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298-00-0 Structure

298-00-0 Structure



O,O-Dimethyl O-(p-nitrophenyl) thionophosphate

[Molecular Formula]

[MDL Number]

[Molecular Weight]

[MOL File]

Chemical PropertiesBack Directory

Methyl parathion is a white to yellow-brown, crystalline solid with a garlic odor.

white crystalline powder
[Melting point ]

[mp ]

[Boiling point ]

143°C (1.0 mmHg)
[bp ]

143°C (1.0 mmHg)
[density ]

[refractive index ]

nD25 1.5367
[Fp ]

[storage temp. ]

[form ]


Stable. Flammable.
[Water Solubility ]

0.005 g/100 mL
[Contact allergens]

A case of sensitization to methyl-parathion was described in a female agricultural worker with multiple sensitization.
[CAS DataBase Reference]

298-00-0(CAS DataBase Reference)
[NIST Chemistry Reference]

Phosphorothioic acid, o,o-dimethyl-o-p-nitrophenyl ester(298-00-0)
[EPA Substance Registry System]

298-00-0(EPA Substance)
Hazard InformationBack Directory
[Chemical Properties]

white crystalline powder

Parathion-methyl is an derivative of Parathion (P192220), an organophosphate insecticide used on cotton, rice and fruit trees.

ChEBI: A C-nitro compound that is 4-nitrophenol substituted by a (dimethoxyphosphorothioyl)oxy group at position 4.

[General Description]

Methyl parathion is a white crystalline solid dissolved in a liquid solvent carrier. The commercial product is a tan liquid (xylene solution) with a pungent odor. METHYL PARATHION, [LIQUID] is slightly soluble to insoluble in water. Usually with the liquid solvent METHYL PARATHION, [LIQUID] is a combustible liquid. METHYL PARATHION, [LIQUID] is toxic by inhalation, ingestion and skin absorption. METHYL PARATHION, [LIQUID] is used as an insecticide.
[Reactivity Profile]

METHYL PARATHION is half decomposed in 8 days at 40°C. When a sample was heated in a small test tube METHYL PARATHION, [LIQUID] decomposed in a few minutes, the residue exploded (Food Chem. 4(1):42. 1956).
[Air & Water Reactions]

Insoluble in water.

Explosion risk when heated. Toxicby skin absorption, inhalation, and ingestion;cholinesterase inhibitor. Use has been restricted.Questionable carcinogen.
[Health Hazard]

This material is extremely toxic; the probable oral lethal dose is 5-50 mg/kg, or between 7 drops and 1 teaspoonful for a 150-lb. person. Chronic toxicity does not appear to be a major consideration.
[Potential Exposure]

A severely hazardous pesticide formulation. Alert: This material is used as an insecticide on over 50 crops, primarily cotton, and on several ornamentals
[Fire Hazard]

Poisonous gases are produced in fire and when heated. Decomposition may lead to sufficient internal pressure to cause the container to rupture violently. Avoid oxidizing materials. Unstable. High temperatures (120F) cause decomposition.
[First aid]

If this chemical gets into the eyes, remove any contact lenses at once and irrigate immediately for at least 15 minutes, occasionally lifting upper and lower lids. Seek medical attention immediately. If this chemical contacts the skin, remove contaminated clothing and wash immediately with soap and water. Speed in removing material from skin is of extreme importance. Shampoo hair promptly if contaminated. Seek medical attention immediately. If this chemical has been inhaled, remove from exposure, begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR if heart action has stopped. Transfer promptly to a medical facility. When this chemical has been swallowed, get medical attention. Give large quantities of water and induce vomiting. Do not make an unconscious person vomit. Effects of exposure may be delayed. Medical monitoring is advised.

