Essential Oils & Aromatherapy · Essential oil
Niaouli Oil
Melaleuca quinquenervia and Melaleuca viridiflora · also called Niaouli, gomenol, broad-leaved paperbark oil
Niaouli oil is a fresh, camphor-like essential oil distilled from the leaves of a tea tree relative. It is used in French aromatherapy for skin and chest, and it is said to protect skin during radiotherapy. The research is thin: one old French report we could not read, and lab and mouse studies. The main cautions: never swallow it, and keep it away from the faces of babies and young children.
General information, not medical advice. Last substantive update · Not medically reviewed. A named clinician has not signed off on this page. How this page is made
About Niaouli Oil
Niaouli oil is a cineole-rich leaf oil from tea tree relatives. It is best known in France for chest and skin use, including a reputation for protecting skin during breast radiotherapy. That claim rests on one old French report we could not read and no controlled trial. Everything else is dish, cell and mouse work. Safety comes first: do not swallow it, keep it away from children's faces and from pets, and ask a doctor in pregnancy or before use on treated skin.
The radiotherapy skin claim
In France, niaouli oil has a reputation for protecting skin during breast radiotherapy. The source is a 2004 French clinical report (Phytotherapie). Crossref confirms the title, author, journal and date, but we could not open the abstract or text, so we do not know how many women took part, how it was designed or what it found. No controlled trial of niaouli for this was found in PubMed.
The only controlled trial we found is a 2014 US pilot of 24 women comparing an unnamed essential oil mixture with the usual ointment. It found no significant difference. It is too small to show a benefit or a harm, and the abstract does not name niaouli.
Radiotherapy skin is already damaged, and Poison Control says not to put essential oils on damaged skin. Ask the radiotherapy team before putting anything on treated skin.
What niaouli oil is
Papers use 'niaouli' for two trees, Melaleuca quinquenervia and Melaleuca viridiflora. GBIF lists both as accepted names in the myrtle family. The oil is steam-distilled from the leaves.
It is a mixture. One M. viridiflora oil was 1,8-cineole 35.66%, viridiflorol 14.20%, limonene 11.04%, alpha-terpineol 7.89% and alpha-pinene 7.42%. A second M. quinquenervia chemotype was mostly (E)-nerolidol (48.40%) and linalool (33.30%), and a third mostly 1,8-cineole (52.20%). Bottles can be very different.
Niaouli is a relative of tea tree (M. alternifolia) and cajeput (M. cajuputi), but results do not carry over between them.
What people use it for, and how strong the evidence is
For radiotherapy skin, acne, wounds and colds, no controlled human trial of niaouli oil was found. For skin pigment, cancer cells, enzymes and immune markers, the studies are in dishes or mice.
In the lab, niaouli oil was the best of six oils at helping estradiol cross mouse skin. That does not show what happens on human skin, but it is a reason to ask a pharmacist before layering it with a medicine skin product.
We rate every use insufficient.
The research in one view
No controlled human trial of niaouli oil was found. One French report on radiotherapy skin could not be read. All other results are cell, test-tube or mouse studies.
No dose, strength or way to use the oil is given on this page, and none is known to be safe.
At a glance
Traditional uses history, not proof
- A 1948 French medical article describes 'gomenol', an essence of Melaleuca viridiflora (title only; content not read).
- A 2004 French clinical report describes niaouli oil for skin reactions from breast radiotherapy (title and date verified; details not read).
- The Ndjuka (Maroon) community of French Guiana has taken niaouli into its medicinal plants (2023 interviews).
Studied for research
- Skin reactions from breast radiotherapy, insufficient
- Acne bacteria in a dish (lab nanoemulsion), insufficient
- Germ-killing in the lab, insufficient
- Colds and cough (traditional, no trial), insufficient
- Skin pigment in mouse cells, insufficient
- Lung cancer cells in a dish, insufficient
- Immune markers in mice, insufficient
Main compounds
- 1,8-Cineole, the main compound in most oils
- Viridiflorol, a leading compound in some oils
- (E)-Nerolidol and linalool, leading in a second chemotype
- Limonene, alpha-terpineol and alpha-pinene
Common forms
- Essential oil (steam-distilled from the leaves)
- Diluted skin and chest blends (contents vary by maker)
- Lab nanoemulsion (research only; not a consumer product)
Research links: Poison Control: Essential oils · EMA: Eucalyptus oil (cineole-rich relative) · NCCIH: Tea tree oil · Pet Poison Helpline: Tea tree oil · FDA: Aromatherapy · Niaouli oil composition, M. viridiflora (abstract) · Radiotherapy skin report, Phytotherapie 2004 (record) · Research Library · Genes & Biomarkers Library
What it is and its history
- Accepted scientific name
- Melaleuca quinquenervia and Melaleuca viridiflora
- Naming authority
- (Cav.) S.T.Blake; Sol. ex Gaertn.
- Synonyms
- Name: Gomenol (French name for the oil); Status: Trade/historical name; a 1948 French article uses it for an essence of M. viridiflora
- Common names
- Niaouli (French/English); Broad-leaved paperbark (English); Gomenol (French)
- Family or group
- Myrtaceae (myrtle family), per GBIF.
- Classification
- Plantae > Myrtaceae > Melaleuca > Melaleuca quinquenervia; Melaleuca viridiflora
- Native range
- Australia for M. viridiflora per one 2026 paper; the oil is distilled in several countries.
- Habitat
- Introduced widely; listed as an invasive alien plant in French Guiana savannas in one 2023 study.
- What it looks like
- Part used: The oil is steam-distilled from the leaves (papers read).
- Look-alikes and adulterants
- Name: Tea tree (Melaleuca alternifolia); Note: A close relative whose oil is mostly terpinen-4-ol. Results do not carry over, but it supplies the best safety information for the genus.; Name: Cajeput (Melaleuca cajuputi); Note: Also cineole-rich (64.63% 1,8-cineole in one oil). Different species.; Name: Eucalyptus; Note: A different genus, also cineole-rich; the source of child and seizure cautions that are read across to niaouli.
- Sustainability and conservation
- Not assessed here.
Photographs
Traditional use and history history, not clinical proof
| Tradition or era | Documented use | Source |
|---|---|---|
| French medicine, 1948 | A 1948 French medical article on 'gomenol' (essence of Melaleuca viridiflora) exists; title only, content not read. | Marche J, J Med Chir Prat 1948 |
| French Guiana (Ndjuka Maroons) | Niaouli has been taken into the community's medicinal plants, named, used and traded (2023 interviews). | Theys et al 2023 |
| French radiotherapy skin tradition | A 2004 French clinical report describes niaouli oil for breast radiotherapy skin reactions. Only title and date were verified. | Giraud-Robert 2004, Phytotherapie |
Traditional use shows how it was used. It does not show that it works or is safe today.
What is inside, and how it may work
What it contains and how those compounds act in cells and animals. Laboratory and animal mechanisms are not proven effects in people.
