EPA Designation Regulated
EPA Classification Organic Chemicals
EPA Levels 1,2 zero MCLG (mg/L)
0.001 MCLG (mg/L)
Alternative Names none
Sources Discharge from wood preserving factories
Pentachlorophenol is a carcinogenic pollutant discharged from wood preserving factories.


Pentachlorophenol is a white organic solid with needle-like crystals and a phenolic odor.


The greatest use of pentachlorophenol is as a wood preservative (fungicide). Though once widely used as an herbicide, it was banned in 1987 for these and other uses, as well as for any over-the-counter sales.

Health Effects

Some people who drink water containing pentachlorophenol well in excess of the maximum contaminant level (MCL) for many years could experience problems with their liver or kidneys and may have an increased risk of getting cancer.

EPA Data Source: Pentachlorophenol

EPA Definitions:

1Maximum Contaminant Level Goal (MCLG) - The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety and are non-enforceable public health goals.

Maximum Contaminant Level (MCL) - The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to MCLGs as feasible using the best available treatment technology and taking cost into consideration. MCLs are enforceable standards.

Maximum Residual Disinfectant Level Goal (MRDLG) - The level of a drinking water disinfectant below which there is no known or expected risk to health. MRDLGs do not reflect the benefits of the use of disinfectants to control microbial contaminants.

(TT) Treatment Technique - A required process intended to reduce the level of a contaminant in drinking water.

Maximum Residual Disinfectant Level (MRDL) - The highest level of a disinfectant allowed in drinking water. There is convincing evidence that addition of a disinfectant is necessary for control of microbial contaminants.

2 Units are in milligrams per liter (mg/L) unless otherwise noted. Milligrams per liter are equivalent to parts per million.