Asbestos Cancer

Asbestos has been linked to a number of lung diseases including asbestosis, pleural plaques/effusions, and mesothelioma. Asbestos is also an important cause of small cell and non-small cell lung cancer. There are a number of lines of evidence that asbestos is clearly linked to lung cancer including laboratory, epidemiological, and clinical research. Among medical professionals, asbestos is now universally accepted as a cause of lung cancer.

DNA damage is the hallmark of the cancerous transformation of cells. Asbestos fibers have been shown to be able to kill cells, delete large stretches of DNA from a cell’s genome, and damage chromosomes (bundles of DNA that make up the genome). The silicate fiber may cause DNA damage through oxidative damage because antioxidants can reduce the damage in laboratory studies. Asbestos contributes to inflammation and fibrosis, which may exacerbate cancer formation/propagation.

The clinical evidence linking asbestos to lung cancer dates back to at least the 1930s, though an association was theorized in the 1890s. The original epidemiological evidence began appearing in the scientific literature in the 1950s. It was found that asbestos textile workers in India were ten times more likely to develop lung cancer than matched controls. In the United States, the increased lung cancer risk in asbestos insulation workers was found to be sevenfold.

It became clear that the risk of lung cancer increases in a dose-dependent fashion. In other words, people with higher or longer exposure to asbestos fibers have a higher the risk of developing lung cancer. This is considered more or less definitive evidence of a causal link from an epidemiological perspective.