International Chemical Safety Cards

METHYLARSONIC ACID ICSC: 0755
METHYLARSONIC ACID
Methanearsonic acid
Monomethylarsinic acid
MAA
CH3AsO(OH)2/CH5AsO3
Molecular mass: 140.0
CAS # 124-58-3
RTECS # PA1575000
ICSC # 0755
UN # 1557
EC # 033-002-00-5
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: all extinguishing agents allowed.
EXPLOSION


 
EXPOSURE
PREVENT DISPERSION OF DUST! STRICT HYGIENE! AVOID EXPOSURE OF ADOLESCENTS AND CHILDREN!

INHALATION Cough.
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.
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 take to a doctor.
INGESTION Abdominal pain. Diarrhoea. Vomiting. Burning sensation in throat (further see Inhalation).
Do not eat, drink, or smoke during work.
Rinse mouth. Induce vomiting (ONLY IN CONSCIOUS PERSONS!). Rest. Refer for medical attention.
SPILLAGE DISPOSAL STORAGE PACKAGING & LABELLING
Sweep spilled substance into containers. Carefully collect remainder, then remove to safe place. Do NOT let this chemical enter the environment (extra personal protection: complete protective clothing including self-contained breathing apparatus).
Separated from reducing substances, food and feedstuffs. Dry.
Do not transport with food and feedstuffs.
T symbol
R: 23/25
S: 1/2-20/21-28-44
Note: A
UN Hazard Class: 6.1
UN Packing Group: II
SEE IMPORTANT INFORMATION ON BACK
ICSC: 0755 Prepared in the context of cooperation between the International Programme on Chemical Safety & the Commission of the European Communities © IPCS CEC 1993

International Chemical Safety Cards

METHYLARSONIC ACID ICSC: 0755

I
M
P
O
R
T
A
N
T

D
A
T
A
PHYSICAL STATE; APPEARANCE:
WHITE, SLIGHTLY HYGROSCOPIC SOLID IN VARIOUS FORMS.

PHYSICAL DANGERS:


CHEMICAL DANGERS:
The substance decomposes on heating or on burning producing toxic fumes (arsenic oxides - see ICSC # 0378). The solution in water is a medium strong acid, which may react with reducing substances, active metals (i.e. iron, aluminium, zinc) producing toxic gas (methylarsine).

OCCUPATIONAL EXPOSURE LIMITS (OELs):
TLV (as As): 0.2 ppm; mg/m3 (ACGIH 1991-1992).


ROUTES OF EXPOSURE:
The substance can be absorbed into the body by inhalation of its aerosol and by ingestion.

INHALATION RISK:
Evaporation at 20°C is negligible; a harmful concentration of airborne particles can, however, be reached quickly when dispersed.

EFFECTS OF SHORT-TERM EXPOSURE:
The substance irritates the eyes, the skin, and the respiratory tract. Medical observation is indicated. See Notes.

EFFECTS OF LONG-TERM OR REPEATED EXPOSURE:
The substance may have effects on the bone marrow (anaemia, leukopenia), the peripheral nervous system, and the inner organs (kidneys, liver).
PHYSICAL
PROPERTIES
 Melting point: 161°C Solubility in water: very goo
ENVIRONMENTAL
DATA
NOTES
Specific treatment is necessary in case of poisoning with this substance; the appropriate means with instructions must be available. The symptoms of acute poisoning appear soon after the exposure but may be delayed many hours. No odour warning if toxic concentrations are present. The recommendations on this Card also apply to monosodium methanarsonate and disodium methanarsonate.
NFPA Code: H 2; F 0; R 1;
ADDITIONAL INFORMATION


ICSC: 0755 METHYLARSONIC ACID
© IPCS, CEC, 1993
IMPORTANT LEGAL NOTICE: Neither the CEC or the IPCS nor any person acting on behalf of the CEC or the IPCS is responsible for the use which might be made of this information. This card contains the collective views of the IPCS Peer Review Committee and may not reflect in all cases all the detailed requirements included in national legislation on the subject. The user should verify compliance of the cards with the relevant legislation in the country of use.