EPA Requires Cancellation of Pentachlorophenol to Protect Human Health

For Release: February 4, 2022

Today, EPA issued a final registration review decision requiring the cancellation of pentachlorophenol, a wood preservative used primarily on utility poles. During the registration review process, EPA found that given the emergence of viable alternatives, the risks pentachlorophenol poses to workers’ health outweigh the benefits of its use.

Following EPA’s March 2021 proposal to cancel pentachlorophenol, for which the Agency held a 60-day comment period, this final decision concludes EPA’s registration review of pentachlorophenol and initiates the process of risk mitigation which in this case consists of cancellation. After two years, pentachlorophenol will no longer be manufactured, sold, or distributed in the United States.

EPA’s action aligns the United States with the United Nations’ Stockholm Convention on Persistent Organic Pollutants Annex A listing of pentachlorophenol, which generally requires Parties to the Convention to eliminate its production, use, import, and export. Alternatives to pentachlorophenol include copper naphthenate and DCOIT, along with well-established wood preservatives such as chromated arsenicals and creosote.

The complete phase-out of pentachlorophenol will be conducted over five years and is intended to ensure stability within the utility pole industry by giving wood treaters time to switch to alternative wood preservatives. For the next two years, registrants may continue to produce, sell, and distribute wood preservatives containing pentachlorophenol while wood treatment facilities transition to alternatives. After February 2024, wood treatment facilities will be allowed to use their existing stocks of pentachlorophenol to produce treated wood for an additional three years.

Registrants are required to submit voluntary cancellation requests to the Agency within 60 days of the publication of the final registration review decision. The Agency will then begin the cancellation process by publishing a notice of receipt of these requests in the Federal Register and opening a 30-day public comment period.

To read EPA’s final decision, see docket 













This site contains information about the chemical PentaChloroPhenol Pentachlorophenol ( C6HCl5O) is: EPA Hazardous Waste: U242; " FO27" used on utility poles. The site was established after PSEG  began to install 90 foot chemical poles on sidewalks and near schools and homes. The chemical is very dangerous and has killed children and is known to cause cancer and birth defects. The site was established after many other communities across America and Long Island began to complain of issues related to this chemical. There are alternatives to chemical poles in communities.



Draft Risk Assessment for Pentachlorophenol (PCP)



COMMENTS 2020: https://www.regulations.gov/docketBrowser?rpp=50&so=DESC&sb=postedDate&po=0&D=EPA-HQ-OPP-2014-0653






Penta-treated wood is the largest source of dioxins. It and its accompanying contaminants are persistent organic pollutants (POPs). It contains several carcinogens including tri- and tetrachlorophenol and hexachlorobenzene, dioxins and polychlorinated dibenzofurans. Ranked among some of the most noxious chemicals ever created, penta and its sister chemicals are endocrine disrupting compounds (EDCs) that mimic estrogen and cause mal-formed reproductive organs in wildlife and humans, hence, the name gender benders. EDCs make people with such abnormalities prone to reproductive cancers later in life. Elevated levels of endocrine disruptors are found in the blood of women who have experienced spontaneous abortions, infertility and menstrual disorders. They also cause immune system dysfunction. Evidence of endocrine disruption is rarely as strong as it is for penta. With EDCs such as penta it is not the amount one has in one’s system, it is the timing of the exposure since they affect fetal and early childhood development as well as visit their deadly mutagenic effects upon the victim later in life. The synergistic interactions of the many compounds that now, unfortunately, make up our chemical body burden also have a detrimental effect. A PETROLEUM DERIVATIVE: Penta is also a chlorinated hydrocarbon derived from petroleum. The deadly toxicity of oil-derived pesticides is just one more reason to leave the oil in the ground where Mother Nature put it. We need to end our addiction to oil in more ways than one.



PentaChloroPhenol (PCP)  ===> PentaChloroPhenol (Book) <===


2020 - EPA Re-Registration Risk Review











02/21/2020: NEWS Nisus' QNAP Copper Naphthenate Positioned to be Successor to Pentachlorophenol


03/01/2020 = Chemical too toxic for other countries to be made in South Carolina



SEE: Occupational Exposure to PentaChloroPhenol





** Portions of the Idaho Pole site that are not proposed for deletion include groundwater, Treated Soils Area, sediments, and saturated subsurface soils that still pose a risk to human health and environment.





Toxicity Profiles ( https://rais.ornl.gov/tox/profiles/pentachlorophenol_c_V1.html )

Condensed Toxicity Summary for PENTACHLOROPHENOL

NOTE: Although the toxicity values presented in these toxicity profiles were correct at the time they were produced, these values are subject to change. Users should always refer to the Toxicity Value Database for the current toxicity values.


