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

Chlorthiophos I

Chlorthiophos I is a brown liquid with crystals at low temp.

CAS 21923-23-9 C11H15Cl2O3PS2 361.2 g/mol Danger

01 · Identification

What Chlorthiophos I is

Chlorthiophos I is a brown liquid with crystals at low temp. Its molecular formula is C11H15Cl2O3PS2 and its molecular weight is 361.2 g/mol. It boils at 150 °C.

Under the GHS it carries the signal word Danger.

CAS number21923-23-9
EC number244-663-6
Index number015-115-00-1
Molecular formulaC11H15Cl2O3PS2
Molecular weight361.2 g/mol

Other names for Chlorthiophos I

  • chlorthiophos (ISO)
  • [isomeric reaction mass in which O-2,5-dichlorophenyl-4-methylthiophenyl O,O-diethyl phosphorothioate predominates]

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 Chlorthiophos I
CodeHazard statement
H300 Fatal if swallowed.
H311 Toxic 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, P330, P352, P391, P501

03 · Physical and chemical properties

Chlorthiophos I 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 150 °C (302 °F) at 760 mmHg DOE PAC
150 °C (302 °F) at 0.001 mmHg (reduced pressure) HSDB
155.28 °C (311.5 °F) range, midpoint shown, at 0.013 mmHg (reduced pressure) CAMEO
Density 1.345 g/cm³ at 20 °C CAMEO
Solubility Practically insol in water, sol in most organic solvents HSDB
Vapor pressure 0.0004 mmHg at 25 °C CAMEO
0.0000024 mmHg Haz-Map

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

04 · Handling and storage

Storing and handling Chlorthiophos I

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 CHLORTHIOPHOS, 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 Chlorthiophos I in the storage compatibility matrix →

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