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METHYL PARATHIONICSC: 0626
October 2005
CAS #: 298-00-0O,O-Dimethyl O-4-nitrophenyl phosphorothioate
O,O-Dimethyl-p-nitrophenylthionophosphate
Phosphorothioic acid, O,O-dimethyl O-(4-nitrophenyl) ester
UN #: 2783
EINECS #: 206-050-1

  ACUTE HAZARDS PREVENTION FIRE FIGHTING
FIRE & EXPLOSION Combustible. Liquid formulations containing organic solvents may be flammable. Gives off irritating or toxic fumes (or gases) in a fire.    NO open flames.    Use water spray, foam, powder, carbon dioxide.   

 PREVENT DISPERSION OF DUST! STRICT HYGIENE! AVOID EXPOSURE OF ADOLESCENTS AND CHILDREN! IN ALL CASES CONSULT A DOCTOR! 
  SYMPTOMS ACUTE HAZARDS FIRST AID
Inhalation Sweating. Nausea. Vomiting. Dizziness. Pupillary constriction, muscle cramp, excessive salivation. Muscle twitching. Laboured breathing. Diarrhoea. Convulsions. Unconsciousness. Symptoms may be delayed. See Notes.  Use local exhaust or breathing protection.  Fresh air, rest. Artificial respiration may be needed. Refer for medical attention. 
Skin MAY BE ABSORBED! See Inhalation.  Protective gloves. Protective clothing.  Remove contaminated clothes. Rinse and then wash skin with water and soap. Refer for medical attention . 
Eyes Blurred vision.  Wear face shield or eye protection in combination with breathing protection if powder.  First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention. 
Ingestion See Inhalation.  Do not eat, drink, or smoke during work. Wash hands before eating.  Induce vomiting (ONLY IN CONSCIOUS PERSONS!). See Notes. Give a slurry of activated charcoal in water to drink. Refer immediately for medical attention. 

SPILLAGE DISPOSAL CLASSIFICATION & LABELLING
Personal protection: chemical protection suit including self-contained breathing apparatus. Do NOT let this chemical enter the environment. Sweep spilled substance into covered containers. If appropriate, moisten first to prevent dusting. Carefully collect remainder. Then store and dispose of according to local regulations. 

According to UN GHS Criteria

 

Transportation
UN Classification
UN Hazard Class: 6.1; UN Pack Group: II 

STORAGE
Store in an area without drain or sewer access. Keep in a well-ventilated room. Separated from food and feedstuffs. 
PACKAGING
Do not transport with food and feedstuffs.
Severe marine pollutant. 
METHYL PARATHION ICSC: 0626
PHYSICAL & CHEMICAL INFORMATION

Physical State; Appearance
COLOURLESS-TO-WHITE SOLID IN VARIOUS FORMS. 

Physical dangers
 

Chemical dangers
Decomposes on heating. This produces toxic fumes including nitrogen oxides, phosphorus oxides and sulfur oxides. This generates fire and explosion hazard. 

Formula: C8H10NO5PS
Molecular mass: 263.2
Decomposes at 120°C
Melting point: 35-38°C
Density: 1.4 g/cm³
Solubility in water, g/100ml: 0.006
Vapour pressure, Pa at 20°C: 0.001
Octanol/water partition coefficient as log Pow: 2-3  


EXPOSURE & HEALTH EFFECTS

Routes of exposure
The substance can be absorbed into the body by inhalation of its aerosol, through the skin and by ingestion. 

Effects of short-term exposure
The substance may cause effects on the nervous system. This may result in convulsions and respiratory depression. Cholinesterase inhibition. Exposure far above the OEL could cause death. Medical observation is indicated. 

Inhalation risk
A harmful concentration of airborne particles can be reached quickly on spraying or when dispersed, especially if powdered. 

Effects of long-term or repeated exposure
Cholinesterase inhibition. Cumulative effects are possible. See Acute Hazards/Symptoms. 


Occupational exposure limits
TLV: 0.02 mg/m3, ppm, as TWA; (skin); A4 (not classifiable as a human carcinogen); BEI issued 

ENVIRONMENT
The substance is very toxic to aquatic organisms. This substance may be hazardous to the environment. Special attention should be given to birds and bees. This substance does enter the environment under normal use. Great care, however, should be taken to avoid any additional release, for example through inappropriate disposal. 

NOTES
If the pesticide is present in a formulation containing hydrocarbon solvents, vomiting should not be induced.
Depending on the degree of exposure, periodic medical examination is suggested.
Specific treatment is necessary in case of poisoning with this substance; the appropriate means with instructions must be available.
Carrier solvents used in commercial formulations may change physical and toxicological properties.
Do NOT take working clothes home. 

ADDITIONAL INFORMATION
  EC Classification
Symbol: T+, N; R: 5-10-24-26/28-48/22-50/53; S: (1/2)-28-36/37-45-60-61 

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    See Also:
       Toxicological Abbreviations
       Methyl parathion (EHC 145, 1992)
       Methyl parathion (HSG 75, 1992)
       Methyl Parathion (FAO Meeting Report PL/1965/10/1)
       Methyl Parathion  (IARC Summary & Evaluation, Supplement7, 1987)
       Methyl Parathion (IARC Summary & Evaluation, Volume 30, 1983)