Main compounds
| Compound | Family | Where it is concentrated | Activity studied | Level of evidence |
|---|---|---|---|---|
| 1,8-Cineole (eucalyptol) PubChem 2758 | monoterpene ether | Leaf oil 35.66% (M. viridiflora, Americas); 21.60% and 31.57% (M. quinquenervia); 52.20% (one chemotype) | Main compound in most niaouli oils. Reduced melanin in mouse cells in a dish. Basis of the child and seizure cautions read across from eucalyptus. 22 2 4 23 17 | Laboratory |
| Viridiflorol PubChem 11996452 | sesquiterpene alcohol | Leaf oil 14.20% (M. viridiflora); 14.55% and 13.65% (M. quinquenervia) | Named as a major component; no separate activity read. 22 2 4 17 | Laboratory |
| (E)-Nerolidol PubChem 5284507 | sesquiterpene alcohol | Leaf oil of the nerolidol chemotype 48.40% in one M. quinquenervia oil | Dominant in one chemotype. No separate activity read. 23 17 | Laboratory |
| Linalool PubChem 6549 | monoterpene alcohol | Leaf oil of the nerolidol chemotype 33.30% in the same oil | Named; no separate activity read. The French patch-test study lists oxidised linalool among its screening substances. 23 1 17 | Laboratory |
| alpha-Terpineol PubChem 17100 | monoterpene alcohol | Leaf oil 7.89% (M. viridiflora); 13.73% (M. quinquenervia) | Reduced melanin in mouse cells in a dish (with 1,8-cineole and alpha-pinene). 22 2 17 | Laboratory |
| alpha-Pinene PubChem 6654 | monoterpene | Leaf oil 7.42% (M. viridiflora); 15.93% (M. quinquenervia) | Reduced melanin in mouse cells in a dish. 22 2 17 | Laboratory |
| Limonene PubChem 22311 | monoterpene | Leaf oil 11.04% (M. viridiflora) | Named as a major component; no separate activity read. 22 17 | Laboratory |
Mechanisms, receptors and pathways
| Target or pathway | Gene or receptor | What was found | Level |
|---|---|---|---|
| Acetylcholinesterase | ACHE | Moderate blocking in a test tube (IC50 65.98 micrograms per mL). 22 | Laboratory research |
| Tyrosinase and oxidative stress in melanoma cells | TYR | The oil and three compounds lowered melanin and tyrosinase activity in mouse cells. 2 | Laboratory research |
| Skin permeation | n/a | Niaouli oil helped estradiol cross mouse skin in a dish better than five other oils. 11 12 | Laboratory research |
| Predicted targets in lung cancer cells (computer model) | ESR1, CASP3, PPARG, PTGS2 | A computer analysis predicted these targets; cell-cycle arrest and cell death were seen in a dish. Prediction, not proof. 4 | In silico |
| Placental hormone release | P2X7 receptor (not activated) | Hormone release changed in human placental cells in a dish; the cell-death receptor was not activated. 5 | Laboratory research |
| T-cell and macrophage activity (mice) | CD25, IFN-gamma, TNF-alpha, IL-12 | Raised in mice given injected oil. 13 | Animal research |
Absorption, metabolism and elimination
- Absorption
- Not established in the sources read.
- Distribution
- Not established.
- Metabolism
- Not established.
- Elimination
- Not established.
- Bioavailability
- Not established. Only mouse-skin permeation of another drug was tested.
Isolated compounds versus whole extracts
Niaouli oil is a mixture, and its makeup varies with chemotype, place, season and distillation. Whole niaouli oil beat its main compounds alone for helping estradiol cross mouse skin, and the placental study found single compounds acted differently from whole oils. Findings for one bottle do not carry to another.
Nutritional composition
Niaouli oil is not a nutrient and is not something to swallow.
9 not enough evidence
What is Niaouli Oil good for?
The uses people ask about and how strong the evidence is for each. Read the certainty label first: nothing here is better than insufficient. There is no controlled human trial of niaouli oil.
Benefits, one by one
Each card is a research question, not a promise. Tap a goal to filter. Open a card to see the studies, doses and limits.
Skin burns from breast radiotherapy (radiodermatitis)
Not enough evidenceIn France, niaouli oil has a reputation for protecting skin during breast radiotherapy, based on a 2004 French report. We could not read its details, and no controlled trial of niaouli for this was found. A small US trial of an unnamed oil mixture found no difference from the standard ointment.
3 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
One French-language clinical report (details not read: size and design unknown, an unconfirmed secondary mention says about 20 women) and one small randomised pilot of 24 women with an unnamed essential oil mixture.
Results
The 2004 report is described as favourable in tradition, but we could not read its results. The 2014 pilot (24 women, oil mixture not named) found no significant difference from the usual ointment for skin reactions, quality of life or satisfaction.
Effect sizes as reported
Not available from sources we read.
Why this rating
No controlled trial of niaouli was found and the one niaouli report could not be read. The only controlled trial is tiny and its oil mixture is not named.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
Women having breast radiotherapy.
Limits
Size, design and results of the French report are unverified. Not blinded as far as we know. A small pilot cannot show benefit or harm.
Why researchers looked
Radiotherapy can leave the skin red, sore and peeling, so people look for soothing options.
Traditional use
A French clinical report (2004, Phytotherapie) describes niaouli oil for radiotherapy skin reactions in breast cancer. This is the source of the French tradition.
Proposed mechanism Preliminary mechanism
Not established.
A proposed mechanism does not show that the effect happens in people.
Irradiated skin is already damaged. Poison Control says not to put oils on damaged skin. Talk to the radiotherapy team before putting anything on treated skin.
Acne bacteria (lab nanoemulsion)
Not enough evidenceIn a dish, a lab-made niaouli nanoemulsion slowed two skin bacteria linked to acne, and more oil passed through skin samples than plain oil. No person was tested.
1 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
None. Dish and skin-sample work.
Results
All the nanoemulsion formulas slowed Propionibacterium acnes and Staphylococcus epidermidis in a dish. Skin-sample (ex vivo) permeation improved with nanoemulsion compared with neat oil.
Effect sizes as reported
No effect sizes in the abstract.
Why this rating
Lab only, with a special formula that is not a consumer product.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
Not applicable.
Limits
Special formula with added solvents; no human skin trial.
Why researchers looked
Researchers look for plant oils that might help acne-prone skin.
Traditional use
Niaouli is used in French skin blends, but no trial supports acne use.
Proposed mechanism Preliminary mechanism
Not established. The study tested delivery and germ-slowing in a dish.
A proposed mechanism does not show that the effect happens in people.
Plain oil can irritate skin (see Safety).
Germ-killing in the lab (bacteria and moulds)
Not enough evidenceIn dishes, niaouli leaf oil slowed some bacteria and a mould, but at very high levels, and it killed bacteria taken from infected dog wounds. Dish results do not show an effect on skin or in the body.
2 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
None. Lab work on bacteria and moulds.
Results
M. viridiflora leaf oil needed 4000 micrograms per mL to slow Listeria monocytogenes, Enterococcus faecium and Aspergillus niger, and its antioxidant effect was weak. A separate study found niaouli oil killed bacteria from dog wounds (MBC/MIC 0.015 to 0.5 microlitres per mL).
Effect sizes as reported
Not applicable.
Why this rating
Lab only. Methods differ and cannot be compared with use on a person.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
Not applicable.
Limits
Dish tests; one study was partly by an oil company employee.
Why researchers looked
Plant oils are often tested for germ-killing as a first screen.
Traditional use
Niaouli oil is traditionally used on skin and chest, but no trial supports a germ-killing use in people.
Proposed mechanism Preliminary mechanism
Not established.
A proposed mechanism does not show that the effect happens in people.
A germ-killing result in a dish does not make it safe to put on wounds.
Colds, cough and blocked nose (traditional)
Not enough evidenceNiaouli oil is traditionally used in chest blends, but no controlled human trial of niaouli oil for colds, cough or congestion was found. Another cineole-rich oil, eucalyptus, is accepted by the EU only for traditional use.
1 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
No human study of niaouli oil.
Results
None for niaouli. The EMA accepts eucalyptus oil for coughs on traditional use only and notes the trials it looked at tested 1,8-cineole, not the oil.
Effect sizes as reported
Not applicable.
Why this rating
No trial. The eucalyptus finding does not carry over.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
Not applicable.
Limits
Absence of trials is not proof of no effect, but no benefit has been shown.
Why researchers looked
Niaouli is rich in 1,8-cineole, a compound found in many chest-rub oils.
Traditional use
Used in French aromatherapy and chest rubs; no source we read documents the tradition in detail.
Proposed mechanism Preliminary mechanism
Not established for niaouli.
A proposed mechanism does not show that the effect happens in people.
Cineole-rich oils carry child and seizure cautions (see Safety). Never near the nose or face of babies and young children.
Skin pigment (mouse melanoma cells)
Not enough evidenceIn mouse melanoma cells in a dish, niaouli oil and its main compounds lowered melanin production. The authors suggest a skin-whitening use, but nobody has tested it on skin.
