My list of good and bad sun filters
I wrote in a recent blog about how, in combination with the sun, quite a few ingredients in skincare products can cause irritating skin rashes. But did you know that certain sun filters can even cause problems under the influence of sunlight? It is a strange world. Does your skin suddenly become sensitive in the sun? Then you should check the ingredients list on your own (sun cream) products.
It is a known fact that some filters are more likely to cause an allergic reaction than others. And as multiple filters are used in most sun cream products it can be quite a challenge to track down the culprit and subsequently find a suitable product that your skin reacts well to. Sometimes you will have had to try out three or four products. And then, of course, you would like a filter which offers the very best protection. Do all filters do the same thing?
Red, green and yellow light for these filters
In order to give you some assistance with this search I have made a summary of the most popular sun filters used in Europe. I have separated these into ‘good’, ‘possible’ and ‘best avoid’. I have based this on available scientific papers. An important consideration in this grouping is whether I would want to apply the ingredients onto my children’s skin.
I would use the ‘good’ filters without any hesitation. I would only use the ‘possible’ filters if I don’t have to use them daily. I would rather not use the sun filters in the category ‘best avoid’- unless I was living on a deserted tropical island with no alternative for me. As protecting yourself with a lower quality sun filter is still better than incurring unprotected sun damage!
For the interested users: you can also find, among other things, the studies that I have used for the categorising of all sun filters in this other table (in Dutch).
Filters which I trust completely to put on my own skin and that of my children.
Inci: Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine
- Definition:One of my favourite filters. Protects against both UVA and UVB, does not absorb into the body, is not hormone disruptive, little risk of irritation, not free radical forming and features anti-inflammatory properties. Research has also shown that this filter absorbs UV as well as eliminating free radicals, making it an all in one sun filter with an antioxidant action.
Inci: Methylene Bis-Benzotriazolyl Tetramethylbutylphenol (nano)
- Definition:The term nano may shock you. Quite a bit has been written and discussed about nano particles and nano technology. Sadly, a lot of nonsense has also been sold.
The term nano tells us, in particular, something about the size of the particles. Nano particles are particles which are smaller than 100 nanometre. (A nanometre is a billionth of a metre, so a thousandth of a millimetre). It is definitely an advantage in the sun protection field to be able to cut material into such tiny particles. These remain on the skin more readily, they are transparent instead of being white and are able to protect more effectively against sun damage.
But how safe are they? It is very important to understand that nano particles are not all the same.
The functioning and the safety of nano particles are connected to characteristics such as ability to clump together, the reaction in sunlight such as generating free radicals, the nature of the material, the exact size, form and the weight, the effect on the cell and the body’s capacity to break it down. All of these characteristics determine the eventual functioning and effect in the body. Just compare it with either a raindrop or a small stone on your windscreen; the same size, but having a very different effect. Without going into too much detail about all the various nano materials, we know from research into tinosorb M that these particles are relatively large, that the particles clump together and that the molecular weight of them is high (for those who would like to know precisely: above 500 dalton). Therefore, tinosorb M does not actually absorb through the skin. The chemical is very stable and does not form any damaging free radicals under the influence of sunlight. And that is very different to titanium dioxide and (uncoated) zinc oxide in nano form. Tinosorb M is not very likely to cause an allergy or skin irritation. And in contrast to many chemical sun filters, it doesn’t affect hormonal balance. Very recent research has revealed that tinosorb M has no effect on the DNA of the cell, and is not actually toxic. So even if the ingredient did absorb through the skin and get into the bloodstream there is no reason to panic. However, the adverse effects as described above are related to filters such as nano-titanium oxide and chemical filters such as oxybenzone and homosalate.
All of this is reason for me to add tinosorb M to my sun cream. It is one of the very few filters which I trust completely to put on my own skin and that of my children.
Inci: Tris Biphenyl Triazine (nano)
- Definition:There is less known about this form of tinosorb, however we do know that, just like tinosorb S, this sun filter has anti-inflammatory properties. In terms of size, it is most like tinosorb M. In combination with other filters, it can provide a real boost to the UVA protection.
Uvinul A Plus
Inci: Diethylamino Hydroxybenzoyl Hexyl Benzoate
- Definition:A UVA filter. There is less available research about this substance than that of tinosorb S and M. Even so, uvinul A plus appears to be the same; it is a very stable filter, does not absorb through and is not likely to cause irritation. There is no available data about possible hormone disruption and free radical forming.
Inci: Ethylhexyl Triazone
- Definition:Super, safe UVB filter. Stable, does not absorb through, not hormone disruptive and not likely to cause irritation. Iscotrizinol (Diethylhexyl Butamido Triazone) would, by the way, be an improved version of octyltriazone (Ethylhexyl Triazone), however when formulating it seems to be less photostable. Definitely comes under the good filters.
Inci: Ethylhexyl Salicylate
- Definition:Not the most stable as a ‘stand-alone’ filter. But this is never actually used on its own because it is a UVB filter. It is stable when combined with other filters. Octisalate does not absorb into the body, is not hormone disruptive, is not likely to cause irritation and does not cause free radicals to form.
Inci: Phenylbenzimidazol Sulfonic Acid
- Definition:This filter is stable, even has an anti-inflammatory action and low risk of skin allergy/irritation. There is free radical forming however (a problem with many filters, including the non-chemical filters zinc oxide and titanium dioxide). It is, at the same time, also described as being able to eliminate free radicals under UVB rays.
Inci name: Terephthalylidene Dicamphor Sulfonic Acid
- Definition:A super, broad spectrum filter which particularly stands out in your UVA protection. The substance does not or hardly absorbs into the body (max 0.1% of the applied dose), is stable and is not very likely to cause a skin reaction. No further data about possible hormone disruption.
