Mesothelioma May Be Caused By Even Low Asbestos Exposure: Study

New research highlights how individuals exposed to even very low levels of asbestos may face a risk of developing mesothelioma and other cancers linked to the toxic substance.  

In a study published in the Journal of Occupational and Environmental Medicine, researchers from Norway looked at thousands of men who worked jobs that subjected them to asbestos exposure. They found increased risks of three types of cancer, including pleural mesothelioma, lung cancer, and laryngeal cancer.

Researchers looked at data on 58,279 Norwegian men between the ages of 55 and 69, examining the asbestos exposure experienced by the men via estimates based on their work history.

After 17.3 years of follow-up, researcher found that the group of men experienced 2,324 cases of lung cancer, 166 cases of laryngeal cancer, and 132 cases of pleural mesothelioma. They found associations between asbestos exposure and development of all three ailments.

Even low levels of asbestos exposure were associated with an increased risk of all three cancers. Researchers also found an association between asbestos exposure and lung adenocarcinoma and glottis cancer, but only in cases of prolonged, higher asbestos exposure.

Of the three cancers tracked at all levels, mesothelioma was the least prevalent, but also the deadliest. Mesothelioma is only known to be caused by exposure to asbestos and breathing asbestos fibers.  There are no known effective treatments for the disease and individuals diagnosed with mesothelioma typically have a very short life-expectancy since it is often not discovered until years after asbestos exposure, when the cancer is already very advanced.

Asbestos was widely used in a variety of manufacturing and construction applications throughout the last century, with use peaking in 1973. Most uses of asbestos were banned in the mid-1980s.

Mesothelioma litigation is the longest-running mass tort in U.S. history, with more than 600,000 people having filed a lawsuit against more than 6,000 defendants after being diagnosed with cancer that was allegedly caused by inhaling asbestos fibers.

In addition to cases for individuals directly exposed, in recent years there have been a growing number of second-hand asbestos exposure lawsuits brought on behalf of family members were exposed to fibers carried home on clothing or in the hair of individuals working with the material. Cases have been brought by individuals who were exposed as young children or babies when their parents would hold them after returning home from work with asbestos.

According to a 2009 report by the U.S. Centers for Disease Control and Prevention (CDC), the number of cases of malignant mesothelioma are just now peaking, since there is a long latency period of 20 to 40 years between exposure an diagnosis.