Prepared by: Robert A. Young, Ph.D., D.A.B.T., Chemical Hazard Evaluation and Communication Program, Biomedical and Environmental Information Analysis Section, Health and Safety Research Division, *, Oak Ridge, Tennessee.

Prepared for: Oak Ridge Reservation Environmental Restoration Program.

*Managed by Martin Marietta Energy Systems, Inc., for the U.S. Department of Energy under Contract No. DE-AC05-84OR21400.

Pentachlorophenol, a man-made organic biocide, is often contaminated with other toxic organic chemicals such as chlorinated phenols, dioxins, and dibenzofurans (Williams, 1982; U.S. Air Force, 1989; ATSDR, 1992).

Pentachlorophenol is readily absorbed following oral or inhalation exposure and is widely and rapidly distributed throughout the body (Wagner et al., 1991; ATSDR, 1992; Jorens and Schepens, 1993). Human and animal studies have provided evidence indicating that pentachlorophenol is metabolized to various conjugated metabolites. Both the parent compound and the conjugates are excreted in the urine (Braun et al., 1979).

Assessing the potential toxicity of technical (commercial) grade pentachlorophenol is complicated by the presence of the toxic impurities that are usually present, and the effects resulting from occupational exposure are often difficult to attribute to a specific route of exposure (Jorens and Schepens, 1993). The effects in humans following acute oral exposure include increased heart and respiratory rates, elevated temperature, increased basal metabolic rate, and death (29 and 401 mg/kg) (RTECS, 1989).

Human fatalities and toxic effects including tachycardia, jaundice, and other hematologic alterations have been reported for acute and subchronic occupational (e.g., sawmill workers, herbicide sprayers) inhalation exposures to pentachlorophenol. Upper respiratory tract inflammation and bronchitis were reported for sawmill workers chronically exposed to pentachlorophenol (Baader and Bauer, 1951; Menon et al., 1958; ATSDR, 1992). However, dose-terms for these exposures were not available, and concurrent exposures to other chemicals make definitive assessments impossible.

Data regarding the dermal exposure of humans to pentachlorophenol are anecdotal or equivocal, lack dose terms, and are compromised by concurrent exposures to other chemicals including the known contaminants in technical-grade pentachlorophenol. Acute exposure to 0.4% pentachlorophenol produced localized irritation (Bevenue et al., 1967), and subchronic exposures have caused chloracne (Baader and Bauer, 1951; O'Malley et al., 1990) and possibly renal damage (ATSDR, 1992). Dermal lesions including pemphigus and chronic urticaria have been reported for humans chronically exposed to pentachlorophenol-treated wood (Lambert et al., 1986). There currently are no definitive data regarding reproductive toxicity in humans exposed to pentachlorophenol.

Acute oral exposure of animals to pentachlorophenol affects the liver, kidneys, cardiovascular system, and the peripheral and central nervous system. Oral LD50 values for laboratory animals range from 27 to 230 mg/kg (Borzelleca et al., 1985; U.S. Air Force, 1989; ATSDR, 1992). Definitive data regarding the effects of subchronic or chronic oral exposure of humans to pentachlorophenol are not available. However, subchronic exposure (1 to 8 months) of rats to pentachlorophenol at doses ranging from 5 to 40 mg/kg/day has produced cardiovascular, hematotoxic, renal, hepatic, and immunologic responses (Schwetz et al., 1974, 1978; U.S. Air Force, 1989; ATSDR, 1992). Evidence of reproductive/developmental toxicity (increased resorptions, embryolethality, embryotoxicity, and teratogenicity) have also been observed in rats given pentachlorophenol during gestation (Larsen et al., 1974, 1976; Schwetz et al., 1978).

Because the most significant acute toxic effect of pentachlorophenol is elevated metabolism, a specific target organ or tissue is difficult to identify. However, for subchronic and chronic exposures, toxicity data indicate that the liver, kidney, and cardiovascular system are targets for some of the toxic effects of pentachlorophenol.






What is PentaChloroPhenol (PCP)




GENERAL INFORMATION 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. The major source of pentachlorophenol in drinking water is discharge from wood-preserving factories.


See Reference: https://ohiowatersheds.osu.edu/node/1573

PentaChloroPhenol is Mixed with Petroleum Crude Oil in order to make the liquid "mixture" used for Utility Poles and Cross Arms.

