It is bonkers that sunscreen (edit: SPF) testing still requires testing on a human subject, which makes testing both expensive and unreliable. Michelle Wong, who is quoted in the article as Lab Muffin Beauty Science, discusses it in more detail for a previous scandal, this one for a Korean sunscreen brand:
You’re kidding? You want millions of people to apply something that gets absorbed into the skin without testing it for side effects?
mitthrowaway2 · 2h ago
It's not side-effects that are in question here, it's the intended effect. When it comes to its effectiveness at blocking UV, there should be a better way than just "apply some to a dozen random volunteers and time how long it takes before they get a sunburn".
In my imagination, the lab would have some a testing process that spreads a precisely-controlled volume over a standard surface area, textured to be similar to skin, then measures UV transmission percentage vs wavelength with a diffraction grating and photocell. Or something like that!
chimeracoder · 1h ago
> In my imagination, the lab would have some a testing process that spreads a precisely-controlled volume over a standard surface area, textured to be similar to skin, then measures UV transmission percentage vs wavelength with a diffraction grating and photocell. Or something like that!
With this approach, how would you measure the effectiveness of the sunscreen when it's been absorbed by the skin (which is necessary for the sunscreen to work properly - that's why they always say to wait ten minutes after applying before going out into the sun)?
There's a reason in vitro and in vivo are both studied for clinical trials of medications. Sunscreen isn't any different: you're using a product making a specific claim about a clinical outcome, so that needs to be tested.
shermozle · 1h ago
I've actually been a test subject for sunscreen here in Australia. It involved having sunscreen put on different parts of your body, hopping into a Jacuzzi for an hour or so, then being zapped with UV on both sunscreened and clear skin.
Easiest hundred bucks I ever made, gotta say.
mcbain · 2h ago
The testing here is not just that it is safe on skin, but the SPF test itself is done by slathering it on humans and exposing them to light to determine a rating.
SapporoChris · 1h ago
You're kidding? You equate "not testing on human subject" to "not testing"?
kristianp · 2h ago
> "95% of the sunscreens tested [by Choice] have high enough SPF to more than halve the incidence of skin cancer," Dr Wong said.
I found this surprising; is halving the incidence of cancer enough to consider it safe? I would expect 90 or 95% reduction in the incidence of cancer to be considered safe.
Nursie · 2h ago
Yeah it’s not really enough.
The actual difference between (say) SPF 30 and 50 is not a lot, 96.7% UV filtering vs 98% but I’m not 100% sure how that translates to actual rates of cancer.
However the worst offenders in the testing advertised SPF 50 but delivered SPF 4 (~75% AFAICT)
andreareina · 2h ago
You can't compare the straight percentage, a 98% filter lets through twice as much as a 99% filter.
jandrewrogers · 54m ago
In both cases though the level of UV will be easily tolerated, which is the entire point. UV index is a linear scale, so more SPF has rapidly diminishing returns even in places with a UV index of 15+.
That the duration of protection is independent of SPF makes this particularly true. There are only a handful of places in the world where atmospheric conditions might give a very high SPF marginal benefits.
Nursie · 1h ago
True, so the important factor is - how does this map to your chances of getting skin-cancer?
DoctorOetker · 51m ago
The most reasonable answer is to look at the transmission percentage, not the blocking percentage.
dylan604 · 2h ago
But what about the sunscreen with ingredients that are carcinogenic before you even need to consider UV protection?
XorNot · 1h ago
Yes that would be serious so I suppose in an actual specific case regarding some specific real ingredients in products, we could discuss that.
jonahhorowitz · 1h ago
There have been cases of benzene being detected in sunscreen. It's not an intentional ingredient, just one that is common in industrial manufacturing. I don't think that's what the parent was worried about though.
No, benzene was specifically what I was thinking of to the point that I assumed it was so well known that it wasn't question as being a thing any more. Just like asbestos in baby powder
Nursie · 2h ago
I mean, that’s a whole separate question really. Alongside which constituents may be long-lasting and harmful to (for example) marine life.
cyberax · 33m ago
> The actual difference between (say) SPF 30 and 50 is not a lot, 96.7% UV filtering vs 98% but I’m not 100% sure how that translates to actual rates of cancer.
