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"Draft for Public Comment"
Public Health Statement for
Copper
CAS#
7440-50-8
September 2002
This Public Health Statement is the summary chapter from the Toxicological
Profile for Copper. It is one in a series of Public Health Statements
about hazardous substances and their health effects. A shorter version,
the ToxFAQs™, 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,
you may call the ATSDR Information Center at 1-888-422-8737.
This public health statement tells you about copper 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. Copper has been found in at least 884 of the 1,613
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 copper 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 copper, many factors determine whether you’ll be
harmed. These factors include the dose (how much), the duration (how long),
and the route of exposure (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.
1.1 What is copper?
Copper is a reddish metal that occurs naturally in rock, soil, water,
sediment, and, at low levels, air. Its average concentration in the earth’s
crust is about 50 parts copper per million parts soil (ppm) or, stated
another way, 50 grams of copper per 1,000,000 grams of soil. Copper also
occurs naturally in all plants and animals. It is an essential element
for all known living organisms including humans and other animals at low
levels of intake. At much higher levels, some toxic effects can occur.
Metallic copper can be easily molded or shaped. The reddish color of
this element is most commonly seen in the U.S. penny, electrical wiring,
and some water pipes. It is also found in many mixtures of metals, called
alloys, such as brass and bronze. Many compounds (substances formed by
joining two or more chemicals) of copper exist. These include naturally
occurring minerals as well as manufactured chemicals. The most commonly
used compound of copper is copper sulfate. Many copper compounds can be
recognized by their blue-green color. When we speak of copper, we will
not only be referring to copper metal, but also to compounds of copper
that may be in the environment.
Copper is extensively mined and processed in the United States and is
primarily used as the metal or alloy in the manufacture of wire, sheet
metal, pipe, and other metal products. Copper compounds are most commonly
used in agriculture to treat plant diseases, like mildew, or for water
treatment and as preservatives for wood, leather, and fabrics. For more
information on the properties and uses of copper, please see Chapters
4 and 5.
1.2 What happens to copper when it enters the environment?
Copper can enter the environment through releases from the mining of
copper and other metals, and from factories that make or use copper metal
or copper compounds. Copper can also enter the environment through domestic
waste water, combustion of fossil fuels and wastes, wood production, phosphate
fertilizer production, and natural sources (for example, windblown dust,
from native soils, volcanoes, decaying vegetation, forest fires, and sea
spray). Therefore, copper is widespread in the environment. About 1,400,000,000
pounds of copper were released into the environment by industries in 2000.
Copper is often found near mines, smelters, industrial settings, landfills,
and waste disposal sites.
When copper is released into soil, it typically becomes strongly attached
to the organic material and minerals in the top layers of soil and does
not move very far when it is released. When copper is released into water,
the copper that dissolves can be carried in surface waters either as free
copper or, more likely, bound to particles suspended in the water. Because
copper binds so strongly to suspended particles and sediments, it typically
does not enter groundwater. Copper that enters water eventually collects
in the sediments of rivers, lakes, and estuaries. Copper is carried on
particles emitted from smelters and ore processing plants, and is then
carried back to earth through gravity or in rain or snow. Copper is also
carried into the air on windblown metallurgical dust. Indoor release of
copper comes mainly from combustion processes (for example, kerosene heaters).
Copper does not break down in the environment. Copper can be found in
plants and animals, and at high concentrations in mussels and oysters.
Copper is also found in a range of concentrations in many foods and beverages
that we eat and drink, including drinking water. You will find additional
information on the fate of copper in the environment in Chapters 5 and
6.
1.3 How might I be exposed to copper?
Copper is common in the environment. You may be exposed to copper by
breathing air, drinking water, eating food, and by skin contact with soil,
water, and other copper-containing substances. Most copper compounds found
in air, water, sediment, soil, and rock are so strongly attached to dust
and dirt or imbedded in minerals. However, you can still be exposed to
copper upon ingestion of water or soil that contains copper or, to a lesser
extent, by inhalation of copper-containing dust. Some copper in the environment
is less tightly bound to particles and may be taken up by plants and animals.
Soluble copper compounds (those that dissolve in water), which are most
commonly used in agriculture, are more likely to threaten your health.
When soluble copper compounds are released into lakes and rivers, they
generally become attached to particles in the water within approximately
1 day. This could lessen your exposure to copper in water, depending on
how strongly the copper is bound to the particles and how much of the
particles settle into lake and river sediments.
