Ledol is an oxygenated sesquiterpene associated with Labrador-tea and rock-rose style essential oils, including cistus records already present in the AromaForge archive. The current evidence base is uneven: identity and occurrence are strong, but most biological discussion comes from whole-plant or whole-oil literature rather than isolated ledol trials. A few constituent-level papers do exist, mainly around structure assignment and insect-feeding context, and safety-oriented reviews repeatedly flag toxicity concerns for ledol-rich traditional preparations. For AromaForge, ledol is best presented as a chemistry and safety-relevant sesquiterpene rather than a clinically supported wellness active.
Chemical identity and composition
PubChem resolves ledol to CID 11074994 with formula C15H26O, while NIST lists ledol under CAS 577-27-5. In the archive's cistus record, ledol is reported at 2.85% to 3.51% across sampled batches, which supports it as a recurring oxygenated sesquiterpene marker in Cistus ladanifer oil rather than a rare trace constituent.
Aroma and practical use
- Use the recorded woody, camphoraceous, herbal, herbaceous descriptors to explore a blend's scent character; perceived strength also depends on the other ingredients.
- Read the route, preparation and experimental context before using a study finding to choose an oil.
Reported benefits and effects
Findings retain their study context. An animal or laboratory result describes that experiment.
A 2000 NMR study isolated a sesquiterpene alcohol from Renealmia chrysotrycha and established its relative stereochemistry as ledol, resolving earlier literature ambiguity around the structure.
A 2000 NMR study isolated a sesquiterpene alcohol from Renealmia chrysotrycha and established its relative stereochemistry as ledol, resolving earlier literature ambiguity around the structure.
This reference does not establish a therapeutic result or a safe use level for a custom oil blend.
A 2006 potato study identified ledol among leaf-surface sesquiterpene alcohols and tested it in Colorado potato beetle feeding assays; the abstract specifically reports attractant activity for kunzeaol, not for ledol.
A 2006 potato study identified ledol among leaf-surface sesquiterpene alcohols and tested it in Colorado potato beetle feeding assays; the abstract specifically reports attractant activity for kunzeaol, not for ledol.
This experimental finding does not establish benefit, dose or safety in people using this blend.
A 2013 review of Rhododendron tomentosum summarized biological activity and toxicology for the plant and its essential oil, highlighting ledol as part of the chemistry behind why the plant has both traditional use and toxicity concerns.
A 2013 review of Rhododendron tomentosum summarized biological activity and toxicology for the plant and its essential oil, highlighting ledol as part of the chemistry behind why the plant has both traditional use and toxicity concerns.
This reference does not establish a therapeutic result or a safe use level for a custom oil blend.
In the archive's cistus evidence base, ledol was reported at 2.85%, 3.41%, and 3.51% across sampled Cistus ladanifer oil batches, supporting its relevance as a real profile constituent.
In the archive's cistus evidence base, ledol was reported at 2.85%, 3.41%, and 3.51% across sampled Cistus ladanifer oil batches, supporting its relevance as a real profile constituent.
This reference does not establish a therapeutic result or a safe use level for a custom oil blend.
Use concerns and concentration limits
Sensitization concernNot flagged
Not flagged in the current model. This is not proof of absence or unrestricted safety.
Phototoxicity concernNot flagged
Not flagged in the current model. This is not proof of absence or unrestricted safety.
Oxidation concernNot flagged
Not flagged in the current model. This is not proof of absence or unrestricted safety.
Penetration enhancementNot flagged
Not flagged in the current model. This is not proof of absence or unrestricted safety.
No numeric constituent-specific use limit is available here. Missing is not an unrestricted-use clearance.
A PubMed-indexed Labrador tea review states the beverage should not be consumed more than once daily because of ledol and grayanotoxin toxicity, indicating that ledol-rich preparations carry recognized traditional-use safety concerns.
This reference does not establish a therapeutic result or a safe use level for a custom oil blend.
No direct public citation is attached to this entry.
No constituent-specific human dermal limit, IFRA restriction, or controlled tolerability trial for isolated ledol was verified in the reviewed public sources.
This reference does not establish a therapeutic result or a safe use level for a custom oil blend.
No direct public citation is attached to this entry.
Constituents it may interact with
No constituent-pair interaction is recorded for this identity. The report does not assume either amplification or incompatibility.
How the effects were investigated
insect ecology signal
The clearest direct ledol-specific functional paper located involved potato-beetle feeding assays, which places the constituent in plant-insect ecology rather than human pharmacology.
This experimental finding does not establish benefit, dose or safety in people using this blend.
No direct public citation is attached to this entry.
structure defined aromadendrane alcohol
An NMR study from Renealmia chrysotrycha clarified the relative stereochemistry of ledol, helping distinguish it from related aromadendrane sesquiterpene alcohols in analytical work.
This reference does not establish a therapeutic result or a safe use level for a custom oil blend.
No direct public citation is attached to this entry.
What this report cannot establish
- A reported constituent percentage does not establish an effective human therapeutic dose or the amount absorbed into the body.
- The presence of a constituent does not guarantee a clinical benefit, rash treatment or sleep improvement from a custom blend.
- An unflagged concern or missing use limit does not establish safety for ingestion, inhalation, skin exposure or a particular person.
- A candidate constituent interaction does not establish that two oils amplify one another at the selected proportions.
- Constituent descriptors alone do not establish a precise top, heart or base lifetime in a finished blend.
Known data gaps (6)
- No human clinical evidence for isolated ledol was verified in this pass.
- Most activity claims around ledol are still inferred from ledol-containing plants or essential-oil mixtures rather than isolated constituent testing.
- No IFRA standard, Tisserand & Young dermal maximum, or peer-reviewed dermal-limit/phototoxicity/penetration-enhancer study specific to isolated ledol could be located in this verification pass; the ledol/grayanotoxin CNS-toxicity concern documented for Rhododendron tomentosum preparations is a whole-plant traditional-use finding, not an isolated-constituent dermal safety citation, so dermal_limit_pct was reset to null.
- Second pass (2026-07-13): supplier REACH/CLP SDS for ledol (CAS 577-27-5) confirms Acute Tox. 4 (H302) classification but explicitly lists sensitization and skin-irritation data as unavailable, and gives no dermal exposure limit; searches for RIFM/ECHA CLH data and a viridiflorene/ledene sibling-certificate cross-check found nothing further. dermal_limit_pct, sensitizing, and phototoxic remain unresolved (null).
- No constituent-specific numeric dermal reference is available here.
- Some findings do not record an explicit exposure route; consult the linked study before applying them to a use.