Counterintuitively, higher SPF matters a _lot_. The difference is in the _durataion_ of the protection and in the amount of sloppiness you can afford while applying the cream.
Suppose that for you the half-life for the sunscreen is 1 hour. SPF 30 cream would thus decay to SPF 7 in 2 hours, providing little protection. But an SPF 90 cream would still offer quite reasonable SPF 25 protection.
The same applies to sloppiness. SPFs are measured in perfect conditions, with a prescribed amount of the cream spread evenly. So the higher the SPF, the more mistakes you can make while applying it.
bawolff · 2h ago
> That rage grew when she learned the sunscreen she had been using for years was unreliable and, according to some tests, offered next to no sun protection at all.
If it wasn't working at all, wouldn't you notice getting sun burned?
Initially i thought it was going to be something advertised as spf 30 but actually 15. However spf 4 or less seems so low it should be noticable i would assume.
jandrewrogers · 2h ago
SPF doesn’t mean what people think it does. The level of protection is something like (1 - (1 / SPF)), such that the difference in marginal protection between SPF 15 and SPF 30 is literally only a few percent. While SPF 4 sounds “low”, it is already providing you 75% of the maximum possible protection.
The returns on protection are very much diminishing by SPF 30.
gruez · 1h ago
As others have mentioned, the difference between 75% (SPF 4) and 96% (SPF 30) might seem small, but the latter implies you can stay in the sun 7.5 times as long before getting sunburnt. That's significant. Moreover sunscreen rapidly loses effectiveness, so having "extra" protection might be worth it, especially if you don't reapply every 2 hours or after sweating/swimming, which what most sunscreens recommend.
jandrewrogers · 1h ago
The duration of protection is independent of SPF. There is no implication that you can stay in the sun longer with a higher SPF (FWIW, the packaging more or less makes this clear). The only thing SPF represents is a marginal reduction in total UV flux during the protected period.
Anything over SPF 30 buys you approximately no additional protection.
DoctorOetker · 31m ago
The instantaneous damage is directly inversely proportional to SPF.
Using no sunscreen is SPF 1 (at 2 milligrams per square cm).
Sunscreen SPF 2 would correspond to halving the rate of instantaneous damage.
SPF 30 compared to SPF 4 would indeed give (30/4)=7.5 times lower rate of instantaneous damage.
The SPF scale is more sensible than your blocking percentage scale.
DoctorOetker · 35m ago
What is of interest is not the blocking percentage, but the transmission percentage.
According to WikiPedia:
"For example, "SPF 15" means that 1⁄15 of the burning radiation will reach the skin, assuming sunscreen is applied evenly at a thick dosage of 2 milligrams per square centimeter[67] (mg/cm2)."
so assuming a linear dose response relationship (obviously oversimplified) when not using the sunscreen 15 times more instantaneous random damage is incurred compared to when using the sunscreen.
This does not translate directly into the rate of cancers though: just like the final damage of a meteorite storm isn't proportional, even though the instantaneous damage is.
Suppose a meteorite strikes a hospital, lots of damage. Then years later a meteorite strikes a school, lots of damage. Obviously if both happen in quick succession more damage will occur.
But if the whole human population takes up sunscreen use, selective pressure on cellular coping mechanisms will be relaxed, and eventually future generations won't be as resilient against sunburn. So just live your life, and don't allow scaremongers to separate you from your money, or thus indirectly scare you into doing your job for them.
bawolff · 1h ago
I mean, that is what i thought it meant.
So SPF 4 you are letting 25% of the sun through. I would assume that would be enough to still be sun burnt on a high uv index day if you spend most of it on the beach.
wahnfrieden · 2h ago
However across millions of people over lifetimes may offer substantial increase in incident reduction no?
willsmith72 · 2h ago
Sure but this is talking about n of 1
93po · 1h ago
what a tremendous failure on a regulation level
aplummer · 2h ago
Anecdata on QLD everyone knows banana boat is a scam. That sunscreen straight doesn’t work. The cancer council being on here is surprising though
According to the chart it's not even that bad? Sure, it underperformed its claimed SPF, but it's still above median.
aplummer · 51m ago
Yeah I think it’s the water resistance, I bet it way below par
Nursie · 42m ago
It works ok for me in Perth :shrug:
I use the spf 50 ‘sport’ version on my legs and arms (not the face, too greasy) and it seems to do the job OK.