The concentration of copper in air ranges from a few nanograms (1 nanogram
equals 1/1,000,000,000 of a gram) in a cubic meter of air (ng/m3) to about
200 ng/m3. Near smelters, which process copper ore into metal, concentrations
may reach 5,000 ng/m3. You may breathe high levels of copper-containing
dust if you live or work near copper mines or processing facilities.
You may be exposed to high levels of soluble copper in your drinking
water, especially if your water is corrosive and you have copper plumbing
and brass water fixtures. The average concentration of copper in tap water
ranges from 20 to 75 parts copper per billion parts water (ppb). However,
many households have copper concentrations of over 1,000 ppb. That is
more than 1 milligram per liter of water. This is because copper is picked
up from copper pipes and brass faucets when the water sits in the pipes
overnight. After the water is allowed to run for 15-30 seconds, the concentration
of copper in the water decreases.
The average concentration of copper in lakes and rivers is 4 ppb. The
average copper concentration in groundwater is similar to that in lakes
and rivers; however, monitoring data indicate that some groundwater contains
higher levels of copper. This copper is generally strongly attached to
particles in the water. Lakes and reservoirs recently treated with copper
compounds to control algae or receive cooling water from a power plant
may have high concentrations of dissolved copper. Once in natural water,
much of this copper soon attaches to particles or converts to forms that
can settle into sediments. This can limit exposure to copper unless the
sediments are stirred; for example, by the resuspension and swallowing
of sediments by swimmers in recreational waters.
Garden products containing copper that are used to control certain plant
diseases are also a potential source of exposure. For example, you can
find copper compounds in some fungicides.
Soil generally contains between 2 and 250 ppm copper, although concentrations
close to 17,000 ppm have been found near copper and brass production facilities.
High concentrations of copper may be found in soil because dust from these
industries settles out of the air, or wastes from mining and other copper
industries are disposed of on the soil. Another common source of copper
in soil results from spreading sludge from sewage treatment plants. This
copper generally stays strongly attached to the surface layer of soil.
You may be exposed to this copper by skin contact. Children may also be
exposed to this copper by eating the dirt and dust generated therefrom.
Food naturally contains copper. You eat and drink about 1 milligram (1/1,000
of a gram) of copper every day. Copper is essential in your diet for good
health.
While some hazardous waste sites on the NPL contain high levels of copper,
we do not always know how high it is above natural levels. We also do
not know what form it is in at most of these sites. However, evidence
suggests that most copper at these sites is strongly attached to soil.
You may be exposed to copper in the workplace. If you work in the industry
of mining copper or processing the ore, you are exposed to copper by breathing
copper-containing dust or by skin contact. If you grind or weld copper
metal, you may breathe high levels of copper dust and fumes. Occupational
exposure to forms of copper that are soluble or not strongly attached
to dust or dirt would most commonly occur in agriculture, water treatment,
and industries such as electroplating, where soluble copper compounds
are used.
For more information on the potential for exposure to copper, please
refer to Chapter 6.
1.4 How can copper enter and leave my body?
Copper can enter your body when you drink water or eat food, soil, or
other substances that contain copper. Copper can also enter your body
if you breathe air or dust containing copper. Copper may enter the lungs
of workers exposed to copper dust or fumes.
Copper rapidly enters the bloodstream and is distributed throughout the
body after you eat or drink it. Other foods eaten with copper can affect
the amount of copper that enters the bloodstream. Your body is very good
at blocking high levels of copper from entering the bloodstream. We do
not know how much copper enters the body through the lungs or skin. Copper
then leaves your body in feces and urine, mostly in feces. It takes several
days for copper to leave your body. Generally, the amount of copper in
your body remains constant (the amount that enters your body equals the
amount that leaves). More information on how copper enters and leaves
the body is presented in Chapter 3.
1.5 How can copper 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.
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.
Copper is essential for good health. However, exposure to higher doses
can be harmful. Long-term exposure to copper dust can irritate your nose,
mouth, and eyes, and cause headaches, dizziness, nausea, and diarrhea.
If you drink water that contains higher than normal levels of copper,
you may experience vomiting, diarrhea, stomach cramps, and nausea. Intentionally
high intakes of copper can cause liver and kidney damage and even death.
We do not know if copper can cause cancer in humans. EPA has determined
that copper is not classifiable as to human carcinogenicity.
More detailed information on the health effects of copper in animals
and humans can be found in Chapter 3.
