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1,2,4-TRIMETHYLBENZENEICSC: 1433 (June 2002)
Pseudocumene
CAS #: 95-63-6
UN #: 1993
EC Number: 202-436-9

  ACUTE HAZARDS PREVENTION FIRE FIGHTING
FIRE & EXPLOSION Flammable.  Above 44°C explosive vapour/air mixtures may be formed.  NO open flames, NO sparks and NO smoking.  Above 44°C use a closed system, ventilation and explosion-proof electrical equipment. Prevent build-up of electrostatic charges (e.g., by grounding).  Use alcohol-resistant foam, dry powder, carbon dioxide.  In case of fire: keep drums, etc., cool by spraying with water. 

 PREVENT GENERATION OF MISTS!  
  SYMPTOMS PREVENTION FIRST AID
Inhalation Confusion. Cough. Dizziness. Drowsiness. Headache. Sore throat. Vomiting.  Use ventilation, local exhaust or breathing protection.  Fresh air, rest. Refer for medical attention. 
Skin Redness. Dry skin.  Protective gloves.  Rinse skin with plenty of water or shower. 
Eyes Redness. Pain.  Wear safety spectacles.  First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention. 
Ingestion See Inhalation.  Do not eat, drink, or smoke during work.  Rinse mouth. Do NOT induce vomiting. Refer for medical attention . 

SPILLAGE DISPOSAL CLASSIFICATION & LABELLING
Personal protection: filter respirator for organic gases and vapours adapted to the airborne concentration of the substance. Collect leaking and spilled liquid in sealable containers as far as possible. Absorb remaining liquid in sand or inert absorbent. Then store and dispose of according to local regulations. Do NOT wash away into sewer. Do NOT let this chemical enter the environment. 

According to UN GHS Criteria

 

Transportation
UN Classification
UN Hazard Class: 3; UN Pack Group: III 

STORAGE
Fireproof. Separated from strong oxidants. Well closed. Keep in a well-ventilated room. 
PACKAGING
 
1,2,4-TRIMETHYLBENZENE ICSC: 1433
PHYSICAL & CHEMICAL INFORMATION

Physical State; Appearance
COLOURLESS LIQUID WITH CHARACTERISTIC ODOUR. 

Physical dangers
 

Chemical dangers
Decomposes on burning. This produces toxic and irritating fumes. Reacts violently with strong oxidants. This generates fire and explosion hazard. 

Formula: C9H12
Molecular mass: 120,2
Boiling point: 169°C
Melting point: -44°C
Relative density (water = 1): 0.88
Solubility in water: very poor
Relative vapour density (air = 1): 4.1
Relative density of the vapour/air-mixture at 20°C (air = 1): 1.01
Flash point: 44°C c.c.
Auto-ignition temperature: 500°C
Explosive limits, vol% in air: 0.9-6.4
Octanol/water partition coefficient as log Pow: 3.8  


EXPOSURE & HEALTH EFFECTS

Routes of exposure
The substance can be absorbed into the body by inhalation. 

Effects of short-term exposure
The substance is irritating to the eyes, skin and respiratory tract. If this liquid is swallowed, aspiration into the lungs may result in chemical pneumonitis. The substance may cause effects on the central nervous system. 

Inhalation risk
A harmful contamination of the air will be reached rather 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 defats the skin, which may cause dryness or cracking. Repeated or prolonged inhalation may cause effects on the lungs. This may result in chronic bronchitis. The substance may have effects on the central nervous system and blood. See Notes. 


OCCUPATIONAL EXPOSURE LIMITS
EU-OEL: 100 mg/m3, 20 ppm as TWA.
MAK: 100 mg/m3, 20 ppm; peak limitation category: II(2); pregnancy risk group: C 

ENVIRONMENT
The substance is toxic to aquatic organisms. Bioaccumulation of this chemical may occur in fish. 

NOTES
Use of alcoholic beverages enhances the harmful effect.
Depending on the degree of exposure, periodic medical examination is suggested.
See ICSCs 1155, 1362 and 1389.
1,3,5-Trimethylbenzene (Mesitylene) is classified as a marine pollutant. 

ADDITIONAL INFORMATION
  EC Classification
Symbol: Xn, N; R: 10-20-36/37/38-51/53; S: (2)-26-61 

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    See Also:
       Toxicological Abbreviations