Baby Safety / Compounds / Naphthalene

Is Naphthalene safe for babies and kids?

Context-dependent for kids

(Babies-specific data is limited; this page draws from human pregnant context.) Pregnancy alters the metabolism and distribution of Naphthalene, potentially increasing fetal exposure. The developing embryo/fetus is vulnerable during organogenesis (weeks 3-8) and neurological development. Placental transfer should be assumed.

What is naphthalene?

Also known as: Naphthalin, Tar camphor, White tar, Albocarbon.

IUPAC name
naphthalene
CAS number
91-20-3
Molecular formula
C10H8
Molecular weight
128.17 g/mol
SMILES
C1=CC=C2C=CC=CC2=C1
PubChem CID
931

Risk for babies

Context-dependent

Pregnancy alters the metabolism and distribution of Naphthalene, potentially increasing fetal exposure. The developing embryo/fetus is vulnerable during organogenesis (weeks 3-8) and neurological development. Placental transfer should be assumed.

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.

Risk for pregnant and nursing people

Context-dependent

Pregnancy alters the metabolism and distribution of Naphthalene, potentially increasing fetal exposure. The developing embryo/fetus is vulnerable during organogenesis (weeks 3-8) and neurological development. Placental transfer should be assumed.

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

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

AgencyYearClassificationNotes
IARC2002Group 2B (possibly carcinogenic to humans)IARC Monograph 82 (2002). Sufficient evidence in animals (Clara cell and alveolar/bronchiolar adenomas in mice at high doses; olfactory epithelium tumors in rats); limited evidence in humans. Primary concern is inhalation of naphthalene vapors from mothballs, which are practically pure naphthalene. Naphthalene is metabolized to naphthalene 1,2-oxide and then to 1-naphthol, 2-naphthol, and naphthalene dihydrodiol — some metabolites are genotoxic. Human carcinogenicity data are limited and insufficient for higher classification; the 2B classification reflects primarily the animal evidence at high inhalation exposures. Not to be confused with paradichlorobenzene mothballs (a separate compound).
US EPA1998Possible human carcinogen (Group C)US EPA IRIS assessment (1998). Naphthalene classified as a possible human carcinogen based on limited human evidence and sufficient animal evidence of carcinogenicity. EPA inhalation unit risk: 3.4 × 10⁻⁵ per μg/m³. EPA oral slope factor: 0.12/mg/kg-day. Primary regulatory concern is occupational and residential inhalation of naphthalene vapors from mothball use and combustion (coal tar, vehicle exhaust, cigarette smoke). Naphthalene is also an EPA priority HAP (hazardous air pollutant).
EPA CTX / IRISC (Possible human carcinogen)
EPA CTX / IRISCarcinogenic potential cannot be determined
EPA CTX / NTP RoCReasonably Anticipated to be a Human Carcinogen
EPA CTX / IARCGroup 2B - Possibly carcinogenic to humans
EPA CTX / Health CanadaGroup C: IRIS (a possible human carcinogen)
EPA CTX / CalEPAKnown human carcinogen
EPA CTX / GenetoxGenotoxicity: negative (Ames: negative, 0 positive / 12 negative reports)
EPA CTX / GenetoxGenotoxicity: negative (Ames: negative, 0 positive / 12 negative reports)
EPA CTX / Skin-EyeEye Irritation: Category 2B (score: moderate)
EPA CTX / Skin-EyeSkin Irritation: Not classified (score: low)
EPA CTX / Skin-EyeSkin Sensitization: Category 1 (score: high)
EPA CTX / Skin-EyeEye Irritation: Category 6.4A (Category 2A) (score: high)
EPA CTX / Skin-EyeSkin Irritation: Category 6.3B (Category 3) (score: moderate)
EPA CTX / Skin-Eyeskin sensitisation: in vivo (non-LLNA): Not likely to be sensitizing (score: low)
EPA CTX / Skin-Eyeeye irritation: in vivo: Studies Indicate No Significant Irritation (score: low)
EPA CTX / Skin-Eyeskin 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 kids encounter naphthalene

  • Industrial FacilitiesManufacturing plants, Chemical storage areas, Waste treatment sites
  • Occupational EnvironmentsFactories, Warehouses, Transportation vehicles

Safer alternatives

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

  • Fragrance-free formulations
    Trade-offs: Consumer preference for scented products
    Relative cost: Lower (ingredient elimination)
  • Essential oil-based fragrances (with disclosure)
    Trade-offs: Natural does not mean safe — many essential oils are skin sensitizers
    Relative cost: 2-5× conventional

Frequently asked questions

What products contain naphthalene?

Naphthalene appears in: Manufacturing plants (Industrial facilities); Chemical storage areas (Industrial facilities); Factories (Occupational environments); Warehouses (Occupational environments).

Why do regulators disagree about naphthalene?

Naphthalene has been classified by 18 agencies including IARC, US EPA, EPA CTX / IRIS, EPA CTX / IRIS, EPA CTX / NTP RoC, 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 Naphthalene in the baby app

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

Open in baby View raw API data

Sources (3)

  1. IARC Monographs Volume 82: Some Traditional Herbal Medicines, Some Mycotoxins, Naphthalene and Styrene — Naphthalene Group 2B Evaluation (2002) — regulatory
  2. US EPA: Naphthalene — IRIS Toxicological Review, Carcinogenicity Assessment and Reference Concentrations (Group C) (1998) — regulatory
  3. ASPCA Animal Poison Control Center: Naphthalene and Mothball Toxicosis in Dogs and Cats — Heinz Body Hemolytic Anemia (2022) — veterinary

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 →