Magnesium arsenate

  • Arsenic acid, magnesium salt
Formula
Mg3(AsO4)2
Structure
Description
A white crystals or powder when pure.
Uses
Herbicide, Insecticide, Rodenticide

Registry Numbers and Inventories.
CAS
10103-50-1
EC (EINECS/ELINCS)
233-285-7
RTECS
CG1050000
RTECS class
Agricultural Chemical and Pesticide
UN (DOT)
1622
Beilstein/Gmelin
186022 (G)
RCRA
D004
EPA OPP
13504
Swiss Giftliste 1
G-4354
Canada DSL/NDSL
NDSL
US TSCA
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
As2Mg3O8
Formula mass
350.75
Melting point, °C
1345 - 1355
Density
2.60-2.61 g/cm3 (20 C)
Solubility in water
Insoluble

Hazards and Protection.
Storage
Protect conatainer against physical damage. Store in well-ventilated area away from food or food products and combustible materials. Arsenic Storage site should be close to lab so that only small quantities required for experimentation need to be carried. Carcinogens should be kept in only one section of storage area, explosion-proof refrigerator or freezer as required. The area should be appropriately labeled. An inventory should be kept showing the quantity of carcinogen and date it was acquired. Facilities for dispensing should be contiguous to storage area.
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
Wear appropriate clothing to prevent any reasonable probability of skin contact. Wear eye protection to prevent any possibility of eye contact.
Respirators
Escape from suddenly occurring respiratory hazards: respirator class(es): any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted acid gas canister having a high-efficiency particulate filter. Any appropriate escape-type, self-contained breathing apparatus.
Small spills/leaks
Keep material out of water sources and sewers.
Stability
The pH of aqueous solutions appears to be a major factor in the relative stability. Is relatively stable at neutral or alkaline pH but undergoes reduction with decreasing pH.
Incompatibilities
When water solutions of arsenicals are in contact with active metals such as iron, aluminum, zinc, arsenic, emits highly toxic fumes of As. Arsenic cmpd strong oxidizers, bromine azide, note: Hydrogen gas can react with inorganic arsenic to form the highly toxic gas arsine.
Decomposition
When heated to decomposition it emits toxic fumes of arsenic including arsine.

Fire.
Fire fighting
Extinguish fire using agent suitable for type of surrounding fire. (Material itself does not burn or burns with difficulty.) Use water in flooding quantities as fog. Use foam, dry chemical, or carbon dioxide.
Fire potential
Magnesium arsenate itself does not burn or burns with difficulty.
Hazards
Containers may explode when heated. Runoff may pollute waterways.
Combustion products
Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes.

Health.
Exposure limit(s)
TLV (as As): ppm; 0.2 mg/m3 (ACGIH 1991-1992). MAK as As: ppm; 0.01 mg/m3; OSHA PEL (1987).
Carcinogin
O, G-A1, I-1, N-1, CP65
Poison_Class
2
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
Move victim to fresh air. Apply artificial respiration if victim is not breathing. Do not use mouth-to-mouth method if victim ingested or inhaled the substance; induce artificial respiration with the aid of a pocket mask equipped with a one-way valve or other proper respiratory medical device. Administer oxygen if breathing is difficult.
   Skin
Remove and isolate contaminated clothing and shoes. Remove material from skin immediately. Immediately flush with running water for at least 20 minutes. For minor skin contact, avoid spreading material on unaffected skin.
   Eyes
Immediately flush with running water for at least 20 minutes.

Transport.
UN number
1622
Response guide
Hazard class
6.1
Packing Group
II
 
Std. Transport #
4923238