See EPA Decision Document 2008 for PentaChloroPhenol Registration CLICK HERE





Stockholm International Treaty on POPs Achieves Global Ban on PentaChloroPhenol














Pentachlorophenol (PCP) The insecticide PCP is classified as a persistent organic pollutant under the Stockholm Convention. PCP is a multipurpose pesticide that has mainly been used as a wood preservative. It has also been used as a biocide in the leather and textile industries. In Europe and North America, the sale to consumers of products containing PCP has been restricted since the 1990s. PCP was classified by the Working Group as carcinogenic to humans (Group 1), based on sufficient evidence that PCP causes non-Hodgkin lymphoma in humans. In all of the available epidemiological studies, exposure to PCP was positively associated with non-Hodgkin lymphoma.


https://www.iarc.fr/en/media-centre/iarcnews/pdf/Volume 117_news item.pdf











Chemicals from Old Poultry Houses Can Contaminate Eggs



























Preservative-Treated Wood and Alternative Products in the Forest Service

Appendix A—EPA-Approved Consumer Information Sheets for Wood Pressure Treated With Pentachlorophenol or Creosote


Consumer Information

This wood has been preserved by pressure-treatment with an EPA-registered pesticide containing pentachlorophenol to protect it from insect attack and decay. Wood treated with pentachlorophenol should be used only where such protection is important. Pentachlorophenol penetrates deeply into and remains in the pressure-treated wood for a long time. Exposure to pentachlorophenol may present certain hazards. Therefore, the following precautions should be taken both when handling the treated wood and in determining where to use and dispose of the treated wood.

Use Site Precautions

  • Logs treated with pentachlorophenol should not be used for log homes.
  • Wood treated with pentachlorophenol should not be used where it will be in frequent or prolonged contact with bare skin (for example, chairs and other outdoor furniture), unless an effective sealer has been applied.
  • Pentachlorophenol-treated wood should not be used in residential, industrial, or commercial interiors except for laminated beams or building components that are in ground contact and are subject to decay or insect infestation and where two coats of an appropriate sealer are applied. Sealers may be applied at the installation site. Urethane, shellac, latex epoxy enamel, and varnish are acceptable sealers for pentachlorophenol-treated wood.
  • Wood treated with pentachlorophenol should not be used in the interiors of farm buildings where there may be direct contact with domestic animals or livestock that may crib (bite) or lick the wood.
  • In interiors of farm buildings where domestic animals or livestock are unlikely to crib (bite) or lick the wood, pentachlorophenol-treated wood may be used for building components which are in ground contact and are subject to decay or insect infestation and where two coats of an appropriate sealer are applied. Sealers may be applied at the installation site.
  • Do not use pentachlorophenol-treated wood for farrowing or brooding facilities.
  • Do not use treated wood under circumstances where the preservative may become a component of food or animal feed. Examples of such sites would be structures or containers for storing silage or food.
  • Do not use treated wood for cutting boards or countertops.
  • Only treated wood that is visibly clean and free of surface residue should be used for patios, decks, and walkways.
  • Do not use treated wood for construction of those portions of beehives that may come into contact with the honey.
  • Pentachlorophenol-treated wood should not be used where it may come into direct or indirect contact with public drinking water, except for uses involving incidental contact such as docks and bridges.
  • Do not use pentachlorophenol-treated wood where it may come into direct or indirect contact with drinking water for domestic animals or livestock, except for uses involving incidental contact such as docks and bridges.

Handling Precautions

  • Dispose of treated wood by ordinary trash collection or burial.
  • Treated wood should not be burned in open fires or in stoves, fireplaces, or residential boilers because toxic chemicals may be produced as part of the smoke and ashes. Treated wood from commercial or industrial use (e.g., construction sites) may be burned only in commercial or industrial incinerators or boilers rated at 20 million British Thermal Units/hour or greater heat input or its equivalent in accordance with State and Federal regulations.
  • Avoid frequent or prolonged inhalation of sawdust from treated wood. When sawing and machining treated wood, wear a dust mask. Whenever possible, these operations should be performed outdoors to avoid indoor accumulations of airborne sawdust from treated wood.
  • When power-sawing and machining, wear goggles to protect eyes from flying particles.
  • Avoid frequent or prolonged skin contact with pentachlorophenol-treated wood.
  • When handling the treated wood, wear long-sleeved shirts and long pants and use gloves impervious to the chemicals (for example, gloves that are vinyl-coated).
  • After working with the wood, and before eating, drinking, and using tobacco products, wash exposed areas thoroughly.
  • If oily preservatives or sawdust accumulates on clothes, launder before reuse. Wash work clothes separately from other household clothing.


Utility poles installed in a Kenmore wetland. October - 2016



















"Dr. David Schindler, a water expert at the University of Alberta, said at the time that the arsenic, creosote compounds and pentachlorophenol left in the soil and groundwater when Domtar closed its plant in 1987 were "pretty nasty chemicals."















With respect to federal regulatory requirements for pesticide products, the   phrase “the label is the law” is key. You can look up currently registered pentachlorophenol products and their EPA-approved labeling using the National Pesticide Information Retrieval System (https://ppis.ceris.purdue.edu/), a publicly accessible portal to the EPA's registered pesticide database hosted by Purdue University.






