Hello All,
Like most people, I have some beliefs that are not always supported by science. Recently I was challenged by one of the members of the forum for my take on alcohol in skincare, which made me start double checking my views. One of my beliefs is that essential oils are bad for the skin. They are irritants and some are even phototoxic. My google search didn't give me much though. I found a couple of articles on Forbes and New York Times, and I don't think those are legit sources for the skincare science. I would appreciate the views (and maybe links to serious researches) of the experienced members of the forum.
Thank you all in advance!
Comments
Essential oils are are very complicated raw material, they are constituted of thousands of molecules, and change their composition between different species, and for the same species but from year to year. So as far as I know there is no general study on essential oils. But you can take the essential oils that interest you, research their chemical composition, take the names of the molecules you find, and look for each molecule, this is the best way to find toxicological info about essential oils.
So, your point is that we can't look at them as a group the same way we look at silicones and parabens?
You can find a lot of scientific literature on the Limonene for example (a major component of the citrus oils), or a-pinene (a major component of pine oil). But always keep in mind that the information is highly limited.
1) Price
2) Price
3) Stability
And yes, some could be irritant. And that's why perfumists take home big fat checks, for formulating a sub that will be affordable, much more stable and with less allergens.
However, it's not fair to look at silicones as a group. The wide variety of molecules and functions of those molecules makes the term "silicones" no less broad than the category "hydrocarbons."
For your question, here is a recent review of the biological effects of essential oils published in a peer reviewed journal on toxicology.
https://www.dropbox.com/s/hqg5nqs4vbqvf63/essential-oil-review.pdf?dl=0
Of note..."Depending on type and concentration, they exhibit cytotoxic effects on living cells..."
Of course, this effect can be good if it is attacking parasites and problematic microbes, it can be bad if it is attacking human cells.
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Big companies hire fragrances houses like IFF, Givaudan, or Firmenich to make their fragrances.
When working within safe levels of essential oils, as determined on a case-by-case basis, and remembering that essential oils can function as a dermal penetration enhancer, I personally like following the "As much as needed, as little as possible" approach.
The reason you won't see statements on the composition (expect well-known allergens or which they should state) of perfumes is that they are considered trade secrets (from a regulatory standpoint and therefore does not need to be divulged) in both the US and EU - I presume elsewhere too, but don't know for certain.
I do however agree that when buying a predefined perfume "the scent of an orange" can be frustrating because, like with colours, organoleptic properties is perceived differently.
2 books I find interesting on the subject of perfume and essential oils are:
Perfume: The biology and Psychology of fragrance
https://www.springer.com/us/book/9789400912151
It's a tad old, but I find it interesting and knowledge never gets old, only superseded.
Handbook of Essential Oils: Science, Technology, and Applications
https://www.crcpress.com/Handbook-of-Essential-Oils-Science-Technology-and-Applications-Second/Baser-Buchbauer/p/book/9781466590465
I used to think that way. More recently I have discovered that using EOs instead of fragrance ruins the products. EG, I made some body shampoo a few days ago and it was completely destabilised (ruined) by the addition of 0.5% lavender EO.
Still the most dangerous thing about EOs are bees. I've heard scary and funny stories about labs overrun and people hiding in the bathroom because of it.
Cofounder & Chief Formulator
Indochine Natural
Cofounder & Chief Formulator
Indochine Natural
However, the first thing a consumer will usually do when they open a container of a new skin care product is smell it. Fragrance is simply an important component of the consumer experience, for most.
You can try hydrosols or essential oils, but I've found that hydrosols, with the exception of Rose, are too weak to impart an acceptable fragrance and they smell "hay-like". Carrubba has a line of natural, water-soluble fragrances that I find to be a good option in lieu of essential oils. But, if you choose your essential oils properly (there are non-sensitizing EO's on the market), you can generally create a nice fragrance profile w/o irritation or allergic reactions.
See website for details www.desertinbloomcosmeticslab.com
as @perry said when he linked the article:
Of note..."Depending on type and concentration, they exhibit cytotoxic effects on living cells..."
Think of it this way (overly simplified) Hazard x Exposure = Risk.
If you take 1 drop of essential oil directly onto the skin, you are likely to experience irritant contact dermatitis (in part due to cytotoxicity) but if that same drop is diluted in a cup of oil, that drop is perfectly safe to use because the exposure is much less.