1 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
None. Mouse cancer cells in a dish.
Results
Lowered melanin and tyrosinase activity and changed antioxidant markers.
Effect sizes as reported
Not applicable.
Why this rating
Cells in a dish, with a cancer cell line.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
Not applicable.
Limits
No skin or human test.
Why researchers looked
Researchers screen plant oils for pigment-lowering effects.
Traditional use
Not applicable.
Proposed mechanism Preliminary mechanism
The oil and 1,8-cineole, alpha-pinene and alpha-terpineol lowered tyrosinase (a pigment enzyme) and shifted antioxidant markers in cells.
A proposed mechanism does not show that the effect happens in people.
None for lab work.
Lung cancer cells in a dish
Not enough evidenceNiaouli leaf oil from Egypt killed human lung cancer cells in a dish and a computer analysis predicted targets. This is lab work only and is not a treatment or prevention claim.
1 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
None.
Results
Toxic to A549 lung cancer cells (IC50 18.09 micrograms per mL); selectivity index 4.30.
Effect sizes as reported
IC50 18.09 micrograms per mL.
Why this rating
Cells and computer modelling only; the authors call for animal studies first.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
Not applicable.
Limits
An oil that kills cells in a dish can harm healthy cells too. Do not read this as a cancer treatment.
Why researchers looked
Researchers screen plant oils for cell-killing activity.
Traditional use
Not applicable.
Proposed mechanism Preliminary mechanism
Cell death, slowed movement and cell-cycle arrest in A549 cells; computer modelling predicted targets including ESR1.
A proposed mechanism does not show that the effect happens in people.
Cell toxicity in a dish is not a safety measure for use.
Immune cell activity (mice, injected oil)
Not enough evidenceIn mice, injected niaouli oil raised some T-cell and macrophage activity markers but not antibodies. This is animal work with an injected route; it does not apply to using the oil on skin or breathing it.
1 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
None.
Results
Raised T-cell markers and macrophage signals; no change in antibody response.
Effect sizes as reported
Not applicable.
Why this rating
Mouse work with injection into the abdomen.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
Not applicable.
Limits
No human or skin-route data.
Why researchers looked
Researchers tested whether the oil changes immune signals.
Traditional use
Not applicable.
Proposed mechanism Preliminary mechanism
Higher T-cell activation and macrophage signals (TNF-alpha, IL-12) in mice.
A proposed mechanism does not show that the effect happens in people.
Injection is not a use route; this is not safety data.
Memory-related enzyme (test tube)
Not enough evidenceIn a test tube, niaouli oil blocked an enzyme (acetylcholinesterase) that some memory medicines target, at a moderate level. It is not a memory test in people.
1 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
None.
Results
Moderate enzyme blocking in a test tube.
Effect sizes as reported
IC50 65.98 +/- 1.0 micrograms per mL.
Why this rating
Enzyme assay only.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
Not applicable.
Limits
No cells, animals or people tested for memory.
Why researchers looked
A standard lab screen for oils that might affect memory enzymes.
Traditional use
Not applicable.
Proposed mechanism Preliminary mechanism
The oil blocked acetylcholinesterase with an IC50 of 65.98 micrograms per mL.
A proposed mechanism does not show that the effect happens in people.
None.
Helping other substances cross skin (lab)
Not enough evidenceIn mouse skin in a dish, niaouli oil was the best of six oils at helping the hormone estradiol pass through skin. It is a drug-delivery finding and also a caution: niaouli oil may change how other skin products are absorbed.
2 studiesNot covered. This page gives no amounts and no way to use the oil.
Studies, doses and limits
What the trials found
None. Mouse skin in a dish.
Results
Niaouli oil was the best permeation promoter of six oils for estradiol; a second paper found four niaouli oils differed in composition and in effect.
Effect sizes as reported
Not applicable.
Why this rating
Mouse skin in a dish; not tested in people.
Form and dose studied
Not covered. This page gives no amounts and no way to use the oil.
Who was studied
Not applicable.
Limits
No human skin data.
Why researchers looked
Researchers look for natural boosters for skin patches and gels.
Traditional use
Not applicable.
Proposed mechanism Preliminary mechanism
Terpenes in the oil are thought to help other molecules pass through skin; whole oil beat its main parts alone.
A proposed mechanism does not show that the effect happens in people.
Not a benefit. It is a reason not to layer niaouli oil under or over medicine skin products without asking a pharmacist.
Connections to the rest of health
How Niaouli Oil connects to the rest of our health knowledge graph. Every link says what kind of connection it is. A safety link (for example to the liver) is a warning, not a benefit. A study that merely mentions a topic never creates a benefit link.
Explore every connection: goals, body systems, organs, symptoms, genes
A. Wellness goals
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Healthy Skin | Traditional use | Not enough evidence | Skin burns from breast radiotherapy (radiodermatitis): In France, niaouli oil has a reputation for protecting skin during breast radiotherapy, based on a 2004 French report. We could not read its details, and no controlled trial of niaouli for this was found. A small US trial of an unnamed oil mixture found no difference from the standard ointment. | 8 9 16 |
| Healthy Skin | Not enough evidence | Acne bacteria (lab nanoemulsion): In a dish, a lab-made niaouli nanoemulsion slowed two skin bacteria linked to acne, and more oil passed through skin samples than plain oil. No person was tested. Skin pigment (mouse melanoma cells): In mouse melanoma cells in a dish, niaouli oil and its main compounds lowered melanin production. The authors suggest a skin-whitening use, but nobody has tested it on skin. | 19 2 11 12 | |
| Immune Support | Not enough evidence | Germ-killing in the lab (bacteria and moulds): In dishes, niaouli leaf oil slowed some bacteria and a mould, but at very high levels, and it killed bacteria taken from infected dog wounds. Dish results do not show an effect on skin or in the body. Immune cell activity (mice, injected oil): In mice, injected niaouli oil raised some T-cell and macrophage activity markers but not antibodies. This is animal work with an injected route; it does not apply to using the oil on skin or breathing it. | 22 18 13 | |
| Breathing Support | Traditional use | Not enough evidence | Colds, cough and blocked nose (traditional): Niaouli oil is traditionally used in chest blends, but no controlled human trial of niaouli oil for colds, cough or congestion was found. Another cineole-rich oil, eucalyptus, is accepted by the EU only for traditional use. | 3 |
| Cellular Protection | Not enough evidence | Lung cancer cells in a dish: Niaouli leaf oil from Egypt killed human lung cancer cells in a dish and a computer analysis predicted targets. This is lab work only and is not a treatment or prevention claim. | 4 | |
| Memory Support | Not enough evidence | Memory-related enzyme (test tube): In a test tube, niaouli oil blocked an enzyme (acetylcholinesterase) that some memory medicines target, at a moderate level. It is not a memory test in people. | 22 |
B. Body systems
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Integumentary System | Biological association | Not enough evidence | Studied for: Skin burns from breast radiotherapy (radiodermatitis) Studied for: Acne bacteria (lab nanoemulsion) | 8 9 16 19 22 18 2 11 12 |
| Immune System | Biological association | Not enough evidence | Studied for: Germ-killing in the lab (bacteria and moulds) Studied for: Immune cell activity (mice, injected oil) | 22 18 13 |
| Respiratory System | Biological association | Not enough evidence | Studied for: Colds, cough and blocked nose (traditional) Studied for: Lung cancer cells in a dish | 3 4 |
| Nervous System | Biological association | Not enough evidence | Studied for: Memory-related enzyme (test tube) | 22 |
E. Health conditions
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Contact dermatitis | Adverse effect or risk | Documented risk | Poison Control and a French case series describe skin allergy from essential oils; niaouli was not named in the abstract. Preparation or compound: Essential oils on the skin (general) |
16 1 |
I. Biomarkers
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Radiotherapy skin reaction (weekly clinical grading) | Biological association | Not enough evidence | Measured in trials: unchanged vs standard ointment (pilot, oil mixture not named). A lab change is not the same as a health benefit. | 9 |
| Growth of acne bacteria in a dish | Biological association | Not enough evidence | Measured in trials: lowered (in a dish). A lab change is not the same as a health benefit. | 19 |
| Melanin and tyrosinase activity (cells) | Biological association | Not enough evidence | Measured in trials: lowered (in a dish). A lab change is not the same as a health benefit. | 2 |
| Acetylcholinesterase activity (lab test) | Biological association | Not enough evidence | Measured in trials: lowered (in a test tube). A lab change is not the same as a health benefit. | 22 |
L. Active compounds
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| 1,8-Cineole (eucalyptol) | Biological association | Laboratory | Main compound in most niaouli oils. Reduced melanin in mouse cells in a dish. Basis of the child and seizure cautions read across from eucalyptus. Preparation or compound: Leaf oil |
22 2 4 23 17 |
| Viridiflorol | Biological association | Laboratory | Named as a major component; no separate activity read. Preparation or compound: Leaf oil |
22 2 4 17 |
| (E)-Nerolidol | Biological association | Laboratory | Dominant in one chemotype. No separate activity read. Preparation or compound: Leaf oil of the nerolidol chemotype |
23 17 |
| Linalool | Biological association | Laboratory | Named; no separate activity read. The French patch-test study lists oxidised linalool among its screening substances. Preparation or compound: Leaf oil of the nerolidol chemotype |
23 1 17 |
| alpha-Terpineol | Biological association | Laboratory | Reduced melanin in mouse cells in a dish (with 1,8-cineole and alpha-pinene). Preparation or compound: Leaf oil |
22 2 17 |
| alpha-Pinene | Biological association | Laboratory | Reduced melanin in mouse cells in a dish. Preparation or compound: Leaf oil |
22 2 17 |
| Limonene | Biological association | Laboratory | Named as a major component; no separate activity read. Preparation or compound: Leaf oil |
22 17 |
Each connection is stored with the ingredient, the connected record, the kind of connection, the evidence status, the supporting studies, the preparation or compound involved, and a review date (last reviewed October 25, 2026).
