NIOSH Publication No. 2005-151:

NIOSH Pocket Guide to Chemical Hazards

September 2005

1,3,5-Trimethylbenzene

CAS
108-67-8

C6H3(CH3)3

RTECS
OX6825000
Synonyms & Trade Names

Mesitylene, Symmetrical trimethylbenzene, sym-Trimethylbenzene
DOT ID & Guide
2325 / 129

Exposure
Limits

NIOSH REL: TWA 25 ppm (125 mg/m3)
OSHA PEL†: none
IDLH
N.D. See: IDLH INDEX
Conversion
1 ppm = 4.92 mg/m3
Physical Description
Clear, colorless liquid with a distinctive, aromatic odor.
MW: 120.2
BP: 329°F
FRZ: -49°F
Sol: 0.002%
VP: 2 mmHg
IP: 8.39 eV

Sp.Gr: 0.86
Fl.P: 122°F
UEL: ?
LEL: ?

Class II Flammable Liquid
Incompatibilities & Reactivities

Oxidizers, nitric acid
Measurement Methods
OSHA PV2091
See: NMAM or OSHA Methods
Personal Protection & Sanitation
(See protection)
Skin: Prevent skin contact
Eyes: Prevent eye contact
Wash skin: When contaminated
Remove: When wet or contaminated
Change: No recommendation

First Aid
(See procedures)
Eye: Irrigate immediately
Skin: Soap wash
Breathing: Respiratory support
Swallow: Medical attention immediately
Respirator Recommendations
Not available.
Important additional information about respirator selection
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
Irritation eyes, skin, nose, throat, respiratory system; bronchitis; hypochromic anemia; headache, drowsiness, lassitude (weakness, exhaustion), dizziness, nausea, incoordination; vomiting, confusion; chemical pneumonitis (aspiration liquid)
Target Organs
Eyes, skin, respiratory system, central nervous system, blood
See also: INTRODUCTION   See ICSC CARD: 1155