Asbestos News

Asbestos is the name given to a group of very small fibers found naturally in our environment. These fibers have many desirable traits: Asbestos fibers are strong, flexible, and resistant to heat and fire. Most people are familiar with the use of asbestos as a fire retardant. Scientists classify six discrete categories of asbestos minerals:

• Chrysotile
• Actinolite
• Tremolite
• Anthophyllite
• Crocidolite
• Amosite

These six minerals are further grouped into two categories: Chrysotile, which is first on the above list, and Amphibole, which encompasses the other five. The difference is important-- Chrysotile exposure is considered to have fewer, less serious human health effects than exposure to amphibole asbestos, though asbestos exposure of any kind is considered a dangerous health hazard.

Asbestos can't be seen without a microscope; fibers are smaller than a human hair. It has no smell or taste. The fibers are mined from rocks by crushing the rock to release the fibers. These fibers are then used to strengthen materials, increase resistance to heat and fire, and reduce friction. As a result, asbestos can commonly be found in insulation, roofing tiles, flooring, automotive brakes and clutches, ships, power plants, furnaces and boilers, and cement, among many other materials. Intact materials containing asbestos pose no health threat and should not be disturbed. Only in an airborne state is asbestos dangerous, which is why many people with asbestos-related health problems are often found to have worked at jobs that agitate asbestos- containing materials. At-risk industries include construction, demolition, asbestos removal, shipbuilding, automotive manufacturing and repair, roofing, and maintenance. Though asbestos is rarely used in new materials anymore, it is frequently found in materials constructed prior to the 1970's. A study published by the Environmental Protection Agency (EPA) in 1988 found asbestos materials in 20% of public and commercial buildings.

Human Exposure to Asbestos
Because asbestos occurs naturally in our environment, we are all exposed to small amounts of it simply by breathing the air around us. This type of exposure is not a cause for concern. More extensive exposure to asbestos, however, is almost always occupational and occurs when a worker breathes in asbestos-contaminated air, either in high concentrations, or in lower concentrations over a long period of time. The fibers are inhaled into the lungs, where, over time, they cause scarring of the lung tissue and increase the risk for other diseases. This type of exposure can have very serious health consequences and should be rigorously avoided. Many U.S. government agencies have regulations in place to minimize the risk of asbestos exposure. Two of these include the Occupational Safety and Health Administration (OSHA), which protects the health of workers, and the Environmental Protection Agency (EPA), which tracks industrial releases and sets air quality standards. Even with these regulations in place, exposures can still occur, most often as a result of an industrial or occupational accident, or because of inadequate protection of a worker.

Health Risks of Asbestos Exposure
Being exposed to asbestos does not guarantee that a person will get sick. Whether someone will become ill depends on many factors, such as the extent of the exposure, the duration of the exposure, and the individual's smoking history. As one would expect, greater exposure to asbestos increases the chance of acquiring an asbestos-related disease: as exposure rises, so does the health risk. Smoking compounds this risk.

Symptoms of asbestos-related disease can include:

• shortness of breath
• cough
• coughing up blood
• chest pain
• difficulty in swallowing
• significant weight loss
• abdominal pain

Health problems resulting from asbestos exposure are almost always manifested in the lungs, can be very difficult to treat, and are, at the present time, considered impossible to cure. Asbestos fibers are so durable that the body's defenses cannot break them down. Instead, the fibers remain in the lungs, causing the scarring that interferes with breathing. The three most common diseases related to asbestos exposure are asbestosis, lung cancer, and mesothelioma.

Asbestosis
Asbestosis is marked by breathing difficulties, coughing, and an increased risk of lung infections. When asbestos fibers get lodged in the air sacs, or alveoli, of the lungs, the fibers cause scarring. This scarring inhibits what is ordinarily an easy exchange of gasses between the body and the environment. Under normal circumstances, the alveoli deliver fresh oxygen to the blood stream and remove the gaseous waste products such as carbon dioxide back to the air through very thin membranes in the cells. This process, called respiration, is, of course, vital to human health. When it is interrupted, as in asbestosis, the results can be disabling, and in some cases, fatal. The U.S. National Institute of Occupational Safety and Health (NIOSH) reported 1,265 deaths caused by asbestosis in 1999. Most of these deaths were among white males between the ages of 65 and 84 with occupational exposure to asbestos. Presented with asbestosis, a physician may recommend preventive measures for avoiding lung infections. Some of these may include pneumonia vaccinations and recommendations to avoid airborne irritants, such as dust, pollen, and tobacco smoke. There is no cure for asbestosis.

Lung cancer
Asbestos exposure is a known cause of lung cancer, a very deadly form of cancer, and the second most common cancer site in American men and women. Public health experts who track cancer rates estimate that roughly 86 American men out of 100,000 will contract lung cancer in a given year. A worker exposed to asbestos has five times that risk. This means that if all other factors are equal, approximately 430 out of 100,000 exposed workers would be expected to have lung cancer.

Cigarette smoking, a known cause of lung cancer itself, is especially dangerous for those exposed to asbestos. According to the Canadian Lung Association, smoking combined with exposure to asbestos raises a person's lung cancer risk to 50 times the risk of an unexposed man who does not smoke. That means that among 100,000 smoking, asbestos-exposed men, 4,320 would be expected to have lung cancer. Treatment for lung cancer includes surgery, radiation and/or chemotherapy.

Mesothelioma
Mesothelioma is a very painful, rare and fatal cancer of the pleura, which is the membrane that lines the lungs and greater chest area (peritoneum). Most mesothelioma cases affect the lungs; very rarely, other organs in the peritoneal area are afflicted. This type of cancer is very specific to crocidolite (also called "blue asbestos") exposure. The American Cancer Society estimates that there are 2000-3000 new cases per year of mesothelioma, though this number is expected to rise over the next few years. Mesothelioma has a long latency period--sometimes decades-- between exposure and the onset of disease. Persons exposed to asbestos often do not experience symptoms until thirty or forty years after the exposure.

While some cancers are treatable, mesothelioma is nearly always fatal, though recent breakthroughs in cancer treatment centers are improving the survival odds for mesothelioma patients. Until recently, the one-year survival rate has been less than 30%. Patients rarely lived more than 12-18 months after diagnosis. With some of the newer advances though, patients are surviving up to five years and beyond. As with many other diseases, early detection of mesothelioma is critical to prolonging longevity and promoting quality of life.

To detect asbestos exposure or an asbestos-related illness, a physician can order several tests, the first and most common of which is a chest x-ray. This illuminates any changes in the lungs. A computerized tomography scan (CT) is a more detailed x-ray involving a higher level of radiation. A CT scan shows changes more clearly and in better detail than a chest x-ray. Additionally, a lung function test may be given to determine how much air is being moved by the lungs. Less commonly used is bronchoalveolar lavage, a test in which a small bit of saline (a salt-water solution) is inserted into the lungs, then quickly sucked back up to be examined for asbestos particles or damaged cells.

For more information about asbestos, asbestos-related health effects, and government regulations concerning asbestos, please see the web sites below.
www.atsdr.cdc.gov/asbestos
www.niosh.cdc.gov
www.osha.gov
www.epa.gov
www.lungusa.org
www.pp.okstate.edu/ehs
www.asbestos-institute.ca