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METHAMIDOPHOSICSC: 0176
O,S-Dimethyl phosphoramidothioate
Phosphoramidothioic acid, O,S-dimethyl ester
April 2017
CAS #: 10265-92-6
UN #: 2783
EC Number: 233-606-0

  ACUTE HAZARDS PREVENTION FIRE FIGHTING
FIRE & EXPLOSION Combustible under specific conditions. Liquid formulations containing organic solvents may be flammable. Gives off irritating or toxic fumes (or gases) in a fire.  Risk of fire and explosion if formulations contain flammable/explosive solvents.  NO open flames.    Use water spray, powder, alcohol-resistant foam, carbon dioxide.   

 PREVENT DISPERSION OF DUST! STRICT HYGIENE! AVOID EXPOSURE OF ADOLESCENTS AND CHILDREN! FIRST AID: USE PERSONAL PROTECTION. IN ALL CASES CONSULT A DOCTOR! 
  SYMPTOMS PREVENTION FIRST AID
Inhalation Dizziness. Pupillary constriction, muscle cramp, excessive salivation. Sweating. Laboured breathing. Weakness. Abdominal cramps. Diarrhoea. Nausea. Vomiting. Muscle twitching. Convulsions. Unconsciousness.  Use ventilation (not if powder), local exhaust or breathing protection.  Remove immediately from exposure. Fresh air, rest. Half-upright position. Refer immediately for medical attention. See Notes. 
Skin MAY BE ABSORBED! Further see Inhalation.  Protective gloves. Protective clothing.  Wear protective gloves when administering first aid. Remove contaminated clothes. Rinse skin with plenty of water or shower. Refer immediately for medical attention. See Notes. 
Eyes Redness. Pain. Blurred vision.  Wear face shield or eye protection in combination with breathing protection if powder.  Rinse with plenty of water for several minutes (remove contact lenses if easily possible). Refer immediately for medical attention. 
Ingestion See Inhalation.  Do not eat, drink, or smoke during work. Wash hands before eating.  Rinse mouth. Give a slurry of activated charcoal in water to drink, but NOT if convulsions occur. Rest. Refer immediately for medical attention. 

SPILLAGE DISPOSAL CLASSIFICATION & LABELLING
Personal protection: complete protective clothing including self-contained breathing apparatus. Do NOT let this chemical enter the environment. Sweep spilled substance into covered sealable 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

skull;toxiccancer;health hazenviro;aqua
DANGER
Fatal if swallowed, in contact with skin or if inhaled
Causes eye irritation
Causes damage to nervous system
Causes damage to the nervous system through prolonged or repeated exposure
Very toxic to aquatic life 

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

STORAGE
Provision to contain effluent from fire extinguishing. Separated from food and feedstuffs. Dry. Keep in a well-ventilated room. Store in an area without drain or sewer access. 
PACKAGING
Unbreakable packaging.
Put breakable packaging into closed unbreakable container.
Do not transport with food and feedstuffs.
Marine pollutant. 
METHAMIDOPHOS ICSC: 0176
PHYSICAL & CHEMICAL INFORMATION

Physical State; Appearance
COLOURLESS CRYSTALS. 

Physical dangers
 

Chemical dangers
Decomposes on heating and on burning. This produces toxic and irritating fumes including nitrogen oxides, phosphorus oxides and sulfur oxides. Attacks mild steel and copper-containing alloys (technical grade). 

Formula: C2H8NO2PS
Molecular mass: 141.1
Melting point: 44°C
Relative density (water = 1): 1.3
Solubility in water: good
Vapour pressure, Pa at 20°C: 0.002
Octanol/water partition coefficient as log Pow: -0.66  


EXPOSURE & HEALTH EFFECTS

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

Effects of short-term exposure
The substance is irritating to the eyes. The substance may cause effects on the nervous system by a cholinesterase inhibiting effect. This may result in convulsions, respiratory failure, heart failure and death. The effects may be delayed. Medical observation is indicated. 

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

Effects of long-term or repeated exposure
The substance may have effects on the nervous system. Cholinesterase inhibition. Cumulative effects are possible. 


OCCUPATIONAL EXPOSURE LIMITS
 

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
Use of alcoholic beverages enhances the harmful effect.
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.
Isolate contaminated clothing by sealing in a bag or other container.
Do NOT take working clothes home.
If the substance is formulated with solvents also consult the ICSCs of these materials.
Carrier solvents used in commercial formulations may change physical and toxicological properties.
If the substance is present under the form of a formulation containing hydrocarbon solvents, vomiting may not be induced. 

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

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    See Also:
       Toxicological Abbreviations
       Methamidophos (HSG 79, 1993)
       Methamidophos (JMPR Evaluations 2002 Part II Toxicological)
       Methamidophos (Pesticide residues in food: 1976 evaluations)
       Methamidophos (Pesticide residues in food: 1979 evaluations)
       Methamidophos (Pesticide residues in food: 1981 evaluations)
       Methamidophos (Pesticide residues in food: 1982 evaluations)
       Methamidophos (Pesticide residues in food: 1984 evaluations)
       Methamidophos (Pesticide residues in food: 1985 evaluations Part II Toxicology)
       Methamidophos (Pesticide residues in food: 1990 evaluations Toxicology)