Baby Safety / Compounds / Fenthion

Is Fenthion safe for babies and kids?

High risk for kids

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

What is fenthion?

The IUPAC name is dimethoxy-(3-methyl-4-methylsulfanylphenoxy)-sulfanylidene-lambda5-phosphane.

Also known as: dimethoxy-(3-methyl-4-methylsulfanylphenoxy)-sulfanylidene-lambda5-phosphane, Lebaycid, Spotton, Baytex.

IUPAC name
dimethoxy-(3-methyl-4-methylsulfanylphenoxy)-sulfanylidene-lambda5-phosphane
CAS number
55-38-9
Molecular formula
C10H15O3PS2
Molecular weight
278.3 g/mol
SMILES
CC1=C(C=CC(=C1)OP(=S)(OC)OC)SC
PubChem CID
3346

Risk for babies

High risk

Infants are acutely vulnerable to Fenthion 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 Fenthion 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

6 regulatory and scientific bodies have classified Fenthion. The classifications differ — that's the data.

AgencyYearClassificationNotes
EPA CTX / EPA OPP—Group E Evidence of Non-carcinogenicity for Humans
EPA CTX / Genetox—Genotoxicity: positive (Ames: positive, 4 positive / 4 negative reports)
EPA CTX / Genetox—Genotoxicity: positive (Ames: positive, 4 positive / 4 negative reports)
EPA CTX / Skin-Eye—Eye Irritation: Not classified (score: low)
EPA CTX / Skin-Eye—Skin Irritation: Not classified (score: low)
EPA CTX / Skin-Eye—Skin Sensitization: Not classified (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 kids encounter fenthion

  • 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 Fenthion:

  • 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 fenthion safe for kids?

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

What products contain fenthion?

Fenthion 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 fenthion?

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.

Why do regulators disagree about fenthion?

Fenthion has been classified by 6 agencies including EPA CTX / EPA OPP, EPA CTX / Genetox, EPA CTX / Genetox, 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 Fenthion in the baby app

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

Open in baby View raw API data

Sources (1)
  1. US EPA: Fenthion Reregistration Eligibility Decision — Avian Toxicity, Avicide Cancellation, Aquatic Risk, Mosquito Control Use Phase-Out (2002–2011) (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 →