Citronellol is a terpene with a fresh, floral-citrus aroma that can be found in rose and other botanical oils. Citronellol is well known as an effective mosquito repellent and has long been used in perfume and beauty products. Research into its medical uses is growing, and it shows potential as a useful anti-inflammatory, anti-tumor, and cardiovascular regulating agent.
What is citronellol?
Also referred to as dihydrogeraniol, citronellol occurs naturally in citronella oil, an essential oil derived from the leaves and stems of the lemongrass plant. Citronella oil's two main chemotypes, Ceylon and Java, are so named because of the oil's probable origin in Sri Lanka. Citronella oil is produced primarily in Asia, with up to 40% of the world's supply coming from China and Indonesia. Madagascar, Honduras, and Mexico are among the world's other producers of citronella oil.
Citronellol in everyday life
The most common way we encounter the citronellol terpene in our everyday lives is when we use mosquito repellent on a hot summer day. Citronellol may be included in repellents in candles, sprays, and diffusers. The naturally occurring terpene, classified by the EPA as a minimum risk pesticide, may be preferred to formulas that contain DEET and other chemicals.
In addition to its utility in mosquito repellents, citronellol's balance of floral and citrus notes make it a popular scent-enhancing ingredient in perfume and skin-care products such as body oil, after-shave balm, and deodorant soap. If you've ever purchased a skin-care product labeled as “citrus-scented” there's a good chance that citronellol was an ingredient. You may also have gotten a whiff of citronellol if you've ever burned incense made with citronella oil. There is, however, some controversy about whether citronellol in cosmetics could be a skin allergen, and European companies are required to declare on product labels if the terpene is an ingredient.
Therapeutic benefits of citronellol
Aside from its widespread usage in mosquito repellents, citronellol may also have tumor-inhibiting and anti-inflammatory effects, each of which warrants further scientific study.
Inflammation is often an important component of pain, and animal studies have shown that citronellol may reduce pain by several different anti-inflammatory mechanisms. The human body has many different inflammatory responses and pathways, and laboratory studies in cultured cells have shown that citronellol may fight inflammation by several different mechanisms.
Citronellol's anti-inflammatory action may also support its potential to fight tumors, as inflammation contributes to the formation of cancerous cells. Some studies have shown that citronellol could be a viable lung cancer treatment because it is so volatile and it could be absorbed by the lungs using an inhaler. Additional studies on humans would clarify whether citronellol or its accompanying components such as geraniol can definitively play a role in combating cancerous tumors.
Citronellol appears to have pronounced inhibitory effects on the cardiovascular system, by inhibiting the contraction of smooth muscle cells. This effect could potentially be leveraged to dilate blood vessels and lower blood pressure, although clinical trials in humans are needed.
Role of citronellol in cannabis
Citronellol may be present in geraniol varieties of cannabis, such as Great White Shark, Island Sweet Skunk, and Amnesia Haze. The scent and flavor properties associated with citronellol in cannabis have a lemony citrus base, as lemongrass is the plant origin. The aroma and flavor of cannabis containing citronellol may alternately be perceived as similar to geraniums, passionfruit, or honey.
Deceptively sweet and flowery, citronellol may act as a killer to mosquitoes and possibly tumors.
Major contributions from Dr. Adie Rae.