Safety Profile
Known Safety Concerns
- TOXIC if ingested — CNS depression, loss of consciousness; CONTRAINDICATED orally; contact dermatitis topically; not for infants; endocrine disruption concern at high doses
Contraindications
- TOXIC if ingested — CNS depression, loss of consciousness; CONTRAINDICATED orally; contact dermatitis topically; not for infants; endocrine disruption concern at high doses
Interactions
Information not yet available for this ingredient profile.
Evidence and Scientific Findings
Ingredient Overview
Tea Tree Oil (TTO) is an essential oil steam-distilled from Melaleuca alternifolia leaves, native to Australia. Primary active constituents: terpinen-4-ol (the main antimicrobial component; typically 30–48%), gamma-terpinene, alpha-terpinene, 1,8-cineole (eucalyptol), and para-cymene. TTO has well-established broad-spectrum antimicrobial activity against bacteria (Staphylococcus aureus including MRSA, Escherichia coli), fungi (Candida albicans, dermatophytes), and some viruses — documented in multiple in vitro and some clinical studies. Topical clinical evidence: acne (comparable to 5% benzoyl peroxide with fewer side effects), tinea pedis (athlete’s foot), onychomycosis (nail fungus), seborrhoeic dermatitis. CRITICAL SAFETY — ORAL TOXICITY: Tea Tree Oil is TOXIC when ingested. Documented cases of serious adverse events following oral ingestion include: CNS depression, loss of consciousness, ataxia (incoordination), muscle weakness, confusion, rash, blood cell abnormalities. CONTRAINDICATED for internal/oral use in any form. Products marketed for oral consumption containing undiluted TTO constitute a significant safety risk. Topical use: should be diluted (0.5–5% concentration); neat application can cause contact dermatitis, skin irritation, and sensitisation. Allergic contact dermatitis from limonene, alpha-terpinene, and aromadendrene oxidation products (TTO oxidises on storage — use fresh, store in dark airtight container). Cases of hormonal disruption reported at high topical doses (lavender and TTO weak endocrine activity — gynecomastia case reports). Avoid near eyes. NOT for use in infants under 2 years. NOT for internal use at any age.
Biological and Chemical Classification
- Scientific Name
- Melaleuca alternifolia
Mechanism of Action
Information not yet available for this ingredient profile.
Clinical Evidence of Effectiveness
Information not yet available for this ingredient profile.
Pharmacokinetics
Information not yet available for this ingredient profile.
Recommended Dosage
Information not yet available for this ingredient profile.
SETI — Scientific Evidence Transparency Index
Executive Summary — Ingredient Assessment
- 10 studies reviewed
- 0 high-quality studies (meta-analysis or RCT)
- Main clinical benefit observed: Botanical
- Evidence consistency: High consistency across studies (100%)
- TOXIC if ingested — CNS depression, loss of consciousness; CONTRAINDICATED orally; contact dermatitis topically; not for infants; endocrine disruption concern at high doses
The available scientific evidence for Tea Tree Oil indicates notable safety signals that warrant caution. Use should be considered carefully and monitored, particularly in sensitive populations or alongside other medications.
Total SETI Score
High risk| Evidence quality | 10/40 |
| Evidence consistency | 20/20 |
| Safety signals | 0/20 |
| Study recency | 10/10 |
| Evidence transparency | 10/10 |
Evidence Summary
- 10 studies reviewed
- 0 high-quality studies (meta-analysis or systematic review)
- 0 studies identified benefits or no safety concern (GREEN)
- 10 studies reported limited or advisory safety evidence (YELLOW)
Evidence Policy
Only peer-reviewed scientific literature indexed in PubMed or comparable databases is included in this evaluation. Commercial websites, blogs, and marketing materials are excluded. All references include direct traceable links to source documents.
