Fenthion
An organic thiophosphate that is O,O-dimethyl hydrogen phosphorothioate in which the hydrogen atom of the hydroxy group is replaced by a 3-methyl-4-(methylsulfanyl)phenyl group. It exhibits acaricidal and insecticidal activities. — ChEBI
Safety documents & references
2 indexed referencesFind a product-specific SDS
Safety guides and government classification records are not a manufacturer’s SDS. Match supplier, product number, concentration, physical form, region and revision before using a document.
Identity & molecular properties
Source-linked values| CAS number | 55-38-9 | ChEBI ↗ |
| Molecular formula | C10H15O3PS2 | ChEBI ↗ |
| Molar mass | 278.335 g/mol | ChEBI ↗ |
| Monoisotopic mass | 278.02002 Da | ChEBI ↗ |
| Formal charge | 0 | ChEBI ↗ |
| ChEBI identifier | CHEBI:34761 | ChEBI ↗ |
Cross-source molecular data
PubChem| Molar mass | 278.3 g/mol | PubChem ↗ |
| Exact mass | 278.02002368 Da | PubChem ↗ |
| Computed XLogP | 4.1 | PubChem ↗ |
| Topological polar surface area (Ų) | 85.1 | PubChem ↗ |
| H-bond donors | 0 | PubChem ↗ |
| H-bond acceptors | 5 | PubChem ↗ |
| Rotatable bonds | 5 | PubChem ↗ |
PubChem computed values are shown separately from the ChEBI record. An exact InChIKey match was used to connect the records. Molecular descriptors do not describe a supplied product’s purity, particle size or performance.
Names & structural identifiers
Copy any identifierfenthionO,O-dimethyl O-[3-methyl-4-(methylsulfanyl)phenyl] phosphorothioatePNVJTZOFSHSLTO-UHFFFAOYSA-NCOP(=S)(OC)Oc1ccc(SC)c(C)c1InChI=1S/C10H15O3PS2/c1-8-7-9(5-6-10(8)16-4)13-14(15,11-2)12-3/h5-7H,1-4H3Names & synonyms
Names are supplied by ChEBI. Trade names and related synonyms may describe a broader product context.
Classification & relationships
ChEBI ontologyRoles recorded in ChEBI
Database role annotations describe reported biological or chemical roles; they are not product approvals or recommendations for use.
Safety classification · Japan
NITE / Japanese governmentO,O-Dimethyl O-(3-methyl-4-methylthiophenyl) phosphorothioate (Fenthion) · H30-B-001-MHLW, MOE
| Endpoint | Reported classification |
|---|---|
| Acute toxicity （Oral） | Category 4 |
| Acute toxicity （Dermal） | Category 3 |
| Acute toxicity （Inhalation: Dusts and mists） | Category 3 |
| Reproductive toxicity | Category 2 |
| Specific target organ toxicity - Single exposure | Category 1 (nervous system) |
| Specific target organ toxicity - Repeated exposure | Category 1 (nervous system, visual organs) |
Selected source-reported endpoints. Other endpoints, rationales and conditions remain in the original classification. Missing or unlisted information does not mean non-hazardous. This is not a global classification or transport decision.
Read the original NITE classificationMass ↔ amount of substance
Calculated from sourced massUses 278.335 g/mol from ChEBI. Assumes the substance described by this record; no purity or concentration correction is applied.
Elemental composition
Theoretical mass fractionsCSOPHCalculated theoretical mass fractions from the reported formula and PubChem periodic-table atomic masses. These are not assay or purity results.
Research & patent references
Selected source associationsSources & record history
Checked 27 Sep 2026Release 255, 9 September 2026. ChEBI three-star (manually annotated) source entry. View original record ↗ · CC BY 4.0
PubCAS formats source data, connects references and computes explicitly labelled conversions. CAS cross-references are supplied by ChEBI; they do not constitute CAS verification or endorsement.