Fun Fact Friday
Did you know that some oils are photosensitizing?
Yes most of us do know this. Which ones, and why is that?
Well first let’s define photosensitization-
Photosensitization is a reaction to something that occurs from UV lighting.
I was going to define saying sunlight, but I remember an occurrence as a young adult. I have a friend who had just started taking a St John’s Wort herbal supplement. She had gone tanning which was a common thing for her to do. She didn’t understand until later why within the next couple of days after tanning she turned up looking like a tomato. As I recall, sitting was awful for her for a couple of days. She didn’t blister, but was miserable.
As for essential oils, I have seen some pretty severe damage from this reaction floating around. Personally I have only seen one occurrence also from applying prior to tanning.
Furanocoumarins are the culprit, but not all carry the risk of photosensitization. Some show no reaction at all. Bergapten is perhaps the most widely known constituent that poses a threat, however, is not the only furanocoumarin which poses a threat. While many say all citrus could cause a reaction, that simply isn’t factual.
These oils are known to cause a photosensitive reaction:
Fig leaf absolute
Mandarin leaf/aka petitgrain
Orange (bitter & expressed)
These oils have been known to be possibly phototoxic:
Angelica root absolute & CO2
Celery seed absolute
Cumin seed absolute and CO2
It is recommended if using these oils topically above max dermal recommendations for photosensitivity that you refrain from UV exposure for 12-48 hours to avoid a possible reaction. It really depends on the concentration of furanocoumarins as to the length of time you should refrain from UV exposure. When using appropriately diluted essential oils 12-18 hours should be sufficient.
As of now these are considered non-phototoxic citrus oils (assumed based on begapten content):
Lemon leaf aka petitgrain
Orange leaf aka petitgrain
Satsuma oil (expressed)
This information comes primarily from Essential Oil Safety 2nd Edition and is based upon multiple studies cited within section 5 of this book.
Many of your max dermal recommendations will be listed under that essential oil profile at www.aromaweb.com