Last updated: 06 აპრ 2026, 12:08
Evidence Distribution
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Observational / other LOW evidence YELLOWIn vitro and in silico validation of the therapeutic potential of Tea tree (Melaleuca alternifolia) oil through GC/MS integrated profiling, and molecular… ↗Sankaranarayanan P et al.. In vitro and in silico validation of the therapeutic potential of Tea tree (Melaleuca alternifolia) oil through GC/MS integrated profiling, and molecular dynamic simulation.. In Silico Pharmacol. 2026. PMID:41930245.PMID 41930245 ↗Journal In Silico PharmacolYear 2026Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/41930245/
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Observational / other LOW evidence YELLOWChemical composition and phytotoxicity of Eucalyptus parvula (Hill & Johnson) and Melaleuca alternifolia (Cheel) essential oils grown in Tuscany, Italy. ↗Clemente C et al.. Chemical composition and phytotoxicity of Eucalyptus parvula (Hill & Johnson) and Melaleuca alternifolia (Cheel) essential oils grown in Tuscany, Italy.. Front Plant Sci. 2026. PMID:41919038.PMID 41919038 ↗Journal Front Plant SciYear 2026Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/41919038/
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Observational / other LOW evidence YELLOWPhytomedicines and conventional drugs in scabies management. ↗Hoque M. Phytomedicines and conventional drugs in scabies management.. GMS Hyg Infect Control. 2026. PMID:41835968.PMID 41835968 ↗Journal GMS Hyg Infect ControlYear 2026Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/41835968/
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Observational / other LOW evidence YELLOWMedicinal Chemistry of Natural Anti-Skin Cancer Agents: An Evidence-Based Literature Review. ↗Al-Hasan M et al.. Medicinal Chemistry of Natural Anti-Skin Cancer Agents: An Evidence-Based Literature Review.. Anticancer Agents Med Chem. 2026. PMID:41833027.PMID 41833027 ↗Journal Anticancer Agents Med ChemYear 2026Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/41833027/
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Observational / other LOW evidence YELLOWBactericidal and anti-virulence effects of Melaleuca alternifolia essential oil against foodborne pathogens: in vitro and milk matrix assay. ↗Magna LR et al.. Bactericidal and anti-virulence effects of Melaleuca alternifolia essential oil against foodborne pathogens: in vitro and milk matrix assay.. Lett Appl Microbiol. 2026. PMID:41733458.PMID 41733458 ↗Journal Lett Appl MicrobiolYear 2026Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/41733458/
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Observational / other LOW evidence YELLOWPhytochemistry and pharmacology of Melaleuca alternifolia: Bridging aboriginal heritage with contemporary science. ↗Ebrahimi N et al.. Phytochemistry and pharmacology of Melaleuca alternifolia: Bridging aboriginal heritage with contemporary science.. Biochim Biophys Acta Gen Subj. 2026. PMID:41679395.PMID 41679395 ↗Journal Biochim Biophys Acta Gen SubjYear 2026Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/41679395/
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Observational / other LOW evidence YELLOWPhysiological quality of Arabica coffee seeds treated with essential oils. ↗Coelho APF et al.. Physiological quality of Arabica coffee seeds treated with essential oils.. Braz J Biol. 2026. PMID:41637271.PMID 41637271 ↗Journal Braz J BiolYear 2026Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/41637271/
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Observational / other LOW evidence YELLOWBiosynthesis of silver nanoparticles via Melaleuca alternifolia leaf extract for antibacterial, antifungal, antioxidant and anticancer activity. ↗Dayana BM et al.. Biosynthesis of silver nanoparticles via Melaleuca alternifolia leaf extract for antibacterial, antifungal, antioxidant and anticancer activity.. Sci Rep. 2026. PMID:41559132.PMID 41559132 ↗Journal Sci RepYear 2026Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/41559132/
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Observational / other LOW evidence YELLOWAssessing anti-plaque efficiency of a herbal dentifrice. ↗Ghosh D et al.. Assessing anti-plaque efficiency of a herbal dentifrice.. Bioinformation. 2025. PMID:41623768.PMID 41623768 ↗Journal BioinformationYear 2025Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/41623768/
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Observational / other LOW evidence YELLOWApplication of chitosan-based nanomatrix enriched with Melaleuca alternifolia essential oil against the growth of storage fungi and aflatoxin B(1) contamination in maize… ↗Vivekanand et al.. Application of chitosan-based nanomatrix enriched with Melaleuca alternifolia essential oil against the growth of storage fungi and aflatoxin B(1) contamination in maize seeds.. Braz J Microbiol. 2025. PMID:41405762.PMID 41405762 ↗Journal Braz J MicrobiolYear 2025Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/41405762/
Score Transparency
0 of 10 approved references (score saturates at 10). More peer-reviewed studies = stronger evidence base.
