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How Asbestos Exposure Causes Mesothelioma


Learning about the epidemiology of malignant mesothelioma is the foundation of all preventative and intervention measures. Understanding the determinate factors and causes is the first step towards knowing how to treat and control the disease.

When you are first diagnosed with mesothelioma, you may know little about this type of cancer or what causes it. Mesothelioma is a tumor that arises on the mesothelial surfaces of the pleural and peritoneal cavities, the tunica vaginalis, or the pericardium. Approximately 80% of all mesothelioma cases are pleural in origin, and there are approximately 3,000 cases diagnosed in the United States alone each year. Although the disease most commonly presents in the pleura (the two thin layers of membrane that surround the entire surface of the lung), mesothelioma also occurs in the pericardium (lining of the heart) or in the peritoneum (lining of the abdomen.)


Exposure to asbestos is considered the main cause of mesothelioma, with eighty percent diagnosed having a known history of exposure. Asbestos is the commercial name for a group of hydrated magnesium silicate fibrous minerals, commonly divided into two main types: serpentine and amphiboles. Serpentine chrysotile fibers are curly and pliable, whereas the amphiboles are thin and needle-like. Asbestos was well known for its insulating, heat and fire resistant properties and used extensively in industrial materials during World War II. Later, asbestos was used in cement, ceiling and floor tiles, automobile brake linings, and different forms of insulation.

Exposure to asbestos occurs either directly, most often occupationally, or indirectly, through coming into contact with an exposed person who brings the household into contact by carrying it home on his clothes or body.



The effects of asbestos on health first began to surface at the turn of the century, when asbestosis was linked to occupational exposure. Asbestosis is a respiratory disease caused when asbestos fibers accumulate in the lungs and cause scarring of lung tissue and shortness of breath. It was not until 1960 that the link between inhalation of asbestos and the existence of mesothelioma was established.

As the scope of the health hazard of asbestos on humans became more widely accepted, safety regulations began to be established. Despite deepening controls, many millions of people in the United States alone have been exposed to asbestos in the workplace or at home. Researchers had hoped that forbidding and/or limiting the use of asbestos would cause a decline in the number of cases reported, yet so far there is no evidence of this occurring. In addition, there is growing concern of a sharp increase in the number of cases of mesothelioma in developing countries, where use has continued and even increased despite well documented health risks.


Mesothelioma is more common in men that women, and extremely rare in children. Due to a long latency period (10 - 50 years, with the median time being 32 years) between time of exposure and development of symptoms, the disease often is not diagnosed until in its later stages. In the past, most people diagnosed with mesothelioma were older than 65, but the age at diagnosis is becoming increasingly younger every year.

Late stage diagnosis leaves fewer effective treatment methods beyond palliative measures, although new research may offer more options. The average survival time is one to two years, however this depends on the stage of cancer and whether surgical removal of the tumor is possible. Early stage discovery usually leads to better prognosis and longer survival time.

If you think you have any history of exposure to asbestos, it is imperative that you tell your doctor and have regular check ups. If diagnosed with mesothelioma, seek care and treatment from medical experts as soon as you can. Find out as much information about asbestos and mesothelioma as you can.