- What is asbestos?
Asbestos is the name given to a group of minerals that occur naturally in
the environment as bundles of fibers that can be separated into thin, durable
threads. These fibers are resistant to heat, fire, and chemicals and do not
conduct electricity. For these reasons, asbestos has been used widely in many
industries.
Chemically, asbestos minerals are silicate compounds, meaning they contain
atoms of silicon and oxygen in their molecular structure.
Asbestos minerals are divided into two major groups: Serpentine asbestos
and amphibole asbestos. Serpentine asbestos includes the mineral chrysotile,
which has long, curly fibers that can be woven. Chrysotile asbestos is the
form that has been used most widely in commercial applications. Amphibole
asbestos includes the minerals actinolite, tremolite, anthophyllite, crocidolite,
and amosite. Amphibole asbestos has straight, needle-like fibers that are
more brittle than those of serpentine asbestos and are more limited in their
ability to be fabricated (1, 2).
- How is asbestos used?
Asbestos has been mined and used commercially in North America since the
late 1800s. Its use increased greatly during World War II (3,
4). Since then, asbestos has been used in many industries.
For example, the building and construction industries have used it for strengthening
cement and plastics as well as for insulation, roofing, fireproofing, and
sound absorption. The shipbuilding industry has used asbestos to insulate
boilers, steam pipes, and hot water pipes. The automotive industry uses asbestos
in vehicle brake shoes and clutch pads. Asbestos has also been used in ceiling
and floor tiles; paints, coatings, and adhesives; and plastics. In addition,
asbestos has been found in vermiculite-containing garden products and some
talc-containing crayons.
In the late 1970s, the U.S. Consumer Product Safety Commission (CPSC) banned
the use of asbestos in wallboard patching compounds and gas fireplaces because
the asbestos fibers in these products could be released into the environment
during use. In addition, manufacturers of electric hairdryers voluntarily
stopped using asbestos in their products in 1979. In 1989, the U.S. Environmental
Protection Agency (EPA) banned all new uses of asbestos; however, uses developed
before 1989 are still allowed. The EPA also established regulations that require
school systems to inspect buildings for the presence of damaged asbestos and
to eliminate or reduce asbestos exposure to occupants by removing the asbestos
or encasing it (2).
In June 2000, the CPSC concluded that the risk of children’s exposure
to asbestos fibers in crayons was extremely low (1). However,
U.S. manufacturers of these crayons agreed to eliminate talc from their products.
In August 2000, the EPA conducted a series of tests to evaluate the risk
for consumers of adverse health effects associated with exposure to asbestos-contaminated
vermiculite. The EPA concluded that exposure to asbestos from some vermiculite
products poses only a minimal health risk. The EPA recommended that consumers
reduce the low risk associated with the occasional use of vermiculite during
gardening activities by limiting the amount of dust produced during vermiculite
use. Specifically, the EPA suggested that consumers use vermiculite outdoors
or in a well-ventilated area; keep vermiculite damp while using it; avoid
bringing dust from vermiculite into the home on clothing; and use premixed
potting soil, which is less likely to generate dust (2).
The regulations described above and other actions, coupled with widespread
public concern about the health hazards of asbestos, have resulted in a significant
annual decline in the U.S. use of asbestos. Domestic consumption of asbestos
amounted to about 803,000 metric tons in 1973, but it had dropped to about
2,400 metric tons by 2005 (3, 5).
- What are the health hazards of exposure
to asbestos?
People may be exposed to asbestos in their workplace, their communities,
or their homes. If products containing asbestos are disturbed, tiny asbestos
fibers are released into the air. When asbestos fibers are breathed in, they
may get trapped in the lungs and remain there for a long time. Over time,
these fibers can accumulate and cause scarring and inflammation,
which can affect breathing and lead to serious health problems (6).
Asbestos has been classified as a known human carcinogen (a substance that
causes cancer) by the U.S. Department of Health and Human Services, the EPA,
and the International Agency for Research on Cancer (2,
3, 7, 8). Studies have
shown that exposure to asbestos may increase the risk of lung cancer and mesothelioma
(a relatively rare cancer of the thin membranes
that line the chest and abdomen).
Although rare, mesothelioma is the most common form of cancer associated with
asbestos exposure. In addition to lung cancer and mesothelioma, some studies
have suggested an association between asbestos exposure and gastrointestinal
and colorectal
cancers, as well as an elevated risk for cancers of the throat,
kidney,
esophagus,
and gallbladder
(3, 4). However, the evidence is inconclusive.
