Mesothelioma and Asbestos Blog

Occupational asbestos exposure is the cause of the vast majory of mesothelioma cases. Workers in different industries, with different occupations have different levels of risks. Asbestos insulation workers for example are almost 100 times more likely to contract mesothelioma than the average person, while a smelter worker is about 5 times more likely. The following is a list of high-risk occupations and industries that seem to cause a large number of mesothelioma cases in their workers:

Manufacturing

The manufacture of various products containing asbestos, or products whose manufacture requires the use of equipment that contains asbestos also account for a disproportionate number of mesothelioma cases among workers. Those who work in the manufacturing of the following products are at the greatest risk:

• Building materials
• Insulation
• Roofing
• Synthetic rubber
• Pharmaceuticals
• Paints
• Plastics

Other Industries and Occupations

Not only workers in manufacturing are exposed to asbestos, however. The following occupations and industries also put their workers at a high risk of exposure and the resulting mesothelioma:

• Tile cutting, working
• Maritime working
• Shipyard working, ship building
• Plumbing
• Roofing
• Railway working
• Construction working, carpentry, and contracting
• Building inspection
• Mining
• Vehicle repair
• Welding
• Plastering
• Oil refinery
• Power plant
• Steel and iron mill
• Bricklaying
• Furnace working

There is no consensus on the details regarding the exact mechanisms by which asbestos causes mesothelioma. There is, however, a general knowledge about the processes involved.

The lungs, heart, and some abdominal organs are each surrounded by a mesothelium. The one that surrounds the lungs is called the pleural mesothelium, the one that surrounds the abdominal organs is called the peritoneal mesothelium, and the one that surrounds the heart is called the pericardial mesothelium. It is these linings (but most commonly the pleural one) that are affected by mesothelioma.

How Asbestos Enters the Body

As asbestos crumbles, tiny asbestos fibers are released. The inhalation of these fibers is far and away the most common cause of mesothelioma. When asbestos fibers are inhaled, they can work their way through the smallest of the lungs’ passages and become imbedded in the pleural mesothelium.

What Happens Then?

The body’s natural reaction to asbestos fibers is to release a fluid intended to loosen the fibers so that they can be expelled by coughing. But the fibers are tenacious, and the body’s attempts to expel them are usually ineffective.

The area around the asbestos fibers becomes irritated and inflamed. The fluid continues to be secreted, and over time, it builds up in the pleural cavity - the space between the pleural mesothelium, and the lining around the chest cavity. These effects cause the typical mesothelioma symptoms, such as coughing, wheezing, shortness of breath, and chest pain.

What about the cancer?

It is not well understood how exactly asbestos triggers malignant cell production. We do know however, that the cancer is likely either caused by direct interaction with the asbestos fibers, or by prolonged exposure to toxins that may develop in the mesothelium in the presence of asbestos. Either way, the production of cytokines - substances that control various body processes - is induced, which triggers mesothelial cell production. It is this process that is altered by the above-mentioned toxins or the asbestos fibers themselves. This alteration results in the development of malignant cells.

What about peritoneal and pericardial mesothelioma?

No one is sure how these other more rare forms of mesothelioma are caused, though many suspect it is transported from the pleural mesothelium to the peritoneal mesothelium by the lymphatic system, or ingestion, and to the pericardial mesothelium by the lymphatic system, or proximity.