In recent years a lot of people have started making their own cosmetics. There are quite a few places online where they discuss their progress, and it makes interesting reading from my perspective. Having done it for a living for several decades it is interesting seeing what people find interesting and what they find difficult.
I rarely dip in and comment. For a start the way I look at this kind of thing is very different from people who do this kind of thing. I am interested in developing commercially successful formulations not having fun. I do have a lot of fun as it happens, but that is a side effect. So I don’t really have any more to say to someone who develops cosmetics as a hobby than a trawler man would have to talk to a weekend angler. But from time to time something crops up that gives me something to think about. For example recently someone posted a picture of a batch of face mask they had made that was obviously highly contaminated with micro-organisms. The curious thing was that they had used a very effective preservative at a very high level. I wondered what had gone wrong.
Well when I looked at the formulation things began to become clear. There was nothing wrong with the choice of preservative. The problem was the inclusion of charcoal.
Charcoal is pure carbon, but carbon of a very particular form – graphite. It is characterised by the carbon atoms forming a very particular lattice structure. This has the ability to trap small molecules. You can use this property to purify things. For example I once devised a way of treating coal tar by mixing it with charcoal for a set period to remove some of the smellier components. Charcoal tablets are prescribed to people who have taken poison. It works.
So charcoal has a very definite purifying effect. In fact this was just what had happened in this mask. The charcoal had purified the mask by absorbing the preservatives. In fact it had made it so much purer that mould had started to grow on it. So in a way it was working exactly as intended.
Purification is something that seems on the face of it to be a good thing, and it has a strong emotional appeal. A lot of religions offer to purify you. There are foods and drinks that are marketed as having a purifying effect. And needless to say, there are cosmetics that make that claim as well. At its most basic, I suppose you could say that a bar of soap has a purifying effect by cleansing your hands of dirt. But there are plenty of more esoteric claims – ones that aim to purify the skin in a more abstract way.
So it isn’t surprising to see charcoal appearing in products.
The question is, does purifying the skin with charcoal actually have any benefit? It is hard to see exactly what it might do. The body uses the skin in a minor way to get rid of toxins, so there are some materials on the skin that you want to get rid of. But the skin is regularly turning over anyway, so they are on the way out already. You can get things on the skin that might be harmful. If you live in a big city for example you are probably getting at least some particulate matter from car engines on your skin. These won’t be directly affected by the charcoal but they might be the source of hydrocarbons that could conceivably have a harmful effect. What we know about the way carcinogens work doesn’t really suggest that the skin is going to be a big risk of exposure to carcinogenic chemicals, but we don’t know enough to be sure one way or the other. So maybe, just maybe, charcoal might counter this to some extent. But you’d have to have the charcoal on your skin all the time and to regularly remove it and replace it. It works like a filter, and so like a filter can get filled and will need to be replaced if it is going to do any good. A one off treatment of part of your skin is only a very small degree of protection.
So that charcoal has some kind of benefit isn’t impossible, but I find it very far fetched. And there certainly isn’t any evidence to vouch for it.
On the whole, I don’t think that charcoal is much use as a cosmetic ingredient, even if you can work out a way of preserving it.