The Tizz about Tanzy
Tizzy – A state of nervous excitement.
I am pretty sure I know which brand started the Tansy Blue craze. Colouring cosmetics with blue essential oils such as Tansy was never a thing before, then all of a sudden customers were like ‘well I want Blue Tansy as my colour’ like it was just one of those things.
There are apparently 160 species of Tanacetum. Here we talk about just two of them.
The two types of Tansy.
Tansy is a herb which has long been used to help humans make their life a little better only most of the time it was used to keep insects away rather than as a blue dye. Tansy smells like you would expect an insect repelling oil to smell, strongly herby and not all that pleasant. That’s just one reason why I was a big gob smacked when I kept being asked about this as a cosmetic colourant. Then I remembered that Instagram has no smell feature and as most brands on there are boutique, the second big factor, price, would not be such a biggie either.
Tanacetum vulgare.
Tansy has a long lasting yellow flower that can be dried or used for oil extraction. In the Middle Ages the herb was used in homes as an insecticide and repellant and rubbed into meat to keep it from getting infested, in fact Tansy’s domestic usefulness ended up earning it the name ‘artemisia domestica’ (The encyclopaedia of Herbs and Herbalism, Malcolm Stuart, 1990). The plant also has a role in the religious life and was used in a type of pancake that was eaten at Lent (I can’t remember being offered these but they do sound rather interesting, here is a recipe). You will notice if you click through to the recipe, the comments about Tansy’s essential oil chemistry. When whole herbs are used in cooking, the essential oil is obviously a part of the mix given that it makes up part of the plant. Now the amount of Tansy essential oil one would ingest in this pancake recipe is bound to be very little given the amount of leaves actually turned into juice to make this. Most plants contain very little essential oil as a percentage of their fresh weight with 1% being a pretty decent yield (if you extract it using steam distillation). I’m not sure on the specific oil yield of tansy but one would hope it isn’t much given that it can kill you. This type of tansy is known for its high beta Thujone concentration and beta Thujone is known for its ability to bring on siezures and renal failure. If you are still interested in the history of this herb there is some more information here.
So maybe that’s not the right Tansy…
Tanacetum Annum (Moroccan Tansy)
The movement of this oil into the mainstream seems to have involved a chap called Dr Kurt Schnaubelt who recommended it as a powerful anti-inflammatory and anti-histamine oil. This chap did a lot of promotional work in the USA which is possibly why this oil took off more over there than in Europe (where I’m from) where Chamomile is still the ‘go to’ blue oil.
This oil is characteristically blue (hence why it has found a use as a blue colourant) although it is fair to say that it can also come out green, it oxidises to blue thanks to a reaction the chamazulene goes through so it really does depend on how the oil has been extracted as to whether it’s oxidised straight away or not (it will eventually regardless of the distillation method). Both types of tansy are members of the Asteracea (composite) family, the same family as chamomile, and this particular iteration of tansy is sometimes known as Moroccan Chamomile (although there do seem to be a couple of plants that go under that common name which is quite confusing) which may be on account of the similarity in benefits, odour and appearance to Blue Chamomile, it just sounds a bit sexier (maybe…) .
Blue Tansy also has a long history of medicinal use as described above by Kurt. It is native to Morocco (if you hadn’t guessed by the name above) and this article by Plant Therapy shows what it is actually like in Morocco and how the plant is harvested and extracted. The writers are probably a bit naive in thinking that not many essential oil companies come to these places, the big ones generally do but there aren’t many big ones and the really big ones tend to find a way to buy up or tie up the bigger producers. The essential oil supply chain is like a funnel with most of us being the little fish rather than the one big one. In this case what I find interesting is the note on the price. As I mentioned in the beginning, Blue Tansy has become something of an internet sensation thanks to Instagram but sadly nature doesn’t cope with trends like this very well. Things take as long as they take to grow and oil yields are relatively low (around 2% for this oil) meaning that if we all want to keep using this as a blue dye then the pressure that places on the plant may well mean that it is farmed out of existence. That’s not such a sexy story I guess.
Summing Up. Is the colour worth it?
While the chemistry for this oil is different to the Vulgare type, it has some cross-overs in terms of Camphor, Borneol, p-cymene, alpha pinene and terpinen-4-ol (a key active in Tea Tree Oil). As such it’s smell is still rather herby and pungent, not horrible but not that attractive. As the chamazylene levels (blue) in this oil can range from something in the region of 17% up to 38% it can take anywhere from 0.2-1% of this oil to get the blue colour you might want. Currently the oil is selling here in Australia for over $10,000 for 1Kg so that would mean adding $20 per Kg onto your cosmetic product for a 0.2% dose (and light colour) all the way up to $100 per Kg for a 1% dose. If we compare this to Blue Chamomile we see that the Chamazulene levels can range from 2% up to 23% (Tisserand and Young, Essential Oil Safety, 2014). Organic Blue Chamomile is currently selling for around $2300 per Kg which is a lot less than the Tansy plus Chamomile contains Bisabolol which is a well known anti-inflammatory and skin soother. Even if you used three times as much of this oil, so you ended up with a similar blue colour, your overall cost | benefit analysis would be better – $13.80 per Kg for a 0.6% addition and $69 per Kg cost for a 3% addition – which you really wouldn’t do as that’s too much. On top of that while Chamomile isn’t the best smell in the world, it is less campherous and more herby/ ‘green’ than Tansy so can be blended into a pleasant aroma more easily.
To sum up, I can see why Blue Tansy has become popular as a blue colourant, it is natural, sounds exciting, and has got some market exposure from popular ‘hand crafted’ brands. However, on the down side, it is expensive, it comes from a relatively fragile eco and farming system which can easily be wrecked by our western greed and doesn’t smell at all good. There are other natural things that customers can use to make products blue including Butterfly Pea (but again, go easy on this, it won’t last forever if we all use it), Indigo (a bit more robust a supply chain thanks to its use in jeans manufacturing over the years) and even minerals like Malachite as seen here.
Finally there is another essential oil that is blue and that’s Yarrow (Achillea Millefolium). It has a chamazulene level around 26% and smells similarly herby to Tansy but not quite as pungent. It also contains more beta Caryophyllene than Tansy (approx 2.5 as opposed to around 1% in Tansy) and this is the pain relief active. However, it does contain some Thujone than the Blue Tansy (1.8% vs none) and that’s the stuff that can give you convulsions. So, if you do decide to use this, you should be able to use it safely but don’t go crazy with it.
So my final word on this is for you, all of you, to just think beyond the Insta-good gravy train and consider all aspects of an ingredient before opting for it. The last thing you want is to solve one problem only to create three more. Oh, and by the way, that’s kind of what people do pay industry trained cosmetic chemists for, we think of all these things as part of our jobs.
Amanda x