IPCS INCHEM Home
DIMETHYL HYDROGEN PHOSPHITEICSC: 1599
October 2005
CAS #: 868-85-9Dimethylphosphite
Dimethyl hydrogen phosphonate
Phosphorous acid dimethyl ester
Dimethylphosphonate
EINECS #: 212-783-8

  ACUTE HAZARDS PREVENTION FIRE FIGHTING
FIRE & EXPLOSION Combustible.  Above 70°C explosive vapour/air mixtures may be formed.  NO open flames, NO sparks and NO smoking.  Above 70°C use a closed system and ventilation.  Use foam, alcohol-resistant foam, carbon dioxide.  In case of fire: keep drums, etc., cool by spraying with water. NO direct contact with water. Combat fire from a sheltered position. 

   
  SYMPTOMS ACUTE HAZARDS FIRST AID
Inhalation Cough. Nausea. Sore throat.  Use ventilation, local exhaust or breathing protection.  Fresh air, rest. Refer for medical attention. 
Skin MAY BE ABSORBED! Redness. Pain.  Protective clothing. Protective gloves.  First rinse with plenty of water for at least 15 minutes, then remove contaminated clothes and rinse again. 
Eyes Redness. Pain.  Wear safety goggles.  First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention. 
Ingestion Diarrhoea. Nausea. Vomiting.  Do not eat, drink, or smoke during work.  Rinse mouth. Do NOT induce vomiting. Refer for medical attention . 

SPILLAGE DISPOSAL CLASSIFICATION & LABELLING
Personal protection: chemical protection suit and filter respirator for acid gases and vapours adapted to the airborne concentration of the substance. Do NOT let this chemical enter the environment. Cover the spilled material with inert absorbent. Collect leaking and spilled liquid in sealable containers as far as possible. 

According to UN GHS Criteria

 

Transportation
UN Classification
 

STORAGE
Dry. Store in an area without drain or sewer access. Separated from food and feedstuffs. See Chemical Dangers. 
PACKAGING
 
DIMETHYL HYDROGEN PHOSPHITE ICSC: 1599
PHYSICAL & CHEMICAL INFORMATION

Physical State; Appearance
COLOURLESS LIQUID. 

Physical dangers
The vapour is heavier than air. 

Chemical dangers
Decomposes rapidly on heating. This produces toxic fumes including phosphorus oxides and phosphine. Decomposes on contact with moist air above 220°C. This produces phosphoric acid and methanol. The solution in water is a strong acid. It reacts violently with bases and is corrosive. Reacts violently with acids and oxidants. 

Formula: C2H7O3P
Molecular mass: 110.1
Boiling point: 171°C
Melting point: <-60°C
Relative density (water = 1): 1.2
Solubility in water, g/100ml at 20°C: >10
Vapour pressure, kPa at 20°C: 0.135
Flash point: 70°C c.c.
Auto-ignition temperature: 237°C
Explosive limits, vol% in air: 5.8-38.1
Octanol/water partition coefficient as log Pow: -1.2  


EXPOSURE & HEALTH EFFECTS

Routes of exposure
The substance can be absorbed into the body by inhalation, through the skin and by ingestion. 

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

Inhalation risk
A harmful contamination of the air will be reached slowly on evaporation of this substance at 20°C; on spraying or dispersing, however, much faster. 

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


Occupational exposure limits
MAK: carcinogen category: 3B 

ENVIRONMENT
The substance is harmful to aquatic organisms. 

NOTES
Do NOT use in the vicinity of a fire or a hot surface, or during welding. 

ADDITIONAL INFORMATION
  EC Classification
 

All rights reserved. The published material is being distributed without warranty of any kind, either expressed or implied. Neither ILO nor WHO nor the European Commission shall be responsible for the interpretation and use of the information contained in this material.
    See Also:
       Toxicological Abbreviations
       Dimethyl Hydrogen Phosphite  (IARC Summary & Evaluation, Volume 48, 1990)
       Dimethyl Hydrogen Phosphite  (IARC Summary & Evaluation, Volume 71, 1999)