New Asbestos Exposure Risks
Continued from: Asbestos Exposure
Asbestos fibers, while not poisonous themselves, can be dangerous if inhaled or ingested in the body. Asbestos is now known to be the primary causative factor for malignant mesothelioma. Mesothelioma is an aggressive and fatal form of cancer that starts after asbestos fibers become lodged in the lung lining. Inflammation in the lung lining, or pleura, leads to the development of cancerous tumors and the most common form of mesothelioma cancer, pleural mesothelioma. Asbestosis, or excessive scarring of the lungs, is also caused when asbestos fibers become lodged in the lungs.
Researchers now are finding that asbestos exposure may be related to other types of illnesses, including autoimmune maladies such as rheumatoid arthritis and multiple sclerosis. A recent study found a link between exposure to asbestos and autoantibody activity, suggesting a possible link between exposure and the subsequent development of an autoimmune disease.
The study was conducted in Libby, Montana, where numerous townspeople have been exposed to high quantities of asbestos dust for extended time periods. According to the author of one study, "The population of Libby, Montana provides a unique opportunity for such a study because of both occupational and environmental exposure that have occurred as a result of the mining of asbestos-contaminated vermiculite near the community."
Fifty people from Libby, MT, were recruited for comparison to 50 people from a neighboring town, where there was no known asbestos exposure. Blood samples were taken from each group for evaluation. Researchers were looking for the presence of a group of antibodies known as antinuclear antibodies, or ANA. These types of antibodies are often found in people whose immune systems are predisposed to cause inflammation against their own body organs and tissues; which happens with conditions such as multiple sclerosis, where the nerve conduction tissue degenerates over time presumably due to an autoimmune response.
The results from the Libby study show that people from Libby had levels of ANA 29 percent higher than those from the neighboring town. Further, if the person from Libby had been exposed to asbestos for five or more years, ANA levels were even higher. Also of importance was the finding that 75 percent of the people from Libby had significant lung problems. The scientists also noted that Libby residents had significantly higher levels of immunoglobin A, which is a protein produced by the immune system.
The researchers' goal was to determine if there was a link between asbestos exposure and an autoimmune response. Their results do suggest that this link exists; that is, asbestos exposure leads to increased autoimmune activity. However, it is important to note that the higher levels of ANA and other autoimmune proteins/antibodies does not indicate the presence of an autoimmune disease or of a disease process. But, such data could lead to a better understanding of the causes for autoimmune diseases and the potential dangers and risks associated with asbestos.
[Page updated August 2009]