Butylated hydroxytoluene (BHT) on your skin: a safety profile
Low riskNot medical or professional safety advice, and not a substitute for a qualified clinician — consult one. Full disclaimer →
Cosmetic and personal-care-product topical contact; documented contact-dermatitis sensitisation in formulator and consumer cohorts but rare at consumer concentrations.
What is butylated hydroxytoluene (bht)?
The IUPAC name is 2,6-ditert-butyl-4-methylphenol.
Also known as: 2,6-ditert-butyl-4-methylphenol, 2,6-Di-tert-butyl-4-methylphenol, 2,6-Di-tert-butyl-p-cresol, Butylhydroxytoluene.
- IUPAC name
- 2,6-ditert-butyl-4-methylphenol
- CAS number
- 128-37-0
- Molecular formula
- C15H24O
- Molecular weight
- 220.35 g/mol
- SMILES
- CC1=CC(=C(C(=C1)C(C)(C)C)O)C(C)(C)C
- PubChem CID
- 31404
Risk for people
Low riskCosmetic and personal-care-product topical contact; documented contact-dermatitis sensitisation in formulator and consumer cohorts but rare at consumer concentrations.
Regulatory consensus
11 regulatory and scientific bodies have classified Butylated hydroxytoluene (BHT). The classifications differ — that's the data.
| Agency | Year | Classification | Notes |
|---|---|---|---|
| IARC | — | Group 3 | |
| EPA CTX / IARC | — | Group 3 - Not classifiable as to its carcinogenicity to humans | |
| EPA CTX / Genetox | — | Genotoxicity: positive (Ames: positive, 83 positive / 15 negative reports) | |
| EPA CTX / Genetox | — | Genotoxicity: positive (Ames: positive, 83 positive / 15 negative reports) | |
| EPA CTX / Skin-Eye | — | Skin Irritation: SkinIrr2 (score: high) | |
| EPA CTX / Skin-Eye | — | Eye Irritation: Category 2B (score: moderate) | |
| EPA CTX / Skin-Eye | — | Skin Irritation: Not classified (score: low) | |
| EPA CTX / Skin-Eye | — | Skin Sensitization: Category 6.5B (Category 1) (score: moderate) | |
| EPA CTX / Skin-Eye | — | skin sensitisation: in vivo (non-LLNA): Not likely to be sensitizing (score: low) | |
| EPA CTX / Skin-Eye | — | eye irritation: in vivo: Studies Indicate No Significant Irritation (score: low) | |
| EPA CTX / Skin-Eye | — | skin irritation: in vivo: Studies Indicate No Significant Irritation (score: low) |
Regulators apply different standards of evidence — animal-data weighting, exposure-pattern assumptions, epidemiological power thresholds — which is why two scientific bodies can review the same data and reach different conclusions. The disagreement is the data.
Where you encounter butylated hydroxytoluene (bht)
- Industrial Facilities — Manufacturing plants, Chemical storage areas, Waste treatment sites
- Occupational Environments — Factories, Warehouses, Transportation vehicles
- Personal Care — shampoo, conditioner, lotion, cosmetics, sunscreen
Safer alternatives
Lower-risk approaches that achieve a similar outcome to Butylated hydroxytoluene (BHT):
-
Fragrance-free formulations
Trade-offs: Consumer preference for scented productsRelative cost: Lower (ingredient elimination)
-
Essential oil-based fragrances (with disclosure)
Trade-offs: Natural does not mean safe — many essential oils are skin sensitizersRelative cost: 2-5× conventional
Frequently asked questions
Is butylated hydroxytoluene (bht) safe for you?
Cosmetic and personal-care-product topical contact; documented contact-dermatitis sensitisation in formulator and consumer cohorts but rare at consumer concentrations.
What products contain butylated hydroxytoluene (bht)?
Butylated hydroxytoluene (BHT) appears in: Manufacturing plants (Industrial facilities); Chemical storage areas (Industrial facilities); Factories (Occupational environments); Warehouses (Occupational environments); shampoo (Personal care).
Why do regulators disagree about butylated hydroxytoluene (bht)?
Butylated hydroxytoluene (BHT) has been classified by 11 agencies including IARC, EPA CTX / IARC, EPA CTX / Genetox, EPA CTX / Genetox, EPA CTX / Skin-Eye, with differing conclusions. Regulators apply different standards of evidence (animal data weighting, exposure-pattern assumptions, epidemiological power thresholds), which is why two scientific bodies can review the same data and reach different conclusions. See the regulatory consensus table on this page for the full picture.
See Butylated hydroxytoluene (BHT) in the body app
Look up products containing butylated hydroxytoluene (bht), compare to alternatives, and explore the full data record.
Open in body View raw API dataSources (2)
- IARC Monographs Volume 40: Some Naturally Occurring and Synthetic Food Components — BHT Group 3 Evaluation (Not Classifiable as to Carcinogenicity) (1986) — regulatory
- US FDA: Butylated Hydroxytoluene (BHT) — GRAS Affirmation, Acceptable Daily Intake, and Food Additive Regulations (21 CFR 172.115) (2020) — regulatory
Reference data, not professional advice. Aggregates publicly available regulatory and scientific data; not a substitute for medical, legal, or regulatory advice. Why we built ALETHEIA →