Inci: Drometrizole Trisiloxane
- Definition:Interesting fact: This is the first photo stable UVA + UVB filter on the market. It is a super, broad spectrum filter, stable and hardly likely to cause a skin reaction.
Filters that, for instance, are more likely to cause an allergic reaction and are also instable and/or form free radicals. Or filters where (too) little information is provided.
Avobenzone (Parsol 1789)
Inci: Butyl Methoxydibenzoylmethane
- Definition:I have a love-hate relationship with avobenzone. What is good about this filter: it is a very good UVA protector. On the other hand, however, avobenzone is very instable and is quite likely to cause an allergic skin reaction. In terms of instability, avobenzone can be corrected with other filters– they make sure that the filter can do its work and does not degrade in the sun. It is usually octocrylene (see red list), though, which is used to stabilise this…
Should you not respond well to a product and you see that this combination has been used in your sun cream, then the likelihood is that these are the culprits. Furthermore, avobenzone should not be used in combination with octinoxate (ethylhexyl methoxycinnamate); this filter actually causes avobenzone to degrade more rapidly.
Inci: Disodium Phenyl Dibenzimidazole Tetrasulfonate
- Definition:A stable filter which does not/or hardly absorbs through the skin, but where little is actually known about free radical forming and possible hormone disrupting properties. As well as this, there is a risk of skin reaction. A questionable option thus.
Inci: Dimethicone Diethyl Benzylmalonate
- Definition:A stable filter with very few reports about allergic reactions. It is a UVB filter but, in terms of ability to absorb UV light, it is not great in comparison to other filters. And very little further research into this has been done. Unlike many other filters, this chemical leaves a nice feel on the skin.
Zinc oxide and titanium dioxide (nano)
Filters which are known to absorb easily into the body and can disrupt hormones.
- Definition:It is a complete puzzle to me as to why this filter can still be used in the U.S.A., where, for example, tinosorb has still not been endorsed. No filter has had so much evidence against it as oxybenzone. The chemical is hormone disruptive, causes free radicals to form, is easily absorbed by the body (even through healthy skin), highly likely to cause skin irritation, is instable and, on top of that, this sun filter is extremely environmentally ‘unfriendly’.
- Definition:This filter also has hormone disruptive properties and, just as its partner above, absorbs easily into the body. Sulisobenzone is also highly likely to cause skin irritation and the chemical potentially causes free radicals to form.
Inci: 4-Methylbenzylidene Camphor
- Definition:I have to say that I don’t often see this filter in the ingredients list of sun creams which I receive daily from blog readers. But if I do come across the chemical then I will dissuade its use. In laboratory tests the filter appears to be hormone disruptive, is easily absorbed by the body, is highly likely to cause skin irritation and also forms free radicals.
Inci: Homomenthyl Salicylate
- Definition:Homosalate is very stable, but research has suggested that this filter can possibly be absorbed by the body and is also hormone disruptive. Alongside this, there is also even a high likelihood of a (allergic) skin reaction. These are enough reasons for me to avoid it.
Inci: Ethylhexyl Methoxycinnamate of Octyl Methoxycinnamate
- Definition:This, funnily enough, is one of the most commonly used sun filters worldwide, however, I am placing it in the list ‘best avoid’. Ethylhexyl methoxycinnamate is very easily absorbed by the body and acts like oestrogen. Furthermore, according to research, free radicals form when exposed to the sun and the filter is harmful to the environment. Alongide this, ethylhexyl methoxycinnamate can become inactive under the influence of light. All in all, not very pleasant properties. On the other hand, octinoxate is unlikely to cause skin irritation.
- Definition:This filter has always been a debatable one for me. I always eventually ‘approved’ sun creams with this chemical. But with new insight I have actually moved this filter into the red row. Octocrylene is potentially free radical forming and many skin reactions are reported, particularly in children. This filter also appears to have a hormone disruptive action in experiments on animals. Additionally, the chemical penetrates easily through the skin.
Inci: Octyldimethyl PABA / Ethylhexyl Dimethyl PABA
- Definition:This is a derivative of the perhaps well-known PABA (Para-Aminobenzoic Acid). PABA was one of the very first sun filters. Nowadays, the chemical is no longer being used because it was discovered fairly quickly that it caused allergic reactions, the formation of free radicals and deep penetration. The filter even proved to be potentially carcinogenic in laboratory tests. Having said that, PABA is still allowed to be used. If you discover this abbreviation in the ingredients list then you are best off putting the product back on the shelf. Derivatives such as octyldimethyl PABA do form a safer option, but remain controversial.
Inci: Isoamyl p-Methoxycinnamate
- Definition:There is still very little known about this filter. As you can see by the name it is related to octinoxate (which is very often used in sun creams). There are a great deal of publications about skin reactions to this filter.
A few more comments
So, here is another small remark that I sometimes make about the possibility of sun filters absorbing into the body via the skin. That possibility is, of course, smaller in a healthy, strong skin than, for instance, the delicate skin of children or of people with skin conditions such as eczema or rosacea. In terms of hormone disrupting properties: sun filters are often (on their own) tested for this in laboratories; it is not clear what the actual effect is on the body. But considering the frequency and amount you apply onto your children and yourself, I would much rather choose a product with filters from the green list.
I do understand, by the way, that after reading this list, with difficult and unpronounceable chemical names and properties, you may be feeling slightly dizzy. So I have also put together for you a refined list with sun creams which I have already screened. And once again: it is always better to apply a lower quality product than nothing at all!
Research Physician Cosmetic Dermatology
P.S. If there is a filter not on the list, which you would like information about, then do get in touch.