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

Diazinon

Diazinon is a colorless oil with a faint ester-like odor.

CAS 333-41-5 C12H21N2O3PS 304.35 g/mol Warning

01 · Identification

What Diazinon is

Diazinon is a colorless oil with a faint ester-like odor. Its molecular formula is C12H21N2O3PS and its molecular weight is 304.35 g/mol. It boils at 120 °C, melts at 25 °C.

Under the GHS it carries the signal word Warning. It is classed as teratogens.

CAS number333-41-5
EC number206-373-8
Index number015-040-00-4
Molecular formulaC12H21N2O3PS
Molecular weight304.35 g/mol
Chemical class Teratogens

Other names for Diazinon

  • diazinon (ISO)
  • O,O-diethyl O-2-isopropyl-6-methylpyrimidin-4-yl 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 wordWarning
Hazard statements assigned to Diazinon
CodeHazard statement
H302 Harmful if swallowed.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Precautionary statements: P270, P273, P301, P312, P330, P391, P501

03 · Physical and chemical properties

Diazinon 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 120 °C (248 °F) above this value CAMEO
125 °C (257 °F) at 1 mmHg (reduced pressure) HSDB
Decomposes decomposes NIOSH
Melting point 25 °C (77 °F) below this value HMDB
Density 1.12 g/cm³ NIOSH
1.1 g/cm³ ICSC
1.117 g/cm³ at 20 °C CAMEO
Solubility Completely miscible with common organic solvents, e.g. ethers, alcohols, benzene, toluene, hexane, cyclohexane, dichloromethane, acetone, petroleum oils. HSDB
Freely soluble in ketones HSDB
Solubility in water: 0.004% at 20 °C at 20 °C HSDB
Vapor pressure 0.0001 mmHg NIOSH
0.0000901 mmHg at 25 °C HSDB
Flash point 82.22 °C (180 °F) NIOSH
104.4 °C (219.9 °F) ICSC
Autoignition temperature 400 °C (752 °F) above this value, Diazinon 50W HSDB
Lower explosive limit (LEL) Class IIIA Combustible Liquid: Fl.P. at or above 140 °F and below 200 °F. NIOSH

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

04 · Handling and storage

Storing and handling Diazinon

Storage conditions

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

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Strong acids and alkalis, copper containing compounds [Note: Hydrolyzes slowly in water and dilute acid].

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

Organothiophosphates, such as DIAZINON, 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. POISONOUS GASES ARE PRODUCED WHEN HEATED. Oxides of sulfur and of phosphorus are generated in fires (USCG, 1999).

Source: CAMEO Chemicals

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

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