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

Parathion

Parathion is the pure material is a yellowish liquid at temperatures above 6 °C with an usually has a faint odor.

CAS 56-38-2 C10H14NO5PS 291.26 g/mol Danger

01 · Identification

What Parathion is

Parathion is the pure material is a yellowish liquid at temperatures above 6 °C with an usually has a faint odor. Its molecular formula is C10H14NO5PS and its molecular weight is 291.26 g/mol. It boils at 375 °C, melts at 6.1 °C.

Under the GHS it carries the signal word Danger. It is classed as hazardous Air Pollutants (HAPs).

CAS number56-38-2
EC number200-271-7
Index number015-034-00-1
Molecular formulaC10H14NO5PS
Molecular weight291.26 g/mol
Chemical class Hazardous Air Pollutants (HAPs)

Other names for Parathion

  • parathion (ISO)
  • O,O-diethyl O-4-nitrophenyl 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 Parathion
CodeHazard statement
H330 Fatal if inhaled.
H300 Fatal if swallowed.
H311 Toxic in contact with skin.
H372 Causes damage to organs <or state all organs affected, if known> through prolonged or repeated exposure <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Precautionary statements: P260, P270, P271, P273, P280, P301, P302, P304, P310, P314, P330, P352, P391, P501

03 · Physical and chemical properties

Parathion 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 375 °C (707 °F) at 760 mmHg HSDB
375 °C (707 °F) NIOSH
Melting point 6.1 °C (43 °F) HSDB
6.11 °C (43 °F) NIOSH
Density 1.27 g/cm³ NIOSH
1.26 g/cm³ CAMEO
1.26 g/cm³ at 25 °C HSDB
Solubility PRACTICALLY INSOL IN PETROLEUM ETHER, KEROSENE, & USUAL SPRAY OILS HSDB
COMPLETELY SOL IN ALCOHOLS, ESTERS, ETHERS, KETONES, AROMATIC HYDROCARBONS, ANIMAL & VEGETABLE OILS HSDB
SOL IN CHLOROFORM HSDB
Vapor pressure 0.00004 mmHg NIOSH
0.00000668 mmHg at 20 °C HSDB
0.0000378 mmHg at 20 °C CAMEO
Flash point 200 °C (392 °F) NIOSH
120 °C (248 °F) ICSC
140 °C (284 °F) range, midpoint shown HSDB
Lower explosive limit (LEL) CONTAINERS MAY EXPLODE WHEN HEATED. HSDB
Class IIIB Combustible Liquid: Fl.P. at or above 200 °F. NIOSH
When a sample was heated in a small test tube it decomposed & in a few minutes the residue exploded. decomposes HSDB
Upper explosive limit (UEL) Not highly flammable. (EPA, 1998) CAMEO
Odor threshold 4.00X10-2 ppm (detection in water; purity not specified) HSDB
0.470 mg/cu m HSDB
Odor Threshold: 0.476 mg/m (low); 0.4760 mg/m (high). HSDB

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

04 · Handling and storage

Storing and handling Parathion

Storage conditions

All parathion containers shall be protected from ... corrosion, mechanical damage, and sources of ignition. ... Outdoor storage facilities shall be located at least 20 feet from any dwellings, or a populated area and shall be equipped with a sprinkler system, where feasible.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Strong oxidizers, alkaline materials.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

Light-yellow liquid, it turns solid at 6 °C, a deadly poison by all routes. Organic phosphate insecticide, acts as an inhibitor of cholinesterase. Violent reaction when used as solvent to dissolve endrin. When heated to decomposition it emits very toxic fumes of oxides of sulfur, phosphorus, and nitrogen [Lewis, 3rd ed., 1993, p. 984].

Source: CAMEO Chemicals

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