The evidence
The research centre for Niaouli Oil. Every record here was checked against PubMed or the publisher's page; we never list a study we have not verified.
Evidence by outcome
Bars show how many studies we found for each outcome, not how well it works. People are added up across trials only (reviews are not added, to avoid double counting).
How we rate evidence
High certainty
Several well-run trials or reviews agree; further research is unlikely to change the picture much.
Moderate certainty
Good trials point the same way, but some doubt remains.
Low certainty
Small, short or inconsistent trials. The finding could change with better research.
Very low certainty
Very little or very weak human data. Treat as a possibility only.
Mixed findings
Trials or reviews disagree with each other.
Not enough evidence
Not enough human research to say either way.
Evidence against
Good research found no benefit, or found harm.
We take the reviewers' own risk-of-bias and GRADE statements where they exist, and otherwise judge from study size, design, consistency, directness and whether a product matches what is sold. Many publications do not make evidence high. Method note: We read the abstracts of 15 PubMed papers (a 1948 French article is title only), confirmed a 2004 French article's record through Crossref (text not read), read the EMA, Poison Control, NCCIH, Pet Poison Helpline and FDA pages, checked both tree names in GBIF and seven compounds in PubChem.
Study library: every study we checked 25
| Study | Design | People | Product, dose, length | Result |
|---|---|---|---|---|
| Barbaud 2023 Allergic contact dermatitis from essential oil in consumer products: Mode of uses and value of patch tests with an essential oil series. Results of a French study of the DAG. Contact Dermatitis · PMID 37403438 · DOI |
Case series Human |
42 Adults with allergic contact dermatitis from their own essential oils (France) |
Essential oils used at home n/a Not reported here |
All 42 patients were sensitised to the oil they used, mainly lavender, tea tree (Melaleuca alternifolia) and ravintsara. 8 needed hospital care. 40% had not told their doctors they used essential oils, and only 33% had been given advice when they bought the oil. Niaouli is not named in the abstract. Methods, limits and fundingOutcomes: Which oils caused allergy; how oils were used Limitations: Patients already allergic, so no rate of allergy can be worked out. Not naming niaouli in an abstract is not proof niaouli is safe. Funding and conflicts: None declared. Read: abstract |
| Chao 2017 Melaleuca quinquenervia essential oil inhibits alpha-melanocyte-stimulating hormone-induced melanin production and oxidative stress in B16 melanoma cells. Phytomedicine · PMID 28899502 · DOI |
Laboratory study Melaleuca quinquenervia |
Mouse melanoma cells in a dish | M. quinquenervia essential oil and its main compounds Leaf (oil) Not reported here |
The oil was 1,8-cineole 21.60%, alpha-pinene 15.93%, viridiflorol 14.55% and alpha-terpineol 13.73%. In mouse melanoma cells, the oil and these compounds lowered melanin and tyrosinase activity and shifted antioxidant markers. The authors suggest the oil could be used as a skin-whitening agent. Methods, limits and fundingOutcomes: Melanin, tyrosinase activity and antioxidant markers Limitations: Mouse cancer cells in a dish. No skin or human test. The 'skin-whitening' idea is the authors' suggestion, not a finding. Funding and conflicts: None declared. Read: abstract |
| European Medicines Agency (EMA) 2016 Eucalypti aetheroleum: summary for the public EMA herbal medicine summary · Source |
Regulator/safety web page Eucalyptus (read-across) |
n/a | n/a n/a Not reported here |
The summary (first published and last updated 05/12/2016; a revised monograph is listed as 28/02/2025) says eucalyptus oil medicines are for traditional use for coughs and muscle pain, must not be given to children under 30 months because of a risk of laryngeal spasm (voice-box spasm), and must not be given to children with a history of seizures. Oral products are for ages 12 and up; inhaled, skin and bath products from age 4. No side effects had been reported when the committee assessed them. Methods, limits and fundingOutcomes: Safety, identity or regulatory statements Limitations: About eucalyptus oil, which is also rich in 1,8-cineole. It is NOT a niaouli statement. We apply it to niaouli only as a precaution, because both oils are cineole-rich. Read: full-text |
| Fikry 2025 Chemical Composition and Anti-Lung Cancer Activities of Melaleuca quinquenervia Leaf Essential Oil: Integrating GC/MS Profiling, Network Pharmacology, and Molecular Docking. Pharmaceuticals (Basel) · PMID 40573169 · DOI |
Laboratory and computer study Melaleuca quinquenervia |
Human cancer cell lines in a dish | M. quinquenervia leaf essential oil from Egypt Leaf (oil) Not reported here |
The oil was 1,8-cineole 31.57%, alpha-pinene isomers 21.26% and viridiflorol 13.65%. It was toxic to A549 lung cancer cells (IC50 18.09 micrograms per mL), slowed their movement and caused cell death in a dish. A computer analysis predicted targets that include ESR1, an oestrogen receptor gene. Methods, limits and fundingOutcomes: Cancer-cell killing, migration, cell cycle; predicted targets Limitations: Cells and computer modelling only. The authors call for animal work first. Killing cells in a dish does not mean a medicine, and healthy cells can be harmed too. Funding and conflicts: No conflict declared. Read: abstract |
| Fouyet 2022 Evaluation of Placental Toxicity of Five Essential Oils and Their Potential Endocrine-Disrupting Effects. Curr Issues Mol Biol · PMID 35877416 · DOI |
Laboratory study Human placental cells |
Human placental cells (JEG-Tox) in a dish | Niaouli, orange, tea tree, wintergreen and ylang-ylang oils and key compounds n/a Not reported here |
All five oils changed the release of at least one of four hormones, but none switched on the cell-death receptor tested. The authors call them hormone modulators rather than endocrine disruptors in these cells. Effects of the single compounds differed from the whole oils. Methods, limits and fundingOutcomes: Hormone release; P2X7 cell-death receptor Limitations: Cells in a dish. Does not show harm or safety in pregnancy. The authors are partly from an essential-oil company. Funding and conflicts: One author is an employee of Laboratoires Lea Nature; the others declare no conflict. Read: abstract |
| GBIF match 2026 Melaleuca quinquenervia (Cav.) S.T.Blake GBIF backbone · Source |
Taxonomy database Melaleuca quinquenervia |
n/a | n/a n/a Not reported here |
Read 2026-10-25: key 5415832, status ACCEPTED, family Myrtaceae, exact match. Methods, limits and fundingOutcomes: Safety, identity or regulatory statements Limitations: Name check only. Read: full-text |
| GBIF match 2026 Melaleuca viridiflora Sol. ex Gaertn. GBIF backbone · Source |
Taxonomy database Melaleuca viridiflora |
n/a | n/a n/a Not reported here |
Read 2026-10-25: key 5416109, status ACCEPTED, family Myrtaceae, exact match. Methods, limits and fundingOutcomes: Safety, identity or regulatory statements Limitations: Name check only. Read: full-text |
| Giraud-Robert A-M 2004 L'huile essentielle de niaouli (Melaleuca quinquenervia) dans la prevention des radiodermites du cancer du sein Phytotherapie 2(3) · Source |
Clinical report (details not read) human (reported) |
n/a | n/a n/a Not reported here |
