Myrcene

Aroma and sensory profile

Myrcene does not smell like one thing. Fragrance references file it under spicy and describe it at 5 percent dilution as peppery, terpene-like, spicy, balsamic, and faintly plastic, while its flavor at 5 to 100 parts per million reads as woody, vegetative, citrus, and fruity with a tropical mango note and a slight leafy, minty edge [1]. That split between a sharp, resinous smell and a soft, fruity taste is why the same molecule is read as hoppy in beer, green in fresh herbs, and ripe in mango. The plastic note in the neat material is real and is why myrcene is rarely used alone in perfumery; it is a raw material for other fragrance chemicals as much as a scent in its own right [1].

Myrcene has no chiral center. Its structure, 7-methyl-3-methylideneocta-1,6-diene, carries no stereodescriptor [2], so there are no enantiomers to compare and no left- or right-handed forms with different odors. Any claim to the contrary describes a different compound.

Effects and research

No human trial of myrcene alone was found in the sources reviewed. The evidence is animal and in vitro.

Sedation is the best-studied effect. In a 2024 study, mice given 50 or 200 milligrams per kilogram of beta-myrcene after chemically induced insomnia showed longer sleep duration, shorter sleep latency, and a higher rate of falling asleep, with raised GABA, serotonin, and glutamate in serum and hypothalamus and less damage to hypothalamic neurons [3]. Those doses are large; scaled to a person they exceed anything reached by smelling hops or eating mango, so the result says what the molecule can do, not what a whiff of it does.

Anti-inflammatory activity has been shown in human cartilage cells. In chondrocytes stimulated with interleukin-1 beta, myrcene inhibited nitric oxide production with a half-maximal concentration of 37.3 micrograms per milliliter, reduced activation of NF-kappa-B, JNK, and p38, lowered expression of the inflammatory gene iNOS and the cartilage-degrading enzymes MMP-1 and MMP-13, and raised the protective genes TIMP-1 and TIMP-3 [4]. The authors describe this as significant anti-inflammatory and anti-catabolic activity in a cell model of osteoarthritis [4]. It is a dish, not a joint. Claims that myrcene relaxes muscles or potentiates other compounds in people rest on no controlled human data found here.

Natural sources

Myrcene is a common plant emission rather than a rarity. PubChem's compiled sources record it in oil of bay, verbena, and hop, in lemongrass, cypress, artemisia, orange and lemon oils, and in balsam fir and other conifer oils, and note that it is released as a gas from many plant species into the atmosphere [2]. Hops are its signature source: in a 2025 analysis of steam-distilled oils from fresh hop cones, myrcene ran from 27.8 to 48.15 percent of the oil and was the most abundant monoterpene, ahead of the sesquiterpenes alpha-humulene at 19.52 to 24.98 percent and beta-caryophyllene at 8.47 to 13.73 percent [5]. The mango association comes from its presence in the fruit's aroma, which the flavor description above reflects [1]. Cannabis produces myrcene too, often as its dominant terpene, but at far lower concentrations than hop oil. IARC lists foods, medicinal products, forest air, and consumer products as the main routes of human exposure [6].

Boiling point and vaporization

PubChem records myrcene's boiling point as 167 °C from the Hazardous Substances Data Bank, 166 to 167 °C from JECFA, and 332.6 °F from CAMEO Chemicals [2]. This profile uses 167 °C (333 °F). It is among the lowest-boiling common terpenes, about 9 °C below limonene, which is why hop aroma is so easily lost in a long boil and why brewers add aroma hops late. The same volatility applies to any heated product. In a study that heated pure myrcene, limonene, and linalool under conditions simulating dabbing, methacrolein rose from 131 parts per billion per dose at 403 °C to 185 at 526 °C, and benzene appeared only at the highest temperature tested [7]. Myrcene evaporates intact more than 200 °C below the point where those breakdown products appear.

Safety and regulation

Myrcene is the one common terpene with a formal cancer classification. In two-year studies, the US National Toxicology Program gave rats and mice 0.25, 0.5, or 1 gram per kilogram of beta-myrcene daily by gavage and found clear evidence of carcinogenic activity in male rats, from kidney tubule tumors, and in male mice, from liver tumors, with equivocal evidence in females of both species [8]. The compound was not genotoxic in the NTP's assays [8]. On that animal evidence, and with no human data, IARC placed beta-myrcene in Group 2B, possibly carcinogenic to humans, in Monographs Volume 119 [6][9].

The regulatory consequence followed in 2018. The Food and Drug Administration removed synthetic myrcene from the list of permitted synthetic flavoring substances at 21 CFR 172.515 because the Delaney Clause forbids listing an additive shown to induce cancer in animals, while stating in the same rule that its scientific analysis found these substances "do not pose a risk to public health under the conditions of their intended use," and that each has a natural counterpart in food that the rule does not touch [10]. Myrcene is absent from the section today [11]. The doses that produced tumors were thousands of times above dietary exposure.

Industries and uses

Fragrance: myrcene is a fragrance raw material and an intermediate for other aroma chemicals, used sparingly on its own because of its plastic note [1]. Culinary: it is the largest component of hop oil and therefore central to beer aroma, and its flavor at parts-per-million levels is woody, citrus, and mango-like [1][5]; synthetic myrcene is no longer a permitted food additive in the United States, while the natural form in hops, herbs, and fruit is unaffected [10]. Aromatherapy: it is a major constituent of several essential oils used in the practice, including bay and lemongrass [2].