UN3017 Organophosphorus pesticides, liquid, toxic, flammable, flash point not ,23C, Hazard class: 6.1; Labels: 6.1-Poisonous materials, 3.-Flammable liquid. UN2783 Organophosphorus pesticides, solid, toxic, Hazard Class: 6.1; Labels: 6.1-Poisonous material. UN2811 Toxic solids, organic, n.o.s., Hazard Class: 6.1; Labels: 6.1- Poisonous materials, Technical Name Required

Incompatible with oxidizers, strong bases; heat. Mixtures with magnesium, or endrin may be violent or explosive. Slightly decomposed by acid solutions. Rapidly decomposed by alkalies. Explosive risk when heated above 50C. The liquid xylene solution decomposes violently @ 120C
[Waste Disposal]

Consult with environmental regulatory agencies for guidance on acceptable disposal practices. Generators of waste containing this contaminant (≥100 kg/mo) must conform to EPA regulations governing storage, transportation, treatment, and waste disposal. Incineration (816C, 0.5 second minimum for primary combustion; 1204C, 1.0 second for secondary combustion) with adequate scrubbing and ash disposal facilities. In accordance with 40CFR165, follow recommendations for the disposal of pesticides and pesticide containers. Must be disposed properly by following package label directions or by contacting your local or federal environmental control agency, or by contacting your regional EPA office
Safety DataBack Directory
[Hazard Codes ]

[Risk Statements ]

R5:Heating may cause an explosion.
R24:Toxic in contact with skin.
R26/28:Very Toxic by inhalation and if swallowed .
R48/22:Harmful: danger of serious damage to health by prolonged exposure if swallowed .
R50/53:Very Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment .
R67:Vapors may cause drowsiness and dizziness.
R66:Repeated exposure may cause skin dryness or cracking.
R51/53:Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment .
R36:Irritating to the eyes.
R20/22:Harmful by inhalation and if swallowed .
R11:Highly Flammable.
R65:Harmful: May cause lung damage if swallowed.
R38:Irritating to the skin.
[Safety Statements ]

S28:After contact with skin, wash immediately with plenty of ... (to be specified by the manufacturer) .
S36/37:Wear suitable protective clothing and gloves .
S45:In case of accident or if you feel unwell, seek medical advice immediately (show label where possible) .
S60:This material and/or its container must be disposed of as hazardous waste .
S61:Avoid release to the environment. Refer to special instructions safety data sheet .
S26:In case of contact with eyes, rinse immediately with plenty of water and seek medical advice .
S62:If swallowed, do not induce vomiting: seek medical advice immediately and show this container or label .

UN 2052/2783/2811

[HazardClass ]

[PackingGroup ]

[HS Code ]

[Safety Profile]

Poison by inhalation, ingestion, skin contact, subcutaneous, intravenous, and intraperitoneal routes. Fatal poisoning can result from skin or eye contact after very brief exposure to concentrated solution. Experimental teratogenic and reproductive effects. Questionable carcinogen. Human mutation data reported. A cholinesterase inhibitor type of insecticide. When heated to decomposition it emits very toxic fumes of NOx, POx, and SOx.
[Hazardous Substances Data]

298-00-0(Hazardous Substances Data)

LD50 in male, female rats (mg/kg): 14, 24 orally; 67, 67 dermally (Gaines)
Raw materials And Preparation ProductsBack Directory
【Raw materials】

Methanol-->Toluene-->Phosphorus oxychloride-->Sodium carbonate-->Triethylamine-->Sodium chloride-->Chlorine-->Sulfur-->Copper-->Phosphorus pentasulfide-->EMULSIFIER-->Trimethylamine-->Sulphur-->Dimethyl sulfide-->THIOPHOSPHORYL CHLORIDE-->White phosphorus-->Petroleum crude oil-->Sodium 4-nitrophenoxide-->DIMETHYLPHOSPHINOTHIOIC CHLORIDE
Material Safety Data Sheet(MSDS)Back Directory
[msds information]

methyl parathion(298-00-0).msds
Well-known Reagent Company Product InformationBack Directory
[Sigma Aldrich]

298-00-0 suppliers list
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