Cannabis flower essential oil

Cannabis flower essential oil, also known as cannabis essential oil, is an essential oil obtained by steam distillation from the flowers, panicles (flower clusters), stem and upper leaves of the hemp plant (Cannabis sativa L.) (Kaniewski R et al. (2005). It consists of a mixture of monoterpenes (92%), sesquiterpenes (7%) and about 1% other compounds (ketones, esters). The dominant monoterpenes were myrcene (67%) and limonene (16%). The most abundant monoterpene was β-myrcene, followed by trans-caryophyllene, α-pinene, trans-ocimene and α-terpinols. The major alkane in an essential oil obtained by extraction and steam distillation was the n-C29 alkane nonacosane (55.8 and 10.7%, respectively). The concentrations of the constituents depend on the growing region and the plant variety.

The essential oil is produced from hemp varieties with low THC content ("fiber type") as well as with high THC content ("drug type"). Since most phytocannabinoids are nearly insoluble in water, hemp essential oil contains only trace amounts of cannabinoids. Even in "drug hemp", the THC content of the essential oil does not exceed 0.08% (Mediavilla Vito et al. 1997). Yield depends on hemp variety (drug, fibre) and pollination, sex, age and part of the plant, cultivation (indoor, outdoor, etc.), harvest time and conditions, drying and storage. For example, fresh buds of an Afghan variety yielded 0.29% essential oil. Drying and storage reduced the content from 0.29% to 0.20% after 1 week and to 0.13% after 3 months.

The various terpenes in cannabis have antifungal, antimicrobial, antiviral, and insect repellent functions that could be commercially valuable when applied topically.

Hemp essential oil is used as a fragrance in perfumes, cosmetics, soaps and candles. It is also used as a flavouring in food, especially in sweets and drinks. As an additive to massage and skin oils, hemp essential oil is said to have a calming and anti-inflammatory effect and relieve tension.

Hemp essential oil is to be distinguished from hemp seed oil (pressed edible oil from plant seeds) and THC-containing hash oil. Hash oil is a THC-rich extract from dried female hemp flowers (marijuana) or resin (hashish).

1. Kaniewski R et al (2005). Steam Distillation of Essential Oils from Hemp Panicles. Journal of Natural Fibers 1: 91-92.
2. Mediavilla Vito et al. (1997) Essential oil of Cannabis sativa L. strains. Journal of the International Hemp Association. 4: 80–82
3. Vuerich M et al. (2019) Yield and Quality of Essential Oils in Hemp Varieties in Different Environments. Agronomy 9: 356.