Asbestos exposure may also increase the risk of asbestosis (an inflammatory
condition affecting the lungs that can cause shortness of breath, coughing,
and permanent lung damage) and other nonmalignant lung and pleural disorders,
including pleural plaques (changes in the membranes surrounding the lung),
pleural thickening, and benign pleural
effusions (abnormal collections of fluid
between the thin layers of tissue
lining the lungs and the wall of the chest cavity). Although pleural plaques
are not precursors to lung cancer, evidence suggests that people with pleural
disease caused by exposure to asbestos may be at increased risk for lung cancer
(2, 9).
- Who is at risk for an asbestos-related disease?
Everyone is exposed to asbestos at some time during their life. Low levels
of asbestos are present in the air, water, and soil. However, most people
do not become ill from their exposure. People who become ill from asbestos
are usually those who are exposed to it on a regular basis, most often in
a job where they work directly with the material or through substantial environmental
contact.
Since the early 1940s, millions of American workers have been exposed to
asbestos. Health hazards from asbestos fibers have been recognized in workers
exposed in the shipbuilding trades, asbestos mining and milling, manufacturing
of asbestos textiles and other asbestos products, insulation work in the construction
and building trades, and a variety of other trades. Demolition workers, drywall
removers, asbestos removal workers, firefighters, and automobile workers also
may be exposed to asbestos fibers. Studies evaluating the cancer risk experienced by automobile mechanics exposed to asbestos through brake repair are limited, but the overall evidence suggests there is no safe level of asbestos exposure (3, 8). As a result of Government
regulations and improved work practices, today’s workers (those without
previous exposure) are likely to face smaller risks than did those exposed
in the past.
Individuals involved in the rescue, recovery, and cleanup at the site of
the September 11, 2001, attacks on the World Trade Center (WTC) in New York
City are another group at risk of developing an asbestos-related disease.
Because asbestos was used in the construction of the North Tower of the WTC,
when the building was attacked, hundreds of tons of asbestos were released
into the atmosphere. Those at greatest risk include firefighters, police officers,
paramedics, construction workers, and volunteers who worked in the rubble
at Ground Zero. Others at risk include residents in close proximity to the
WTC towers and those who attended schools nearby. These individuals will need
to be followed to determine the long-term health consequences of their exposure
(10).
One study found that nearly 70 percent of WTC rescue and recovery workers
suffered new or worsened respiratory symptoms while performing work at the
WTC site. The study describes the results of the WTC Worker and Volunteer
Medical Screening Program, which was established to identify and characterize
possible WTC-related health effects in responders. The study found that about
28 percent of those tested had abnormal lung function tests, and 61 percent
of those without previous health problems developed respiratory symptoms (11).
However, it is important to note that these symptoms may be related to exposure
to debris components other than asbestos.
Although it is clear that the health risks from asbestos exposure increase
with heavier exposure and longer exposure time, investigators have found asbestos-related
diseases in individuals with only brief exposures. Generally, those who develop
asbestos-related diseases show no signs of illness for a long time after their
first exposure. It can take from 10 to 40 years or more for symptoms of an
asbestos-related condition to appear (2).
There is some evidence that family members of workers heavily exposed to
asbestos face an increased risk of developing mesothelioma (6).
This risk is thought to result from exposure to asbestos fibers brought into
the home on the shoes, clothing, skin, and hair of workers. To decrease these
exposures, Federal law regulates workplace practices to limit the possibility
of asbestos being brought home in this way. Some employees may be required
to shower and change their clothes before they leave work, store their street
clothes in a separate area of the workplace, or wash their work clothes at
home separately from other clothes (2).
Cases of mesothelioma have also been seen in individuals without occupational
asbestos exposure who live close to asbestos mines (6).
- What factors affect the risk of developing
an asbestos-related disease?
Several factors can help to determine how asbestos exposure affects an individual,
including (2, 6):
- Dose (how much asbestos an individual was exposed to).
- Duration (how long an individual was exposed).
- Size, shape, and chemical makeup of the asbestos fibers.
- Source of the exposure.
- Individual risk
factors, such as smoking and pre-existing lung disease.