A French-language clinical report on niaouli oil for skin burns from breast radiotherapy. Crossref confirms the title, author, journal and date (May 2004). We could not open the abstract or full text (the journal pages blocked us), so we do not know the number of women, the design, the method or the results from a source we read. Methods, limits and fundingOutcomes: Safety, identity or regulatory statements Limitations: Details NOT verified. A pharmacy web page that we could not open and a search summary mention about 20 women, which we treat as unconfirmed. No randomised controlled trial of niaouli for radiotherapy skin was found in PubMed. Not an independent trial result. Read: title-only |
| Halm 2014 Effect of an essential oil mixture on skin reactions in women undergoing radiotherapy for breast cancer: a pilot study. J Holist Nurs · PMID 24668063 · DOI |
Randomised pilot trial Essential oil mixture (not named) |
24 Women having radiotherapy for breast cancer |
An essential oil mixture (the abstract does not name the oils) n/a Not reported here |
24 women were randomised to the usual ointment (RadiaPlexRx) or an essential oil mixture, applied three times a day until 1 month after radiotherapy. No significant differences were found for skin reactions, quality of life or satisfaction. The authors concluded the mixture was not better than standard care and may be equivalent. Effect sizes 0.01 to 0.07 for skin (small to medium); no significant differences Methods, limits and fundingOutcomes: Skin reactions, quality of life and satisfaction Limitations: Very small. The abstract does not say the mixture contained niaouli, so it cannot be counted as a niaouli result. It is a pilot with no power to show a benefit or a harm. Funding and conflicts: None declared in the abstract. Read: abstract |
| Marche 1948 [Experimental and clinical data on gomenol (essence of Melaleuca viridiflora selected)]. J Med Chir Prat · PMID 18877504 |
Historical article (title only) n/a |
n/a | Gomenol (a French name for niaouli oil) n/a Not reported here |
No abstract in PubMed. The title shows a French medical article on gomenol, an essence of Melaleuca viridiflora, was published in 1948. Methods, limits and fundingOutcomes: n/a Limitations: Title only. We did not read the article, so we do not know what it found. Funding and conflicts: None stated. Read: abstract |
| Monti 2002 Effect of different terpene-containing essential oils on permeation of estradiol through hairless mouse skin. Int J Pharm · PMID 11955818 · DOI |
Laboratory study Mouse skin |
Hairless mouse skin in a dish | Six essential oils at 10% in propylene glycol, including niaouli n/a Not reported here |
Of cajuput, cardamom, melissa, myrtle, niaouli and orange oils, niaouli oil was the best at helping estradiol pass through mouse skin. The whole oil worked better than its main parts alone. Methods, limits and fundingOutcomes: How much estradiol passed through skin Limitations: Mouse skin in a dish, a drug-delivery question. It shows niaouli oil can change how other substances cross skin in a lab, not what happens in people. Funding and conflicts: None declared. Read: abstract |
| Monti 2009 Niaouli oils from different sources: analysis and influence on cutaneous permeation of estradiol in vitro. Drug Deliv · PMID 19538003 · DOI |
Laboratory study Mouse skin |
Four niaouli oils; hairless mouse skin | Niaouli essential oils from four sources n/a Not reported here |
All four oils had 1,8-cineole as the main part, but their make-up differed noticeably, and so did how much estradiol they helped through mouse skin. The authors note that niaouli oil's make-up depends on where it grows, the season and how it is distilled. Methods, limits and fundingOutcomes: Composition; estradiol passing through skin Limitations: Mouse skin in a dish. Shows that bottles differ, not that any is safe or unsafe. Funding and conflicts: None declared. Read: abstract |
| Nam 2008 Essential oil of niaouli preferentially potentiates antigen-specific cellular immunity and cytokine production by macrophages. Immunopharmacol Immunotoxicol · PMID 18668393 · DOI |
Animal study Mouse |
Mice given a test protein (KLH) | Niaouli essential oil given by injection into the abdomen (less than 500 microlitres per kg) n/a Not reported here |
In mice, injected niaouli oil raised some T-cell activity markers and signals from macrophages, but did not change antibody responses. The authors suggest a future use against infections. Methods, limits and fundingOutcomes: T-cell and macrophage immune markers Limitations: Mice, and the oil was injected into the abdomen, which is not how anyone uses the oil. No human data. Funding and conflicts: None declared. Read: abstract |
| National Center for Complementary and Integrative Health (NCCIH 2025 Tea tree oil NCCIH health page (updated April 2025) · Source |
Regulator/safety web page Melaleuca alternifolia (read-across) |
n/a | n/a n/a Not reported here |
Tea tree oil should not be swallowed; by mouth it can cause confusion, unsteadiness, inability to walk and coma. Skin products usually cause no problem but can cause redness or irritation, more likely if the oil is old or has been exposed to heat, light or air. Methods, limits and fundingOutcomes: Safety, identity or regulatory statements Limitations: About tea tree oil (Melaleuca alternifolia), a relative of niaouli. Not a niaouli statement. Read: full-text |
| Pet Poison Helpline Tea tree oil petpoisonhelpline.com page · Source |
Regulator/safety web page Melaleuca alternifolia (read-across) |
n/a | n/a n/a Not reported here |
Concentrated tea tree oil, on the skin or swallowed, can cause severe poisoning in pets even from a few drops. Signs include drooling, stomach upset, stumbling, weakness, tremors, coma, organ injury and low body temperature. Liver failure is named as a possible harm in cats. Pet shampoos with about 1 to 2% tea tree oil or less are generally considered non-toxic when used as labelled. Methods, limits and fundingOutcomes: Safety, identity or regulatory statements Limitations: About tea tree oil, not niaouli. The page does not mention diffusers. Read: full-text |
| Poison Control (US) Essential oils: Poisonous when misused poison.org article · Source |
Regulator/safety web page n/a |
n/a | n/a n/a Not reported here |
Swallowed essential oils can be poisonous, and breathing oil in while swallowing can cause pneumonia. Children's thin skin and immature livers may make them more vulnerable. Dilute pure oils in a carrier oil for skin use, and do not apply to damaged skin. The most common reaction is a skin rash; wash it off. Swallowed eucalyptus oil can cause seizures. Lock oils away from children and pets. Poison centre: 1-800-222-1222 (US). Methods, limits and fundingOutcomes: Safety, identity or regulatory statements Limitations: General advice, undated page, not niaouli-specific. It gives no dilution percentage. Read: full-text |
| PubChem (NCBI) 2026 PubChem compound records PubChem REST API · Source |
Chemistry database n/a |
n/a | n/a n/a Not reported here |
Read 2026-10-25: 1,8-cineole CID 2758 (C10H18O); viridiflorol CID 11996452 (C15H26O); nerolidol CID 5284507 (C15H26O); linalool CID 6549 (C10H18O); alpha-terpineol CID 17100 (C10H18O); alpha-pinene CID 6654 (C10H16); limonene CID 22311 (C10H16). Methods, limits and fundingOutcomes: Safety, identity or regulatory statements Limitations: Name and formula check only. Read: full-text |
