Asbestos, a naturally occurring mineral, is a known human carcinogen
Exposure to asbestos takes place when a person inhales or ingests asbestos fibers from the air. Once inside the body, asbestos fibers can travel through the bloodstream and reach various organs, to which they will attach to and gradually cause inflammation and tissue scarring. Within 20 to 50 years, inflammation and tissue scarring may give way to a form of cancer. The following are the most common types of cancer asbestos exposure can lead to.
As a rare and aggressive form of cancer, mesothelioma affects the outer lining of the lungs, medically known as pleura. Every year, approximately 3,000 people in the United States are diagnosed with mesothelioma. However, the disease can also occur on the outer lining of the heart, the abdomen, and the testicles, depending on the area of the body the asbestos fibers reached. Pleural mesothelioma, the most common type, occurs in 75% of people with this diagnosis. The average age of diagnosis is between 65 and 72, as it may take up to 50 years for mesothelioma to develop following asbestos exposure. It is worthy of note that asbestos exposure is the primary cause of mesothelioma.
Usually occurring as a consequence of tobacco smoking, which accounts for 80% of cases, lung cancer can also be the result of asbestos exposure if asbestos fibers attach themselves to the inside of the lungs. While only 4% of lung cancers are caused by asbestos exposure, the disease is very prevalent among individuals with a history of asbestos exposure, such as former industrial workers and veterans. Every year, approximately 4,800 people lose their lives to lung cancer caused by asbestos exposure. It is noteworthy that smoking can increase the risk of developing lung cancer in people with a history of asbestos exposure by 50 to 85 times. While non-small cell lung cancer is the most frequently diagnosed type among people who were exposed to asbestos, small cell lung cancer is also common. The causal relation between asbestos exposure and lung cancer was established in 1942 by the National Cancer Institute. It usually takes 15 to 35 years for lung cancer to develop following asbestos exposure.
Over 16,000 people are diagnosed with esophageal cancer every year in the United States, among who are a significant number of asbestos exposure victims. Esophageal cancer affects the esophagus, which is the muscular tube connecting the throat with the stomach. When asbestos fibers become embedded in the esophagus, malignant tumors may develop over several decades. The average five-year survival rate for esophageal cancer is 19%. Esophageal cancer is the seventh leading cause of cancer death among men. Similarly to lung cancer, tobacco smoking influences the risk of developing esophageal cancer in people with a history of asbestos exposure.
The term throat cancer refers to malignant diseases that occur on the larynx, tonsils, and pharynx. Pharyngeal cancer affects the pharynx, which is the tube connecting the nose and mouth to the esophagus. Both inhalation and ingestion of asbestos fibers can lead to pharyngeal cancer, which is the case in over 53,000 Americans every year. The average age of diagnosis is 62.
A causal relation between asbestos exposure and laryngeal cancer was discovered in 2009 by the International Agency for Research on Cancer. Over 12,000 new cases of laryngeal cancer are diagnosed annually in the United States.
Tonsil cancer falls under the category of oral and oropharyngeal cancer. It is important to note that infection with HPV increases the risk of developing tonsil cancer to a great extent, as the human papillomavirus was found in up to 93% of people diagnosed with tonsil cancer.
In people with asbestos exposure, pharyngeal, laryngeal, and tonsil cancer will develop within 20 to 50 years after their first contact with the dangerous mineral. Smoking contributes to the development of throat cancer significantly in people with a history of asbestos exposure.
Also known as bronchial adenoma, this cancer is a rare malignant disease that develops on the mucous glands and ducts of the airways, the windpipe, and the salivary glands. People who were exposed to asbestos for a prolonged time are at high risk for bronchial cancer, as they inevitably breathed in and swallowed asbestos fibers from the air. Over 13% of people who receive a cancer diagnosis in the United States every year have bronchial cancer. The majority of bronchial cancers are non-small cell, namely 80% of cases, whereas 15% of them are small cell.
A correlation between asbestos exposure and gastrointestinal cancer was first revealed in 1997, when a study discovered a high prevalence of this malignant disease in 12 occupational groups which handled asbestos on a daily basis, including sheet metal workers and mechanics. Gastrointestinal cancer may develop if one ingests asbestos fibers regularly, which attach themselves to the lining of the stomach and gradually produce inflammation and tissue scarring. Within 20 to 50 years, malignant tumors may develop inside the stomach in people with a history of asbestos exposure. Every year, over 27,000 people receive a stomach cancer diagnosis throughout the country. The average age of diagnosis is 68. The term gastrointestinal cancer encompasses malignant diseases that affect the esophagus, stomach, liver, and gallbladder. It is worthy of note that men are more likely to develop gastrointestinal cancer, as they made up the majority of former industrial workers and veterans during the last century.
This cancer can occur in the colon, rectum, or appendix. Annually, nearly 148,000 people are diagnosed with colorectal cancer in the United States. Because asbestos fibers can travel through the bloodstream, they can easily reach and become embedded to the colon, rectum, or appendix, gradually causing inflammation and tissue scarring which may, in turn, give way to malignant tumors. A connection between asbestos exposure and colorectal cancer was found in 1986 by the Occupational Safety and Health Administration. The average age of diagnosis is 68 for men and 72 for women.
Although these cancers were proven to be a direct consequence of asbestos exposure, there are others that may be caused by it, but further medical research is necessary to establish a definitive causal relation. Some of the cancers which may be the result of asbestos exposure are ovarian cancer, kidney cancer, pancreatic cancer, and bladder cancer. For people with these other types of cancer diagnosis they usually have a secondary diagnosis evaluation for their lungs, where asbestos fibers can be identified by scarring or nodules present.