What is asbestos?
Asbestos is the name given to six minerals that occur naturally in the environment as bundles of fibers that can be separated into thin, durable threads for use in commercial and industrial applications. 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. Additional asbestos-like minerals are found in the natural environment, including erionite.
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.
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. 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—but 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.
In June 2000, the CPSC concluded that the risk of children’s exposure to asbestos fibers in crayons was extremely low. 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.
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 360 metric tons by 2015.
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.
Asbestos has been classified as a known human carcinogen (a substance that causes cancer) by the U.S. Department of Health and Human Services (HHS), the U.S. Environmental Protection Agency (EPA), and the International Agency for Research on Cancer (IARC). According to IARC, there is sufficient evidence that asbestos causes mesothelioma (a relatively rare cancer of the thin membranes that line the chest and abdomen), and cancers of the lung, larynx, and ovary.
Although rare, mesothelioma is the most common form of cancer associated with asbestos exposure. There is limited evidence that asbestos exposure is linked to increased risks of cancers of the stomach, pharynx, and colorectum.
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.
Erionite has also been classified as a known human carcinogen by IARC and by HHS. It is not currently regulated by the EPA.
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.
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:
• 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. Although chest x-rays cannot detect asbestos fibers in the lungs, they can help identify any early signs of lung disease resulting from asbestos exposure.
A lung biopsy, which detects microscopic asbestos fibers in pieces of lung tissue removed by surgery, is the most reliable test to confirm exposure to asbestos. 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 procedures cannot determine how much asbestos an individual may have been exposed to or whether disease will develop. Asbestos fibers can also be detected in urine, mucus, and feces, but these tests are not reliable for determining how much asbestos may be in an individual’s lungs.
Litigation Regarding Asbestos Exposure
There has been a great deal of litigation regarding asbestos exposure against manufacturers of products containing asbestos, owners of buildings containing asbestos, and employers whose employees worked with products containing asbestos. Laws vary from state to state, but lawsuits for asbestos exposure are usually based on legal theories such as negligence, strict liability, or breach of warranty.
Asbestos is a naturally occurring mineral composed of thin, durable fibers resistant to heat, fire, chemicals, and electricity, making it useful in various industries. In Texas, asbestos use and handling are regulated by both federal and state laws. The Texas Department of State Health Services (DSHS) administers the Texas Asbestos Health Protection Rules, which align with the federal National Emission Standards for Hazardous Air Pollutants (NESHAP) under the Clean Air Act. These regulations govern the abatement, renovation, and demolition of buildings containing asbestos to prevent the release of asbestos fibers into the air. Additionally, the Texas Asbestos Health Protection Act requires licensing for businesses and individuals who conduct asbestos-related activities. The U.S. Environmental Protection Agency (EPA) has banned certain uses of asbestos and requires schools to inspect for and manage asbestos. Despite its useful properties, asbestos exposure is linked to serious health issues, including mesothelioma, lung cancer, and asbestosis. Due to these risks, there has been significant litigation against manufacturers, property owners, and employers related to asbestos exposure. Victims of asbestos-related diseases may seek legal recourse based on negligence, strict liability, or breach of warranty, depending on the circumstances of their exposure.