Although all forms of asbestos are considered hazardous, different types
of asbestos fibers may be associated with different health risks. For example,
the results of several studies suggest that amphibole forms of asbestos may
be more harmful than chrysotile, particularly for mesothelioma risk, because
they tend to stay in the lungs for a longer period of time (1,
2).
- How does smoking affect risk?
Many studies have shown that the combination of smoking and asbestos exposure
is particularly hazardous. Smokers who are also exposed to asbestos have a
risk of developing lung cancer that is greater than the individual risks from
asbestos and smoking added together (3, 6).
There is evidence that quitting smoking will reduce the risk of lung cancer
among asbestos-exposed workers (4). Smoking combined with
asbestos exposure does not appear to increase the risk of mesothelioma (9).
However, people who were exposed to asbestos on the job at any time during
their life or who suspect they may have been exposed should not smoke.
- How are asbestos-related diseases detected?
Individuals who have been exposed (or suspect they have been exposed) to
asbestos fibers on the job, through the environment, or at home via a family
contact should inform their doctor about their exposure history and whether
or not they experience any symptoms. The symptoms of asbestos-related diseases
may not become apparent for many decades after the exposure. It is particularly
important to check with a doctor if any of the following symptoms develop
(6):
- Shortness of breath, wheezing, or hoarseness.
- A persistent cough that gets worse over time.
- Blood
in the sputum
(fluid) coughed up from the lungs.
- Pain or tightening in the chest.
- Difficulty swallowing.
- Swelling of the neck or face.
- Loss of appetite.
- Weight loss.
- Fatigue
or anemia.
A thorough physical
examination, including a chest
x-ray and lung function tests, may be recommended. The chest x-ray
is currently the most common tool used to detect asbestos-related diseases.
However, it is important to note that chest x-rays cannot detect asbestos
fibers in the lungs, but they can help identify any early signs of lung disease
resulting from asbestos exposure (2).
Studies have shown that computed tomography (CT)
(a series of detailed pictures of areas inside the body taken from different
angles; the pictures are created by a computer linked to an x-ray machine)
may be more effective than conventional chest x-rays at detecting asbestos-related
lung abnormalities in individuals who have been exposed to asbestos (12).
A lung biopsy, which detects microscopic
asbestos fibers in pieces of lung tissue removed by surgery,
is the most reliable test to confirm the presence of asbestos-related abnormalities.
A bronchoscopy
is a less invasive test than a biopsy and detects asbestos fibers in material
that is rinsed out of the lungs. It is important to note that these tests
cannot determine how much asbestos an individual may have been exposed to
or whether disease will develop (12). Asbestos fibers can
also be detected in urine, mucus, or feces, but these tests are not reliable
for determining how much asbestos may be in an individual’s lungs (2).
- How can workers protect themselves from asbestos
exposure?
The Occupational Safety and Health Administration (OSHA)
is a component of the U.S. Department of Labor (DOL) and is the Federal agency
responsible for health and safety regulations in maritime, construction, manufacturing,
and service workplaces. OSHA established regulations dealing with asbestos
exposure on the job, specifically in construction work, shipyards, and general
industry that employers are required to follow. In addition, the Mine
Safety and Health Administration (MSHA), another component of the
DOL, enforces regulations related to mine safety. Workers should use all protective
equipment provided by their employers and follow recommended workplace practices
and safety procedures. For example, National Institute for Occupational Safety
and Health (NIOSH)-approved respirators that fit properly should be worn by
workers when required.
Workers who are concerned about asbestos exposure in the workplace should
discuss the situation with other employees, their employee health and safety
representative, and their employers. If necessary, OSHA can provide more information
or make an inspection. Regional offices of OSHA are listed in the “United
States Government” section of a telephone directory’s blue pages
(under “Department of Labor”). Regional offices can also be found
at http://www.osha.gov/html/RAmap.html
on the Internet.
More information about asbestos is available on the OSHA Asbestos Web page,
which has links to information about asbestos in the workplace, including
what OSHA standards apply, the hazards of asbestos, evaluating asbestos exposure,
and controls used to protect workers. This page is available at http://www.osha.gov/SLTC/asbestos/index.html
on the Internet. OSHA’s national office can be contacted at:
Organization: |
Office of Public Affairs
Occupational Safety and Health Administration
U.S. Department of Labor |
Address: |
Room N–3649
200 Constitution Avenue, NW.
Washington, DC 20210 |
Telephone: |
202–693–1999
1–800–321–6742 (1–800–321–OSHA) |
TTY (for deaf or hard of hearing callers): |
1–877–889–5627 |
Internet Web site: |
http://www.osha.gov/as/opa/worker/index.html
(workers’ page) |
Mine workers can contact MSHA at:
The National Institute for Occupational Safety and Health (NIOSH),
which is part of the Centers for Disease Control and Prevention (CDC), is
another Federal agency that is concerned with asbestos exposure in the workplace.
