Poison Poles — A Report About Their Toxic Trail and Safer Alternatives The Toxic Trail


Chemical Treatment of Wood

Amount of Treated Wood Produced by Type of Preservative 
Creosote Solutions21 
91,751,000 cubic feet (15.9%) 
Oilborne Solutions22 
32,764,000 cubic feet (5.7%) 
Inorganic arsenicals/
Waterborne Solutions23 
450,596,000 cubic feet (77.8%) 
Fire Retardants 
3,763,000 cubic feet (0.6%) 
578,874,000 cubic feet 
How many poles are treated with which chemicals? 
Chem. Treated Wood (1,000  feet3) Percent
Penta/Oil  30,617  45 
Arsenicals  29,215  42 
Creosote  8,941  13 
TOTAL  68,773  100 
source: American Wood Preservers Institute, 1995 
According to the American Wood Preservers Institute (AWPI), wood treatment "extends the service life of wood products by decades."15 Sixty-nine percent of the wood treatment industry principally uses Southern Yellow Pine, although in the northwest both Douglas fir and Western Red Cedar are used.16 As AWPI acknowledges, the wood used is "subject to attack by insects, microorganisms and fungi."17 Wood preservatives protect against fungi, insects, bacteria and marine organisms.18 Most of the naturally resistant woods are considered too expensive to produce and when they are used, as is the case of Western Red Cedar in the northwest, they are always chemically-treated at the submerged base portion and often full length treated. 

In 1995, the wood preserving industry reported $3.65 billion in annual gross sales. In the same year, total volume of treated wood produced reached 578,874,000 cubic feet.19 

The largest use of pentachlorophenol and other oilborne solutions is in the treatment of utility poles. Of the 32,764,000 cubic feet of all wood treated with penta and oilborne solutions, 93 percent, or 30,617,000 cubic feet, is used in the production of utility poles. Of the 450,596,000 cubic feet of all wood treated with arsenicals, six percent, or 29,215,000 cubic feet, go into utility poles. In other words, the vast majority of pentachlorophenol is used on utility poles.20 Nevertheless, the treatment of utility poles are almost evenly split between penta and CCA, with 45 percent treated with penta, 42 percent with CCA and 13 percent with creosote. 

More Info:
Wood Preserving Facilities and Contaminated Sites by State 

"The Environmental Protection Agency plans to spend $18 million relocating people from 158 houses and 200 apartment in Pensacola, FL." The homes are neighbors with the Escambia Treating Company, where "the logs, telephone poles in the making, were dripping chemical preservatives, first creosote, then pentachlorophenol. In 1991, long after the company went bankrupt emergency team from the EPA dug up the toxic mess, piled it into a 60-foot high mound laced with dioxin and other chemicals, and stored it tight under a polyethylene cover. Mr. Kaufman, EPA engineer, suggested that 'common sense' justified the relocation. 'Very few people are going to keel over and die because of a Superfund site,' he said. 'It's the long term health risks that are the problem.'"

The New York Times, October 21, 1996. 

Treatment process

Poles must be prepared before the chemical is applied. The preparation may include peeling, drying, conditioning, incising, cutting, and framing. These processes enable the preservative to penetrate the wood better. The different types of wood treating plants, including pressure treating and thermal non-pressure treating, use varying degrees of pressure, vacuum and temperature.24 

The pressure-treating process involves placing the wood in a pressure-treating vessel where it is immersed in the preservative and then subjected to applied pressure. The excess penta is vacuumed from the vessel and the treated wood is removed, inspected, stored, and shipped. In the non-pressure process, which is used for short-term wood protection in construction where the wood will be protected from exposure to soil or weather through brick or cement barriers, penta is applied to the surface of wood by spraying, brushing, dipping, and soaking. This process is also used to control sapstain fungi by passing green lumber through a spray tunnel or by dipping the wood.25 


"Tim Skaggs died on October 17, 1991 at the age of 41 from acute lymphoblastic leukemia. Tim worked for Simpson Lumber Company at its Arcata mill starting at age 21. His initial employment as a night shift laborer resulted in his working at various jobs, including assignments to the paint line department where he handled and sawed lumber treated with Woodlife, a penta wood preservative manufactured and sold to Simpson by Champion. Tim's exposure to this dangerous and defective chemical during the period 1971 through late 1972 caused Tim's leukemia and that of his co-workers at the Arcata mill. The diagnosis of leukemia in Tim some 17 years after being exposed to this known carcinogen was consistent with the latency period for this type of chemically induced cancer. The California State Department of Health's report of that investigation documented three leukemias, including Timothy Skaggs, and one non-Hodgkins lymphoma at the Arcata plant." 
Richard Alexander, Dioxin in pentachlorophenol: A case study of cancer deaths in the lumber industry, 1996, citing "Evaluation of a Potential Cluster of Hematopoietic Cancers Among Workers in a Wood Manufacturing Mill in California,"

California Department of Health Services, Berkeley, April 12, 1990. 

Toxic releases from treatment sites

Wood preservative treatment facilities have contributed greatly to the ranks of Superfund cleanup sites. On the National Priority List (NPL) of sites identified by EPA: 
  • Arsenic has been found in at least 781 NPL sites;26 
  • Penta had been found at least 314 NPL sites;27 
  • Chromium has been found in at least 386 hazardous waste sites on the NPL;28 
  • Copper has been found at least 210 NPL sites; and,29 
  • Creosote has been found at least 38 of NPL sites.30 

Wood Preserving Plants (number per state)

National Priority List Sites
Contaminated with Penta, Creosote, Chromium or 
Arsenic [Wood treatment sites and other sites]
Depending on the process used by the treatment plant, wastes from plants include debris from clean-out of pressure cylinders and sumps, filters and removed from bag filters, sludge and wastewater, used personal protection equipment such as respirator filters. In a survey conducted for a Canadian government study, volumes of penta waste in treatment plants using the chemical varied from 0.03 to 0.94 kg solid wastes/m3 (solid wastes per cubic meter of) treated wood.31 The study assumes a 6% concentration of penta in solid waste from treatment facilities.32 The study's analysis of the content of solid wastes from CCA treatment facilities establishes a range of toxic material content: for arsenic 2.0 to 5.7%; chromium from 0.7 to 1.7%; and copper from 1.0 to 1.6%.33 

Drip residues is considered "one of the major potential sources of air-borne CCA components in treatment plants."34 Penta treated wood, "particularly immediately after treatment, emits PCP to the air and the wood may exude excess preservative."35 

Worker exposure

Exposure to wood preservative chemicals is highest among workers at wood treatment facilities.36 So much illness has resulted from worker exposure to pentachlorophenol that it is seen as a significant source of income for attorneys pursuing toxic torts.37 One study found that mean pentachlorophenol levels in the blood of workers using penta ranged from 83 to 57,600 parts per billion.38 Exposure to pentachlorophenol at maximum air concentrations allowed by Occupational Safety and Health Administration (OSHA) are estimated to produce blood levels one hundredth as high as the maximum found in this study.39 EPA estimated the lifetime cancer risk of a worker in a wood treatment plant using inorganic arsenicals as ranging from two in 100 to more than one in ten. Cancer risk for workers using penta were based on the dioxin contaminant, rather than all the ingredients. Nevertheless, cancer risk was estimated to range from seven in 1,000 to more than one in 100. EPA did not perform a quantitative risk assessment for workers exposed to creosote.40 

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