Skip to content

Sunscreens in the news: The Spray-on Banana Boat Case

November 29, 2017

Last week brought us news that a range of Banana Boat spray on sunscreens (aerosols) were being taken to court for allegedly failing to deliver the level of protection that they promised.  Apparently the aerosols in question had been re-tested by a lab here in Australia (we now only have one – Eurofins which used to be Dermatest, based in Sydney) and found to fall way short of their advertised SPF – achieving an average across the seven products of SPF 16.5 while advertising an SPF of 50 which actually requires the product to return a reading of SPF 60 in lab conditions.

                     Picture from CHOICE magazine. 

According to the article the testing was carried out on 10 samples of each product using the ISO 24444 standard and that’s where I think things start to get interesting as this test method is a new(ish) harmonised standard that reports to be equivalent to the FDA standard but based on what I understand of the FDA standard the subtle differences within it are important.

Here is a sheet from Dermatest about ISO 24444 and a presentation outlining the roll out of this standard and how it compares with others. 

A few years back I was spending a lot of time at a sunscreen testing lab, testing subjects and generally gaining a better understanding of how things worked in the SPF testing world. This was the same time that changes to the SPF testing method were being implemented with one step being a ring study. A ring study involves a number of sunscreen testing labs agreeing to test a set range of sunscreens using the proposed new method then comparing results with an aim to iron out any inconsistencies between labs.  Inconsistencies between labs were not (and are still not) uncommon as not everything in the SPF testing method is water-tight and this is where I think the lawyers might start to have a field day.

Let’s go back to one of the ring studies that was being conducted to form the basis of this ISO change. A ring study that involved APTF and Dermatest here in Australia.

The study is reported here.

The ISO sunscreen standard contains a reliance on a particular way of accounting for UVA radiation and a thing called ‘critical wavelength’.  The higher the SPF, the more the quality of the sun protection on offer matters.  This particular ring study was looking to validate the UVA radiation evaluation method. According to this paper they summarised ‘The data demonstrate convincingly that the in vitro determination of the UVA protection of sunscreens can be performed in a very reproducible manner’ which, after reading the results and comparing that with what I knew was going on at the time in terms of concerns raised and conversations had makes no sense to me.   I have to admit that I don’t have a crystal clear way of explaining what I think is wrong with this piece of the ISO standard pie but I can tell you it is erring towards the fact that this UVA determination step does make me feel uneasy, like it isn’t quite as robust and reproducible as we are being told.  My niggling on this point comes from two places, and I’ll be honest here, Gavin Greenoak who I worked with had lots of issues with this UVA based change to the standard, so much so that he continued to tell customers something along the lines of ‘if they want to pass a sunscreen test go with the ISO but if they want to know how good their product was use the Australian standard’ (my interpretation of what he’d said to me during conversations).  We discussed the proposed changes often and while I have to admit to having only a tiny fraction of the understanding that Gavin had, I accepted and understood that using  In-Vitro data  to inform or interpret a In-Vivo result made no sense at all.

UVA isn’t actually a discrete thing and the calculation of a ‘critical wavelength’ is, at best, a compromise. Think of it like a rainbow. If you try and chop the blue out of the rainbow where do you start and finnish the chopping?  A rainbow’s colours blend into one another seamlessly and if you take one colour out you are not left with a rainbow with no blue, you are left with something that isn’t a rainbow by any definition of the word. We know from photobiological studies that if we irradiate a living thing with discrete portions of the UV spectra we change the quality of light and, in effect, transport that living thing onto another planet – life has evolved with a full spectrum of light and not chopped up bits of this or that.   This ISO 24444 first step is not a people test, it is based on a machine evaluation.  Sunscreen is placed onto a synthetic skin and measured.   You might be surprised to hear that there are options of which synthetic skin you go with.  The ISO method does specify a type of synthetic skin but the question still remains ‘is this the right one?’  Now Gavin was working on a substrate called Mimskin at the time and Mimskin was not the synthetic skin that ISO approved so I am open to their potentially being some bias against the Plexiglas that was chosen but nevertheless it does raise a few important questions.  Keeping in mind that we are about to perform a test on a skin substitute to calculate a UVA figure that will then form the pivot point for our SPF results we need the skin to be as skin like as possible. This is because a sunscreen is a filter and how that filter applies makes ALL the difference.  Human skin is full of peaks and troughs and these vary greatly between people and even between skin sites on the same person.  If the synthetic skin chosen has less peaks and troughs than typical human skin it could, theoretically, return a higher SPF in the test than it does in person. Because of that a smoother ‘fake’ skin would potentially enable higher SPF readings which might be favourable from a marketing perspective but if it can’t be replicated in person is there any point?  It seems very important for the synthetic skin to at least behave in a way relatable to human skin in terms of how it allows sunscreen to spread and where the sunscreen lies and how it covers.    I feel there is still more work to be done here with respect to whether the skin substrate is as good as it could be given that we are placing so much weight in it.  Here is a link to an interview Gavin did about his Mimskin.   and here is a link to a press release put out by Cosmetics Europe about the ISO method.

and another press release in 2013 here.

