Linalool

Aroma and sensory profile

Linalool is the floral note that reads as clean rather than heady. Fragrance references type it floral and describe the neat material as citrus, floral, sweet, rosewood, woody, green, and faintly blueberry-like; its flavor at 10 parts per million is citrus, orange, lemon, floral, waxy, aldehydic, and woody [1]. That range is why it turns up in so many places at once: it is the lavender in lavender, the soft side of coriander, and a background sweetness in citrus and tea.

Linalool is chiral, and the two forms are sold separately. The (R)-(-) form, laevo-linalool or licareol, is described as fresh, floral, woody, natural, and deep lavender [2]. The (S)-(+) form, dextro-linalool or coriandrol, is described as sweet, floral, petitgrain, and lavender [3]. Both are lavender-like by these descriptions, and the trade names hint at their natural associations, but the sources reviewed here do not quantify which form dominates in lavender oil versus coriander oil, so this profile does not assign one fruit or flower to each enantiomer. One human study found the two forms differ in physiological effect, described below [6].

Effects and research

Linalool has human data, which most terpenes lack. In a 2006 study, 24 volunteers under experimental stress inhaled either (R)-(-)-linalool or (S)-(+)-linalool. Both enantiomers lowered salivary cortisol, a stress marker, and the (R)-(-) form also relieved the stress response in heart rate [6]. The study is small and single-session, but it is a controlled test of the pure compound by inhalation in people, and it shows the two mirror-image forms are not interchangeable.

The mechanism has been probed in mice. Linalool odor reduced anxiety-like behavior in the light-dark box and elevated plus maze tests without impairing movement; the effect vanished in mice that could not smell, showing it ran through olfactory input rather than absorption, and it was blocked by flumazenil, a benzodiazepine-site antagonist, pointing to GABA-A receptor signaling [7]. That places inhaled linalool's calming effect on the same receptor family as benzodiazepine drugs, at least in mice.

Two things the evidence does not support: that linalool treats clinical anxiety or insomnia in people, which no trial reviewed here tested, and that oral or topical doses reproduce the inhalation findings. Studies of lavender oil blends cannot be attributed to linalool alone, since lavender oil carries comparable linalyl acetate [8].

Natural sources

Linalool occurs in more than 200 essential oils from herbs, leaves, flowers, and wood, as a constituent of lavender, bergamot, rosewood, and coriander oils, and in fruits including apples, citrus, and grapes [4]. Two sources carry it in bulk. Coriander seed oil is 60 to 80 percent linalool, with geraniol, terpinen-4-ol, and alpha-terpineol as minor companions [5]. Rosewood oil typically contains 75 to 85 percent [4]. Lavender, its best-known source, is not its richest: across commercial and cultivated Lavandula angustifolia oils, linalool ran from 20 to 45 percent and linalyl acetate from 20.79 to 39.91 percent, the two together defining the oil [8]. The same compound is present in cannabis at far lower levels than any of these oils.

Boiling point and vaporization

PubChem compiles linalool's boiling point as 198 °C from the CRC Handbook of Chemistry and Physics and from JECFA, 198 to 200 °C from the ILO-WHO chemical safety card, and 194 to 197 °C from the Human Metabolome Database [4]. This profile uses 198 °C (388 °F). It boils about 30 °C above myrcene and 20 °C above limonene, which is why linalool survives cooking and distillation better than either and lingers in a heated oil after the lighter citrus notes have left. In a study that heated pure linalool, myrcene, and limonene 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 [9]. Those temperatures are roughly double linalool's boiling point.

Safety and regulation

Linalool is listed by the US Food and Drug Administration among synthetic flavoring substances generally recognized as safe for their intended use in food, at 21 CFR 182.60 [10]. Its documented hazard is skin sensitization, and as with limonene the culprit is oxidation. Fresh linalool has low sensitizing potential, but on air exposure it forms hydroperoxides that are potent sensitizers [11]. In consecutive patch testing of dermatitis patients, 11.7 percent reacted to hydroperoxides of linalool, a higher rate than for limonene in the same series [11], and a 2024 review reports prevalence up to 20 percent in some populations [12]. Products that have been open for months are the concern, not fresh ones. No inhalation toxicity study in humans was found beyond the small stress trial above.

Industries and uses

Fragrance: linalool is one of the most widely used floral materials in perfumery, valued for its clean lavender-citrus character and sold in both enantiomeric forms [1][2][3]. Cosmetics: it appears in soaps, lotions, and cleansers as a scent component, which is the exposure route behind the sensitization data [11][12]. Culinary: it holds FDA flavoring status and contributes citrus and floral notes at parts-per-million levels [1][10]. Aromatherapy: lavender and coriander oils, both linalool-rich, are staples of the practice, and the inhalation studies above are the closest the evidence comes to testing that use [6][7].