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METHOMYL
ICSC: 0177
Peer-Review Status: 19.10.2005 Validated
S-Methyl-N-(methylcarbamoyloxy)thioacetimidate
Ethanimidothioic acid, N-[(methylamino)carbonyl}oxy}-, methyl ester
Methyl N-{(methylamino)carbonyloxy}ethanimidothioate 
CAS #: 16752-77-5 RTECS #: AK2975000
UN #: 2757
EC #: 006-045-00-2
EINECS #: 240-815-0
    Formula: C5H10N2O2S
Molecular mass: 162.2

TYPES OF
HAZARD /
EXPOSURE
ACUTE HAZARDS / SYMPTOMS      PREVENTION      FIRST AID / FIRE FIGHTING
FIRE Combustible under specific conditions. 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. 
EXPLOSION      
 
EXPOSURE   PREVENT DISPERSION OF DUST! STRICT HYGIENE! AVOID EXPOSURE OF ADOLESCENTS AND CHILDREN!   
Inhalation Pupillary constriction, muscle cramp, excessive salivation. Muscle twitching. Dizziness. Headache. Sweating. Laboured breathing. Unconciousness.  Use local exhaust or breathing protection.  Fresh air, rest. Half-upright position. Refer for medical attention. See Notes. 
Skin   Protective gloves.  Remove contaminated clothes. Rinse skin with plenty of water or shower. 
Eyes Redness. Blurred vision.  Wear safety goggles or eye protection in combination with breathing protection.  First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention. 
Ingestion Abdominal cramps. Convulsions. Diarrhoea. Nausea. Vomiting. Weakness. Further see Inhalation.  Do not eat, drink, or smoke during work. Wash hands before eating.  Give a slurry of activated charcoal in water to drink. Refer immediately for medical attention. 

SPILLAGE DISPOSAL
PACKAGING & LABELLING
Personal protection: particulate filter respirator adapted to the airborne concentration of the substance. 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.  Unbreakable packaging.
Put breakable packaging into closed unbreakable container.
Do not transport with food and feedstuffs.
Marine pollutant. 
EC Classification
Symbol: T+, N; R: 28-50/53; S: (1/2)-22-36/37-45-60-61 
UN Classification
UN Hazard Class: 6.1; UN Pack Group: II 
GHS Classification
 

EMERGENCY RESPONSE SAFE STORAGE
Transport Emergency Card: TEC (R)-61GT7-II.  Store in an area without drain or sewer access. Dry. Keep in a well-ventilated room. Separated from strong bases and food and feedstuffs. 

IMPORTANT DATA
Physical State; Appearance
WHITE CRYSTALS WITH CHARACTERISTIC ODOUR. 

Physical dangers
 

Chemical dangers
Decomposes on heating and on burning. This produces toxic and corrosive fumes including nitrogen oxides, sulfur oxides, hydrogen cyanide and methylisocyanate. Reacts with strong bases. 

Occupational exposure limits
TLV: 2.5mg/m³ as TWA; A4 (not classifiable as a human carcinogen); BEI issued; (ACGIH 2005).
MAK (not established):. 

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

Inhalation risk
A harmful contamination of the air will not or will only very slowly be reached on evaporation of this substance at 20°C; on spraying or dispersing, however, much faster. 

Effects of short-term exposure
The substance is irritating to the eyes. 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. 

Effects of long-term or repeated exposure
The substance may have effects on the blood. This may result in anaemia. 


PHYSICAL PROPERTIES ENVIRONMENTAL DATA
Melting point: 78°C
Density: 1.3 g/cm³
Solubility in water, g/100ml at 25°C: 5.8 (moderate)
Vapour pressure at 25°C: negligible
Octanol/water partition coefficient as log Pow: 1.24  
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
Methomyl is a mixture of (Z)- and (E)-isomers.
If the pesticide is present in a formulation containing hydrocarbon solvents, vomiting should not be induced.
Specific treatment is necessary in case of poisoning with this substance; the appropriate means with instructions must be available.
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.
Do NOT take working clothes home.
Depending on the degree of exposure, periodic medical examination is suggested.
Du Pont 1179, Flytek, Lannate, Lanox, Methavin, Methomex, Nudrin are trade names.
Card has been partially updated in January 2008: see Ingestion First Aid. 

ADDITIONAL INFORMATION
 

IPCS
International
Programme on
Chemical Safety
WHO ILO EC Prepared in the context of cooperation between the International Programme on Chemical Safety and the European Commission
© IPCS 2004-2012
LEGAL NOTICE Neither the EC nor the IPCS nor any person acting on behalf of the EC or the IPCS is responsible for the use which might be made of this information.


    See Also:
       Toxicological Abbreviations
       Methomyl (EHC 178, 1996)
       Methomyl (HSG 97, 1995)
       Methomyl (PDS)
       Methomyl (WHO Pesticide Residues Series 5)
       Methomyl (Pesticide residues in food: 1976 evaluations)
       Methomyl (Pesticide residues in food: 1977 evaluations)
       Methomyl (Pesticide residues in food: 1978 evaluations)
       Methomyl (Pesticide residues in food: 1986 evaluations Part II Toxicology)
       Methomyl (Pesticide residues in food: 1989 evaluations Part II Toxicology)
       Methomyl (JMPR Evaluations 2001 Part II Toxicological)