Baby Safety / Compounds / Esfenvalerate

Is Esfenvalerate safe for babies and kids?

Moderate risk for kids

Infants are acutely vulnerable to Esfenvalerate due to immature acetylcholinesterase regulation, higher dermal absorption per unit body weight, and frequent floor-level exposure to residues.

What is esfenvalerate?

The IUPAC name is [(S)-cyano-(3-phenoxyphenyl)methyl] (2S)-2-(4-chlorophenyl)-3-methylbutanoate.

Also known as: [(S)-cyano-(3-phenoxyphenyl)methyl] (2S)-2-(4-chlorophenyl)-3-methylbutanoate, Asana, Fenvalerate alpha, Halmark.

IUPAC name
[(S)-cyano-(3-phenoxyphenyl)methyl] (2S)-2-(4-chlorophenyl)-3-methylbutanoate
CAS number
66230-04-4
Molecular formula
C25H22ClNO3
Molecular weight
419.9 g/mol
SMILES
CC(C)C(C1=CC=C(C=C1)Cl)C(=O)OC(C#N)C2=CC(=CC=C2)OC3=CC=CC=C3
PubChem CID
10342051

Risk for babies

Moderate risk

Infants are acutely vulnerable to Esfenvalerate due to immature acetylcholinesterase regulation, higher dermal absorption per unit body weight, and frequent floor-level exposure to residues.

Neonates and infants up to 12 months have incomplete blood-brain barrier development, immature Phase I/II metabolic enzymes (particularly CYP3A4, UGT1A1), and higher gastrointestinal permeability. Equivalent doses produce higher internal concentrations and longer residence times.

What to do: Minimize infant exposure through source control. For breastfeeding mothers: reduce maternal exposure. For formula-fed infants: use certified low-migration bottles and verified water sources. Consult pediatrician regarding any concerns.

Risk for pregnant and nursing people

Elevated risk

Prenatal exposure to Esfenvalerate is associated with neurodevelopmental effects. Organophosphate/carbamate insecticides inhibit acetylcholinesterase, which plays a role in fetal brain development.

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

1 regulatory bodyhas classified Esfenvalerate.

AgencyYearClassificationNotes
EPA CTX / EPA OPP—Group E Evidence of Non-carcinogenicity for Humans

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 esfenvalerate

  • 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 Esfenvalerate:

  • 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 esfenvalerate safe for kids?

Infants are acutely vulnerable to Esfenvalerate due to immature acetylcholinesterase regulation, higher dermal absorption per unit body weight, and frequent floor-level exposure to residues.

What products contain esfenvalerate?

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

What should I do if my child is exposed to esfenvalerate?

Minimize infant exposure through source control. For breastfeeding mothers: reduce maternal exposure. For formula-fed infants: use certified low-migration bottles and verified water sources. Consult pediatrician regarding any concerns.

See Esfenvalerate in the baby app

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

Open in baby View raw API data

Sources (2)
  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

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 →