| Sezener Kabay 2024 Antibacterial Effects of Essential Oils on P. aeruginosa, Methicillin-Resistant S. aureus, and Staphylococcus spp. Isolated from Dog Wounds. Pharmaceuticals (Basel) · PMID 39598405 · DOI |
Laboratory study Melaleuca quinquenervia (niaouli) |
44 Bacteria from infected dog wounds (44 isolates) and dog skin cells in a dish |
Niaouli, palmarosa and clove essential oils n/a Not reported here |
All three oils killed the bacteria tested in a dish (MBC/MIC 0.015 to 0.5 microlitres per mL). None reduced the bacteria's harmful enzymes. At 1000 micrograms per mL, dog skin cells stayed 96.39% alive with niaouli (75.4% palmarosa, 75.34% clove). The authors call the oils potential antibacterial agents for dogs. Methods, limits and fundingOutcomes: Germ-killing, biofilm and skin-cell survival Limitations: Dish work only; nothing was applied to a living animal. Skin-cell survival in a dish is not a pet-safety test. Funding and conflicts: One author is an employee of Art de Huile (a company); the authors declare no conflict of interest. Read: abstract |
| Shakeel 2021 Nanoemulsification Improves the Pharmaceutical Properties and Bioactivities of Niaouli Essential Oil (Melaleuca quinquenervia L.). Molecules · PMID 34443336 · DOI |
Laboratory study Melaleuca quinquenervia |
Skin bacteria in a dish; skin samples | Niaouli essential oil in lab-made nanoemulsions Leaf (oil) Not reported here |
All the nanoemulsion formulas slowed both skin bacteria in a dish. In skin samples (ex vivo), the nanoemulsions let more of the oil pass through than plain oil. No people were tested. Methods, limits and fundingOutcomes: Growth of Propionibacterium acnes and Staphylococcus epidermidis; skin permeation Limitations: Special lab formula (with added solvents and surfactants), not plain oil. Dish and skin-sample work only. Funding and conflicts: No conflict declared. Read: abstract |
| Theys 2023 Adaptive ecological knowledge among the Ndjuka Maroons of French Guiana; a case study of two 'invasive species': Melaleuca quinquenervia and Acacia mangium. J Ethnobiol Ethnomed · PMID 37434227 · DOI |
Interview study Melaleuca quinquenervia |
Ndjuka (Maroon) people in French Guiana | Niaouli tree (plant knowledge, not an oil trial) n/a Not reported here |
The community has taken niaouli into its medicinal plants, and uses, names and trades it, though the authors list it as an 'invasive alien' plant in the savannas of the region. Methods, limits and fundingOutcomes: Local use and knowledge of the tree Limitations: Ethnobotany. Shows how a community uses the tree, not whether any use works. Funding and conflicts: None declared. Read: abstract |
| U.S. Food and Drug Administration (FDA) Aromatherapy FDA cosmetics page · Source |
Regulator/safety web page n/a |
n/a | n/a n/a Not reported here |
FDA says aromatherapy products are regulated by their intended use. Products meant only to cleanse or smell pleasant are cosmetics (no approval before sale). Claims to treat or prevent disease, ease pain, treat anxiety or help sleep make a product a drug that needs approval. 'Natural' does not mean safe: plant ingredients can be toxic, irritating or allergenic. Methods, limits and fundingOutcomes: Safety, identity or regulatory statements Limitations: General page, not niaouli-specific. Undated. Read: full-text |
| Valarezo 2026 Chemical and Enantiomeric Profiling of Melaleuca viridiflora Sol. ex Gaertn. Essential Oil and Evaluation of Its Antimicrobial, Antioxidant, and Anticholinesterase Activities. Plants (Basel) · PMID 42884893 · DOI |
Laboratory and chemistry study Melaleuca viridiflora |
Lab (no people); oil from trees grown in the Americas | Niaouli leaf essential oil (M. viridiflora), steam distilled Leaf Not reported here |
Fifty compounds made up 99.07% of the oil. Main ones: 1,8-cineole 35.66%, viridiflorol 14.20%, limonene 11.04%, alpha-terpineol 7.89%, alpha-pinene 7.42%. Germ-killing effects needed a very high level (4000 micrograms per mL) and only worked on Listeria monocytogenes, Enterococcus faecium and the mould Aspergillus niger. Antioxidant action was weak. The oil blocked acetylcholinesterase at a moderate level (IC50 65.98 micrograms per mL) in a test tube. IC50 65.98 +/- 1.0 micrograms per mL (acetylcholinesterase, lab) Methods, limits and fundingOutcomes: Composition; germ-killing, antioxidant and enzyme tests Limitations: One oil sample from one region. Dish and test-tube work. Enzyme blocking is not a test of memory in people. Funding and conflicts: No conflict declared. Read: abstract |
| Vazquez 2023 HPTLC Analysis and Chemical Composition of Selected Melaleuca Essential Oils. Molecules · PMID 37175338 · DOI |
Chemistry study Melaleuca quinquenervia |
Melaleuca oils in a lab | Seven tea tree oils and four other Melaleuca oils, including two chemotypes of M. quinquenervia Leaf (oil) Not reported here |
Two M. quinquenervia oils were very different: one was mostly (E)-nerolidol (48.40%) and linalool (33.30%); the other was mostly 1,8-cineole (52.20%). Tea tree oils were mostly terpinen-4-ol. HPTLC fingerprints could tell the oils apart. Methods, limits and fundingOutcomes: Composition by GC-MS and HPTLC Limitations: Chemistry only. A very small number of samples. Funding and conflicts: Declared none; USDA-ARS authors. Read: abstract |
| Villar 1994 Toxicity of melaleuca oil and related essential oils applied topically on dogs and cats. Vet Hum Toxicol · PMID 8197716 |
Review of poison centre cases Dogs and cats |
Dogs and cats reported to a US animal poison centre | Melaleuca (tea tree) oil and related oils on the skin n/a Not reported here |
Vets reported poisoning when the oil was put on dogs or cats, mostly at inappropriately high amounts. Signs were depression, weakness, incoordination and muscle tremors. With treatment and supportive care the animals recovered without lasting harm within 2 to 3 days. Methods, limits and fundingOutcomes: Poisoning signs Limitations: About tea tree and related oils in general; niaouli is not named in the abstract. Old, and based on reported cases. Funding and conflicts: None declared. Read: abstract |
| Yasar 2026 Traditional and complementary medicine attitudes and practices of pregnant women for abnormal vaginal discharge. BMC Complement Med Ther · PMID 41877130 · DOI |
Online survey Human |
306 Pregnant women in Turkey |
Traditional methods; niaouli oil was the most used n/a Not reported here |
15% of the 306 women used traditional or complementary methods for vaginal discharge, and 57.1% of those used niaouli oil. The abstract does not say whether anyone was harmed or how the oil was used. Methods, limits and fundingOutcomes: Which traditional methods were used for vaginal discharge Limitations: A survey. Shows that some pregnant women use niaouli oil, not that it is safe or helps. Funding and conflicts: No competing interests declared. Read: abstract |
What we do not know yet
- What the evidence supports: every use is insufficient. There is no controlled human trial of niaouli oil.
- The 2004 French radiotherapy skin report could not be opened: size, design and results unverified.
- No niaouli-specific skin-sensitisation, poisoning, pregnancy, pet or interaction data.
- Child, seizure and pet cautions are read across from eucalyptus and tea tree.
- Tisserand, IFRA, RIFM, LiverTox and LactMed not read.
How new research is added
New studies are found by a saved PubMed search and are placed in a review queue. A person reads each one before it is added.