Method: Q = number of approved references ÷ 10 (capped at 1.0)
Limited — mostly case reports or animal studies
Method: L = mean study-level weight across approved references. Level 1 (meta-analysis / systematic review) = 1.0; Level 2 (RCT) = 0.8; Level 3 (cohort/case-control) = 0.6; Level 4 (case report) = 0.4; Level 5 (animal / in-vitro) = 0.2.
Mixed or neutral — roughly equal benefit and risk signals
Method: D = (sum of risk-scored references − sum of benefit-scored references) ÷ total evidence score, then scaled from [−1, 1] to [0, 1]. 0.0 = pure benefit; 0.5 = neutral; 1.0 = pure risk.
One or more monitoring-level safety signals active
Method: S = 0.5 (neutral baseline) + sum of active signal severity deltas ÷ 10. Severity deltas: Critical = +2.0, High = +1.5, Moderate = +1.0, Low = +0.5. Capped at 1.0.
Final GIRI Score for Tea Tree Oil. Risk level thresholds: Low 0–3.0 · Moderate 3.0–5.5 · High 5.5–7.5 · Critical 7.5–10.
Full methodology & data sources
The GIRI Score is computed entirely from structured data — no editorial scoring or subjective weighting is applied at any step.
- References: Only approved references are counted. Each reference is assigned an evidence level (L1–L5) and a direction (risk / neutral / benefit) by the reference manager or AI classifier.
- Safety Signals: Sourced from regulatory agencies (FDA, EMA, Health Canada, TGA, and others) and pharmacovigilance databases. Only active signals count toward the score.
- Formula version: GIRI Score v3.7.0 — Q × L × D × S × 10.
- Limitations: The score reflects published evidence and recorded signals as of the last update date. It is not a clinical risk assessment and should not replace advice from a qualified healthcare professional.
Risk Level Classification
Based on available regulatory signals and scientific evidence, this ingredient presents a high safety concern. Its use in dietary supplements is associated with documented adverse events.
0–3.0
3.0–5.5
5.5–7.5
7.5–10
The score pin shows exactly where this ingredient falls on the fixed risk scale.
What drove the High classification for Tea Tree Oil
A score of 7.0 places this ingredient in the High band. Thresholds: Low 0–3.0 · Moderate 3.0–5.5 · High 5.5–7.5 · Critical 7.5–10.
0 approved references.
Limited — mostly case reports or animal studies (Level 4–5).
Neutral or mixed — benefit and risk signals roughly balanced.
No active signals — S component is at neutral baseline (0.5), contributing no extra risk weight.
No major regulatory restrictions or advisories recorded across monitored jurisdictions (FDA, EMA, Health Canada, TGA, and others).
How are the Low / Moderate / High / Critical thresholds defined?
The four risk levels are fixed score bands. A score is assigned to exactly one level based on where it falls:
| Level | Score | Meaning |
|---|---|---|
| LOW | 0.0 – 2.9 | Sparse or predominantly beneficial evidence. No active safety alerts. |
| MODERATE | 3.0 – 5.4 | Mixed signals — some risk alongside benefit. Caution at high doses or in sensitive groups. |
| HIGH | 5.5 – 7.4 | Multiple studies or regulatory alerts documenting adverse effects. Professional oversight recommended. |
| CRITICAL | 7.5 – 10 | Regulatory restrictions in one or more major jurisdictions. Serious documented harm. Avoid without specialist supervision. |
Thresholds are fixed constants (GIRI_Score_Utils::LEVEL_THRESHOLDS). They do not change per ingredient and are never subject to editorial adjustment.