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The following information is derived from the DOE
Training Reference for Beryllium Workers and Managers/Supervisors
Participant Manual entitled, Communicating
Health Risks, Working Safely With Beryllium, May
1998. Student
information - Encyclopedia article, similar to
below, describing the properties, occurrence, and
uses of beryllium.
Beryllium Is a Silver-Gray Metallic Element That Occurs
Naturally in About 30 Minerals
Beryllium was discovered in 1798, but it was not
widely used in industry until the 1940s and 1950s.
In industrial applications beryllium can be:
- used as pure metal
- mixed with other metals to form alloys
- processed to salts that dissolve in water
- processed to form oxides and ceramic materials
Beryllium-Containing Minerals Are Found in Rocks,
Coal and Oil, Soil, and Volcanic Dust
From these sources, beryllium is emitted into the
air and water by natural processes like erosion and
by the burning of coal and oil. According to data
collected by the Environmental Protection Agency (EPA),
the average concentration of airborne beryllium in
the U.S. is very small (0.03 nanogram/cubic
meter—a nanogram is one-billionth of a gram).
Beryllium used in industry begins as a silicate (BeSiO3)
in beryl and bertrandite ores. In a very pure crystalline
form, beryl is known to us as gems such as blue-green
aquamarine and green emerald.
Bertrandite is mined in Utah, but other ores and
scrap are imported into the U.S., which is
the world’s leading producer, processor, and consumer
of beryllium products. According to U.S. Geological
Survey reports, total US use of all forms of beryllium
in 1996 was about 234 metric tons.
| Lighter than Aluminum, Stiffer than
Steel-Properties That Make Beryllium Useful |
| Light weight |
- atomic weight is 9.0122
- second lightest of the metals, only 1/3
as heavy as aluminum
- density of 1.85 grams per cubic centimeter
is similar to magnesium, and 2/3 that of aluminum
|
| Stiffness or rigidity |
- about 6 times stiffer than steel
- can withstand great force before bending
|
| High melting point |
- (1285 C) compared to other light metals
- holds its shape over a wide temperature
range
|
| High heat-absorption capacity |
- a pound will absorb as much heat as 5 pounds
of copper
|
| Nonmagnetic |
| Dimensional stability |
| Good corrosion resistance |
| Lowest thermal neutron absorption
cross-section of any metal |
| High permeability (transparency)
to X-rays |
| Can be machined to close tolerances |
Many Products and Processes Use Beryllium's Properties
Beryllium metal has been produced for various industrial
uses since the late 1950s.
Both structural and instrument grade materials are
manufactured, especially for use in aerospace and
defense:
- Windshield frames and other structures in high-speed
aircraft and space vehicles
- Aircraft and space shuttle brakes
- Satellite mirrors and space telescopes
- Inertial guidance systems and gyroscopes
- Neutron moderator or reflector in nuclear reactors
- X-ray windows
- Nuclear weapons components
Other Beryllium Materials Include Soluble Salts, Alloys,
and Oxide
Soluble salts, such as beryllium fluoride,
chloride, and sulfate, are used in nuclear reactors,
in glass manufacture, and as catalysts for certain
chemical reactions.
Beryllium-copper (BeCu) alloys usually contain
about 2 percent beryllium, but vary greatly in composition
to meet different industrial and consumer needs. Beryllium
contributes hardness, strength, high electrical and
thermal conductivity, and resistance to corrosion,
wear, and fatigue. For example, BeCu springs "bounce
back" to their original shape again and again.
Be alloys are used for:
- Springs, switches, relays, and connectors in automobiles,
computers, radar and telecommunications equipment,
and other instruments
- High-strength nonsparking tools including some
tools sold for use in the home
- Molds or casts to make metal, glass, and plastic
items
- Sports equipment such as golf clubs and bicycle
frames
- Dental bridges and related applications
Beryllium is also added to aluminum, nickel, zinc,
and zirconium for some applications. Beryllium-nickel
alloys are used in automobile air bags. A relatively
new beryllium-aluminum alloy (the registered trademark
is "Beralcast") is being used in fighter planes, helicopters,
and missile systems.
Beryllium Oxide (BeO) Is Used To Make Ceramics for
Electronics, Electrical, and Other Equipment
BeO contributes hardness, strength, excellent heat
conductivity, and good electrical insulation. In closely
packed circuitry (like that in the electronic ignition
systems of automobiles), beryllium ceramic layers
can draw heat away from other circuit components.
Because BeO is transparent to microwaves, it has also
been used in microwave ovens.
Despite its Usefulness, Beryllium Is Not an Ideal
Material
It is expensive and too brittle to work with in some
applications.
