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

Chlorpyrifos

Chlorpyrifos is white granular crystals with a mild mercaptan odor.

CAS 2921-88-2 Danger

01 · Identification

What Chlorpyrifos is

Chlorpyrifos is white granular crystals with a mild mercaptan odor. It boils at 160 °C, melts at 42.2 °C.

Under the GHS it carries the signal word Danger.

CAS number2921-88-2
EC number220-864-4
Index number015-084-00-4

Other names for Chlorpyrifos

  • chlorpyrifos (ISO)
  • O,O-diethyl O-3,5,6-trichloro-2-pyridyl phosphorothioate

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 Chlorpyrifos
CodeHazard statement
H301 Toxic if swallowed.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Precautionary statements: P270, P273, P301, P310, P330, P391, P501

03 · Physical and chemical properties

Chlorpyrifos 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 160 °C (320 °F) HSDB
160 °C (320 °F) decomposes NIOSH
160 °C (320 °F) decomposes, at 760 mmHg CAMEO
Melting point 42.22 °C (108 °F) NIOSH
41.5 °C (106.7 °F) range, midpoint shown HSDB
Density 1.4 g/cm³ ICSC
1.44 g/cm³ at 20 °C HSDB
Solubility In water, 1.12 mg/L at 24 °C at 24 °C HSDB
In water, 0.39 mg/L at 19.5 °C at 19.5 °C, OECD 105 method HSDB
In water, 1.4 mg/L at 25 °C at 25 °C HSDB
Vapor pressure 0.00002 mmHg NIOSH
0.0000202 mmHg at 25 °C HSDB
0.0000187 mmHg at 25 °C CAMEO
Flash point 27.78 °C (82 °F) HSDB
30.56 °C (87 °F) HSDB
Lower explosive limit (LEL) Combustible Solid NIOSH
Vapor density 12.09 (air = 1) calculated CAMEO
12.09 (air = 1) OSHA
Corrosivity Corrosive to copper and brass HSDB

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

04 · Handling and storage

Storing and handling Chlorpyrifos

Storage conditions

Do not contaminate water, food or feed by storage or disposal. Open dumping is prohibited. ... Store in original container in secured dry storage area. Prevent cross-contamination with other pesticides and fertilizers. Do not store above 1002F for extended periods of time. If container is damaged or spills occurs, use product immediately or dispose of product ... . /Dursban W/

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Incompartible Materials: Brass

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

CHLORPYRIFOS is sensitive to heat and is decomposed by moisture. This chemical is hydrolyzed by strong alkalis. It is corrosive to copper and brass. It is also corrosive to copper alloys. It reacts with water and most reactive hydrogen compounds. The rate of hydrolysis in water increases with pH, with temperature and with the presence of copper and possibly other metals that can form chelates. (NTP, 1992)

Source: CAMEO Chemicals

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

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