I guess if it’s 35 in testing that’s still OK-ish for general use. I do really plaster it on. And as I’m usually doing that before a lot of outdoor work, it draws a further protective layer of sand and dirt to itself…
rayiner · 55m ago
Melanin is a real climatological adaptation. So are burqas.
BobbyTables2 · 2h ago
I’ve always felt sunscreen never lives up to its promise.
It’s tedious to apply thoroughly. It loses effectiveness with water, sweat, etc — inevitable when outside.
It would work best in indoor conditions but then wouldn’t be needed…
I suppose I could sun bathe on a cool winter day … but that just isn’t fun.
hilbert42 · 1h ago
"I’ve always felt sunscreen never lives up to its promise."
I agree with that for the same reasons. Nevertheless, I'll still use sunscreen when I have to. In Australia there are times when it's hard to avoid the sun but I avoid it at every opportunity.
If at the end of a day I feel my skin the slightest bit sore from exposure I know I've not been proactive enough.
richardw · 1h ago
In Australia here. I tend to go morning or 3pm. Crowds reduce, UV is lower, sun goes down 8pm in summer (so 3-8 is 5 hours). Anything near midday is silly.
andrewinardeer · 2h ago
What is also awful was the number of "influencers" aka digital door-to-door salespersons pushing that Ultra Violette sun screen slop on TT and Insta.
There is no repercussions for these clowns pushing a faulty product into the masses. I guess they actually are the winners here because they walk away with cash while their followers end up with shitty product and the company has to deal with the fallout. I doubt the digital door-to-door salespersons reputation suffers as their audience will still lap up anything they sell like a thirsty dog in the desert.
defrost · 1h ago
It's been 44 years since the original Slip, Slop, Slap! PSA campaign was launched on Australian TV and billboards.
> She says the scandal is a reminder that regulations are only as good as they are enforced.
I feel like we're going to be reminded of this a lot more in the coming years...
anonymars · 1h ago
<Twiddles moustache> These expensive, job-killing regulations are nothing but bureaucratic red tape! Vote for me and we'll give you back your freedom!
(Why must this work?)
contingencies · 2h ago
Everyone in Australia gets skin cancer. It's just normal. My grandma had something like 5 or 10 of them removed. In general, kids these days spend less time outside and do understand the value of hats and sunscreen or long sleeves, so it's getting better. The face can be hard, particularly without a hat.
I always laugh when people wear those stupid baseball caps instead of proper hats with brims. They think it's 'cool'. Mate, the main person laughing at your 'cool' is future you - dying from skin cancer on your face.
https://labmuffin.com/purito-sunscreen-and-all-about-spf-tes...
In my imagination, the lab would have some a testing process that spreads a precisely-controlled volume over a standard surface area, textured to be similar to skin, then measures UV transmission percentage vs wavelength with a diffraction grating and photocell. Or something like that!
With this approach, how would you measure the effectiveness of the sunscreen when it's been absorbed by the skin (which is necessary for the sunscreen to work properly - that's why they always say to wait ten minutes after applying before going out into the sun)?
There's a reason in vitro and in vivo are both studied for clinical trials of medications. Sunscreen isn't any different: you're using a product making a specific claim about a clinical outcome, so that needs to be tested.
Easiest hundred bucks I ever made, gotta say.
I found this surprising; is halving the incidence of cancer enough to consider it safe? I would expect 90 or 95% reduction in the incidence of cancer to be considered safe.
The actual difference between (say) SPF 30 and 50 is not a lot, 96.7% UV filtering vs 98% but I’m not 100% sure how that translates to actual rates of cancer.
However the worst offenders in the testing advertised SPF 50 but delivered SPF 4 (~75% AFAICT)
That the duration of protection is independent of SPF makes this particularly true. There are only a handful of places in the world where atmospheric conditions might give a very high SPF marginal benefits.
https://www.ewg.org/sunscreen/beware-of-benzene-shining-a-li...