The most significant disadvantage of beryllium
as an industrial material is the toxicity of its dust,
fumes, and soluble salts.
Beryllium's brittleness is the down side of its advantageous
stiffness. Brittleness also increases the hazards
associated with beryllium's toxicity. Unless ventilation
and other controls are used, small particles and chips
of insoluble beryllium-containing materials break
off during machining and other processes and spread
through the air in the work area. Inhalation of these
tiny particles is the type of exposure that can lead
to chronic beryllium disease.
Beryllium Is a Significant Workplace Health Hazard
Exposure to beryllium particles can cause a serious
illness in certain people. This illness is chronic
beryllium disease, or CBD-an irreversible and sometimes
fatal scarring of the lungs.
- Medical studies show that even small amounts of
beryllium particles of a size that can be breathed
deeply into the lungs may trigger an allergy-like
sensitivity in 2-5 percent of people exposed.
- About 1 to 3 percent of all people exposed to
beryllium develop CBD. In studies of people in certain
occupations where historically exposure to beryllium
was greatest (for example, studies of machinists
in beryllium operations), this number rises to as
many as 10 to 14 percent.
- There is currently no widely available test to
find out who is sensitive to beryllium before
exposure occurs.
- More than 100 current and former employees of
Department of Energy (DOE) sites have CBD. The percentage
of people who were exposed and became ill is much
larger than similar percentages known for other
DOE workplace health hazards.
CBD is seen only in individuals who have experienced
some exposure to beryllium particles, dust, or fumes.
Chronic Beryllium Disease: A Long-Term Health Effect
Long-term, or chronic, health effects can
take years to develop after the first exposure to
beryllium and can affect people who were exposed to
very small amounts of beryllium. In some cases, CBD
has been diagnosed in former office workers and others
who had only brief, incidental exposure to beryllium.
CBD is primarily a lung disease, but it may also
affect other organs, particularly the lymph nodes,
skin, spleen, liver, kidneys, and heart.
CBD is seen in individuals who are sensitized
to beryllium.
CBD occurs in individuals who have become "allergic"
or sensitized to beryllium upon exposure. Although
current DOE medical surveillance programs are identifying
more people who are only sensitized and not sick with
CBD, many individuals already have CBD by the time
they are evaluated for beryllium sensitization or
lung symptoms.
CBD can take many years to develop.
The average time from first beryllium exposure to
the development of symptoms (latency period)
of CBD is 10 to 15 years. This means you can be exposed
to beryllium today and not suffer any health effects
for decades. Health effects have appeared in some
people a few months after exposure, but not for as
long as 30 years in others.
Doctors and researchers believe that some individuals
who have had CBD lived with the disease and died from
other causes without even knowing they had CBD.
CBD symptoms resemble those of other lung diseases.
The symptoms of CBD are very similar to those of
several other diseases, particularly a disease called
sarcoidosis that affects the lungs and sometimes
other organs. Studies have found that in some cases
doctors have diagnosed what turned out to be CBD as
sarcoidosis or another disease.
Symptoms of CBD may include the following:
- Persistent coughing
- Shortness of breath with physical exertion
- Fatigue
- Chest and joint pain
- Blood in the sputum (sputum is saliva,
mucus, and other discharges that can be "coughed
up" from the respiratory system)
- Rapid heart rate
- Loss of appetite
- Fevers and night sweats
CBD is treatable, but not curable.
If loss of lung function is detected, treatment may
involve taking corticosteroids (often just called
"steroids"), a medicine that reduces inflammation.
The most common type of corticosteroid prescribed
for CBD is prednisone. If successful, treatment with
steroids can slow the progress of CBD by reducing
the buildup of scar tissue and delaying permanent
lung damage.
However, many individuals do not respond well to
treatment. Others cannot tolerate the side effects
of long-term steroid treatment. Side effects of taking
steroids for long periods of time can include slower
healing of infections, calcium loss from the bones,
higher blood cholesterol, and fluid and salt retention
which can make heart or kidney disease worse. The
right treatment for an individual must be considered
in light of that person's overall health and medical
history.
Individuals with insufficient levels of oxygen in
their blood as a result of CBD may also need supplemental
oxygen to help improve oxygen delivery to the body
and to protect the heart from the damage that can
be done by low oxygen levels.
Individuals who cannot take steroids may continue
to lose lung function. As a result they are likely
to experience poorer quality of life, becoming invalids
in some cases. Their life span may also be shorter.
Although the use of corticosteroids is the standard
treatment for CBD, research is in progress on other
drugs that may reduce the need for high doses of corticosteroids.
On the other hand, some individuals with diagnosed
CBD may never become sick enough to require treatment.
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