Dermal exposure to pentachlorophenol was associated with

non-Hodgkin's lymphoma, multiple myeloma, and kidney cancer,



====> Click here to read about non-Hodgkin's Lymphoma.


====> Click here to read about Multiple Myeloma.


====> Click here to read about Kidney Cancer.


====> Click here to read about Hematopoietic Cancer


====> Click here to read about Prostate Cancer


====> Click here to read about Acute Lymphatic Leukemia Also See (NIH REPORT HERE)


====> Click here to read about PentaChloroPehnol in Pregnant Woman (NIH Report)




The updated cohort study focusing on pentachlorophenol provides increased statistical power and precision, and demonstrates associations between hematopoietic cancer and pentachlorophenol exposure not observed in earlier evaluations of this cohort. 




The pentachlorophenol studies presented considerable evidence pertaining to hematopoietic cancers, with strong associations seen in multiple studies, in different locations, and using different designs. There is little evidence of an association between these cancers and chlorophenols that contain fewer than four chlorines. The extension of a large cohort study of sawmill workers, with follow-up to 1995, provided information about risks of relatively rare cancers (e.g., non-Hodgkin lymphoma, multiple myeloma), using a validated exposure assessment procedure that distinguishes between exposures to pentachlorophenol and tetrachlorophenol. In contrast with dioxin, pentachlorophenol exposure has not been associated with total cancer incidence or mortality.




Chloracne associated with employment in the production of PentaChloroPhenol.


To evaluate the association between exposure to pentachlorophenol (PCP) and the occurrence of chloracne, we studied the medical and personnel records for individuals employed in the manufacturing of PCP. Forty-seven cases of chloracne were identified among 648 workers (7.0%) assigned to PCP production at a single plant between 1953 and 1978. The annual incidence rate varied considerably, ranging from 0 (in 1953) to 1.46 (in 1978). No linear trend in the risk of chloracne was observed with the duration of employment in the pentachlorophenol department. Workers with a documented episode of direct skin contact with PCP had a significantly increased risk of chloracne compared with workers who did not have a documented episode of direct skin contact (cumulative incidence ratio = 4.6; 95% confidence interval 2.6-8.1). Our results confirm that chloracne is associated with exposure to PCP contaminated with hexachlorinated, heptachlorinated, and octachlorinated dibenzo-p-dioxins and dibenzofurans.


Chloracne from pentachlorophenol-preserved wood


Abstract A patient is presented who developed chloracne after exposure to lumber which was pressure-treated with pentachlorophenol (PCP). It was presumed that his disease arose via percutaneous absorption of polychlorinated aromatic compounds (dioxins and furans) which are known to contaminate technical grade PCP. The patient's condition improved after treatment with oral isotretinoin.



Pentachlorophenol and by-products of its synthesis are complex mixtures of chemicals used as wood preservatives. Because virtually everyone who is exposed to pentachlorophenol is also exposed to its synthesis by-products, they were evaluated together. In the United States, pentachlorophenol has been regulated since the 1980s as a restricted-use pesticide. It is used industrially for treating utility poles, wood pilings, fence posts, and lumber or timber for construction. Most exposure has occurred in settings where workers treat lumber or come in contact with treated lumber. People may also be exposed to this mixture from breathing contaminated air or dust, or from contact with contaminated soil. Exposure to this mixture was associated with an increased risk of non-Hodgkin lymphoma in studies in humans.






The potential for short-term (acute) exposure to cause health effects also was considered in developing health-based SCOs. Acute toxicity reference doses were derived for seven Priority List contaminants (arsenic, barium, cadmium, copper, cyanide, nickel, naphthalene, pentachlorophenol, and phenol) that had been identified in the scientific literature as being of particular concern for acute soil exposure.


Cell / DNA Death - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3935892/pdf/pone.0089483.pdf


National Institute of Health - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3935892/


CDC - Center for Disease Control and Prevention - https://www.cdc.gov/niosh/ipcsneng/neng0069.html


International Programme on Chemical Safety - https://www.inchem.org/documents/icsc/icsc/eics0069.htm


2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD)










The Law


N.Y. PBH. LAW 3380 : NY Code - Section 3380: Inhalation of certain toxic vapors or fumes, and certain hazardous inhalants; sale of glue and hazardous inhalants in certain cases 1. (a) As used in this section the phrase "glue containing a solvent having the property of releasing toxic vapors or fumes" shall mean and include any glue, cement, or other adhesive containing one or more of the following chemical compounds: acetone, cellulose acetate, benzene, butyl alcohol, ethyl alcohol, ethylene dichloride, ethylene trichloride, isopropyl alcohol, methyl alcohol, methyl ethyl ketone, pentachlorophenol, petroleum ether, toluene or such other similar material as the commissioner shall by regulation prescribe. (b) As used in this section hazardous inhalants shall mean and include any of the preparations of compounds containing one or more of the chemical compounds; amyl nitrite, isoamyl nitrite, butyl nitrite, isobutyl nitrite, pentyl nitrite or any other akyl nitrite compound that is either designed to be used, or commonly used, as an inhalant.















