CHEMICAL HAZARD - Asbestos Exposure

Asbestos Exposure

Asbestos is a group of minerals with thin microscopic fibers. Because these fibers are resistant to heat, fire, and chemicals and do not conduct electricity, asbestos has been mined and used widely in the construction, automotive, and other industries.

If products containing asbestos are disturbed, the tiny fibers are released into the air. When they are breathed in, they can become trapped in the lungs and stay there for many years. Over time these fibers can accumulate and lead to serious health problems, including:

• Asbestosis, an inflammatory condition of lungs that can cause shortness of breath, coughing, and eventually scarring of the lungs that makes it hard to breathe.
• Mesothelioma, a rare cancer that affects the lining of the lungs, chest cavity, or abdomen.
• Lung cancer.
• Other lung problems, including pleural plaques (changes in the membranes surrounding the lungs), thickening of the membranes that surround the lungs, and pleural effusions (abnormal collections of fluid between the lungs and the inside wall of the chest.

Studies have also suggested an association between asbestos exposure and other cancers, including cancers of the gastrointestinal tract, throat, kidney, brain, bladder, voice box, gallbladder, and others. However, the evidence is inconclusive.

Asbestos Exposure: Causes and Risks

Asbestos exposure may occur in the workplace, home, or community. Mined and used commercially since the 1800s, asbestos has been used in many products, including: car brake shoes and clutch pads; building materials, including ceiling and floor tiles; paints, coatings, and adhesives; plastics; vermiculite-containing garden products; and some talc-containing crayons. Due to federal regulations and health concerns, asbestos is much less widely used than it was just a few decades ago.

Most cases of asbestos poisoning occur in asbestos workers; however, there is some evidence that family members of workers heavily exposed to asbestos face an increased risk of developing mesothelioma, possibly due to the exposure of asbestos fibers brought into the home on the clothing, skin, and hair. Cases of mesothelioma have also been seen in people living close to asbestos mines.

Another group at risk of developing asbestos-related disease is workers involved in the Sept. 11, 2001, attack on the World Trade Center in New York City. Asbestos was used in the construction of the North Tower, and hundreds of tons of asbestos were released into the atmosphere during the attack.

Several factors are involved in how asbestos exposure affects an individual. These include:

• How much asbestos a person was exposed to
• How long the person was exposed
• The size, shape and chemical makeup of the asbestos fibers
• The presence of other lung diseases

Smoking also increases the risk of problems related to asbestos exposure.

There are different forms of asbestos. Although all forms 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 (which have longer, more durable fibers) may be more harmful than chrysotile forms (which have curly fibers), particularly for mesothelioma risk, because they tend to stay in the lungs longer.

Asbestos cancer and other health problems take many years to develop. Most cases of lung cancer or asbestosis in asbestos workers occur 15 or more years after initial exposure to asbestos. For mesothelioma, the lag time is even longer. The time between initial asbestos exposure and mesothelioma commonly has been 30 years or more.

Asbestos Symptoms

The respiratory tract is the most common site of asbestos exposure symptoms. Symptoms differ depending on the particular problem.

The main symptom of asbestosis is shortness of breath. Other symptoms may include:

• Persistent cough that produces mucus
• Chest tightness
• Chest pain
• Loss of appetite
• Dry, crackling sound in lungs while inhaling

Symptoms of lung cancer can include:

• Cough (including coughing up blood)
• Wheezing
• Unexplained weight loss
• Difficulty breathing or shortness of breath
• Persistent chest pain
• Hoarseness
• Anemia

The main symptoms of mesothelioma of the lungs are shortness of breath and chest pain. Symptoms of abdominal mesothelioma can include:

• Weight loss
• Swelling and pain in the abdomen
• Blood clotting abnormalities
• Bowel obstruction
• Anemia
• Fever

Because many conditions share these symptoms, having these symptoms doesn't necessarily mean you have asbestos-related cancer or lung damage. If you experience symptoms, it's important to see your doctor.

Diagnosing Asbestos-Related Problems

Diagnosing asbestos-related health problems can take some time. The diagnostic process will begin with a medical history and physical exam. Your doctor will ask you about other medical problems you have as well as any history of asbestos exposure. Depending on the findings of the exam and history, your doctor may order tests including the following:

• X-rays of the chest and/or abdomen
• Lung function tests
• CT scans
• MRI

If your doctor suspects asbestos-related cancer or lung problems, a biopsy will be necessary to confirm the diagnosis. In a biopsy, samples of tissue or cells are removed for examination under a microscope. A biopsy may be used to detect microscopic asbestos fibers and/or cancer. Depending on the location of the tissue to be tested, a biopsy may be done in a number of ways, including the following:

Thoraccentesis. The doctor uses a long needle to remove fluid for examination from the chest.

Bronchoscopy. The doctor inserts a thin, lighted tube called a bronchoscope through the nose or mouth and into the lung, making it possible to examine the lung and air passages. Using this procedure, the doctor may also take a sample of cells with a needle, brush, or other tool.

Fine-needle aspiration. The doctor uses a thin needle to remove tissue or fluid from the lung or lymph node. The doctor may use a CT scan or other method to guide the needle to a lung tumor or lymph node.

Thoracoscopy. The doctor makes small incisions in the chest and back and then places a thin, lighted tube called a thorascope into the chest between two ribs.  This allows the doctor to view the inside of the chest and take tissue samples.

Peritoneoscopy. The doctor makes a small incision into the abdomen and inserts an instrument called a peritoneoscope into the abdominal cavity.

If the doctor needs larger tissue samples, more extensive surgery may be necessary.

Source: http://www.webmd.com/