The end of pentachlorophenol is near

The US Environmental Protection Agency is proposing to ban all uses of the wood preservative pentachlorophenol. The decision comes after the sole producer of the chemical in North America announced that it was shutting down its pentachlorophenol business by the end of this year.

Commonly called penta, the chemical is used primarily to treat wooden utility poles. The US National Toxicology Program lists pentachlorophenol as a “reasonably anticipated” human carcinogen. The chemical is banned under the United Nation’s Stockholm Convention on Persistent Organic Pollutants, a treaty the US signed but never ratified.

The EPA claims that “pentachlorophenol poses significant human health risks to workers.” To address such risks, the agency is proposing to prohibit all uses by canceling its registration under the federal pesticide law. Safer alternatives, such as copper naphthenate and dichloro-octyl-isothiazolinone, and other wood preservatives, such as chromated arsenicals and creosote, are available, the EPA says.

The decision “is by no means surprising,” Lynn Bergeson, managing partner at the law firm Bergeson & Campbell, writes in a March 5 article in the National Law Review. “The real debate will be in the terms that EPA eventually settles upon with regard to phase-out and continued use of stockpiled material,” she adds.

Environmental groups have been urging the EPA to ban pentachlorophenol for more than 20 years. “This decision has been overdue by decades, but we are encouraged to see EPA moving to remove this chemical off the market,” says Jay Feldman, executive director of the advocacy group Beyond Pesticides. In the late 1990s, the group identified about 250 Superfund waste sites contaminated with pentachlorophenol at locations across the US where the chemical was formerly produced. Because of the persistence of the chemical in the environment and its ubiquitous use on utility poles, Feldman is urging the federal government to warn people not to touch utility poles and to keep children from playing near them.

The EPA is accepting comments on its proposed decision for 60 days.