Vietnam Chemicals = PentaChloroPhenol used in Okinawa


Okinawa: the junk heap of the Pacific

Listen to section - 22:47

Decades of Pentagon pollution poison service members, residents and future plans for the island.


1971: Surplus U.S. herbicides containing pentachlorophenol

contaminate civilian water supplies in

Haebaru and Gushikami districts.


Other U.S. veterans and Okinawa civilians interviewed by The Japan Times recall how surplus stocks of Agent Orange

were sold on the black market to local farmers who valued its potent weed-killing power. The risks of the unregulated

sale of hazardous substances to those lacking the necessary safety training became clear in 1971 when large volumes

of pentachlorophenol herbicides — obtained from the U.S. military by a civilian company — were dumped in the

Haebaru and Gushikami districts of southern Okinawa. The chemicals leaked into Kokuba River and the water supply

to 30,000 people had to be halted; children attending local schools suffered from abdominal pains and nausea.

35 Years after pentachlorophenol dioxin used in Vietnam. Listen to her talk about the “smell”.


Spills - Oil and Hazardous Substances. Oil spills can harm animal and plant life, contaminating food sources and nesting habitats. Petroleum oils can form tars that persist in the environment for years. The CWA prohibits oil or hazardous substance spills in quantities that may be harmful to human health and the environment and requires actions to prevent future spills.







Fact Sheet on Chemically Treated Wood Utility Poles


https://www.beyondpesticides.org/wood/resources/Fact Sheet Revised Treated Wood 2-21-03.pdf

• Wood preservatives used to chemically treat wood utility poles contain dangerous chemicals, including dioxins, which harm
human health and the environment. The last legal remaining use of pentachlorophenol (penta) is as a wood preservative in utility poles.

• There are approximately 135 million chemically treated wood utility poles in the U.S. Three percent of these poles are replaced annually.

• Wood preservatives account for nearly one-third of the 2.4 billion pounds of pesticides annually used in the U.S. Nearly 600
million cubic feet of wood poles (approx. four million poles) are treated with these chemicals each year.

• The three major chemical wood preservatives are pentachlorophenol (penta), creosote, and arsenicals (copper chromium arsenate,
or CCA). A fourth, copper naphthenate, is considered an alternative.

• Chemical treating of wood poles is one of the last remaining uses of penta and creosote – 43% of all poles are treated with penta; 42% of all poles are treated with arsenic; and 13% are still treated with creosote.

• The use of penta is prohibited in 26 countries around the world, but not in the United States.

• Penta and its contaminants, dioxin, furans, and hexochlorobenzene are considered the United Nations Environmental Program to be persistent organic pollutants (POPs). These contaminants are restricted under the Stockholm Convention on Persistent Organic Pollutants signed by the United States in 2001.

• Wood preservatives are ranked among the most potent cancer agents. They are also promoters of birth defects, reproductive problems and nervous system toxicants. The Environmental Protection Agency (EPA) assigned a cancer risk 3.4 million times higher than acceptable for people that apply penta to poles in the field, according to EPA’s draft science chapter on penta that was released in 1999.

• There are at least 795 wood preserving plants in the U.S. whose operations and waste products are not adequately regulated.

• In 1984, EPA issued a standard to limit dioxin contamination in penta to 1 part per million (ppm). In 1986, under pressure from the chemical industry, lead by the sole producer of penta in the U.S., Vulcan Chemical Co., EPA agreed to raise the dioxin levels by 4 times to 4 ppm. in some cases. This issue has not been revisited since 1986.

• The wood preserving industries strive to deny and avoid the cost and potential liability of the disposal of treated poles. A Beyond Pesticides/NCAMP study found that more than 60% of utilities regularly give away poles taken out of service. Given EPA’s concern for residential exposure this practice may have to stop.

• Poles made of alternative materials, such as recycled steel, concrete, composite, or the burying of lines, are all alternatives to wood poles that currently are used. The salvage value of steel poles contrasts sharply with the disposal costs of treated wood utility poles.

• In 2001, the European Union severely restricted the sales and use of creosote after an EU scientific committee concluded from a recent study that creosote has a greater potential to cause cancer than previously thought.

