CAS number
- 108-88-3
Molecular formula
- C7H8
Formula weight
- 92.1 g/mol
Family
- Monocyclic aromatic hdrocarbons (MAH)
Compound properties list|
| Melting/boiling point | -95 °C / 110 °C | Liquid |
| Relative density | 0.87 g/cm3 | Floats on water |
| Vapour pressure | 25 mm Hg | Moderately volatile |
| Vapour density | 3.2 | Denser than air |
| Solubility in water | 525 mg/L | Low solubility |
| Henry's law constant | 6 x 10-3 atm·m3/mol | Rapid volatilization when dissolved |
| log Koc (Depending on soil or sediment characteristics) | 1.7 - 3.0* | Moderate adsorption to organic matter |
At 20 0C, toluene is a liquid that floats on water and is low to moderately volatile.
Characterized by its low solubility, it will volatilize rapidly once dissolved and adsorbs
moderately to organic matter. During a spill, this compound will evaporate in part but the majority
of the product will enter into the soil or migrate into a waterway. Liquid toluene can accumulate
along the capillary fringe (groundwater) or form a film on the water's surface which will promote
its solubilization and volatilization. The adsorbed toluene in the vadose and saturated zones will
take some time to disappear, liberating contamination in either the gaseous (primarily) or dissolved
state. The resulting dissolved plume will be generally limited in size while the gaseous plume will
be relatively large in size.
Toluene should be handled with care as it is flammable and toxic.
Toluene is an aromatic hydrocarbon naturally present in crude petroleum and in the tolu
tree. It is produced during the refining of crude oil, in making coke from coal, and as a by-product
of styrene manufacturing. Toluene is added to gasoline along with benzene and xylene. The largest
releases of toluene occur during the production, transportation and use of gasoline, which contains
about 5 to 7 % toluene by weight (more than 10 % in premium unleaded).
Toluene is also a good solvent and thus used in making paints, paint thinners, fingernail polish,
lacquers, adhesives, and rubber, as well as in some printing and leather tanning processes.
Significant quantities of toluene are released in association with the production, use and disposal
of industrial and consumer products that contain toluene.
Agency for Toxic Substances and Disease Registry (ATSDR). 2000. Toxicological
Profile for Toluene. U.S. Department of Health and Human Services, Public Health Service,
Georgia, USA. (Viewed December 2013)
Canadian Council of Ministers of the Environment. 1999. Canadian Water Quality Guidelines for
the Protection of Aquatic Life: Toluene. In: Canadian Environmental Quality Guidelines. Canadian
Council of Ministers of the Environment, Manitoba, Canada. (Viewed March 2010)
Montgomery, John H. 2007. Groundwater Chemicals, Desk Reference, Fourth Edition, CRC
Press, Taylor and Francis Group, Florida, USA.
