Walk into a pharmacy in Europe, or Japan, or Australia, and you’ll find a sunscreen ingredient that protects your skin from the signs of aging better than anything sold in the United States — and it doesn’t have the absorption safety questions that hang over other sunscreen ingredients.
It’s been on shelves overseas since the 1990s. Americans have flown home from holidays with suitcases full of it.
Because until a few weeks ago, you effectively couldn’t buy it in the US. Not because anyone found it dangerous — but because of an unintended consequence of a decision made back in 1938. Here’s how that happened, and what just changed this month that finally gave Americans access to it.
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What America was locked out of
The thing in the suitcases that Americans brought back from their overseas holidays has a name: bemotrizinol.
It’s a sunscreen filter — one of the chemicals that actually does the work of soaking up the sun’s rays before they hit your skin, protecting you from photoaging. And it does two things that, until now, you couldn’t get together in one bottle in America.
The first is that it doesn’t pass from your skin into your bloodstream. To see why that matters, you need to know what the alternative does.
There are two kinds of sunscreen filters. The mineral ones — zinc oxide and titanium dioxide — mostly sit on top of your skin [1]. And the chemical ones — names like avobenzone, oxybenzone, octocrylene — soak in. The chemical ones are in most of the bottles on the shelf, because they go on nicer and rub in clear.
But here’s the part that surprises people. The FDA ran its own studies on those chemical filters to see how they behave on the skin. Worryingly, the filters didn’t stay on the skin — they crossed into the bloodstream, past a level the FDA uses to decide whether a chemical needs the full battery of long-term safety studies. Several crossed it on day one [2].
I want to be clear: this doesn’t mean those products are dangerous. The FDA’s point is that higher absorption means higher potential impact, and that means we need a higher standard of evidence to be sure the chemicals are safe — evidence we don’t yet have [2]. The FDA’s own advice is to keep using sunscreen while that data gets sorted out.
But I don’t like to be routinely rubbing something into my skin when the data is incomplete. And that’s the honest reason I’ve leaned, for myself, towards filters that don’t soak in.
Bemotrizinol is one of those filters, and the reason it barely absorbs isn’t magic — it’s mostly just size. Most chemical filters are small molecules, small enough to slip between your skin cells and work their way down into the bloodstream, which is exactly what those FDA studies caught them doing. Bemotrizinol is a giant by comparison — its molecular weight is about 628, more than twice the size of a filter like oxybenzone at 228 [3][4].
And there’s a well-known rule of thumb in skin science: once a molecule gets much heavier than about 500, it simply can’t push through the outer layer of your skin. Bemotrizinol is well past that line [5].
There are two other key features. For one, it provides protection from the deep rays — the long-wave UVA that ages your skin and that a lot of US “broad spectrum” products quietly under-block. Independent testing of sunscreens on the US market found the average UVA protection factor was just 24% of the labeled SPF [6]. Bemotrizinol, marketed by BASF as Tinosorb S, covers the entire UVB and UVA range, with absorption peaks around 310 nm and 340 nm — the wavelengths most responsible for skin damage and premature aging [7].
And it keeps working in the sun rather than breaking down the way some older filters do. That photostability is bemotrizinol’s other advantage — it holds up in sunlight so well that it’s actually used to stop other, flimsier filters from falling apart [8].
So unlike the minerals, it rubs in clear, holds up better in water, and covers the full range. It’s the rare filter that gives you the stay-on-the-surface behaviour of a mineral with the feel and protection of a chemical. And it’s not experimental — it’s been used safely all over the world for about twenty-five years. Europe approved it back in 1999 [9].
Which raises the obvious question. If it’s this good, and it’s this old — why on earth couldn’t Americans actually buy it until 2026?
Why America waited twenty years
The answer is not what you’d expect. In the United States, sunscreen is legally a drug. It goes back to a law from 1938 — the logic being that sunscreen “prevents disease,” so it sits in the same regulatory bucket as medicine. And to get a new drug ingredient approved, you need clinical safety and effectiveness data, and you need the FDA to clear it before it can go on sale [10].
Everywhere else — Europe, Australia, Asia — sunscreen is a cosmetic. And a cosmetic has a faster path: the company itself is responsible for showing its ingredient is safe, and it can bring it to market without that drug-style pre-approval [10]. That one difference — drug versus cosmetic — is the whole story.
And the cost of that one difference is staggering when you see it laid out. The United States went from 1999 all the way to 2026 — over a quarter of a century — without approving a single new sunscreen filter [11].
Bemotrizinol itself was first filed with the FDA back in 2005. And it wasn’t alone — it was one of a row of new filters that all got submitted and then just sat there. Eight other companies were in the same boat, some pending for more than a decade with no decision either way [11].
By 2014, this had become enough of an embarrassment that Congress actually stepped in. They passed a law called the Sunscreen Innovation Act, designed to force the FDA’s hand — review the backlog, hit hard deadlines, make a decision [11].