• In February 2002, EPA released for comment a preliminary agreement with the three major manufactures of CCA to end
manufacturing of wood preserved with CCA for residential use by the end of December 2003. As of February 20




This Public Health Statement is the summary chapter from theToxicological Profile for Pentachlorophenol. It is one in a series of Public Health Statements about hazardous substances and their health effects. A shorter version, theToxFAQsTM, is also available. This information is important because this substance may harm you. The effects of exposure to any hazardous substance depend on the dose, the duration, how you are exposed, personal traits and habits, and whether other chemicals are present. For more information, call the ATSDR Information Center at 1-800-232-4636.

This public health statement tells you about pentachlorophenol and the effects of exposure. The Environmental Protection Agency (EPA) identifies the most serious hazardous waste sites in the nation. These sites make up the National Priorities List (NPL) and are the sites targeted for long-term federal cleanup activities. Pentachlorophenol has been found in at least 313 of the 1,585 current or former NPL sites. However, the total number of NPL sites evaluated for this substance is not known. As more sites are evaluated, the sites at which pentachlorophenol is found may increase. This information is important because exposure to this substance may harm you and because these sites may be sources of exposure.


When a substance is released from a large area, such as an industrial plant, or from a container, such as a drum or bottle, it enters the environment. This release does not always lead to exposure. You are exposed to a substance only when you come in contact with it. You may be exposed by breathing, eating, or drinking the substance, or by skin contact. If you are exposed to pentachlorophenol, many factors determine whether you'll be harmed. These factors include the dose (how much), the duration (how long), and how you come in contact with it. You must also consider the other chemicals you're exposed to and your age, sex, diet, family traits, lifestyle, and state of health.

What is pentachlorophenol?


Pentachlorophenol is a synthetic substance, made from other chemicals, and does not occur naturally in the environment. It is made by only one company in the United States. At one time, it was one of the most widely used biocides in the United States. Since 1984, the purchase and use of pentachlorophenol has been restricted to certified applicators. It is no longer available to the general public. Application of pentachlorophenol in the home as an herbicide and pesticide accounted for only 3% of its consumption in the 1970s. Before use restrictions, pentachlorophenol was widely used as a wood preservative. It is now used industrially as a wood preservative for power line poles, cross arms, fence posts, and the like. Pure pentachlorophenol exists as colorless crystals. It has a very sharp characteristic phenolic smell when hot but very little odor at room temperature. Most people can begin to smell pentachlorophenol in water at less than 12 parts pentachlorophenol per million parts of water (ppm). Impure pentachlorophenol (the form usually found at hazardous waste sites) is dark gray to brown and exists as dust, beads, or flakes. Pentachlorophenol can be found in two forms: pentachlorophenol itself or as the sodium salt of pentachlorophenol. The sodium salt dissolves easily in water, but pentachlorophenol does not. These two forms have some different physical properties, but are expected to have similar toxic effects. Humans are generally exposed to technical-grade pentachlorophenol, which usually contains such toxic impurities as polychlorinated dibenzo- p-dioxins and dibenzofurans. Table 3-2 lists the impurities found in three different grades of pentachlorophenol.

What happens to pentachlorophenol when it enters the environment?


Pentachlorophenol is released to the air by evaporation from treated wood surfaces and factory (chemical manufacturing plants and wood preservation plants) waste disposal. It enters surface water and groundwater from factories, wood-treatment facilities, and hazardous waste sites. It also enters the soil as a result of spills, disposal at hazardous waste sites, and its use as a pesticide. The physical and chemical properties of the compound suggest that not much will evaporate into the atmosphere and that most of it will move with water and generally stick to soil particles. Movement of pentachlorophenol in soils depends on the soil's acidity. The compound can be present in fish or other species used for food, as demonstrated by the ongoing food monitoring program of the Food and Drug Administration (FDA). In air, soil, and surface water, pentachlorophenol lasts for hours to days. The compound is broken down in soil and surface water by microorganisms, and in air and surface water by sunlight, to other compounds, some of which may be harmful to humans.

More information on the releases, occurrence, and movement of pentachlorophenol in the environment can be found in Chapters 5 and 6 of the toxicological profile.


How might I be exposed to pentachlorophenol?


In addition to workplace exposures, humans can be exposed to very low levels of pentachlorophenol through indoor and outdoor air, food, soil, and drinking water. Exposure may also result from dermal contact with wood treated with preservatives that contain pentachlorophenol. Levels in the workplace, near certain hazardous waste sites, and near sites of accidental spills are usually higher than in the general environment. Exposure to pentachlorophenol by eating contaminated food is limited. The average intake in food is estimated to be 0.0105 milligrams of pentachlorophenol for a 70 kg human. Daily intake by drinking contaminated water is also low and is estimated to be about 0.021 mg for a 70 kg human. In its survey of various population groups in 1986�1991, the ongoing food monitoring program of the FDA observed a substantial decrease in the daily intakes of pentachlorophenol.

