Homosalate
It used to be in your sunscreen. Now it’s on The Watch List™.
A new Australian study has given us another reason to look a little more closely at homosalate, particularly when it comes to children.
Researchers tested urine samples from across Australia and found higher levels of UV-filter breakdown products in children than in older age groups.
For homosalate, the numbers really caught our attention.
Reef SunSafe® Category
Status: Failed
Junior Category SunSafe®
Status: Failed
What is Homosalate?
Homosalate is an organic UV filter.
It’s used in sunscreen to help absorb UV radiation and has been around for years.
It’s also still permitted for use in Australia.
But things are changing.
Homosalate is already being looked at by regulators here and overseas, with Australia’s TGA recommending tighter controls around how much can be used in therapeutic sunscreens. The European Union has also brought in tighter limits.
And now we have new Australian data looking at what happens after people use products containing it.
Something new just landed
Researchers looked at urine samples collected between 2012 and 2023.
There were 187 pooled urine samples, representing around 18,700 people.
They were looking for tiny traces left behind after the body processes several common UV filters.
And children stood out.
For the cis-form of homosalate:
80% of children’s samples were above the HBM-I level.
53% were above the HBM-II level.
From 2018 onwards, every children’s sample in the study was above HBM-I.
That’s a pretty big pattern.
The samples represented groups of people rather than giving us an individual result for every child. But the pattern was strong enough for the researchers to call for tighter controls around homosalate, particularly in products intended for children.
Wait. What’s a biomarker?
This is where the science sounds much more complicated than it actually is.
Researchers didn’t ask people to remember every sunscreen they’d used.
They looked at wee.
Yep. The kind you put in the little cup with the yellow lid when you go to the doctor.
A biomarker is simply something researchers can measure in the body that gives them a clue about what’s been happening inside it.
In this study, they measured substances in urine that are produced when the body processes UV-filter ingredients.
So instead of asking:
“Have you used homosalate?”
they could look for signs that the body had processed it.
That gives researchers a much better picture of exposure.
Why are children showing up?
The study found substantially higher UV-filter levels in children than in older age groups.
And this is where sun protection gets interesting.
We build a whole sun-protection system around kids:
Shade. Hats. Clothing. Sunglasses. Timing. Sunscreen.
Sunscreen is one part of that system.
For children who spend a lot of time outdoors, that can mean using it regularly and reapplying it often.
That’s exactly what we want people to do when the UV is high.
But it also means it’s worth knowing what’s actually in the products we’re putting on them again and again.
The researchers say the higher levels found in children may partly be linked to stronger sun-protection habits, including sunscreen use and Queensland school sun-protection policies.
So What’s the Science?
HBM-I and HBM-II are basically chemistry shorthand researchers use to make sense of what they find in human samples.
HBM-I
This is the level below which, based on current knowledge, health effects aren't expected.
HBM-II
This is the level where reducing exposure is recommended because the possibility of health effects needs a closer look.
They’re not sunscreen ratings.
They’re reference points that help researchers understand what they’re seeing in human samples.
And in this study, a lot of the children’s samples were above those reference points for the homosalate biomarker.
So why is Homosalate on The Watch List™?
Because this isn’t the first time people have started asking questions about homosalate.
Regulators have already been looking at it.
Australia’s TGA reviewed homosalate as part of its 2025 sunscreen safety review and recommended tighter controls on its use in therapeutic sunscreens. The TGA’s review looked at things including how much can get through the skin and the safety margin at different levels of use.
Overseas, the rules have already changed too.
The EU has moved to much lower permitted levels than Australia currently allows.
And now we’re seeing Australian human exposure data showing homosalate-related biomarkers at higher levels in children.
That’s worth taking a closer look at.
SunSafe® Says
✔️ Sunscreen still matters. UV exposure is a major risk factor for skin cancer, and sunscreen is one part of a good sun-protection system.
✔️ Children deserve particular attention. The study found substantially higher UV-filter biomarker levels in children than in older age groups.
❌ Homosalate is not currently on the SunSafe® Approved list.
The takeaway
Homosalate has been around for a long time.
But the conversation around it is changing.
We now have Australian research showing measurable exposure in the population, with children showing the highest levels and a large proportion of children’s samples sitting above health-based reference points for the cis-homosalate biomarker.
Combined with the regulatory changes already happening in Australia and overseas, that’s enough for Homosalate to remain on The Watch List™.
Is it better than getting sunburnt? Yeah.
Is it running through our bodies? We know that now.
The Watch List™
Homosalate is currently monitored by The Sunscreen List™ while the regulatory picture develops and the science continues to build.
Our approach is simple:
Know what’s in your sunscreen.
Know why it matters.
Then choose accordingly.
Want to see what made the cut?
Shop SunSafe® Verified Sunscreens →
References
Ebert, K. E. et al. (2026). Assessing UV Filter Exposure in Queensland, Australia: Human Biomonitoring Evidence Highlighting Homosalate in Children. Environmental Science & Technology. DOI: 10.1021/acs.est.6c09445.
Therapeutic Goods Administration (2025). Safety review of seven active sunscreen ingredients.
Therapeutic Goods Administration. Sunscreen ingredients.
European Commission, Scientific Committee on Consumer Safety (2021). Opinion on Homosalate.