Phenoxyethanol is a preservative that hasn’t gathered a huge amount of attention until recently. This is largely because of what it isn’t. It isn’t a formaldehyde donor. It isn’t particularly sensitising. It has never been linked with cancer. Basically it has kept its head down and nobody has taken a lot of notice of it. This has changed recently, but I will get onto that a bit later. First lets look at its good points and why it has been so widely used despite not being talked about very much.
Chemically speaking it is an aromatic alcohol related to benzyl alcohol. It has one great advantage over its cousin in that it is less prone to oxidation. Benzyl alcohol can be oxidised fairly easily which can give your formulation a fruity smell which builds up over time. It isn’t unpleasant but it isn’t what you want. It is very much the point of a brand that it is the same every time you buy it. You don’t really want to have lay down your anti-ageing cream in a cellar to mature like you would a fine wine.
It is also relatively non-toxic, particularly for a preservative, so it is a pretty safe choice. It actually gets used as a preservative in intravenous drips to give you some idea of just how low risk it is.
But this lack of toxicity is not a total blessing in a preservative. You do have to use relatively high levels which can affect other aspects of the formulation, particularly solubility of other ingredients. And although it doesn’t cause many sensitisation reactions, they do occur and the high use level is a factor in this. One way round this is to use it in combination with another preservative. Phenoxyethanol is weak against fungi, so the fairly strongly anti-fungal potassium sorbate is a good choice. But this of course means you have another preservative which will inevitably bring its own problems.
So on balance it is a pretty good option, even if like most things it isn’t perfect. It has certainly been embraced by the natural sector. It turns up in a lot of products that make a virtue of avoiding troublesome ingredients. The Soil Association approves its use, as did until quite recently Ecocert. (I think this means that the Soil Association would no longer approve it as they are now working to the same rules – but the relationships between the certifying bodies are a bit byzantine.) It is on a rather short list of positively approved preservatives under the american NSF/ANSI 305 standard for organic cosmetic products. They even allow it from petrochemical sources. I am not sure I follow the logic, but at least it makes it possible to produce approved organic personal care products without having to risk the health of your customers.
The change of heart about phenoxyethanol comes about as a result of a French government committee issuing guidelines on the use level of phenoxyethanol in products intended for children. Most things you put on your skin have a very low chance of getting through the skin barrier, but phenoxyethanol is one of the few things that has the right kind of characteristics to penetrate the skin’s barrier. As a result of this EU regulations limit the concentration you are allowed to use to 1%. This is a sensible precaution with quite a wide safety margin. But of course children are smaller than adults, so it makes sense that if you are formulating for children then all other things being equal a lower limit would be advisable. It was basically just a bit of good advice. However it got picked up in some places and was interpreted as meaning that some new risk had been identified.
Cosmetic chemists have to keep an eye open for these things. An ingredient gets a bad name: all logic goes out the window. Reformulating to change preservatives is a boring and thankless task. But if enough fuss gets made it becomes inevitable. Luckily this one seems to have failed to strike a chord with the public so far. I dare say phenoxyethanol free claims will pop up, but it doesn’t look like it will become one of the routinely maligned molecules. And there are people out there who are sensitised by it, so there is a place for formulations that make a point of avoiding it.
I am building up quite a collection of posts on raw materials. They are all listed on my cosmetics ingredients database.
The European Union approves phenoxyethanol at levels up to 1%