Counterintuitively, higher SPF matters a _lot_. The difference is in the _durataion_ of the protection and in the amount of sloppiness you can afford while applying the cream.
Suppose that for you the half-life for the sunscreen is 1 hour. SPF 30 cream would thus decay to SPF 7 in 2 hours, providing little protection. But an SPF 90 cream would still offer quite reasonable SPF 25 protection.
The same applies to sloppiness. SPFs are measured in perfect conditions, with a prescribed amount of the cream spread evenly. So the higher the SPF, the more mistakes you can make while applying it.
If it wasn't working at all, wouldn't you notice getting sun burned?
Initially i thought it was going to be something advertised as spf 30 but actually 15. However spf 4 or less seems so low it should be noticable i would assume.
The returns on protection are very much diminishing by SPF 30.
Anything over SPF 30 buys you approximately no additional protection.
Using no sunscreen is SPF 1 (at 2 milligrams per square cm). Sunscreen SPF 2 would correspond to halving the rate of instantaneous damage.
SPF 30 compared to SPF 4 would indeed give (30/4)=7.5 times lower rate of instantaneous damage.
The SPF scale is more sensible than your blocking percentage scale.
According to WikiPedia:
"For example, "SPF 15" means that 1⁄15 of the burning radiation will reach the skin, assuming sunscreen is applied evenly at a thick dosage of 2 milligrams per square centimeter[67] (mg/cm2)."
so assuming a linear dose response relationship (obviously oversimplified) when not using the sunscreen 15 times more instantaneous random damage is incurred compared to when using the sunscreen.
This does not translate directly into the rate of cancers though: just like the final damage of a meteorite storm isn't proportional, even though the instantaneous damage is.
Suppose a meteorite strikes a hospital, lots of damage. Then years later a meteorite strikes a school, lots of damage. Obviously if both happen in quick succession more damage will occur.
But if the whole human population takes up sunscreen use, selective pressure on cellular coping mechanisms will be relaxed, and eventually future generations won't be as resilient against sunburn. So just live your life, and don't allow scaremongers to separate you from your money, or thus indirectly scare you into doing your job for them.
So SPF 4 you are letting 25% of the sun through. I would assume that would be enough to still be sun burnt on a high uv index day if you spend most of it on the beach.
I use the spf 50 ‘sport’ version on my legs and arms (not the face, too greasy) and it seems to do the job OK.
I guess if it’s 35 in testing that’s still OK-ish for general use. I do really plaster it on. And as I’m usually doing that before a lot of outdoor work, it draws a further protective layer of sand and dirt to itself…
It’s tedious to apply thoroughly. It loses effectiveness with water, sweat, etc — inevitable when outside.
It would work best in indoor conditions but then wouldn’t be needed…
I suppose I could sun bathe on a cool winter day … but that just isn’t fun.
I agree with that for the same reasons. Nevertheless, I'll still use sunscreen when I have to. In Australia there are times when it's hard to avoid the sun but I avoid it at every opportunity.
If at the end of a day I feel my skin the slightest bit sore from exposure I know I've not been proactive enough.
There is no repercussions for these clowns pushing a faulty product into the masses. I guess they actually are the winners here because they walk away with cash while their followers end up with shitty product and the company has to deal with the fallout. I doubt the digital door-to-door salespersons reputation suffers as their audience will still lap up anything they sell like a thirsty dog in the desert.
https://www.youtube.com/watch?v=b7nocIenCYg
Revised & updated in 2010: https://www.youtube.com/watch?v=FzA47J7QsVkI feel like we're going to be reminded of this a lot more in the coming years...
(Why must this work?)
I always laugh when people wear those stupid baseball caps instead of proper hats with brims. They think it's 'cool'. Mate, the main person laughing at your 'cool' is future you - dying from skin cancer on your face.
"Mad dogs and Englishmen go out in the midday sun." - https://www.phrases.org.uk/meanings/mad-dogs-and-englishmen....
https://www.sunsafeaustralia.com.au/headwear/p/uveto-austral...
https://hendersonvilleoutfitters.com/products/upf-shirts