We do not have much information on the levels of pentachlorophenol in indoor and outdoor air, but the general population is estimated to breathe in about 0.063 mg/day. People who work or live near pentachlorophenol sources are exposed to higher levels. A 1984 report cites the measured concentration of pentachlorophenol in the indoor air of pressure-treated log homes brushed with pentachlorophenol in the range of 0.5�10 parts per trillion (ppt, 1 ppt is 1 million times less than 1 ppm) and in the air of industrially dipped, nonpressure-treated log homes at 34�104 ppt. Levels of pentachlorophenol in the air at wood-treatment facilities and lumber mills are much higher, and workers exposed at these places are estimated to breathe in 10.5�154.0 mg/day. Workers who handle treated lumber can take in about 35.0 mg/day through the skin.

For more information on exposure to pentachlorophenol, see Chapter 6 of the toxicological profile.

1.4 How can pentachlorophenol enter and leave my body?


Pentachlorophenol easily enters your body through your lungs when you breathe it, through your digestive tract after you eat contaminated food or water, or through your skin. The most significant ways are through breathing and skin contact. After a short exposure period, pentachlorophenol quickly leaves your body (studies in humans show that half the amount taken in is usually gone within 33 hours). It does not seem to build up in the body very much. Most of the pentachlorophenol taken into your body does not break down, but instead leaves in your urine. Much smaller amounts leave in your feces. Only a small amount escapes through your exhaled air. Some of the pentachlorophenol taken into your body is joined with other natural chemicals that make the pentachlorophenol less harmful. The combined product can then leave your body more easily.

Chapter 3 of the toxicological profile contains more information on how pentachlorophenol enters and leaves your body.

1.5 How can pentachlorophenol affect my health?


To protect the public from the harmful effects of toxic chemicals and to find ways to treat people who have been harmed, scientists use many tests.

To protect the public from the harmful effects of toxic chemicals and to find ways to treat people who have been harmed, scientists use many tests. One way to see if a chemical will hurt people is to learn how the chemical is absorbed, used, and released by the body; for some chemicals, animal testing may be necessary. Animal testing may also be used to identify health effects such as cancer or birth defects. Without laboratory animals, scientists would lose a basic method to get information needed to make wise decisions to protect public health. Scientists have the responsibility to treat research animals with care and compassion. Laws today protect the welfare of research animals, and scientists must comply with strict animal care guidelines.


Some, but not all, of the harmful effects associated with exposure to pentachlorophenol are due to impurities present in commercial pentachlorophenol. Short exposures to large amounts of pentachlorophenol in the workplace or through the misuse of products that contain it can cause harmful effects on the liver, kidneys, blood, lungs, nervous system, immune system, and gastrointestinal tract. Contact with pentachlorophenol (particularly in the form of a hot vapor) can irritate the skin, eyes, and mouth. If large enough amounts enter the body, heat is produced by the cells in the body, causing an increase in body temperature. The body temperature can increase to dangerous levels, causing injury to various organs and tissues and even death. This effect is the result of exposure to pentachlorophenol itself and not the impurities. The lengths of exposure and the levels that cause harmful effects have not been well defined. Long-term exposure to low levels such as those that occur in the workplace can cause damage to the liver, kidneys, blood, and nervous system. Studies in animals also suggest that the endocrine system and immune system can also be damaged following long-term exposure to low levels of pentachlorophenol. All of these effects get worse as the level of exposure increases. Decreases in the number of newborn animals, harmful effects on reproductive organs of the mothers, decreases in the number of successful pregnancies, and increases in the length of pregnancy were observed in animals exposed to pentachlorophenol while they were pregnant. Harmful effects on reproductive organs of the females were also seen in animals exposed to pentachlorophenol while they were not pregnant. We do not know if pentachlorophenol produces all of the same effects in humans that it causes in animals.


An increased risk of cancer has been shown in some laboratory animals given large amounts of pentachlorophenol orally for a long time. There is weak evidence that pentachlorophenol causes cancer in humans. The International Agency for Research on Cancer (IARC) has determined that pentachlorophenol is possibly carcinogenic to humans, and the EPA has classified pentachlorophenol as a probable human carcinogen.


Chapters 2 and 3 of the toxicological profile contain more information on the health effects linked with exposure to pentachlorophenol.

How can pentachlorophenol affect children?


Children might be exposed to pentachlorophenol by eating fish and other foods contaminated with the substance, by accidentally or intentionally eating soil or drinking water contaminated with the substance, or by drinking breast milk contaminated with the substance. Tests have not been performed to measure pentachlorophenol in breast milk in the United States, although small amounts have been found in the milk of chemical workers in Eastern Europe. Children might also be exposed to pentachlorophenol by breathing air in homes that contain wood that has been treated with the substance or by skin contact with contaminated soils or with the exposed surface of wood that has been treated with the substance. For most people, food is the most important source of intake of pentachlorophenol, and most of this intake is from root vegetables. Based on analyses of foods representative of the diets of different age/gender population groups, daily intakes of pentachlorophenol from the diet, although low overall, are higher in infants and toddlers than in teenagers and adults. Daily intakes of pentachlorophenol from food have decreased over time.


