If you’re new to essential oils, then you may not know that some essential oils can make your skin very sensitive to sunlight exposure. This is known as phototoxicity or photosensitization.
All About Phototoxic Essential Oils
Phototoxicity is a skin reaction that occurs when certain constituents in an essential oil react with ultra violet light. These constituents are capable of absorbing energy from the sun’s rays much more effectively than our skin. Essential oils that are known to have this ability are listed as phototoxic or photosensitizers and are only hazardous to the skin when they are applied and exposed to direct sunlight or other forms of ultra violet light.
Citrus oils in particular that are extracted by direct expression (meaning cold pressed extraction) without distillation are generally considered phototoxic essential oils. This is due to their high amounts of a chemical known as furocoumarins. The higher the furocoumarins the more phototoxic the essential oil. Other oils that have a similar phototoxic effect because they contain psoralens are lemon verbena, angelica root, rue, fig leaf absolute, and tagetes essential oil. Both of these chemicals have the ability to absorb ultra violet photons, store them, and then release them onto the skin.
The Signs of Phototoxicity
Phototoxicity will only occur if the essential oil is present on the skin when it is directly exposed to ultra violet light such as sunlight, tanning beds, etc. The skin may begin to change color and darken leaving behind hyperpigmentation. Phototoxic essential oils can even cause severe weeping burns, blistering, and edema. The reaction can occur right away or take several hours to appear.
Bergamot essential oil is considered to be one of the most phototoxic essential oils and produces an abnormally dark pigmentation on the skin when exposed to sunlight. This is called berloque dermatitis or bergapten dermatitis that can last for many years. This is why it is super important to take special precautions when using phototoxic essential oils.
Degrees of Phototoxicity in Essential Oils
Some essential oils are more phototoxic than others and it’s good to know to what degree an essential oil causes photosensitivity.
Just remember that:
If you use steam distilled citrus essential oils they will not be phototoxic because the chemicals that make them so are too heavy to be present in the final product.
Cold pressed is when the peels of the citrus are being punctured and pressed and all of the constituents present in the essential oil will be present in the final product including phototoxic chemicals.
Phototoxic Essential Oils
• Angelica root
• Cold-pressed bitter orange
• Cold-pressed lime
• Fig leaf absolute
• German Chamomile
• Kaffir lime
• Lemon verbena
• Opopanax (sweet myrrh)
• Tagetes (marigold- not to be confused with calendula)
Mildly Phototoxic Essential Oils
• Cinnamon bark
• Cold-pressed grapefruit
• Cold-pressed lemon
• Cold-pressed sweet orange (contains very low amounts of furocoumarins and is widely considered safe to use)
• Cold-pressed tangerine
Mandarin essential oil has trace amounts of furocoumarins and is considered very mildly phototoxic.
Non-phototoxic Essential Oils (within the citrus family)
Here are a few essential oils that MAY be phototoxic and should be used with caution:
• Bay laurel
• Black pepper
• Cinnamon leaf
• Clove bud
• Spanish sage
• Star anise
• Sweet fennel
• West indian bay
• White thyme
On an interesting side note, one of the most mind boggling essential oils is Myrrh (Commiphora myrrha). Despite the fact that it contains 10 different types of furocoumarins that make up 20-27% of its chemical makeup (more than any other essential oil), it is not phototoxic. It is believed that myrrh’s sesquiterpenes mitigate and effectively “quench” the solar amplifying properties of the furocoumarins. So in fact, myrrh has a sun protection like effect instead of phototoxicity.
Recommended Precautions When Using Phototoxic Essential Oils Topically
If you do happen to use phototoxic essential oils topically on areas of the skin that may be exposed to sunlight (like during your nightly skincare routine), then the guidelines below will help keep your skin safe.
Avoid Sun Exposure for 12 Hours After Application
• Cold pressed tangerine
Avoid Sun Exposure for 24 Hours After Application
Avoid Sun Exposure for 48 Hours After Application
Avoid Sun Exposure for 72 Hours After Application
• Cold pressed lime
Remember that if you apply the oils under clothing you do not have to worry about this! This is only if you apply these oils on areas that will receive direct sunlight.
How to Safely Use Phototoxic Essential Oils in The Sun
When heavily diluted, you can use phototoxic essential oils in the sun without getting sunburned.
Here’s how many drops you can safely use per ounce of carrier oil:
• Angelica root– 3 drops
• Bergamot– 1 drop
• Bitter orange– 8 drops
• Cold-pressed lemon– 12 drops
• Cold-pressed lime– 4 drops
• Grapefruit– 24 drops
• Opopanax aka sweet myrrh– unknown
Using phototoxic essential oils in products like soap, body wash, and shampoos are generally safe because they are being washed away. However, if you are using them in recipes for body lotion, lip balm, hand cream, and other products that stay on the skin then you will need to follow the dilution guidelines above.
If you make your own “wash off the skin” body care products, you can check out the list below for dilution guidelines.
• Bergamot– 30 drops per ounce of carrier
• Bitter orange– 30 drops per ounce of carrier
• Grapefruit– 30 drops per ounce of carrier
• Lemon– 30 drops per ounce of carrier
• Lime– 150 drops per ounce of carrier (yep, you can use a whopping 25% dilution!)
These guidelines are for those who do not take and medications of OTC drugs that cause photosensitivity. Using these drugs while applying phototoxic essential oils will increase your chances for getting burned and is not recommended.
Just remember that as a whole, phototoxic essential oils should not be feared rather than respected. You can definitely use these oils on a daily basis without worry as long as the oils are applied on areas covered by clothing. That’s it!
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