1.6 How can copper affect children?
This section discusses potential health effects from exposures during
the period from conception to maturity at 18 years of age in humans.
Exposure to high levels of copper will result in the same types of effects
in children and adults. We do not know if children are more susceptible
to the toxicity of copper than adults. Studies in animals suggest that
children may have more severe effects than adults; we do not know if this
would also be true in humans. There is a very small percentage of infants
and children who are unusually sensitive to copper. We do not know if
copper can cause birth defects or other developmental effects in humans.
Studies in animals suggest that ingestion of high levels of copper may
cause a decrease in fetal growth.
1.7 How can families reduce the risk of exposure to copper?
If your doctor finds that you have been exposed to significant amounts
of copper, ask whether your children might also be exposed. Your doctor
might need to ask your state health department to investigate. The greatest
potential source of copper exposure is through drinking water, especially
in water that is first drawn in the morning after sitting in copper piping
and brass faucets overnight. To reduce copper in drinking water, run the
water for at least 15-30 seconds before using it.
1.8 Is there a medical test to determine whether i have been exposed
to copper?
Copper is normally found in all tissues of the body, blood, urine, feces,
hair, and nails. High levels of copper in the blood, urine, hair, and
nails can show that you have been exposed to higher than normal levels
of copper. Tests to measure copper levels in the body are not usually
available at a doctor’s office because they require special equipment.
Although these tests can show that you have been exposed to higher than
normal copper levels, they can not be used to predict the extent of exposure
or potential health effects. More detailed information on the measurement
of copper is provided in Chapters 3 and 7.
1.9 What recommendations has the federal government made to protect human
health?
The federal government develops regulations and recommendations to protect
public health. Regulations can be enforced by law. Federal agencies that
develop regulations for toxic substances include the Environmental Protection
Agency (EPA), the Occupational Safety and Health Administration (OSHA),
and the Food and Drug Administration (FDA). Recommendations provide valuable
guidelines to protect public health but cannot be enforced by law. Federal
organizations that develop recommendations for toxic substances include
the Agency for Toxic Substances and Disease Registry (ATSDR) and the National
Institute for Occupational Safety and Health (NIOSH).
Regulations and recommendations can be expressed in not-to-exceed levels
in air, water, soil, or food that are usually based on levels that affect
animals; then they are adjusted to help protect people. Sometimes these
not-to-exceed levels differ among federal organizations because of different
exposure times (an 8-hour workday or a 24-hour day), the use of different
animal studies, or other factors.
Recommendations and regulations are also periodically updated as more
information becomes available. For the most current information, check
with the federal agency or organization that provides it. Some regulations
and recommendations for copper include the following:
EPA has determined that drinking water should not contain more than 1.3
mg copper per liter of water (1.3 mg/L). EPA has developed regulations
on the amount of copper released by industry.
OSHA has set a limit of 0.1 milligrams/cubic meter (mg/m3) of copper
fumes (vapor generated from heating copper) and 1.0 mg/m3 of copper dusts
(fine metallic copper particles) and mists (aerosol of soluble copper)
in workroom air to protect workers during an 8-hour work shift (40-hour
workweek).
The Food and Nutrition Board of the Institute of Medicine has developed
recommended dietary allowances (RDAs) of 340 micrograms (µg) of
copper per day for children aged 1-3 years, 440 µg/day for children
aged 4-8 years, 700 µg/day for children aged 9-13 years, 890 µg/day
for children aged 14-18 years, and 900 µg/day for adults. This provides
enough copper to maintain health. Further information on regulations and
guidelines pertaining to copper is provided in Chapter 8.
1.10 Where can I get more information?
If you have any more questions or concerns, please contact your community
or state health or environmental quality department or
Agency for Toxic Substances and Disease Registry
Division of Toxicology
1600 Clifton Road NE, Mailstop E-29
Atlanta, GA 30333
Web site: http://www.atsdr.cdc.gov
* Information line and technical assistance
Phone: 1-888-42-ATSDR (1-888-422-8737)
Fax: 1-404-498-0057
ATSDR can also tell you the location of occupational and environmental
health clinics. These clinics specialize in recognizing, evaluating, and
treating illnesses resulting from exposure to hazardous substances.
* To order toxicological profiles, contact
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Phone: 1-800-553-6847 or 1-703-605-6000
References
Agency for Toxic Substances and Disease Registry (ATSDR). 2002. Toxicological
profile for copper - draft for public comment. Atlanta, GA: U.S. Department
of Health and Human Services, Public Health Service.
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