Hazard
Combustible. Central nervous system
impairment, asthma, and hematologic effects.
Potential Exposure
(1,2,3-and 1,2,4-isomers): These materials
are used as solvents and in dye and perfume manufacture.
The 1,2,3-isomer is used as raw material in chemical
synthesis and as an UV stabilizer. The 1,2,4-isomer is used
as the raw material for trimellitic anhydride manufacture.
These compounds are found in diesel engine exhaust
fumes.
First aid
If this chemical gets into the eyes, remove any
contact lenses at once and irrigate immediately for at least
15 minutes, occasionally lifting upper and lower lids. Seek
medical attention immediately. If this chemical contacts the
skin, remove contaminated clothing and wash immediately
with soap and water. Seek medical attention immediately.
If this chemical has been inhaled, remove from exposure,
begin rescue breathing (using universal precautions, including
resuscitation mask) if breathing has stopped and CPR if
heart action has stopped. Transfer promptly to a medical
facility. When this chemical has been swallowed, get medical
attention. Give large quantities of water and induce
vomiting. Do not make an unconscious person vomit.
Shipping
UN3295 Hydrocarbons, liquid, n.o.s., Hazard
Class: 3; Labels: 3-Flammable liquid. UN1993 Flammable
liquids, n.o.s., Hazard Class: 3; Labels: 3-Flammable liquid,
Technical Name Required. 1,3,5-Trimethylbenzene;
UN2325, Hazard Class: 3; Labels: 3-Flammable liquid.
1,2,4-Trimethylbenzene:
Incompatibilities
Vapors may form explosive mixture with
air. Incompatible with oxidizers (chlorates, nitrates, peroxides,
permanganates, perchlorates, chlorine, bromine, fluorine,
etc.); contact may cause fires or explosions. Keep
away from alkaline materials, strong bases, strong acids,
oxoacids, epoxides.
Chemical Properties
colourless liquid
Chemical Properties
Trimethylbenzenes exists in three isomeric
forms. All isomers are clear, colorless liquids with a distinctive,
aromatic odor.
Waste Disposal
Dissolve or mix the material
with a combustible solvent and burn in a chemical incinerator
equipped with an afterburner and scrubber. All federal,
state, and local environmental regulations must be
observed.
Physical properties
Clear, colorless, flammable liquid with an aromatic odor similar to propylbenzene, ethylbenzenes,
or xylenes.
Definition
ChEBI: A trimethylbenzene carrying methyl groups at positions 1, 2 and 3. It has been found in Centaurium erythraea.
Synthesis Reference(s)
Journal of the American Chemical Society, 62, p. 2639, 1940
DOI: 10.1021/ja01867a017Organic Syntheses, Coll. Vol. 4, p. 508, 1963
Source
Detected in distilled water-soluble fractions of 87 octane gasoline (0.30 mg/L), 94 octane
gasoline (0.81 mg/L), Gasohol (0.80 mg/L), No. 2 fuel oil (0.22 mg/L), diesel fuel (0.09 mg/L),
and military jet fuel JP-4 (0.19 mg/L) (Potter, 1996).
Thomas and Delfino (1991) equilibrated contaminant-free groundwater collected from
Gainesville, FL with individual fractions of three individual petroleum products at 24–25 °C for
24 h. The aqueous phase was analyzed for organic compounds via U.S. EPA approved test method
602. Average 1,2,3-trimethylbenzene concentrations detected in water-soluble fractions of
unleaded gasoline, kerosene, and diesel fuel were 1.219, 0.405, and 0.118 mg/L, respectively.
When the authors analyzed the aqueous-phase via U.S. EPA approved test method 610, average
1,2,3-trimethylbenzene concentrations in water-soluble fractions of unleaded gasoline, kerosene,
and diesel fuel were smaller, i.e., 742, 291, and 105 μg/L, respectively.
Environmental Fate
Photolytic. Glyoxal, methylglyoxal, and biacetyl were produced from the photooxidation of
1,2,3-trimethylbenzene by OH radicals in air at 25 °C (Tuazon et al., 1986a). The rate constant for
the reaction of 1,2,3-trimethylbenzene and OH radicals at room temperature was 1.53 x 10-11
cm3/molecule?sec (Hansen et al., 1975). A rate constant of 1.49 x 10-8 L/molecule?sec was reported
for the reaction of 1,2,3-trimethylbenzene with OH radicals in the gas phase (Darnall et al., 1976).
Similarly, a room temperature rate constant of 3.16 x 10-11 cm3/molecule?sec was reported for the
vapor-phase reaction of 1,2,3-trimethylbenzene with OH radicals (Atkinson, 1985). At 25 °C, a
rate constant of 2.69 x 10-11 cm3/molecule?sec was reported for the same reaction (Ohta and
Ohyama, 1985). 2,3-Butanedione was the only products identified from the OH radical-initiated
reaction of 1,2,4-trimethylbenzene in the presence of nitrogen dioxide. The amount of 2,3-
butanedione formed decreased with increased concentration of nitrogen dioxide (Bethel et al.,
2000).
Chemical/Physical. 1,2,3-Trimethylbenzene will not hydrolyze because it does not contain a
hydrolyzable group (Kollig, 1993).
Toxics Screening Level
The acute initial threshold screening level (ITSL) for all trimethylbenzene (TMB) isomers combined is 1200 μg/m3 with 8-hr averaging time.