NIOSH conducts asbestos-related research, evaluates work sites for possible
health hazards, and makes exposure control recommendations. In addition, NIOSH
distributes publications on the health effects of asbestos exposure and can
suggest additional sources of information. NIOSH can be contacted at:
Organization: |
Education and Information Division
Information Resources Branch
National Institute for Occupational Safety and Health |
Address: |
4676 Columbia Parkway
Cincinnati, OH 45226 |
Telephone: |
1–800–CDC–INFO (1–800–232–7636)
|
E-mail: |
cdcinfo@cdc.gov |
Internet Web site: |
http://www.cdc.gov/niosh |
- What programs are available to help individuals
with asbestos-related diseases?
Some people with asbestos-related illness may be eligible for Medicare
coverage. Information about benefits is available from Medicare’s Regional
Offices, located in 10 major cities across the United States and serving specific
geographic areas. The Regional Offices serve as the agency’s initial
point of contact for beneficiaries, health care providers, state and local
governments, and the general public. Contact information for each Regional
Office can be found at http://www.cms.hhs.gov/RegionalOffices on the Internet.
General information about Medicare is available by calling toll-free 1–800–633–4227
(1–800–MEDICARE) or visiting http://www.medicare.gov
on the Internet.
People with occupational asbestos-related diseases also may qualify for financial
help, including medical payments, under state workers’ compensation
laws. Because eligibility requirements vary from state to state, workers employed
by private companies or by state and local government agencies should contact
their state workers’ compensation board. Contact information for state
workers’ compensation officials may be found in the blue pages of a
local telephone directory or at http://www.dol.gov/esa/regs/compliance/owcp/wc.htm
on the Internet.
If exposure occurred during employment with a Federal agency, medical expenses
and other compensation may be covered by the Federal Employees’
Compensation Program, which is administered by the DOL, Employment
Standards Administration’s Office of Workers’ Compensation Programs.
This program provides workers’ compensation benefits to Federal (civilian)
employees for employment-related injuries and diseases. Benefits include wage
replacement, payment for medical care, and, where necessary, medical and vocational
rehabilitation
assistance in returning to work. Benefits may also be provided to dependents
if the injury or disease causes the employee’s death. The program has
12 district offices nationwide.
In addition, the Longshore and Harbor Workers’ Compensation
Program provides benefits to longshoremen, harbor workers, other
maritime workers, and other classes of private industry workers who are injured
during the course of employment or suffer from diseases caused or worsened
by conditions of employment. Information about eligibility and how to file
a claim for benefits under either of these programs is available from:
Organization: |
Office of Workers’ Compensation Programs
Employment Standards Administration
U.S. Department of Labor |
Address: |
Frances Perkins Building
200 Constitution Avenue, NW.
Washington, DC 20210 |
Telephone: |
1–866–692–7487 (1–866–OWCPIVR)
202–693–0040
(Federal Employees’ Compensation Program)
202–693–0038
(Longshore and Harbor Workers’ Compensation Program)
|
E-mail: |
OWCP-Public@dol.gov |
Internet Web site: |
http://www.dol.gov/esa/owcp/index.htm |
Eligible veterans may receive health care at a Department of Veterans
Affairs (VA) Medical Center for an asbestos-related disease. Veterans
can receive treatment for service-connected and nonservice-connected medical
conditions. Information about eligibility and benefits is available from the
VA Health Benefits Service Center at 1–877–222–8387 (1–877–222–VETS)
or on the VA Web site at http://www1.va.gov/health/index.asp
on the Internet.
- Is there Federal legislation to help victims
of asbestos-related diseases?
No Federal legislation has been enacted to compensate victims of asbestos-related
diseases or to protect people from asbestos exposure. However, a bill called
the Fairness in Asbestos Injury Resolution Act, or FAIR Act, has been introduced
in Congress several times. This bill would create a national trust fund to
compensate victims suffering from asbestos-related diseases. The proposed
trust fund would be administered by the DOL, outside of the courts, through
a claims process in which all individuals with certain medical symptoms and
evidence of asbestos-related disease would be compensated. Funding for the
trust would come from insurance companies and companies that mined, manufactured,
and sold asbestos or asbestos products. Under the bill, individuals affected
by asbestos exposure would no longer be able to pursue awards for damages
in any Federal or state court.
