Baby Safety / Compounds / Thymol

Is Thymol safe for babies and kids?

Elevated risk for kids

Infants are more vulnerable to Thymol than children or adults due to immature hepatic/renal clearance, higher intake-to-body-weight ratio, rapid organ development, and increased gastrointestinal absorption.

What is thymol?

The IUPAC name is 5-methyl-2-propan-2-ylphenol.

Also known as: 5-methyl-2-propan-2-ylphenol, 2-Isopropyl-5-methylphenol, Thyme camphor, 5-Methyl-2-(1-methylethyl)phenol.

IUPAC name
5-methyl-2-propan-2-ylphenol
CAS number
89-83-8
Molecular formula
C10H14O
Molecular weight
150.22 g/mol
SMILES
CC1=CC(=C(C=C1)C(C)C)O
PubChem CID
6989

Risk for babies

Elevated risk

Infants are more vulnerable to Thymol than children or adults due to immature hepatic/renal clearance, higher intake-to-body-weight ratio, rapid organ development, and increased gastrointestinal absorption.

Neonates and infants up to 12 months have incomplete blood-brain barrier development, immature Phase I/II metabolic enzymes (particularly CYP3A4, UGT1A1), and higher gastrointestinal permeability. Equivalent doses produce higher internal concentrations and longer residence times.

What to do: Minimize infant exposure through source control. For breastfeeding mothers: reduce maternal exposure. For formula-fed infants: use certified low-migration bottles and verified water sources. Consult pediatrician regarding any concerns.

Risk for pregnant and nursing people

Context-dependent

Prenatal exposure to Thymol through personal care products may affect fetal development. Some fragrance chemicals are sensitizers or endocrine-active compounds with transplacental transfer.

No specific reproductive toxicity data identified, but pregnancy-specific safety data is limited for most chemicals. Precautionary minimization of exposure is recommended.

What to do: Minimize exposure during pregnancy and lactation. Consult healthcare provider regarding specific risks. Consider alternative products with lower hazard profiles.

Regulatory consensus

2 regulatory and scientific bodies have classified Thymol. The classifications differ — that's the data.

AgencyYearClassificationNotes
FDA1965GRASGRAS food flavoring — thyme component
US_EPA2024registered_antimicrobialEPA-registered antimicrobial ingredient (biopesticide)

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 kids encounter thymol

  • Personal Care — essential oils, oral care, antiseptics
  • Food — spice flavoring (thymol, carvacrol)
  • Fragrance — perfume, cologne, scented personal care products, household fragrance products, candles
    Identified in Fragrance Ingredient Safety Priority Research database (2,325 ingredients)

Safer alternatives

Lower-risk approaches that achieve a similar outcome to Thymol:

  • Menthol (for oral care)
    Trade-offs: Alternative fragrance ingredient; individual safety profile should be assessed per IFRA standards; sensitization potential varies by compound; patch testing recommended for sensitive individuals.
    Relative cost: 1.2-2×
  • Cetylpyridinium chloride (mouthwash)
    Trade-offs: Alternative fragrance ingredient; individual safety profile should be assessed per IFRA standards; sensitization potential varies by compound; patch testing recommended for sensitive individuals.
    Relative cost: 1.2-2×

Frequently asked questions

Is thymol safe for kids?

Infants are more vulnerable to Thymol than children or adults due to immature hepatic/renal clearance, higher intake-to-body-weight ratio, rapid organ development, and increased gastrointestinal absorption.

What products contain thymol?

Thymol appears in: essential oils (Personal care); oral care (Personal care); spice flavoring (thymol, carvacrol) (Food); perfume (Fragrance); cologne (Fragrance).

What should I do if my child is exposed to thymol?

Minimize infant exposure through source control. For breastfeeding mothers: reduce maternal exposure. For formula-fed infants: use certified low-migration bottles and verified water sources. Consult pediatrician regarding any concerns.

See Thymol in the baby app

Look up products containing thymol, compare to alternatives, and explore the full data record.

Open in baby View raw API data

Sources (1)
  1. PubChem Compound Database (2026) — database

Reference data, not professional advice. Aggregates publicly available regulatory and scientific data; not a substitute for veterinary, medical, legal, or regulatory advice. Why we built ALETHEIA →