Lab markers
What changed in blood or saliva tests during trials. A changed number is not the same as feeling or being healthier, and we give no "normal ranges".
Other 4
Radiotherapy skin reaction (weekly clinical grading)
Unchanged vs standard ointment (pilot, oil mixture not named) in trials
A nurse or doctor's weekly score of redness, soreness and peeling on skin treated with radiation.
Not enough evidenceResults and what it means
Why it was measured
The main outcome in radiotherapy skin trials.
Statistical vs. clinical meaning
Shows only that one unnamed mixture was not clearly better than the usual ointment in a tiny trial.
Safety implication
A skin score does not show the oil is safe on irradiated skin.
| Study | Result | People | Product |
|---|---|---|---|
| 9 | No significant difference in skin reactions between an essential oil mixture and standard ointment; effect sizes 0.01 to 0.07. | 24 women, breast radiotherapy | Essential oil mixture (oils not named) |
Growth of acne bacteria in a dish
Lowered (in a dish) in trials
How far a test mixture slows the growth of Propionibacterium acnes and Staphylococcus epidermidis in a lab dish.
Not enough evidenceResults and what it means
Melanin and tyrosinase activity (cells)
Lowered (in a dish) in trials
How much pigment and pigment enzyme mouse melanoma cells make in a dish.
Not enough evidenceResults and what it means
Acetylcholinesterase activity (lab test)
Lowered (in a test tube) in trials
How strongly the oil blocks an enzyme that breaks down acetylcholine, a brain messenger.
Not enough evidenceResults and what it means
Safety
What studies and official sources say about side effects, medicines and who should check first. Each point shows what kind of evidence it comes from.
Main points to know 6
- Do not swallow essential oil.. Poison Control says swallowed essential oils can be poisonous, and breathing oil into the lungs while swallowing can cause pneumonia. NCCIH says swallowed tea tree oil, a close Melaleuca relative, has caused confusion, unsteadiness, inability to walk and coma. We found no niaouli poisoning report, and no safe amount for swallowing exists. This page gives no amount. Authoritative guidance 16 14
- Babies and young children: keep niaouli oil away from the face.. Niaouli oil is rich in 1,8-cineole (about 36% in one M. viridiflora oil; 21.6% to 52.2% in other M. quinquenervia oils). The EU medicines agency says eucalyptus oil medicines, which are also cineole-rich, must not be given to children under 30 months because of a risk of voice-box spasm, nor to children with a history of seizures. This is a read-across from eucalyptus. We found no niaouli-specific child statement, so the safe approach is to assume the same caution. Poison Control adds that children's thin skin and immature livers may make them more vulnerable. Authoritative guidance 3 22 2 23 16
- Skin: irritation and allergy are real, and old oil is worse. Do not use it undiluted.. Poison Control says the most common reaction to essential oils is a skin rash, that pure oils should be diluted in a carrier oil, and that they should not be used on damaged skin. NCCIH says old oil, or oil exposed to heat, light or air, is more likely to irritate (stated for tea tree oil). A French study of 42 people allergic to their own essential oils named lavender, tea tree and ravintsara; niaouli was not named in the abstract, which is not proof it is safe. We found no niaouli patch-test rate. This page gives no dilution figure. Authoritative guidance 16 14 1
- Radiotherapy skin: ask the radiotherapy team first.. Irradiated skin is damaged skin, and Poison Control says not to put essential oils on damaged skin. Niaouli oil's use for radiotherapy skin rests on a 2004 French report we could not read; no controlled trial was found. If you are having radiotherapy, ask the radiotherapy team before putting any oil on the treated area. Authoritative guidance 8 16 9
- Pregnancy and breastfeeding: not established.. No source we read says niaouli oil is safe in pregnancy. In human placental cells in a dish, niaouli oil changed the release of at least one hormone without triggering the cell-death receptor tested. A Turkish survey found niaouli oil was the most used traditional method among the 15% of 306 pregnant women who used one for vaginal discharge, with no harm data. Ask a doctor or midwife. Laboratory research 5 25
- Pets: keep oils and diffusers away from cats, dogs and birds.. Pet Poison Helpline says concentrated tea tree oil can cause severe poisoning in pets, even from a few drops on the skin, and names liver failure in cats. A veterinary report describes tremors and weakness in dogs and cats after melaleuca oil was put on their skin, with recovery in 2 to 3 days with treatment. Niaouli is not named in these sources, so the pet risk of niaouli itself is unknown. Authoritative guidance 15 24
Side effects 3
| Effect | How often | Severity and recovery | Evidence |
|---|---|---|---|
| Skin rash, irritation or allergic reaction General statements about essential oils. Niaouli was not named in the case-series abstract. | No rate found for niaouli oil | Mostly mild; 8 of 42 allergic patients in a French series needed hospital care (oils named: lavender, tea tree, ravintsara) Poison Control says to wash the oil off with soap and water; a persisting rash needs a doctor | Authoritative guidance 16 1 |
| Poisoning if swallowed (confusion, unsteadiness, seizures, coma, breathing the oil into the lungs) From poison-centre guidance on essential oils generally, eucalyptus oil (seizures) and tea tree oil (coma). | No niaouli case reports found | Can be serious Not described for niaouli | Authoritative guidance 16 14 |
| Voice-box spasm in very young children (cineole-rich oils) From the EMA statement on eucalyptus oil. Read-across, not a niaouli finding. | No niaouli reports found | Can be serious Not described | Authoritative guidance 3 |
Liver
No liver injury linked to niaouli oil was found. LiverTox was not searched for this oil. Pet Poison Helpline names liver failure in cats for concentrated tea tree oil, which is not a human finding. 15
How often. Not established.
Monitoring. Not applicable.
This is a safety connection. It is not evidence that Niaouli Oil supports liver health.
Medicines and supplements 3
| With | Why it matters | Importance | Evidence | What to do |
|---|---|---|---|---|
| Other skin products, including medicine patches and gels (for example hormone skin products) drug | In mouse skin in a dish, niaouli oil was the best of six oils at helping estradiol cross skin. | Unknown in people. Listed as a precaution only. | Laboratory research Not enough evidence 11 12 | If you use a medicine skin product, ask a pharmacist before putting niaouli oil on the same area. |
| Seizure medicines or a history of seizures condition | The EMA says eucalyptus oil medicines must not be given to children with a history of seizures, and Poison Control says swallowed eucalyptus oil can cause seizures. Niaouli is cineole-rich like eucalyptus. | Not shown for niaouli. A precaution carried over from a related oil. | Authoritative guidance Not enough evidence 3 16 | If you or your child has a seizure history, ask a doctor before using niaouli oil. |
| Blood thinners, other prescription medicines, supplements drug | No interaction study of niaouli oil with any medicine was found. | Unknown. | Not found Not enough evidence | Tell your pharmacist you use essential oils. |
Who should check first 3
| Situation | Advice | Evidence |
|---|---|---|
| Swallowing the oil (any person, child or pet) | Do not swallow essential oil. If it happens, contact a poison centre at once (US 1-800-222-1222) or your local emergency number. | Authoritative guidance 16 14 |
| Babies and children under about 30 months: on or near the face or nose | Do not use. The EMA's voice-box-spasm warning for cineole-rich eucalyptus oil is applied to niaouli as a precaution. | Authoritative guidance 3 |
| Undiluted oil on skin, or on broken, burned or irradiated skin | Do not. Poison Control says to dilute pure oils and not to use them on damaged skin. | Authoritative guidance 16 |
Overdose, product quality and regulators
Summary. No toxic or lethal amount for niaouli oil is given in the sources we read. Related oils (tea tree, eucalyptus) cause poisoning when swallowed.
Amounts. No safe amount is established, and this page gives none.
Onset and course. Not described for niaouli. For pets, signs from tea tree oil include drooling, stumbling, weakness and tremors.
Repeated use. Not studied for niaouli oil.
Animal data. A veterinary review describes poisoning of dogs and cats from melaleuca oil on skin, with recovery in 2 to 3 days. Mouse studies in this file were about benefits, not safety.
