Pet Safety / Compounds / Ethylene glycol (antifreeze)

Is Ethylene glycol (antifreeze) safe for dogs and cats?

Extreme risk for pets

LD50 ~4.4 mL/kg in dogs. Metabolized to glycolic acid and oxalic acid, which precipitate as calcium oxalate crystals in renal tubules causing acute kidney failure. Sweet taste causes accidental ingestion. Treatment (ethanol or fomepizole) must begin within 8 hours of ingestion to be effective.

What is ethylene glycol (antifreeze)?

The IUPAC name is ethane-1,2-diol.

Also known as: ethane-1,2-diol, ETHYLENE GLYCOL, 1,2-ethanediol, glycol.

IUPAC name: ethane-1,2-diol
CAS number: 107-21-1
Molecular formula: C2H6O2
Molecular weight: 62.07 g/mol
SMILES: C(CO)O
PubChem CID: 174

Risk for dogs

Extreme risk

Risk for cats

Extreme risk

LD50 ~1.4 mL/kg in cats — far more sensitive than dogs. Less than one teaspoon is lethal to an average cat. Rapid metabolism to oxalic acid; acute renal failure develops within 24–72 hours. The 72-hour antidote window is narrow; fomepizole is less effective in cats than dogs.

Regulatory consensus

6 regulatory and scientific bodies have classified Ethylene glycol (antifreeze). The classifications differ — that's the data.

Agency	Year	Classification
EPA CTX / Genetox	—	Genotoxicity: negative (Ames: negative, 0 positive / 6 negative reports)
EPA CTX / Genetox	—	Genotoxicity: negative (Ames: negative, 0 positive / 6 negative reports)
EPA CTX / Skin-Eye	—	Eye Irritation: Category 2B (score: moderate)
EPA CTX / Skin-Eye	—	Skin Irritation: Category 2 (score: high)
EPA CTX / Skin-Eye	—	Eye Irritation: Category 6.4A (Category 2A) (score: high)
EPA CTX / Skin-Eye	—	skin sensitisation: in vivo (non-LLNA): Not likely to be sensitizing (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 pets encounter ethylene glycol (antifreeze)

Industrial Facilities — Manufacturing plants, Chemical storage areas, Waste treatment sites
Occupational Environments — Factories, Warehouses, Transportation vehicles

Safer alternatives

Lower-risk approaches that achieve a similar outcome to Ethylene glycol (antifreeze):

Physical/mechanical pest control (IPM)
Trade-offs: More labor-intensive. May not be sufficient for severe infestations.

Relative cost: 1.2-2×

Frequently asked questions

Is ethylene glycol (antifreeze) safe for pets?

What products contain ethylene glycol (antifreeze)?

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

Why do regulators disagree about ethylene glycol (antifreeze)?

Ethylene glycol (antifreeze) has been classified by 6 agencies including EPA CTX / Genetox, EPA CTX / Genetox, EPA CTX / Skin-Eye, EPA CTX / Skin-Eye, EPA CTX / Skin-Eye, 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 Ethylene glycol (antifreeze) in the pets app

Look up products containing ethylene glycol (antifreeze), compare to alternatives, and explore the full data record.

Open in pets View raw API data

Sources (2)

ASPCA Animal Poison Control Center: Ethylene Glycol (Antifreeze) Toxicity (2021) — report
Dial SM: Antifreeze ingestion: treatment. Vet Clin North Am Small Anim Pract 24(2):307–320 (1994) — journal

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 →