One of the warnings you’ll see with some essential oils is not to use them if you will be exposed to sunlight (or any UV light). For this reason we need to be careful when adding essential oils to sun cream, or lotion that you will wear in the sun.
This article, on WestCoastAromatherapy.com provides an overview of phototoxicity, and lists which oils fall into the category of phototoxic. As with all oils, you should carry out a skin test before using a new oil – particularly if you will be exposed to UC rays.
Have you seen the precaution – If applied to the skin avoid sunlight or UV rays (including sun beds) for 12 hours or something similar on some essential oils or essential oil blends and wondered what this was all about?
Phototoxicity is a reaction that can occurs on the skin when it is exposed to sunlight (or UV rays) in the presence of certain chemicals. The most common phototoxic agents are psoralens, or furocoumarins. These polycyclic molecules have a structure that gives them the ability to absorb ultra violet photons, store them for a while and then release them in a burst on to the skin.
The reaction will only occur if the sensitizing agent is present on the skin when it is exposed to Ultra Violet light and can take the form of a mild color change all the way through to deep weeping burns. Sometimes the skin is able to revert back to normal over time, but at other times the reaction can be permanent. The reaction can occur almost immediately, or it can be delayed and only occur following a period of sensitization.
Only a few essential oils contain these phototoxic components and while it is usually in amounts of less than 2%, even at this low level and even when the oil is diluted down with a carrier to a 1 – 3% dilution, they are still often capable of producing phototoxic effects if the skin is then exposed to sunlight or UV rays. If these essential oils were to be used undiluted or if the skin were to be exposed to concentrated UV light or strong sunlight then a very severe phototoxic effect could occur.
Read on for some of the more phototoxic essential oils…