Toxic parts. The oil is steam-distilled from the leaves. It is a mixture rich in 1,8-cineole, with viridiflorol, limonene, alpha-terpineol and alpha-pinene in one analysis.
Not read. Tisserand and Young safety profile, RIFM and IFRA assessments, EU cosmetics rules, LiverTox and LactMed were not read. No niaouli-specific figure for sun sensitivity, asthma, cats or dogs was found.
What is in the bottle can differ from the label, and niaouli is known to vary a lot.
Two very different niaouli chemotypes. Two M. quinquenervia oils analysed in one paper were chemically very different: one was mostly (E)-nerolidol (48.40%) and linalool (33.30%), the other mostly 1,8-cineole (52.20%). Safety statements for a cineole-rich oil may not fit a nerolidol-rich one. 23
Source, season and distillation. Four niaouli oils from different sources all had 1,8-cineole as the main part but differed noticeably. The authors say makeup depends on growing place, season and extraction process. 12
Two species under one name. Papers use niaouli for both M. quinquenervia and M. viridiflora. GBIF lists both as accepted names. 6 7
Old or air-exposed oil. NCCIH says aged or air-exposed tea tree oil is more likely to irritate skin. No niaouli-specific data was found. 14
Adulteration and label accuracy. We found no study of how often niaouli oil is adulterated. Poison Control says essential oil products are not well regulated. 16
| Body | Action | Date |
|---|---|---|
| EMA (European Medicines Agency) - eucalyptus oil (EU) | Traditional use only for coughs and muscle pain; not for children under 30 months or with seizure history. About eucalyptus, not niaouli. source | 2016-12-05 (summary); revised monograph listed 2025-02-28 |
| FDA - aromatherapy (US) | Regulated by intended use: cosmetic or drug. Treatment claims make a product a drug needing approval. source | not stated |
| NCCIH - tea tree oil (US) | Do not swallow tea tree oil. A relative of niaouli, not niaouli itself. source | April 2025 |
When to get medical help
- If a child or pet may have swallowed any essential oil, call a poison centre (US 1-800-222-1222) or your local emergency number at once. Do not wait for signs.
- Call emergency services for any breathing difficulty, swelling of the face or throat, or collapse after exposure to an essential oil.
- Seizures, confusion, unsteadiness or unusual drowsiness after swallowing or heavy exposure need emergency care.
- A spreading, blistering or weeping rash: stop using the oil, wash with soap and water and see a doctor.
Stop using the product and contact a clinician or emergency service. In the US, Poison Control is 1-800-222-1222.
General information only, not medical advice. Ask a clinician or pharmacist before use, especially with medicines, in pregnancy or with a health condition. See the Natural Remedy Safety guide.
Frequently asked questions
Is niaouli oil safe to swallow?
No. Do not swallow essential oil. Poison Control warns swallowed oils can be poisonous, and NCCIH reports confusion and coma from swallowed tea tree oil, a relative. We found no niaouli cases and no safe amount. If a child or pet may have swallowed any essential oil, call a poison centre (US 1-800-222-1222) or your emergency number.
Is niaouli oil safe for babies and young children?
Keep it away from their faces and noses. The EU medicines agency bars cineole-rich eucalyptus oil medicines for children under 30 months because of voice-box spasm, and for children with seizures. Niaouli is also cineole-rich, but no niaouli-specific statement was found, so treat the caution as applying. Ask a paediatrician or pharmacist.
Can niaouli oil cause skin reactions?
Does niaouli oil protect skin during radiotherapy?
Is niaouli oil safe in pregnancy?
Is niaouli oil safe around pets?
Does niaouli oil help with colds or a blocked nose?
No controlled trial of niaouli oil was found. It is cineole-rich like eucalyptus, which the EU accepts for coughs only on traditional use. That does not carry over to niaouli.
Does niaouli oil treat acne?
Not shown. A special lab nanoemulsion slowed two skin bacteria in a dish, but nobody tested it on acne in people.
Can niaouli oil treat cancer?
No. The leaf oil killed lung cancer cells in a dish, which says nothing about treatment, and an oil that kills cells in a dish may harm healthy cells too.
Is niaouli oil the same as tea tree or eucalyptus oil?
Are all niaouli oils the same?
Can I trust the label on a bottle?
Not automatically. Poison Control says essential oil products are not well regulated. We found no study of how often niaouli oil is adulterated, so check that a label gives the Latin name and plant part.
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Editorial transparency
- Written by
- AlternativeMed editorial team. Research compiled with AI assistance, then checked against PubMed records.
- Medical review
- None. This page has not been reviewed by a physician or pharmacist.
- First published
- 2026-10-25
- Last substantive update
- 2026-10-25
- How we research
- We read the abstracts of 15 PubMed papers (a 1948 French article is title only), confirmed a 2004 French article's record through Crossref (text not read), read the EMA, Poison Control, NCCIH, Pet Poison Helpline and FDA pages, checked both tree names in GBIF and seven compounds in PubChem.
- How we rate evidence
- See "How we rate evidence" in the Evidence tab.
- Independence
- No product is promoted on this page. No affiliate links are shown. Industry links are labelled where authors declared them.
Sources 25
Each source was opened and checked. Where we read only the abstract, it says so. The small numbers in the text point here.
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- Chao WW, Su CC, Peng HY, Chou ST. Melaleuca quinquenervia essential oil inhibits alpha-melanocyte-stimulating hormone-induced melanin production and oxidative stress in B16 melanoma cells.. Phytomedicine. 2017. PMID 28899502. DOI 10.1016/j.phymed.2017.08.024. (abstract)
- European Medicines Agency (EMA). Eucalypti aetheroleum: summary for the public. EMA herbal medicine summary. 2016. (full-text)
- Fikry E, Orfali R, Perveen S, Ghaffar S, et al. Chemical Composition and Anti-Lung Cancer Activities of Melaleuca quinquenervia Leaf Essential Oil: Integrating GC/MS Profiling, Network Pharmacology, and Molecular Docking.. Pharmaceuticals (Basel). 2025. PMID 40573169. DOI 10.3390/ph18060771. (abstract)
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- GBIF match API. Melaleuca quinquenervia (Cav.) S.T.Blake. GBIF backbone. 2026. (full-text)
- GBIF match API. Melaleuca viridiflora Sol. ex Gaertn.. GBIF backbone. 2026. (full-text)
- Giraud-Robert A-M. L'huile essentielle de niaouli (Melaleuca quinquenervia) dans la prevention des radiodermites du cancer du sein. Phytotherapie 2(3). 2004. (title-only)
- Halm MA, Baker C, Harshe V. Effect of an essential oil mixture on skin reactions in women undergoing radiotherapy for breast cancer: a pilot study.. J Holist Nurs. 2014. PMID 24668063. DOI 10.1177/0898010114527184. (abstract)
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- National Center for Complementary and Integrative Health (NCCIH, US). Tea tree oil. NCCIH health page (updated April 2025). 2025. (full-text)
- Pet Poison Helpline. Tea tree oil. petpoisonhelpline.com page. . (full-text)
- Poison Control (US). Essential oils: Poisonous when misused. poison.org article. . (full-text)
- PubChem (NCBI). PubChem compound records. PubChem REST API. 2026. (full-text)
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- Theys J, Tareau MA, Ansoe-Tareau C, Greene A, et al. Adaptive ecological knowledge among the Ndjuka Maroons of French Guiana; a case study of two 'invasive species': Melaleuca quinquenervia and Acacia mangium.. J Ethnobiol Ethnomed. 2023. PMID 37434227. DOI 10.1186/s13002-023-00602-7. (abstract)
- U.S. Food and Drug Administration (FDA). Aromatherapy. FDA cosmetics page. . (full-text)
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- Yasar O, Kalipcioglu H. Traditional and complementary medicine attitudes and practices of pregnant women for abnormal vaginal discharge.. BMC Complement Med Ther. 2026. PMID 41877130. DOI 10.1186/s12906-026-05355-w. (abstract)