Asbestos is a type of mineral that has been commonly used for commercial purposes and has been categorized into two main types, serpentine and amphibole. Although six types of naturally-occurring minerals are officially recognized by the U.S Bureau of Mines as asbestos, more than 100 are listed as “asbestos-like.” The Environmental Protection Agency has identified amosite, crocidolite, tremolite, anthophyllite and actinolite as the different classes of asbestos.
Scientists and doctors have linked all forms of asbestos to the development of serious health conditions such as mesothelioma, asbestosis and lung cancer, among others. Chrysotile, the most common form of asbestos, makes up approximately 95 percent of the asbestos present in buildings manufactured before the 1980s. Scientific data has shown that exposure to the long, wispy fibers of asbestos can be hazardous to human health.
Asbestos Regulation and Exposure
Asbestos House Diagram
Although 52 countries have enacted a ban on asbestos use, those that have not yet issued a ban account for a large portion of asbestos use each year. According to a 2009 U.S. Geological Study (USGS), approximately 2 million tons of asbestos was produced by the late 1990s.
Russia is considered to be the largest producer of asbestos products in the world and exports asbestos to developing countries that have not currently issued asbestos regulations. In the USGS study, the major consumers of asbestos included countries such as China, Russia, Kazakhstan, Brazil, Canada, India and Colombia. While Canada is a major producer of chrysotile asbestos, it is currently very limited for use in that country.
In 1999, the U.S. used about 15,000 metric tons of asbestos. Many major health organizations around the world have recognized asbestos as a known human carcinogen. In 1977, the International Agency for Research on Cancer, part of the World Health Organization, was the first agency to recognize the potentially harmful effects of asbestos exposure. However, many countries still have not banned asbestos.
Health Risks from Asbestos
Numerous medical studies have sought the source behind the toxic effects of asbestos on the body. In the 2003 Vermont Medical Center study “Multiple Roles of Oxidants in the Pathogenesis of Asbestos-Induced Diseases,” researchers found that oxidants found in the crocidolite and amosite forms of asbestos had a damaging effect on DNA and may contribute to asbestos-related lung injuries. Asbestos can cause the over-regulation of antioxidant enzymes in human cells.
A 2010 study by the Mesothelioma Applied Research Foundation and the National Cancer Institute located a protein that played key role in the development of mesothelioma. The protein, HMGB1, was found in elevated levels of patients who had been exposed to asbestos. The researchers learned that as the result of asbestos exposure, the presence of this protein can lead to an inflammatory reaction that causes tumor growth. The study also found that asbestos fibers in the human body kill a cell through “programmed cell necrosis” or cell suicide. Researchers proposed that interfering with the reactions between asbestos fibers and HMGB1 may decrease the development of cancerous tumors.
At very high concentrations, asbestos fibers can cause the formation of lesions because the human body is not able to expel the fibers once they have entered the body. Cells in the mesothelium attempt to repair these lesions but are not able to and, as a result, the cells begin to die in massive numbers. The genomic alterations caused by asbestos fibers eventually lead to large chromosomal deletions that appear to be associated with cell death. Because the body is not able to expel these fibers, tumors can form.
Occupational Asbestos Exposure
The majority of asbestos-related incidences that occur each year are the result of occupational exposure. A large percentage of individuals who have been affected by asbestos are Armed Forces veterans. Higher workforce death rates have been associated with industries that had a history of working with asbestos.
According to the World Health Organization, about 125 million people have been exposed to asbestos at the workplace, and more than 107,000 workers around the world die every year from asbestos-related diseases.
The U.S. National Institute for Occupational Safety and Health (NIOSH) estimates that five deaths from lung cancer and two deaths from asbestosis will occur for every 1,000 workers exposed to asbestos in a working lifetime. Mortality rates may be higher in some industries. In one Virginia shipbuilding location, the occurrence of mesothelioma was seven times higher than the national rate. Some common industries that produced or manufactured products using asbestos include shipyards, construction and power plants.
Resources for Patients
If you have been exposed to asbestos, it is imperative to seek medical help before health conditions occur. Many patients are unaware of the potential dangers that asbestos fibers pose on their body, much of which they were exposed to years ago. Asbestos-related diseases typically have a long latency period, and symptoms arise later in life. If you would like more information about asbestos-related diseases.
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