Newborn children who were accidentally exposed to diapers and bedding that were contaminated with pentachlorophenol had high fevers, a large amount of sweating, a hard time with breathing, and harmful effects on their nervous system and liver, and some died. In the newborn animals of mothers that were given pentachlorophenol by mouth, slight changes were seen in the formation of bones and their weight was decreased at weaning. One study in animals showed that large amounts of pentachlorophenol taken by mouth can damage the testes, but it is unknown whether such large amounts affect the ability of animals to have babies. The immune system was suppressed in family members, including children as young as 8 years old, who were exposed to pentachlorophenol while living in log homes.


Absorption of pentachlorophenol is expected by all routes of exposure, and the harmful effects of pentachlorophenol should be qualitatively similar over all routes of exposure; these effects might also occur in children exposed to low levels of pentachlorophenol by any route. There is not enough information to know whether children under 18 years of age differ from adults in their sensitivity to the health effects of pentachlorophenol. One study in animals found that small amounts of pentachlorophenol may cross the placenta, and it is possible that it can reach and cross the placenta in humans.

How can families reduce the risk of exposure to pentachlorophenol?


If your doctor finds that you have been exposed to significant amounts of pentachlorophenol, ask whether your children might also be exposed. Your doctor might need to ask your state health department to investigate.

Pentachlorophenol was a widely used pesticide and a wood preservative (utility poles) for a long time. It is no longer present in any product you can buy today. It can be applied only by certified applicators. Although it is no longer commonly used, traces of pentachlorophenol are still found in small amounts in air, water, and soil. It is also found at some hazardous waste sites. Up until 1980, you could buy pentachlorophenol-containing pesticides. Since then, it has been regulated and can only be used in a restricted number of places. You may have old containers of pesticides in your attic, basement, or garage that contain pentachlorophenol. Removing these old containers will reduce your family's risk of exposure to pentachlorophenol. You should dispose of these old containers in an appropriate manner through your county's hazardous waste facility. Otherwise, place them out of reach of young children to prevent accidental exposures. You should never store pesticides or household chemicals in containers that children would find attractive to eat or drink from, such as soda bottles.

Your children may be exposed to pentachlorophenol if an unqualified person applies pesticides containing it around your home. In some cases, the improper use of pesticides banned for use in homes has turned homes into hazardous waste sites. Make sure that any person you hire is licensed and, if appropriate, certified to apply pesticides. Your state licenses each person who is qualified to apply pesticides according to EPA standards and further certifies each person who is qualified to apply "restricted use" pesticides. Ask to see the license and certification. Also ask for the brand name of the pesticide, a Material Safety Data Sheet (MSDS), the name of the product's active ingredient, and the EPA registration number. Ask whether EPA has designated the pesticide "for restricted use" and what the approved uses are. This information is important if you or your family react to the product.


Though pentachlorophenol has been found in some foods, its levels are low. You can minimize the risk of your family's exposure by peeling and thoroughly washing fruits and vegetables before cooking.


Small children have a tendency to eat soil, and to put their hands and foreign objects in their mouths. This could result in their exposure to pentachlorophenol that may be present in the soil and on objects. Children may be exposed to pentachlorophenol by absorption through the skin. Pentachlorophenol is known to be rapidly absorbed by the skin from the soil. You should prevent children from putting their hands and foreign objects in their mouths and you should discourage your children from eating dirt. Make sure they wash their hands frequently. Very low levels of pentachlorophenol have been detected in house and carpet dust. Keeping the house clean and free of dust will reduce your family's exposure to pentachlorophenol.


Pentachlorophenol was used for treating wood. It is no longer used for treating wood used in and around homes. But it is still used for treating wood utility poles and railroad ties. If you live near a utility pole or railroad tracks, you should prevent your children from playing, climbing, or sitting on them especially in the hot summer months. Old playground equipment may contain pentachlorophenol, and children may be exposed dermally when playing on it. If you have old treated wood in or around your house, covering it with epoxy paint may reduce the risk of your family's exposure to pentachlorophenol. Wood treated with pentachlorophenol (e.g., railway ties) should not be used for landscaping, especially near gardens or private wells





Use Composite Poles







Use Composite Poles


https://infohouse.p2ric.org/ref/34/33287.pdf (Cost and Sites - CLEANUP) 












Site maintained by: www.LongIslandBuilders.com