I LOVE essential oils. I've amassed a nice collection over the years because of my frequent perusal of the essential oils section at my local health food store. All those beautiful smells with their healthful benefits — I can't get enough. So I picked up a fancy, flowery blended oil the other day and I was happily diffusing it in my home when I started getting a big ol' headache out of nowhere. It didn't dawn on me right away that it could be my new oil because I've never had that reaction before. When I did finally realize it could be the problem, I turned it off and felt better in an hour. What the heck?
It's unusual for me to skip the full check of ingredients before buying something new, but even I get lax every now and again. I guess this was one of those times because I failed to notice one word on that new bottle: absolute.
Turns out that blend of oils contained one absolute oil among the essential oils, and I'm sure that's what I was reacting to.
What's the Difference Between Essential Oils and Absolute Oils?
Essential oils are primarily produced through the process of steam distillation, but some flowers (lily, lotus, jasmine, tuberose, carnation, gardenia, jonquil, violet leaf, narcissus and mimosa) are too delicate for steam (heat) distillation and are extracted using solvents instead.
An absolute oil is an essence, having an extremely high concentration of fragrance very close to the natural smell of the plant material. Because of their high concentration of aromatics, absolutes are most often used in perfumery instead of aromatherapy or other health-related applications. Absolutes are often blended with essential oils, CO2 extracts and other types of extracted aromatics in alcohol or in a fixed oil (like Jojoba).
According to NAHA.org,
Solvent extraction is the use of solvents, such as petroleum ether, methanol, ethanol, or hexane, to extract the odoriferous lipophilic material from the plant. The solvent will also pull out the chlorophyll and other plant tissue, resulting in a highly colored or thick/viscous extract. The first product made via solvent extraction is known as a concrete. A concrete is the concentrated extract that contains the waxes and/or fats as well as the odoriferous material from the plant. The concrete is then mixed with alcohol, which serves to extract the aromatic principle of the material. The final product is known as an absolute.
What About Solvent Residue?
Solvent residue (the chemicals remaining in the final product after solvent extraction methods are used) is a real concern. There are varying reports as to how much is actually left in a finished absolute oil, ranging from 5 parts per million all the way up to 20% of the final product. The higher residue amounts seem to be referring to absolutes made with benzene which is a dangerous Class 1 solvent that's no longer used for any essential oil extractions.
US Pharmacopeia standards set the following limits on residual amounts of common chemicals used in the solvent extraction process:
- Hexane (Class 2) – 290 ppm
- Methanol (Class 2) – 3000 ppm
- Ethanol (Class 3) – 5000 ppm
The current European Union standards require less than 10 ppm solvent residues in a finished absolute. However, even with such a small residue (less than .0001%), many aromatherapists and oils experts won't use absolutes because of the potential negative effects of the residual chemicals.
And that's our recommendation too. At this point, there are much safer and widely available options in steam distilled essential oils.
P.S. Click here to learn more about how synthetic fragrances can also cause headaches and other health issues just like the solvents in absolute oils can.