CAS number
- 87-86-5
Molecular formula
- C6HCl5O
Formula weight
- 266.3 g/mol
Family
- Phenolic compounds
Compound properties list|
| Melting/boiling point | 191 °C | Solid |
| Relative density | 1.98 g/cm3 | Sinks in water |
| Vapour pressure | 5 x 10 -5 mm Hg | Very low volatility |
| Vapour density | 0 | N/A |
| Solubility in water | 3,000 mg/L | Moderately soluble |
| Henry's law constant | 5 x 10-7atm·m3/mol | Slow volatilization when dissolved |
| log Koc (Depending on soil or sediment characteristics) | 2.5 - 4.0* | Strong adsorption to organic matter |
At 20 0C, pentachlorophenol is a solid with very low volatility and moderate solubility.
Once it is dissolved, it volatilizes slowly and adsorbs strongly to organic matter. When present in
the soil, it volatilizes very slowly. Once dissolved, pentachlorophenol can reach the water table or
migrate into a waterway, where it will be diluted before volatilizing slowly. Fragments of
pentachlorophenol can also be carried into a watercourse where they will deposit at the bottom of
dissolve. Once the source is gone, the adsorbed phase will take a while to disappear, being released
in its gaseous or dissolved (primarily) forms. The resulting dissolved plume will be moderate in
size while the gaseous plume will be insignificant.
Pentachlorophenol should be handled with care as it is toxic.
Since 1986, pentachlorophenol used in Canada has been obtained from U.S. and European
manufacturers. Commercial pentachlorophenol, which is more frequently used as a wood preservative,
contains approximately 4% tetrachlorophenols and 0.1% trichlorophenols. The domestic use of
pentachlorophenol, in 1990, was restricted to exterior wood preservatives containing 3.3% to 5%
pentachlorophenol in petroleum distillates and applied as clear finishes, water repellents, or
stains. In Canada, all indoor and spray applications of chlorophenol were discontinued in 1981.
The amount of pentachlorophenol used for agricultural purposes was low when compared to the wood
treatment industry. Pentachlorophenol was used primarily to prevent wood decay in farm buildings,
fences, and storage facilities. Pentachlorophenol and its sodium salt have also been used as
herbicides and desiccants for forage seed crops, herbicides for nonfood vegetation control, biocides
for post-harvest washing of fruit and as insecticides for use in beehives, seed plots and
greenhouses.
The biocidal properties of pentachlorophenol have made it useful as an anti-algal and anti-fungal
agent in industrial boilers, cooling systems, latex paints and paper making.
Agency for Toxic Substances and Disease Registry (ATSDR). 1999. Toxicological profile
for Chlorophenols. U.S. Department of Health and Human Services, Public Health Service, Georgia,
U.S.A. (Viewed December 2013)
Canadian Council of Ministers of the Environment. 1999. Canadian water quality guidelines for
the protection of aquatic life: Pentachlorophenols. In: Canadian environmental quality
guidelines, 1999. 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, U.S.A.
