Baby Safety / Compounds / o-Toluidine (2-methylaniline)

Is o-Toluidine (2-methylaniline) safe for babies and kids?

Very high risk for kids

(Babies-specific data is limited; this page draws from human pregnant context.) Pregnancy alters the metabolism and distribution of o-Toluidine (2-methylaniline), 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 o-toluidine (2-methylaniline)?

The IUPAC name is 2-methylaniline.

Also known as: 2-methylaniline, o-Toluidine, 2-Toluidine, o-Tolylamine.

IUPAC name
2-methylaniline
CAS number
95-53-4
Molecular formula
C7H9N
Molecular weight
107.15 g/mol
SMILES
CC1=CC=CC=C1N
PubChem CID
7242

Risk for babies

Very high risk

Pregnancy alters the metabolism and distribution of o-Toluidine (2-methylaniline), potentially increasing fetal exposure. The developing embryo/fetus is vulnerable during organogenesis (weeks 3-8) and neurological development. Placental transfer should be assumed.

Suspected reproductive toxicant (GHS H361) or suspected endocrine disruptor. Precautionary approach warranted. Animal studies or limited human data suggest developmental toxicity potential.

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

Very high risk

Pregnancy alters the metabolism and distribution of o-Toluidine (2-methylaniline), potentially increasing fetal exposure. The developing embryo/fetus is vulnerable during organogenesis (weeks 3-8) and neurological development. Placental transfer should be assumed.

Suspected reproductive toxicant (GHS H361) or suspected endocrine disruptor. Precautionary approach warranted. Animal studies or limited human data suggest developmental toxicity potential.

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

Regulatory consensus

17 regulatory and scientific bodies have classified o-Toluidine (2-methylaniline). The classifications differ — that's the data.

AgencyYearClassificationNotes
IARC2010Group 1
US EPA2010likely human carcinogen
EPA CTX / NIOSHpotential occupational 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, 14 positive / 16 negative reports)
EPA CTX / GenetoxGenotoxicity: positive (Ames: positive, 14 positive / 16 negative reports)
EPA CTX / Skin-EyeEye Irritation: Eye Irrit. 2 (score: high)
EPA CTX / Skin-EyeEye Irritation: Serious eye damage/eye irritation - Category 2A (score: high)
EPA CTX / Skin-EyeEye Irritation: Category 2A (score: high)
EPA CTX / Skin-EyeSkin Irritation: Not classified (score: low)
EPA CTX / Skin-EyeEye Irritation: Eye Irrit. 2 (score: high)
EPA CTX / Skin-EyeEye Irritation: Category 6.4A (Category 2A) (score: high)
EPA CTX / Skin-Eyeskin sensitisation: in vivo (LLNA): Not likely to be sensitizing (score: low)
EPA CTX / Skin-Eyeeye irritation: in vivo: Corrosive or Irritation Persists for > 21 days (score: very high)
EPA CTX / Skin-Eyeskin irritation: in vivo: Severe Irritation (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 o-toluidine (2-methylaniline)

  • 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 o-Toluidine (2-methylaniline):

  • Natural dyes (indigo, madder, weld) where applicable
    Trade-offs: Lower colorfastness. Limited palette. Higher cost per unit.
    Relative cost: 2-5×
  • Reactive dyes with lower aquatic toxicity
    Trade-offs: Not suitable for all fiber types
    Relative cost: 1.2-2×

Frequently asked questions

What products contain o-toluidine (2-methylaniline)?

o-Toluidine (2-methylaniline) appears in: Manufacturing plants (Industrial facilities); Chemical storage areas (Industrial facilities); Factories (Occupational environments); Warehouses (Occupational environments).

Why do regulators disagree about o-toluidine (2-methylaniline)?

o-Toluidine (2-methylaniline) has been classified by 17 agencies including IARC, US EPA, EPA CTX / NIOSH, EPA CTX / NTP RoC, EPA CTX / IARC, 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 o-Toluidine (2-methylaniline) in the baby app

Look up products containing o-toluidine (2-methylaniline), compare to alternatives, and explore the full data record.

Open in baby View raw API data

Sources (3)

  1. IARC Monographs Volume 99: o-Toluidine — Group 1; Bladder Cancer in Goodyear Niagara Falls Rubber Chemical Workers; Reclassification from 2A; N-Hydroxylation Mechanism (2010) — iarc_monograph
  2. Ward et al.: Occupational Exposure to o-Toluidine and Bladder Cancer Risk — Goodyear Niagara Falls Cohort; Case-Control Analysis; Key Evidence for IARC Group 1 Reclassification (1996) — study
  3. NIOSH Hazard Review: o-Toluidine — Bladder Cancer Risk, Occupational Exposure Assessment, Recommended REL 1 ppm, Medical Surveillance Guidelines, Goodyear Cohort Follow-up (2001) — 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 →