Pet Safety / Compounds / Para-phenylenediamine (PPD, 1,4-benzenediamine)

Is Para-phenylenediamine (PPD, 1,4-benzenediamine) safe for dogs and cats?

High risk for pets

GHS Danger classification. Dogs lack metabolic pathways to detoxify many synthetic chemicals.

What is para-phenylenediamine (ppd, 1,4-benzenediamine)?

The IUPAC name is benzene-1,4-diamine.

Also known as: benzene-1,4-diamine, p-Phenylenediamine, 1,4-BENZENEDIAMINE, 1,4-Phenylenediamine.

IUPAC name
benzene-1,4-diamine
CAS number
106-50-3
Molecular formula
C6H8N2
Molecular weight
108.14 g/mol
SMILES
NC1=CC=C(N)C=C1
PubChem CID
7814

Risk for dogs

High risk

GHS Danger classification. Dogs lack metabolic pathways to detoxify many synthetic chemicals.

Risk for cats

High risk

GHS Danger classification. Cats lack metabolic pathways to detoxify many synthetic chemicals.

Regulatory consensus

3 regulatory and scientific bodies have classified Para-phenylenediamine (PPD, 1,4-benzenediamine). The classifications differ — that's the data.

AgencyYearClassificationNotes
EPA CTX / IARC—Group 3 - Not classifiable as to its carcinogenicity to humans
EPA CTX / Genetox—Genotoxicity: positive (Ames: positive, 28 positive / 18 negative reports)
EPA CTX / Genetox—Genotoxicity: positive (Ames: positive, 28 positive / 18 negative reports)

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 pets encounter para-phenylenediamine (ppd, 1,4-benzenediamine)

  • Industrial Facilities — Manufacturing plants, Chemical storage
  • Consumer Products — Paints, Adhesives, Cleaning products

Safer alternatives

Lower-risk approaches that achieve a similar outcome to Para-phenylenediamine (PPD, 1,4-benzenediamine):

  • Tocopherol (Vitamin E) based antioxidants
    Trade-offs: Lower thermal stability than synthetic BHT/BHA for some polymer applications.
    Relative cost: 2-5× conventional

Frequently asked questions

Is para-phenylenediamine (ppd, 1,4-benzenediamine) safe for pets?

GHS Danger classification. Dogs lack metabolic pathways to detoxify many synthetic chemicals.

What products contain para-phenylenediamine (ppd, 1,4-benzenediamine)?

Para-phenylenediamine (PPD, 1,4-benzenediamine) appears in: Manufacturing plants (Industrial facilities); Chemical storage (Industrial facilities); Paints (Consumer products); Adhesives (Consumer products).

Why do regulators disagree about para-phenylenediamine (ppd, 1,4-benzenediamine)?

Para-phenylenediamine (PPD, 1,4-benzenediamine) has been classified by 3 agencies including EPA CTX / IARC, EPA CTX / Genetox, EPA CTX / Genetox, 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 Para-phenylenediamine (PPD, 1,4-benzenediamine) in the pets app

Look up products containing para-phenylenediamine (ppd, 1,4-benzenediamine), compare to alternatives, and explore the full data record.

Open in pets View raw API data

Sources (3)
  1. PubChem Compound CID 7814 — database
  2. EPA CompTox Chemicals Dashboard — DTXSID9021138 — epa
  3. ATSDR Toxicological Profile — CAS 106-50-3 — reference

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 →