And here’s the twist. The law worked, in the narrow sense that it forced the FDA to act. But the action they took, in 2016, was to lay out fresh requirements for sunscreen ingredient approval — requirements that meant lengthy clinical trials costing millions. A law built to speed things up produced a fresh round of “come back with more evidence.” As one industry figure put it: “Nobody did anything because it was way too expensive.” [11]
Three years later, in February 2019, the FDA issued an important update. Of all the sunscreen ingredients, only two — zinc oxide and titanium dioxide, the minerals — were recognized as both safe and effective. The twelve common chemical filters then on the market all landed in a “we need more data” pile [12][2].
And then the FDA’s own scientists ran the absorption studies — the ones I mentioned at the start, where the older filters crossed that 0.5 ng/mL line. We now had more data. And instead of expanding the options on the market, it threatened to shrink them even further.
One bit of fairness about how those absorption tests were run, because it matters: they represented the worst-case scenario, on purpose. Sunscreen was applied over 75% of the body, four times a day, for four days in a row [2]. So in everyday use, the amount getting into your blood is lower than those headline numbers. The point stands that it gets in — but it’s a matter of not knowing the effects, which is very different from knowing there are actual harms.
So how did the logjam finally break? In 2020, buried inside the CARES Act — a law aimed at pandemic relief — Congress scrapped the slow old process for these over-the-counter products and replaced it with a faster one. And crucially, it added a reward: a company that does the expensive work of generating the data for a brand-new filter gets a window of exclusivity to sell it. That gave a company both a faster route and a real reason to spend the money [11].
The company that makes bemotrizinol, DSM-Firmenich, took that deal. They spent years and roughly $8 million generating exactly the data the FDA had been demanding, then paid the $537,000 filing fee on top [11]. And that’s what finally carried bemotrizinol across the line, on June 9th, 2026. It doesn’t take effect until August 9th, though — the ingredient is cleared and the products are coming, but if you live in the US, they won’t be on your shelves until summer is almost over [13].
So what about in the meantime? If you specifically want to avoid filters that make it into your blood, you already have an option on the shelf today: the minerals, zinc oxide and titanium dioxide. They stay on the surface. The trade-off is the white cast they can leave, which is worse on deeper skin tones.
So: sunscreen every morning, and then retinoid creams at night. Retinoids also strengthen the skin’s protective barrier, reduce water loss, and slow the enzymes that break down the skin’s support structure.
The oldest and most widely studied is tretinoin. It was first used to treat acne, but patients soon noticed it seemed to improve the appearance of skin in general — even the signs of aging — and it was approved by the FDA for that purpose. One massive review that looked at 180 individual studies reported that topical tretinoin improved the signs of photoaging — wrinkling, uneven coloration, and age spots — in as little as one month of use [14].
Though it works really well, some people are sensitive to tretinoin — skin irritation, redness, and dryness, especially at first. That drawback led to newer, third-generation retinoids like adapalene, which cause less irritation. But does that mean sacrificing effectiveness? A head-to-head trial in 2018 set out to test exactly that, and concluded adapalene 0.3% gel was non-inferior to tretinoin 0.05% cream for photoaged skin, with a similar safety profile [15].
And in addition to sunscreen in the morning, retinoids at night, a good diet, regular exercise, and high-quality sleep, two supplements have shown promise in human clinical trials.
The first is hyaluronic acid — the molecule your skin uses to hold onto water, and which you lose as you age. In a randomised, placebo-controlled trial, people taking 200 mg a day of oral hyaluronic acid saw measurably better skin hydration (+10.6%) along with shallower wrinkles (depth −18.8%, volume −17.6%) and a small increase in elasticity and firmness, over 28 days [16].
The second is collagen. A 2023 meta-analysis pooled 26 randomized controlled trials, involving 1,721 people, of collagen peptide supplements, and found they significantly improved skin hydration and elasticity compared with placebo [17].
Now, even if we’ve worn sunscreen as recommended from the time we were kids, a certain amount of skin aging is inevitable. But there are more ways to counter it than ever before — many of them cheap or even free.
References
1. https://onlinelibrary.wiley.com/doi/10.1111/phpp.12439
2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6549296/
3. https://pubchem.ncbi.nlm.nih.gov/compound/Bemotrizinol
4. https://pubchem.ncbi.nlm.nih.gov/compound/4632
5. https://onlinelibrary.wiley.com/doi/10.1034/j.1600-0625.2000.009003165.x
6. https://onlinelibrary.wiley.com/doi/10.1111/phpp.12738
7. https://www.basf.com/us/en/media/news-releases/2026/06/P-US-26-27
8. https://pubmed.ncbi.nlm.nih.gov/11594052/
11. https://beautymatter.com/articles/the-great-sunscreen-odyssey
12. https://www.govinfo.gov/content/pkg/FR-2019-02-26/pdf/2019-03019.pdf
14. https://pmc.ncbi.nlm.nih.gov/articles/PMC9112391/
15. https://pubmed.ncbi.nlm.nih.gov/30105991/
