1. What is asbestos?
Asbestos refers to a group of magnesium silicates which have both a crystalline and a fibrous structure: actinolite, tremolite anthophyllite, crocidolite, amosite, and chrysotile.The word asbestos is of ancient Greek origin; the orignial word in Greek meant ‘unquenchable' or ‘inextinguishable’.
`2. Where is asbestos found?
Major asbestos deposits are found in Russia, China, Canada, Brazil, Kazakhistan, South Africa, and Zimbabwe. Smaller outcrops are found in North America and southern Europe.
3. What are asbestos's properties?
Asbestos is extremely resistant to heat and flame, and is an excellent insulator. Its short fibers can enhance the strength of cements and plasters. They are so light and flexible that they can be spun and woven into fabric.
4. How is asbestos used?
Since the late 19th century asbestos has been used in hundreds of products and applications, including cement building materials, reinforcement in asbestos-cement products, brakes and clutches, water and sewage pipes, sprayed fire-proofing products, fire resistant insulation boards, floor tiles and coverings, gas masks, lifts and machinery. Boilers and pipes were insulated with asbestos products in factories, steel plants, and power stations, and also in hospitals, schools, and home. Shipbuilding facilities and railroads relied on asbestos as a primary insulator. Building contractors used asbestos in industrial and domestic construction for acoustic and thermal insulation, condensation protection and fireproofing. Home appliances such as irons and toasters have used asbestos insulation.
5. How does asbestos cause cancer?
In the course of mining, manufacturing and installing asbestos products, tiny asbestos fibers become airborne. Most inhaled fibers are cleared from the lungs within hours of inhalation. Coughing carries them to the throat in a layer of mucus, where they are either spit out, or swallowed, and make their way out of the body.
The inhaled asbestos fibers that are not expelled stay in the lungs, moving toward the lower regions of the lungs and progressing into the alveoli, the tiny pockets within the lung where oxygen passes into the bloodstream. Once asbestos fibers reach the alveoli, they remain for years, even the rest of a person's life. Asbestos fibers that remain embedded in the lungs can irritate the tissue, and cause changes in the way cells reproduce. These changes can lead to asbestosis, mesothelioma, and lung cancer, serious, fatal diseases.
6. What is asbestosis?
Asbestosis is a progressive disease of the lungs caused by inhaling asbestos fibers that irritate the lung cells, causing the growth of scar-like tissue in the lungs and in the pleural membrane that surrounds the lungs. The scar tissue is thicker and less flexible than normal lung tissue, and cannot expand and contract as easily. Breathing becomes more difficult and painful for the affected person. The scar tissue makes it harder for oxygen to penetrate into the alveoli, the tiny sacs in the lung where oxygen exchange takes place. Asbestosis victims make a characteristic crackling sound when they inhale. Asbestosis also causes a chronic shortness of breath and fatigue, so that many asbestosis victims require constant oxygen. There is no treatment that can reverse asbestosis. Asbestosis is a serious, painful disease which can cause disability or death.
7. What is lung cancer?
Lung cancer is the most frequently occurring cancer in the US, accounting for 30% of all diagnosed cancer. The largest number of asbestos related deaths occurs from lung cancer. Most lung cancer caused by asbestos inhalation starts in the lining of the bronchi, the tubes that lead from the windpipe into each lung. Lung cancer caused by asbestos exposure can also begin in the windpipe itself, the bronchioles, smaller tubes which branch off from the bronchi, or in the alveoli. Lung cancer tends to metastasize, spreading to other organs of the body, such as the brain or the liver.
Workers with long exposure asbestos have 3 to 4 times greater risk of developing lung cancer than workers who have not been exposed to asbestos. Asbestos workers who smoke tobacco increase their risk of getting lung cancer by a factor of 50 to 100. Common symptoms include a persistent cough, chest pain, shortness of breath, fatigue, hoarseness, and anemia.
