Baby Safety / Compounds / Benzidine

Is Benzidine 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 Benzidine, 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 benzidine?

The IUPAC name is 4-(4-aminophenyl)aniline.

Also known as: 4-(4-aminophenyl)aniline, [1,1'-Biphenyl]-4,4'-diamine, 4,4'-Diaminobiphenyl, p-Diaminodiphenyl.

IUPAC name
4-(4-aminophenyl)aniline
CAS number
92-87-5
Molecular formula
C12H12N2
Molecular weight
184.24 g/mol
SMILES
C1=CC(=CC=C1C2=CC=C(C=C2)N)N
PubChem CID
7111

Risk for babies

Context-dependent

Pregnancy alters the metabolism and distribution of Benzidine, 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 Benzidine, 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

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

AgencyYearClassificationNotes
IARC2010Group 1 (carcinogenic to humans)IARC Monograph 99 (2010), and earlier Supplement 7. Sufficient evidence in both humans and experimental animals. Primary endpoint: urinary bladder cancer (transitional cell carcinoma). Benzidine forms reactive N-hydroxylamine metabolites that bind DNA to form adenine and guanine adducts. Among the most potent human bladder carcinogens known.
US EPA2000known to be carcinogenic to humansEPA IRIS. Oral slope factor 230 per mg/kg-day (extremely high — one of the highest carcinogenic potency values in IRIS). Inhalation unit risk 6.7 × 10⁻²per μg/m³. Benzidine and its salts are banned from manufacture and use in the US (OSHA carcinogen standard 29 CFR 1910.1010); import risk remains from azo dyes that metabolically release benzidine.
EPA CTX / NIOSHpotential occupational carcinogen
EPA CTX / IRISA (Human carcinogen)
EPA CTX / NTP RoCKnown Human Carcinogen
EPA CTX / IARCGroup 1 - Carcinogenic to humans
EPA CTX / CalEPAKnown human carcinogen
EPA CTX / GenetoxGenotoxicity: positive (Ames: positive, 22 positive / 1 negative reports)
EPA CTX / Skin-EyeSkin Sensitization: Skin sensitization - Category 1B (score: high)

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 benzidine

  • 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 Benzidine:

  • Process controls to minimize degradant formation
    Trade-offs: Additional manufacturing cost
    Relative cost: 1.2-2×

Frequently asked questions

What products contain benzidine?

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

Why do regulators disagree about benzidine?

Benzidine has been classified by 9 agencies including IARC, US EPA, EPA CTX / NIOSH, 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 Benzidine in the baby app

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

Open in baby View raw API data

Sources (3)

  1. IARC Monographs Volume 99: Benzidine and Some Azo Dyes Metabolized to Benzidine (2010) — regulatory
  2. US EPA IRIS: Benzidine — Carcinogenicity Assessment (Final) (2000) — regulatory
  3. OSHA Standard 29 CFR 1910.1010: Benzidine (Carcinogen Standard) (1974) — regulatory

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 →