How to safely use photosensitive essential oils in summer
Identifying Phototoxic Essential Oils
Cold-pressed citrus oils are among the most commonly recognized phototoxic essential oils. However, not all citrus oils exhibit phototoxicity. Citrus oils obtained via steam distillation rather than cold pressing typically do not contain furanocoumarins, the primary compounds responsible for phototoxic reactions.
Certain citrus oils, such as bergamot, are available in furanocoumarin-free (FCF) formulations, where compounds like bergapten are significantly reduced or removed through the distillation process. The extraction method and plant part used play a critical role in determining the phototoxic potential of an essential oil. While specific photoreactive compounds may be present in the raw plant material, they may not necessarily be carried over into the final essential oil, particularly if produced via steam distillation.
In general, when citrus oils are cold-pressed or expressed, phototoxic constituents are more likely to be retained during extraction, thereby increasing the risk of photosensitization upon topical application and subsequent UV exposure.
How to Identify a Phototoxic Reaction
A phototoxic reaction may occur within 24 to 72 hours after the application of an essential oil followed by exposure to ultraviolet (UV) radiation. The most common clinical manifestations include severe sunburn-like erythema and blistering.
If a phototoxic reaction is suspected, consider the following contributing factors:
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Dilution:
The risk of phototoxicity is influenced by the concentration of phototoxic essential oils in a formulation. When these oils constitute a significant proportion of a topical product, especially if used undiluted or inadequately diluted, the likelihood of a reaction increases upon exposure to sunlight or UV radiation. -
Dosage:
This refers to the amount of oil or product applied to the skin prior to UV exposure. Higher doses of phototoxic oils or products containing them can result in more severe reactions. -
UV Exposure Duration:
The length and intensity of sun exposure are critical in determining the onset and severity of a phototoxic response. Prolonged outdoor activities—such as walking, playing, or working under direct sunlight—significantly increase the risk. In contrast, brief exposure (e.g., walking from one location to another) is generally insufficient to trigger a reaction.
How to Safely Use Phototoxic Essential Oils
You don’t need to give up your favorite essential oils during the summer months! With the right knowledge and mindful usage, you can still enjoy the benefits of certain oils without causing any harm to your skin. Below are safe and effective ways to use cold-pressed phototoxic essential oils throughout the year:
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Consider Inhalation as a Safe Application Method
Inhalation of essential oils containing phototoxic compounds does not pose any risk of phototoxic reaction. Therefore, using these oils in aromatherapy practices—such as through diffusers, aroma sticks, or aromatic jewelry—is completely safe, even if you plan to go outdoors afterward. -
Use Phototoxic Oils in Rinse-Off Products
Phototoxic essential oils can be safely applied to the skin as long as they are formulated in rinse-off products. Soaps, body washes, and shampoos provide excellent vehicles for incorporating citrus oils, which may not be suitable for prolonged leave-on topical use. This allows you to enjoy their fresh, vibrant aromas without the risk of phototoxic irritation. -
Choose Non-Phototoxic Alternatives to Your Favorite Oils
Some essential oils, such as bergamot FCF (furanocoumarin-free), are specially formulated to exclude compounds like bergapten and can be used safely on sun-exposed skin. Likewise, steam-distilled versions of oils like lemon and lime are safer substitutes for their cold-pressed counterparts. -
Protect and Cover Treated Skin
If phototoxic essential oils have been applied topically, ensure the area is adequately covered with clothing, hats, or sun-protective measures. Avoid direct sun exposure for at least 24 hours after application to minimize the risk of a reaction. -
Dilute to Safe Concentrations to Minimize Phototoxic Risk
Proper dilution in a carrier oil significantly reduces the phototoxic potential of essential oils. However, when blending multiple phototoxic oils, the cumulative concentration must still be considered, as the overall phototoxicity may exceed safe limits even after dilution.
