Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

Methidathion

Methidathion is colorless crystals with an organophosphate odor.

CAS 950-37-8 C6H11N2O4PS3 302.3 g/mol Danger

01 · Identification

What Methidathion is

Methidathion is colorless crystals with an organophosphate odor. Its molecular formula is C6H11N2O4PS3 and its molecular weight is 302.3 g/mol. It melts at 39 °C.

Under the GHS it carries the signal word Danger. It is classed as carcinogens.

CAS number950-37-8
EC number213-449-4
Index number015-069-00-2
Molecular formulaC6H11N2O4PS3
Molecular weight302.3 g/mol
Chemical class Carcinogens

Other names for Methidathion

  • methidathion (ISO)
  • 2,3-dihydro-5-methoxy-2-oxo-1,3,4-thiadiazol-3-ylmethyl-O,O-dimethylphosphorodithioate

02 · GHS classification

Hazards and label elements

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Signal wordDanger
Hazard statements assigned to Methidathion
CodeHazard statement
H300 Fatal if swallowed.
H312 Harmful in contact with skin.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Precautionary statements: P270, P273, P280, P301, P302, P310, P312, P330, P352, P391, P501

03 · Physical and chemical properties

Methidathion properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

Property Value Conditions Source
Melting point 39 °C (102.2 °F) HSDB
39.44 °C (103 °F) range, midpoint shown CAMEO
Density 1.5 g/cm³ ICSC
1.51 g/cm³ at 20 °C HSDB
1.495 g/cm³ at 20 °C CAMEO
Solubility Solubility (all in g/L at 20 °C): ethanol (150); acetone (670); toluene (720); hexane (11); n-octanol (14) at 20 °C HSDB
In water, 187 mg/L at 20 °C at 20 °C HSDB
Soluble in benzene, methanol and xylene at >60 g/100 mL at 25 °C. Moderately soluble in chloroform and dichloromethane. at 25 °C HSDB
Vapor pressure 0.000001 mmHg OSHA
0.000001 mmHg at 20 °C CAMEO
0.00000337 mmHg at 25 °C HSDB
Flash point 100 °C (212 °F) ICSC
Corrosivity Non-corrosive HSDB

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

04 · Handling and storage

Storing and handling Methidathion

Storage conditions

Store in dry, well-ventilated, secure area out of reach of children and animals.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

Organophosphates, such as METHIDATHION, are susceptible to formation of highly toxic and flammable phosphine gas in the presence of strong reducing agents such as hydrides. Partial oxidation by oxidizing agents may result in the release of toxic phosphorus oxides.

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Methidathion in the storage compatibility matrix →

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