemotrizinol — it's the first new sunscreen ingredient approved in the US in almost thirty years, and it's genuinely better than what we've had. It won't stain your hair.
But it isn't a swap for avobenzone, which is the ingredient that causes the peachy-orange staining. Most formulas will use both together, because the new one actually helps the old one work better. So a bottle can advertise bemotrizinol on the front and still have avobenzone inside.
Nothing changes for you right now: check the active ingredients, and if avobenzone is listed, pick something else. Zinc oxide or titanium dioxide on their own is still the safest choice."
"Not for a while. It's approved, but products won't reach shelves until late this year, and only from one brand at first. Realistically it'll be 2028 before it's in everything — so don't wait on it."
How to read a sunscreen label
Sunscreens have two ingredient lists. The one you want is the short one, headed Active Ingredients, usually on the back. By law it sits on its own, and it is the only place these sunscreen ingredients appear.
- Avobenzone — this is the one that stains.Also appears as: butyl methoxydibenzoylmethane
- Octisalate, homosalate, octocrylene, oxybenzone. Not causes in themselves, but they dissolve and stabilize avobenzone, so their presence is a strong sign it is in the formula too.Also appears as: ethylhexyl salicylate, benzophenone-3
- Bemotrizinol. Safe on its own. Tells you nothing about what else is in the bottle.Also appears as: bis-ethylhexyloxyphenol methoxyphenyl triazine, Parsol Shield, Tinosorb S
- Zinc oxide, titanium dioxide. Stable mineral particles that cannot interact with hair extension color at all — they release no free ions and sit on the surface until they rinse away. A sunscreen listing only these is the safest choice available today.
Parsol Shield is not Parsol 1789
This one is going to cause trouble. "Parsol" is not an ingredient — it is DSM's entire family of sunscreen ingredients, and five of the six on our avoid list carry a Parsol name. The word on its own tells you nothing until you read what follows it.
| Trade name | Ingredient | Safe around extensions |
|---|---|---|
| Parsol 1789 | Avobenzone | No — this is the one that stains |
| Parsol 340 | Octocrylene | Avoid |
| Parsol EHS | Octisalate | Avoid |
| Parsol MCX | Octinoxate | Avoid |
| Parsol HMS | Homosalate | Avoid |
| Parsol Shield | Bemotrizinol | Yes — but check what else is in it |
Bemotrizinol is Parsol Shield. Avobenzone is Parsol 1789. For our purposes they are opposites, and they are separated by one word on a spec sheet.
BASF sells the same molecule as Tinosorb S — the name it has carried in Europe, Asia and Australia since 2000, and the one your clients may already know from imported sunscreens. Parsol Shield and Tinosorb S are the same ingredient.
One more thing, and it will save you an argument. Parsol Shield is what a sunscreen manufacturer buys; it is not what will be printed on the bottle. US labeling rules require the active ingredients to be named the standard way, so what you will actually read is bemotrizinol — occasionally its full chemical name, bis-ethylhexyloxyphenol methoxyphenyl triazine. Expect "Parsol Shield" on the front of the pack as a marketing flag, if at all. Press coverage has already blurred the two, to the point that Consumer Reports published a correction over it. Look for bemotrizinol in the active ingredients.
What we'll update, and when
Frame & Thread supplies licensed cosmetologists and salons. This page is written for professionals and is informational, not medical or regulatory advice.
Sources: FDA OTC Monograph M020 and the supporting scientific review for order OTC000039; BASF product guidance for Tinosorb S; Chatelain & Gabard, Photochemistry and Photobiology, 2001. Published 26 July 2026.
