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METHYLARSONIC ACID
ICSC: 0755
Peer-Review Status: 20.04.2005 Validated
Methanearsonic acid
Monomethylarsinic acid
MMA
Monomethylarsonate 
CAS #: 124-58-3 RTECS #: PA1575000
UN #: 1557
EC #: 033-002-00-5
EINECS #: 204-705-6
    Formula: CH3AsO(OH)2 / CH5AsO3
Molecular mass: 140

TYPES OF
HAZARD /
EXPOSURE
ACUTE HAZARDS / SYMPTOMS      PREVENTION      FIRST AID / FIRE FIGHTING
FIRE Not combustible. Gives off irritating or toxic fumes (or gases) in a fire.    In case of fire in the surroundings, use appropriate extinguishing media. 
EXPLOSION      
 
EXPOSURE   PREVENT DISPERSION OF DUST! AVOID ALL CONTACT!   
Inhalation Cough. Sore throat.  Use local exhaust or breathing protection.  Fresh air, rest. Refer for medical attention. 
Skin Redness.  Protective gloves.  Remove contaminated clothes. Rinse and then wash skin with water and soap. 
Eyes Redness.  Wear safety goggles 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 Abdominal pain. Diarrhoea. Vomiting.  Do not eat, drink, or smoke during work. Wash hands before eating.  Rinse mouth. Refer for medical attention . 

SPILLAGE DISPOSAL
PACKAGING & LABELLING
Personal protection: particulate filter respirator adapted to the airborne concentration of the substance. 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.  Do not transport with food and feedstuffs.
Marine pollutant. 
EC Classification
Symbol: T, N; R: 23/25-50/53; S: (1/2)-20/21-28-45-60-61; Note: A, 1 
UN Classification
UN Hazard Class: 6.1; UN Pack Group: I 
GHS Classification
 

EMERGENCY RESPONSE SAFE STORAGE
Transport Emergency Card: TEC (R)-61GT5-1.  Separated from strong bases and food and feedstuffs. Dry. Store in an area without drain or sewer access. 

IMPORTANT DATA
Physical State; Appearance
WHITE HYGROSCOPIC SOLID IN VARIOUS FORMS. 

Physical dangers
 

Chemical dangers
Decomposes on heating. This produces toxic fumes of arsenic oxides (see ICSC 0378). The solution in water is a medium strong acid. 

Occupational exposure limits
TLV: BEI issued; (ACGIH 2005). 

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

Inhalation risk
A harmful concentration of airborne particles can be reached quickly when dispersed. 

Effects of short-term exposure
The substance is mildly irritating to the eyes, skin and respiratory tract. Ingestion could cause gastroenteritis. Medical observation is indicated. 

Effects of long-term or repeated exposure
The substance may have effects on the kidneys and liver. This may result in impaired functions. This substance is carcinogenic to humans. 


PHYSICAL PROPERTIES ENVIRONMENTAL DATA
Melting point: 161°C
Solubility in water: very good 
The substance is toxic to aquatic organisms. 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
Do NOT take working clothes home.
Depending on the degree of exposure, periodic medical examination is suggested.
The recommendations on this card also apply to monosodium methanarsonate and disodium methanarsonate. 

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