Vetrice albastră

Botany and origin

Blue tansy, also called Moroccan blue chamomile, is an herbaceous plant that grows wild in the countries of the Mediterranean Basin. Overcultivation in Morocco has complicated its supply and resulted in unreliable quality.

Composition

More than 130 constituents have been identified in the oil from Moroccan Tanacetum annuum. Its major components are chamazulene (38-17%), myrcene (14-1%), sabinene (8.6-4%), beta-eudesmol (7-3%) and camphor (18-4%). Seasonal variation of the oil composition suggested that the chamazulene content decreases and the myrcene content increases from June to October.

Common tansy and blue chamomile

Blue tansy is often confused with common tansy, Tanacetum vulgare, but its oil contains no thujone and high amounts of chamazulene, which makes it dark blue. The leaves and flowers of common tansy are toxic if consumed in large quantities, and its volatile oil contains thujone. The oil of common tansy is never blue, as it contains no chamazulene. Some resellers adulterate the very expensive blue tansy oil with the much cheaper oil from Tanacetum vulgare. German chamomile, Matricaria chamomilla, is also called blue chamomile, because the blue colour of its oil is attributable to chamazulene.