- What other organizations offer information
related to asbestos exposure?
The organizations listed below can provide more information about asbestos
exposure.
The Agency for Toxic Substances and Disease Registry (ATSDR)
is the principal Federal agency responsible for evaluating the human health
effects of exposure to hazardous substances. This agency works in close collaboration
with local, state, and other Federal agencies, with tribal governments, and
with communities and local health care providers to help prevent or reduce
harmful human health effects from exposure to hazardous substances. The ATSDR
provides information about asbestos and where to find occupational and environmental
health clinics. The ATSDR can be contacted at:
Organization: |
Agency for Toxic Substances and Disease Registry |
Address: |
4770 Buford Highway, NE.
Atlanta, GA 30341 |
Telephone: |
1–800–232–4636 (1–800–CDC–INFO) |
TTY: |
1–888–232–6348 |
E-mail: |
cdcinfo@cdc.gov |
Internet Web site: |
http://www.atsdr.cdc.gov |
The U.S. Environmental Protection Agency (EPA) regulates
the general public’s exposure to asbestos in buildings, drinking water,
and the environment. The EPA offers a Toxic Substances Control Act (TSCA)
Hotline and an Asbestos Ombudsman. The TSCA Hotline provides technical assistance
and information about asbestos programs implemented under the TSCA, which
include the Asbestos School Hazard Abatement Act and the Asbestos Hazard Emergency
Response Act. The Asbestos Ombudsman focuses on asbestos in schools and handles
questions and complaints. Both the TSCA Hotline and the Asbestos Ombudsman
can provide publications on a number of topics, particularly on controlling
asbestos exposure in schools and other buildings. The Ombudsman operates a
toll-free hotline for small businesses, trade associations, and others seeking
free, confidential help.
The EPA Web site includes a list of EPA regional and state asbestos contacts
at http://www.epa.gov/asbestos/pubs/regioncontact.html
on the Internet. In addition, EPA’s Asbestos and Vermiculite home page
provides information about asbestos and its health effects and links to asbestos
resources, including suggestions for homeowners who suspect asbestos in their
homes, and laws and regulations applicable to asbestos. This page can be found
at http://www.epa.gov/asbestos on
the Internet. Questions may be directed to:
Organization: |
U.S. Environmental Protection Agency
EPA West Building
National Program Chemicals Division |
Address: |
Mail Code 7404T
1200 Pennsylvania Avenue, NW.
Washington, DC 20460 |
TSCA Hotline: |
202–554–1404 |
TTY: |
202–554–0551 |
Asbestos Ombudsman: |
1–800–368–5888 |
E-mail: |
tsca-hotline@epa.gov |
Internet Web site: |
http://www.epa.gov/asbestos |
Another EPA resource that may be of interest is the brochure titled Current
Best Practices for Preventing Asbestos Exposure Among Brake and Clutch Repair
Workers. Released in April 2007, this brochure includes work practices
for both automotive professionals and home mechanics that may be used to avoid
asbestos exposure. It also summarizes existing OSHA regulatory requirements
for professional auto mechanics. The brochure can be found at http://www.epa.gov/asbestos/pubs/brakesbrochure.html
on the Internet.
The U.S. Consumer Product Safety Commission (CPSC) is responsible
for protecting the public from unreasonable risks of serious injury or death
from more than 15,000 types of consumer products, including asbestos, under
the agency’s jurisdiction. The CPSC maintains a toll-free 24-hour hotline
where callers can obtain product safety and other agency information and report
unsafe products. In addition, CPSC publications provide guidelines for repairing
and removing asbestos, and general information about asbestos in the home.
CPSC can be contacted at:
Organization: |
Office of Information and Public Affairs
U.S. Consumer Product Safety Commission |
Address: |
4330 East West Highway
Bethesda, MD 20814 |
Telephone: |
1–800–638–2772 |
TTY: |
1–800–638–8270 |
E-mail: |
info@cpsc.gov |
Internet Web site: |
http://www.cpsc.gov |
Individuals can also contact their local or state health department with
questions or concerns about asbestos.
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