Blue tansy oil is an essential oil steam-distilled from the flowers and leaves of Tanacetum annuum, a plant native to Morocco and the Mediterranean region. Its striking deep blue color comes from a compound called chamazulene, which doesn’t actually exist in the fresh plant but is created during the distillation process itself. The oil has gained popularity in skincare for its soothing, anti-inflammatory properties.
Why the Oil Is Blue
The vivid blue color is the defining feature of this oil, and the chemistry behind it is unusual. The fresh flowers of Tanacetum annuum contain a precursor compound that transforms into chamazulene when exposed to the heat and steam of distillation. This means a CO2 extract or cold-pressed version of the same plant would come out green or yellow. Only the steam-distilled oil turns blue.
German chamomile undergoes the same chemical transformation, which is why both oils share that distinctive ink-blue hue. In German chamomile, oils with less than 3% chamazulene tend to look green or yellow, while those with more than 7% are reliably dark blue. Blue tansy oil typically contains 13 to 16% chamazulene, which accounts for its intense, consistent color.
Chemical Profile and Key Compounds
Chamazulene gets the most attention, but it’s only one piece of the oil’s chemistry. Analysis of blue tansy samples shows the oil contains a complex mix of compounds, with notable variation between batches. One tested sample broke down to sabinene (15.8%), chamazulene (15.6%), and camphor (10.6%) as the top three constituents. A second sample from a different source showed chamazulene at 13.5% alongside camphene (15.8%) and a compound called alpha-bisabolol oxide A at 29%.
This variability matters. Sabinene and camphor contribute to the oil’s herbaceous, slightly sharp aroma. Chamazulene is responsible for the anti-inflammatory reputation. The ratio between these compounds shifts depending on growing conditions, harvest timing, and distillation methods, so two bottles of blue tansy oil from different suppliers can smell and perform quite differently.
Not the Same as Common Tansy
Blue tansy (Tanacetum annuum) is frequently confused with common tansy (Tanacetum vulgare), a different species with a very different safety profile. Common tansy contains high levels of thujone, a compound that is toxic in concentrated form. Blue tansy does not contain significant thujone. This distinction is critical when purchasing the oil. Always check that the Latin name on the bottle reads Tanacetum annuum, not Tanacetum vulgare.
Skincare Uses
Blue tansy oil shows up most often in facial oils and serums marketed for reactive, acne-prone, or easily irritated skin. Chamazulene has documented anti-inflammatory activity, which is why the oil is used to calm redness, reduce the appearance of irritation, and soothe skin after sun exposure or environmental stress. Camphor, another major constituent, contributes mild cooling and analgesic effects on the skin.
In aromatherapy, the oil is used for relaxation and stress relief. Its scent is sweet and herbaceous with a slightly fruity quality, distinct from the sharper medicinal smell that many people associate with other blue-colored essential oils like eucalyptus.
How to Use It Safely
Like all essential oils, blue tansy should be diluted in a carrier oil before applying to skin. For facial use, a 1 to 2% dilution is standard, which works out to roughly 3 to 6 drops of essential oil per tablespoon of carrier oil. For body application, you can go up to 3 or 4%. Jojoba oil and light mineral oil are common carriers that pair well with it.
Before applying it to your full face, test a small amount of the diluted oil on the inside of your wrist or behind your ear and wait 24 hours to check for a reaction. The oil’s deep blue color will tint your carrier oil and can temporarily leave a faint blue cast on skin or stain light-colored fabrics.
Why It’s Expensive
Blue tansy oil is one of the pricier essential oils on the market, and there’s a straightforward reason. Tanacetum annuum grows in a limited geographic range, primarily Morocco, and the yield per harvest is relatively low. Steam distillation of the plant material produces small quantities of oil compared to more commonly cultivated species like lavender or tea tree. This limited supply, combined with growing demand from the natural skincare industry, keeps prices high and makes adulteration a real concern. Reputable suppliers will provide GC-MS testing results (a chemical analysis of the oil’s composition) to verify authenticity. If a blue tansy oil seems unusually cheap, it may be diluted or blended with other blue-tinted oils.