Disodium methanearsonate

  • Ansar 184
  • Ansar 8100
  • Ansar dsma liquid
  • Arrhenal
  • Arsinyl
  • Arsynal
Formula
CH5AsO3 . 2Na
Structure
Description
Hydrated crystals containing 5h2o or 6h2o.
Uses
herbicide

Registry Numbers and Inventories.
CAS
144-21-8
EC (EINECS/ELINCS)
205-620-7
RTECS
PA2275000
RTECS class
Agricultural Chemical and Pesticide; Mutagen; Reproductive Effector
Beilstein/Gmelin
3915729
Beilstein Reference
2-04-00-00996
RCRA
D004
EPA OPP
13802
Swiss Giftliste 1
G-6492
Austrailia AICS
Listed
Japan ENCS (MITI)
Listed

Properties.
Formula
CH3AsO3.2Na
Formula mass
183.93
Melting point, °C
132-139
Density
1.15 g/cm3 (20 C)
Solubility in water
Soluble

Hazards and Protection.
Storage
Do not store near feed, food.
Handling
All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Protection
Goggles or face shield, rubber or neoprene gloves, rubber apron.
Respirators
Use NIOSH/MSHA approved respirator appropriate for exposure of concern.
Small spills/leaks
Evacuate area and ventilate. Wear protective equipment. If required, use an inert absrobent. Sweep up and place in an appropriate container for disposal. Wash contaminated surfaces.
Stability
Decomposed by strong oxidizing and reducing agents. Decomposes slowly at elevated temperatures. Stable to hydrolysis.

Fire.
Fire fighting
Wear goggles and self contained breathing apparatus fire extinguishing media: Dry chemical, carbon dioxide.
Fire potential
Not flammable

Health.
Exposure limit(s)
OSHA: PEL (8 h TWA): 0.5 mg/m3.
Poison_Class
3
Exposure effects
Abnormally low blood pressure and rapid heart rate are common early signs. Fever and rapid breathing may occur. Elevated blood pressure has been associated with chronic environmental arsenic exposure. Altered mental status, seizures, toxic delirium, encephalopathy, and delayed peripheral neuropathy are complications of acute arsenic poisoning. Inorganic arsenic crosses the placenta and may result in spontaneous abortion or stillbirth with either acute or chronic poisoning.
   Ingestion
Acute toxicity results in early symptoms of abdominal pain, severe vomiting and diarrhea, as well as dryness of the oral and nasal cavities.
   Inhalation
Respiratory tract irritation may occur. Cardiogenic or noncardiogenic pulmonary edema and respiratory failure may develop in severe poisonings.
   Skin
Skin findings may include hyperpigmentation, keratoses, and epidermoid carcinomas. Mee's lines of the nails are common. Trivalent arsenic compounds are corrosive to the skin. Arsenic trioxide and pentoxide are sensitizers.
   Eyes
As(III) is corrosive to the eyes, mouth, and mucous membranes. Perforation of the nasal septum can occur.

First aid
 
   Ingestion
Gastric decontamination - aggressive decontamination with gastric lavage is recommended. Activated charcoal: administer charcoal as a slurry (240 ml water/30 g charcoal). Usual dose: 25 to 100 g in adults/adolescents.
   Inhalation
If symptoms develop, move individual away from exposure and into fresh air. If symptoms persist, seek medical attention. If breathing is difficult, administer oxygen. Keep person warm and quiet; seek immediate medical attention.
   Skin
Remove contaminated clothing. Wash exposed area with soap and water. If symptoms persist, seek medical attention. Launder clothing before reuse.
   Eyes
If symptoms develop, immediately move individual away from exposure and into fresh air. Flush eyes gently with water for at least 15 minutes while holding eyelids apart; seek immediate medical attention.

Transport.