But that’s not the only issue with SPF testing…..

Inconsistencies between labs were not unusual as while the amount in grams of sunscreen per bit of skin has been a set-in-stone protocol for a long time, the actual method of application to the skin does make a difference and different operators at different labs used different methods to apply the product.  I’m talking rubbing in vs placing, how many times you pass the product over the skin etc.  I’m also talking about how the product gets from the measuring jar to the skin – via nude or coated finger? The FDA method specifies a fingercot has to be used whereas the ISO method does not, thus opening up a whole world of variability that need not exist.

Skilled operators with years of experience have their own way of keeping things consistent whereas staff with less experience may not appreciate the need for a steady, consistent application that doesn’t vary from product to product.  While none of this is directly relevant to the layperson buying and using the product (the lab technician won’t be joining you on the beach to ensure a good application) it does mean that SPF levels across different products are comparable.

So what does this mean for Banana Boat?

Well this is difficult to know and I guess this is what the legal proceedings will try to unpick but how they will do that without unpicking the test method is a bit of a mystery to me.  The points that Gavin made during his lifetime about how poor this new standard was were not popular to the point of being largely dismissed. I found this a shame as Gavin was one of the few true scientists and passionate enthusiasts for understanding things on a pure level that I’ve ever met and I do really miss having him around to talk about this sort of thing to.   I know that some of the opposition for Gavin’s views came from the fact that he was taking on the establishment so to speak – standing up and asking questions, asking for evidence, asking for proof among.  As we have so recently seen with the sex scandals in Hollywood and even Australia now, breaking the seal in a profession, asking the tough questions, saying it how you feel it is is not something that goes down well and can often be squashed, sometimes for years.   On the other hand maybe Gavin’s views were unpopular because he was just wrong, barking up the wrong tree, had his own axe to grind and money to make and wasn’t being positioned to capitalise…..  While I was Gavin’s friend, I was his friend because we could discuss and debate things, I wasn’t about to blow smoke up his arse when I thought he was completely wrong and now he’s dead so why shouldn’t we just have one more look into what he was trying to say? He can’t profit now (and neither can / would I).

And back to Banana Boat.

I think it will be impossible for the Banana Boat case to not evaluate the test method in order to establish what is going on.  I know that Banana Boat do test their sunscreens thoroughly and properly and can’t see why they would take the risk of labelling an SPF 16.5 product as an SPF 50 product knowingly so something has gone wrong here, something has failed but is the failure the test method, the lab, the formula or the packaging or something else?

These products were all aerosol type sunscreens so while I’ve banged on about the SPF test method it is also valid to look at the capacity of an aerosol to deliver a consistent and stable SPF 50.  The reason I haven’t banged on about how hard aerosols are to apply and the dangers of aerosol SPF products here is because of the lab based SPF results issue.  A person just getting burned after using a sunscreen could mean they didn’t apply enough or often enough or that they had a reaction to the formula or that the product was out of shelf life or some other issue.  Ridiculously low SPF results in an in-date and properly applied sunscreen is something else entirely.

The bottom line here is that we need sunscreens to work.  While it is possible for many of us to screen ourselves from incidental sun via clothing, sun avoidance behaviours and an antioxidant rich diet (yes it can help but not by much) and good hydration there are times when only a sunscreen will do.  The Banana boat case could further fuel moves by some areas of the public to shun protection altogether or worse, make their own un-tested sunscreens from internet recipes – I say this is worse as at least with no sunscreen you modify your behaviour and are under no illusions when you burn, a home-made sunscreen can lead to a false sense of security and adoption of less cautious behaviour.

I will be watching this case very carefully to see what direction it takes and keeping my fingers crossed that the case does get to the bottom of what is a very worrying situation.  I am happy to admit that I might be completely wrong to suspect that the problems start with the test method but the bottom line is that I just want sunscreens to work and for me, faith in the process starts with having faith in the test method.

Amanda x

PS: Just to finish off, if you are new to SPF or want a refresher on how sunscreens work this article is a very good place to start.


3 Comments leave one →
  1. peanut permalink
    November 29, 2017 10:20 pm

    My own sunscreen update: after a few rounds of emails back and forth, Galdmera told me they have discontinued both the Actinica sunscreen and the Cetaphil Suntivity Liposomal sunscreen in Australia due to “commercial reasons”. Now what’s that supposed to mean, commercial reasons? I then took the risk and ordered Actinica online from the UK which i managed to get one.

    • RealizeBeautyEd permalink*
      December 1, 2017 6:22 am

      Hi there,
      Commercial reasons probably mean just that. If items aren’t selling well they will be discontinued as it becomes impractical and expensive to support a failing product. Australia is such a funny, fragmented market so it never surprises me when things disappear from here. I think buying it from overseas is a good idea. Stock up and enjoy 🙂

      • peanut permalink
        December 4, 2017 9:48 pm

        I actually bought another sunscreen over the weekend, just out of curiosity. It’s actually a good replacement for Actinica. It’s called Skinstitut Age Defence SPF 50+. It also contains very high amounts of Tinosorbs and other actives just like Actinica. I don’t need to panic now, i have options.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: