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.
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.
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.
** 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.
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.
SEPTEMBER 1994
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.
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.
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.
This wood has been preserved by pressure-treatment with anEPA-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.
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.
Chlor-acne:
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.
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.
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.
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.
• 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.
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
