Fact sheet: Fluorene

General information

CAS number

86-73-7

Molecular formula

C₁₃H₁₀

Formula weight

166.2 g/mol

Family

Polycyclic aromatic hydrocarbons (PAH)

Properties (at room temperature where applicable)

Environmental behaviour

At 20 ⁰C, fluorene is a solid with very low volatility. Characterized by its low solubility, it will moderately volatilize once dissolved and adsorbs strongly to organic matter. When present in soil, this compound will undergo light volatilization and solubilize slowly. Once dissolved, it will either enter into the groundwater table or migrate towards a waterway, where it will be diluted before partially volatilizing. Fragments of fluorene can also be carried into a water course where they will deposit at the bottom and slowly dissolve. Once the source has disappeared, the adsorbed fluorene will take a long time to disappear, being released in its gaseous or dissolved forms. The resulting plumes (gaseous or dissolved) will be relatively small in size.

Health and safety

Fluorene should be handled with care, as it is toxic.

Principal resources

Fluorene is a polycyclic aromatic hydrocarbon (PAH). PAHs are a group of organic compounds that contain two or more benzene rings in their structure. There are more than 100 different PAHs that generally occur as complex mixtures (example, combustion by-products such as soot). Incomplete combustion of fuels in engines, during coal coking, or when wood is burning (forest fires, wood stoves) produces PAHs. PAHs are also constituents of petroleum and coal, and they are more present in some of their derivatives like tars and asphalt. The wood preservative industry (example, creosote), aluminum smelters using Soderberg electrodes, and hazardous waste disposal sites are further contributors of anthropogenic PAHs to the environment.

Fluorene can be obtained by fractional distillation of coal tar or by passing vapors of diphenyl methane through a red-hot tube. Fluorene is used as a chemical intermediate in many chemical processes, in the formation of polyradicals for resins, in the manufacture of dyestuffs, and in chemical, biochemical or cancer research. Fluorene is more likely to be found mixed with other PAHs in commercial products like coal tar, coal tar pitch, creosote, bitumen and asphalt. Coal tar is used as a fuel in the steel industry, distilled to give coal tar pitch and creosote, and has been used in the clinical treatment of skin disorders such as eczema and dermatitis. Coal tar pitch is used primarily as a binder for aluminum smelting electrodes, but is also used in roofing, surface coatings and a variety of other applications. Creosote is used to preserve wood for railroad ties, marine pilings and telephone poles. Some creosote products are also used as a fuel by steel production. Bitumen and asphalt are used for paving roads, for sound- and water-proofing, and coating pipes.

References

Agency for Toxic Substances and Disease Registry (ATSDR). 1995. Toxicological Profile for Polycyclic Aromatic Hydrocarbons (PAHs). 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: Polycyclic Aromatic Hydrocarbons (PAHs). In: Canadian Environmental Quality Guidelines. Canadian Council of Ministers of the Environment, Manitoba, Canada. (Viewed December 2013).

Montgomery, John H. 2007. Groundwater Chemicals, Desk Reference, Fourth Edition, CRC Press, Taylor and Francis Group, Florida, USA.

National Toxicology Program. 2005. Report on Carcinogens, Twelfth Edition: Substance Profile of Polycyclic Aromatic Hydrocarbons. U.S. Department of Health and Human Services, Public Health Services, USA.(PDF, 256KB) (Viewed December 2013)