1.1 What is radium? |
1.2 How might I be exposed to radium? |
1.3 How can radium enter and leave my
body? |
1.4 How can radium affect my health? |
1.5 What levels of exposure have resulted
in harmful health effects? |
1.6 Is there a medical test to determine
whether I have been exposed to radium? |
1.7 What recommendations has the federal
government made to protect human health? |
1.8 Where can I get more information? |
References |
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December 1990 |
Public Health Statement |
for |
Radium |
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This Public Health Statement is the
summary chapter from the Toxicological
Profile for radium. 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, call the ATSDR Information
Center at 1-888-422-8737.
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This Statement was prepared to give you
information about radium and to emphasize the human health
effects that may result from exposure to it. The Environmental
Protection Agency (EPA) has identified 1,177 sites on its
National Priorities List (NPL). Radium has been found above
background levels at 18 of these sites. However, we do not
know how many of the 1,177 NPL sites have been evaluated for
radium. As EPA evaluates more sites, the number of sites at
which radium is found above background levels may change.
The information is important for you because radium may cause
harmful health effects and because these sites are potential
or actual sources of human exposure to radium.
When a radioactive chemical 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
as a radioactive chemical emission. This emission, which is
also called a release, does not always lead to exposure. You
can be exposed to a radioactive chemical when you come into
contact with that chemical alone or with a substance that
contains it. You may be exposed to it in the environment by
breathing, eating, or drinking substances containing the radioactive
chemical or from skin contact with it. Exposure can also occur
by being near radioactive chemicals at concentrations that
are found at hazardous waste sites or industrial accidents.
If you are exposed to a hazardous substance
such as radium, several factors will determine whether harmful
health effects will occur and what the type and severity of
those health effects will be. These factors include the dose
(how much), the duration (how long), the route or pathway
by which you are exposed (breathing, eating, drinking, or
skin contact), the other chemicals to which you are exposed,
and your individual characteristics such as age, sex, nutritional
status, family traits, life style, and state of health.
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1.1
What is radium? |
Radium is a naturally-occurring silvery
white radioactive metal that can exist in several forms called
isotopes. It is formed when uranium and thorium (two other
natural radioactive substances) decay (break down) in the
environment. Radium has been found at very low levels in soil,
water, rocks, coal, plants, and food. For example, a typical
amount might be one picogram of radium per gram of soil or
rock. This would be about one part of radium in one
trillion (1,000,000,000,000) parts of soil or rock. These
levels are not expected to change with time.
Some of the radiation from radium is
constantly being released into the environment. It is this
release of radiation that causes concern about the safety
of radium and all other radioactive substances. Each isotope
of radium releases radiation at its own rate. One isotope,
radium-224 for example, releases half of its radiation in
about three and a half days; whereas another isotope, radium-226,
releases half of its radiation in about 1,600 years.
When radium decays it divides into two
parts. One part is called radiation, and the second part is
called a daughter. The daughter, like radium, is not stable;
and it also divides into radiation and another daughter. The
dividing continues until a stable, nonradioactive daughter
is formed. During the decay process, alpha, beta, and gamma
radiations are released. Alpha particles can travel only a
short distance and cannot travel through your skin. Beta particles
can penetrate through your skin, but they cannot go all the
way through your body. Gamma radiation, however, can go all
the way through your body. Thus, there are several types of
decay products that result from radium decay.
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1.2
How might I be exposed to radium? |
Because radium is present, usually at
very low levels, in the surrounding environment, you are always
exposed to it and to the small amounts of radiation that it
releases to its surroundings. You may be exposed to higher
levels of radium if you live in an area where it is released
into the air from the burning of coal or other fuels, or if
your drinking water is taken from a source that is high in
natural radium, such as a deep well, or from a source near
a radioactive waste disposal site.
Levels of radium in public drinking water
are usually less than one picocurie per liter of water (about
one quart), although higher levels (more than 5 picocuries
per liter) have been found. A picocurie (pCi) is a very small
amount of radioactivity, and it is associated with about a
trillionth of a gram (a picogram) of radium. (There are approximately
28 grams in an ounce.) No information is available about the
amounts of radium that are generally present in food and air.
You may also be exposed to higher levels of radium if you
work in a uranium mine or in a plant that processes uranium
ores.
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1.3
How can radium enter and leave my body? |
Radium can enter the body when it is
breathed in or swallowed. It is not known if it can be taken
in through the skin. If you breathe radium into your lungs,
some may remain there for months; but it will gradually enter
the blood stream and be carried to all parts of the body,
especially the bones.
For months after exposure, very small
amounts leave the body daily through the feces and urine.
If radium is swallowed in water or with food, most of it (about
80%) will promptly leave the body in the feces. The other
20% will enter the blood stream and be carried to all parts
of the body, especially the bones. Some of this radium will
then be excreted in the feces and urine on a daily basis.
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1.4
How can radium affect my health? |
There is no clear evidence that long-term
exposure to radium at the levels that are normally present
in the environment (for example, 1 pCi of radium per gram
of soil) is likely to result in harmful health effects. However,
exposure to higher levels of radium over a long period of
time may result in harmful effects including anemia, cataracts,
fractured teeth, cancer (especially bone cancer), and death.
Some of these effects may take years to develop and are mostly
due to gamma radiation. Radium gives off gamma radiation,
which can travel fairly long distances through air. Therefore,
just being near radium at the high levels that may be found
at some hazardous waste sites may be dangerous to your health.
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1.5
What levels of exposure have resulted in harmful health effects? |
Radium has been shown to cause adverse
health effects such as anemia, cataracts, fractured teeth,
cancer and death. The relationship between the amount of radium
that you are exposed to and the amount of time necessary to
produce these effects is not known. Although there is some
uncertainty as to how much exposure to radium increases your
chances of developing a harmful health effect, the greater
the total amount of your exposure to radium, the more likely
you are to develop one of these diseases.
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1.6
Is there a medical test to determine whether I have been exposed
to radium? |
There are few medical tests to determine
if you have been exposed to radium. There is a urine test
to determine if you have been exposed to a source of radioactivity
such as radium. There is also a test to measure the amount
of radon, a breakdown product of radium, when it is exhaled.
These tests require special equipment and cannot be done in
a doctor's office. Another test can measure the total amount
of radioactivity in the body; however, this test is not used
except in special cases of high exposure.
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1.7
What recommendations has the federal government made to protect
human health? |
The EPA has set a drinking water limit
of 5 picocuries per liter (5 pCi/L) for radium-226 and radium-228
(combined).
The EPA has set a soil concentration
limit for radium-226 in uranium and thorium mill tailings
of 5 picocuries per gram in the first 15 centimeters of soil
and 15 picocuries per gram in deeper soil.
The federal recommendations have been
updated as of July 1999.
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1.8 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 F-32
Atlanta, GA 30333
Information line and technical assistance:
Phone: 888-422-8737
FAX: (770)-488-4178
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: 800-553-6847 or 703-605-6000
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References |
Agency for Toxic Substances and Disease
Registry (ATSDR). 1990. Toxicological
profile for radium. Atlanta, GA: U.S. Department of Health
and Human Services, Public Health Service.
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