Cedrene

Aroma and sensory profile

Cedrene is the smell of a pencil sharpener. Fragrance references type alpha-cedrene woody with medium strength and describe it neat as woody, cedar, sweet, and fresh [1]. It is the cleaner, brighter half of cedarwood oil, the part that reads as freshly cut wood rather than as the soft, dry, persistent base that cedrol supplies, and the two together are why cedarwood oil smells the way a cedar closet does. Beta-cedrene, its isomer with the double bond moved outside the ring, accompanies it at a fraction of the level and carries no separate panel description [2].

The molecule is a tricyclic sesquiterpene hydrocarbon with four stereocenters and it is chiral. The natural material is (−)-alpha-cedrene, the enantiomer PubChem and the NIST reference spectra record for cedarwood [3]. No panel description of (+)-alpha-cedrene was found, so no claim about how the two enantiomers differ in odor is made here.

Effects and research

No human trial of cedrene was found, and its pharmacology is a single thread. In cultured myotubes and in mice, alpha-cedrene was identified as a ligand of the olfactory receptor MOR23 expressed in muscle; treated mice showed greater skeletal muscle mass, protein content, myofiber cross-sectional area, and strength than controls, through a cAMP-PKA-CREB pathway dependent on that receptor [5]. It is a striking result, that a cedar odorant can act on an olfactory receptor in muscle, but it is one study in one model and has not been replicated in people.

The rest of what is known comes from the Research Institute for Fragrance Materials, whose 2025 assessment found cedrene not genotoxic, not expected to be photoirritating or photoallergenic, set a no-expected-sensitization-induction level of 3,500 micrograms per square centimeter, and placed repeated-dose and reproductive exposures below the threshold of toxicological concern for its structural class [4]. That is a clean profile, but it is a fragrance safety profile, not evidence of any effect.

Natural sources

Cedrene is a cedarwood terpene. Fragrance databases log alpha-cedrene at 30.7 percent in Texas cedarwood oil, 26.4 percent in Chinese cedarwood oil, 21.1 percent in Virginia cedarwood oil, and 20.5 percent in Atlas cedarwood oil, with 0.61 percent in calamus root oil and traces in ayou wood, basil, clary sage, and cypress [1]; beta-cedrene follows at 5 to 9 percent in the same four oils [2]. Those oils come from the wood of Juniperus virginiana and Juniperus mexicana in North America and Cupressus funebris in China, and cedrol from the same trees is recorded in Cedrus atlantica and Cupressus sempervirens as well [6]. Cedrene is therefore not a true cedar terpene so much as a juniper and cypress one; the "cedar" of pencils and closets is eastern red cedar, a juniper. In cannabis cedrene is a trace sesquiterpene, occasionally reported and more often absent.

Boiling point and vaporization

No measured boiling point for cedrene appears in PubChem or in a primary paper found for this profile, so none is listed. PubChem carries no experimental boiling point for (−)-cedrene [3], the NIST WebBook lists only spectra for it, and fragrance references quote 261 to 262 °C at 760 mmHg [1], an industry value not adopted here; the 262 °C the site previously listed was that figure. What can be said is that cedrene is a fifteen-carbon hydrocarbon sesquiterpene, in the same volatility band as caryophyllene and humulene, which is why cedarwood oil is a base material. It is a combustible liquid, flagged as flammable by about a third of European notifications [3]. No thermal degradation study of cedrene was found.

Safety and regulation

Cedrene is not listed by name in the FDA flavoring tables at 21 CFR 172.515; it enters commerce as the main constituent of cedarwood oils, and its fragrance use rests on the 2025 Research Institute for Fragrance Materials assessment, which found it not genotoxic, not phototoxic, and safe for sensitization at a no-expected-sensitization-induction level of 3,500 micrograms per square centimeter [4]. No cancer classification applies.

Its hazard record is environmental and physical rather than dermal. Under Europe's classification inventory, 95 percent of notifications flag (−)-cedrene as an aspiration hazard and 96 to 98 percent as very toxic to aquatic life with long-lasting effects, with flammability in 29 percent and no skin sensitization or irritation code above threshold [3]. The two practical cautions are the hydrocarbon ones: do not swallow neat cedarwood oil, and do not let it reach a drain.

Industries and uses

Fragrance: cedrene is the fresh woody body of cedarwood oil and a foundation material in woody, fougère, and masculine accords, used both as the oil and as a fractionated isolate, and valued for its clean safety profile at fragrance use levels [1][4]. Aromatherapy: cedarwood oils from Virginia, Texas, and China are its carriers; the aspiration hazard and the near-absent sensitization signal are the relevant notes [3][6].