Pentachlorophenol Treated Wood

Pentachlorophenol is a manufactured chemical not found naturally in the environment. Pure pentachlorophenol occurs as a colorless crystal. The impure form is dark gray to brown dust, beads, or flakes. It has a sharp chemical odor when hot, but very little smell at room temperature. Pentachlorophenol was used as a biocide and wood preservative. It was one of the most heavily used pesticides in the United States. Now, only certified applicators can purchase and use pentachlorophenol.

It is still used in industry as a wood preservative for power line poles, railroad ties, cross arms, and fence posts. It is no longer found in wood preserving solutions or insecticides and herbicides that you can buy for home and garden use.

Unused tri-, tetra, or pentachlorophenol formulations are federal listed Hazardous Wastes with an F027 waste code. Pentachlorophenol is also a federally regulated Characteristic Hazardous Waste with a D037 waste code if there is enough of the formulation to fail a Toxicity Characteristic Leaching Procedure (TCLP) test.

Exposure to pentachlorophenol happens mostly to workers at lumber mills and wood-treatment facilities where it is used as a wood preservative. Pentachlorophenol can harm the liver, kidneys, blood, lungs, nervous system, immune system, and gastrointestinal tract. It can also irritate the skin and eyes.

The Agency for Toxic Substances and Disease Registry (ATSDR) is an agency of the U.S. Department of Health and Human Services provides ToxFAQsTM Pentachlorophenol and many others. Note that the links lead away from the Department of Ecology Web site. However, the ATSDR is the Federal government's general clearinghouse for toxicity information.

Pentachlorophenol links to the ATSDR ToxFAQsTM for this chemical.

Related information

How to Choose a Hazardous Waste or Used Oil Contractor is a help guide with advice on how to select a contractor.

 Focus on Treated Wood Exclusion is an Ecology publication that clarifies the disposal and recycling options for arsenical, pentachlorophenol, and creosote-treated wood.