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

Chlormephos

Chlormephos is a colorless liquid.

CAS 24934-91-6 C5H12ClO2PS2 234.7 g/mol Danger

01 · Identification

What Chlormephos is

Chlormephos is a colorless liquid. Its molecular formula is C5H12ClO2PS2 and its molecular weight is 234.7 g/mol.

Under the GHS it carries the signal word Danger.

CAS number24934-91-6
EC number246-538-1
Index number015-114-00-6
Molecular formulaC5H12ClO2PS2
Molecular weight234.7 g/mol

Other names for Chlormephos

  • chlormephos (ISO)
  • S-chloromethyl O,O-diethyl phosphorodithioate

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 Chlormephos
CodeHazard statement
H310 Fatal in contact with skin.
H300 Fatal if swallowed.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

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

03 · Physical and chemical properties

Chlormephos 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
Boiling point 83 °C (181.4 °F) range, midpoint shown, at 0.1 mmHg (reduced pressure) HSDB
83.06 °C (181.5 °F) range, midpoint shown, at 0.1 mmHg (reduced pressure) CAMEO
Density 1.26 g/cm³ CAMEO
1.26 g/cm³ at 20 °C HSDB
Solubility Miscible with most organic solvents HSDB
60 mg/l water at 20 °C at 20 °C HSDB
Solubility in water, g/100ml at 20 °C: 0.006 (very poor) at 20 °C ICSC
Vapor pressure 0.057 mmHg at 30 °C HSDB
0.0056 mmHg at 30 °C CAMEO
Flash point 100 °C (212 °F) above this value ICSC
Lower explosive limit (LEL) Combustible. HSDB
Corrosivity Corrosive to some metals. HSDB

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

04 · Handling and storage

Storing and handling Chlormephos

Storage conditions

Rooms used for storage only should be soundly constructed & fitted with secure locks. Floors should be kept clear & pesticides clearly identified. If repacking is carried out in storage rooms, adequate light should be available; floors should be impervious & sound ... . /Pesticides/

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

Organophosphates, such as CHLORMEPHOS, 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 Chlormephos in the storage compatibility matrix →

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