Outdoor & Yard / Compounds / Fenitrothion

Fenitrothion in the yard and garden

Moderate risk for your yard

AChE inhibitor (OP class). Anti-androgenic — AR antagonist. Thyroid disruption via HPT axis.

What is fenitrothion?

CAS number: 122-14-5
Molecular formula: C9H12NO5PS
Molecular weight: 277.23 g/mol
SMILES: COP(=S)(OC)OC1=CC(=C(C=C1)[N+](=O)[O-])C
PubChem CID: 31200

Risk for people, pets,

Moderate risk

AChE inhibitor (OP class). Anti-androgenic — AR antagonist. Thyroid disruption via HPT axis.

Regulatory consensus

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

Agency	Year	Classification
EU	2007	Not approved — non-renewal
EPA	2020	Registered for limited uses — re-evaluation ongoing
WHO	2009	Moderately hazardous (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 your yard encounter fenitrothion

Pesticide
Environmental Contaminant

Safer alternatives

Lower-risk approaches that achieve a similar outcome to Fenitrothion:

Pyrethroids (lower mammalian toxicity)
Trade-offs: Removes 95-99% of dissolved contaminants including metals, PFAS, nitrates; wastes 2-4 gallons per gallon produced (improving with newer systems); removes beneficial minerals; $0.05-0.25/gallon; requires pre-treatment for longevity.

Relative cost: 1.2-2×
Neonicotinoids (for agricultural use)
Trade-offs: Alternative approach; specific tradeoffs depend on application context, scale, and regulatory requirements. Full hazard assessment of alternative recommended before adoption to avoid regrettable substitution.

Relative cost: 1.2-2×

Frequently asked questions

Is fenitrothion safe for your yard?

AChE inhibitor (OP class). Anti-androgenic — AR antagonist. Thyroid disruption via HPT axis.

Why do regulators disagree about fenitrothion?

Fenitrothion has been classified by 3 agencies including EU, EPA, WHO, 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 Fenitrothion in the outdoor app

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

Open in outdoor View raw API data

Sources (1)

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 →