Pet Safety / Compounds / Transfluthrin

Is Transfluthrin safe for dogs and cats?

Low risk for pets

Dogs tolerate transfluthrin at typical spatial insecticide use concentrations; adequate room ventilation during coil or vaporizer operation is the primary precaution. No specific veterinary concerns at registered product use concentrations.

What is transfluthrin?

The IUPAC name is cis-(2,3,5,6-tetrafluorophenyl)methyl (1R,3S)-3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropane-1-carboxylate.

Also known as: cis-(2,3,5,6-tetrafluorophenyl)methyl (1R,3S)-3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropane-1-carboxylate, Benfluthrin, QWL3SKA6EG, Bayothrin.

IUPAC name
cis-(2,3,5,6-tetrafluorophenyl)methyl (1R,3S)-3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropane-1-carboxylate
CAS number
118712-89-3
Molecular formula
C15H12Cl2F4O2
Molecular weight
371.2 g/mol
SMILES
CC1(C(C1C(=O)OCC2=C(C(=CC(=C2F)F)F)F)C=C(Cl)Cl)C
PubChem CID
656612

Risk for dogs

Low risk

Dogs tolerate transfluthrin at typical spatial insecticide use concentrations; adequate room ventilation during coil or vaporizer operation is the primary precaution. No specific veterinary concerns at registered product use concentrations.

Risk for cats

High risk

Transfluthrin is a type I pyrethroid — cats are sensitive to sodium channel dysfunction via the T-syndrome mechanism. The primary cat exposure scenario is prolonged inhalation from indoor coils, vaporizer mats, or candles operated in rooms where cats sleep or spend extended time. In Japan, South Asia, and tropical regions, transfluthrin-based products are commonly used year-round in homes, creating sustained overnight inhalation exposure for indoor cats. Although transfluthrin's acute mammalian oral toxicity is very low, the inhalation exposure route bypasses digestive detoxification and the small cat body size amplifies effective dose. Cat owners using transfluthrin spatial insecticides should ensure cats are not present in rooms during active vaporizer operation, or use products in areas cats cannot access. Treatment: fresh air, bathing if coat contaminated, supportive care.

Regulatory consensus

1 regulatory bodyhas classified Transfluthrin.

AgencyYearClassificationNotes
WHO—Class II

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 transfluthrin

  • 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 Transfluthrin:

  • 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 transfluthrin safe for pets?

Dogs tolerate transfluthrin at typical spatial insecticide use concentrations; adequate room ventilation during coil or vaporizer operation is the primary precaution. No specific veterinary concerns at registered product use concentrations.

What products contain transfluthrin?

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

See Transfluthrin in the pets app

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

Open in pets View raw API data

Sources (3)
  1. US EPA Pyrethroid Reregistration Eligibility Decision — cypermethrin/deltamethrin/lambda-cyhalothrin/bifenthrin/cyfluthrin/fenvalerate/tau-fluvalinate/fenpropathrin; type I/II classification; aquatic toxicity; cat sensitivity; sodium channel mechanism; human paresthesia; buffer zones (2011) (2011) — regulatory
  2. ASPCA Animal Poison Control Center: Pyrethroid Toxicosis in Cats and Dogs — type I vs type II CS/T syndromes; extreme cat sensitivity (sodium channel/UGT deficiency); bathing decontamination; methocarbamol tremor control; cyproheptadine; lipid emulsion severe cases (2023) (2023) — veterinary
  3. WHO: Mosquito Coil Emissions and Health Implications — pyrethroid composition; inhalation exposure estimates; allethrin, transfluthrin, metofluthrin; ventilation recommendations; human health risk assessment; bystander exposure in endemic regions (2011) (2011) — 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 →