We are probably all familiar with the dangers of asbestos in your rooftop or in various pieces of old equipment as it has been shown that the microscopic asbestos particles reach our lungs and can then potentially cause lung cancer.
Now smoking (for example) can cause cancer because of various carcinogens chemically interacting with DNA, but how can these asbestos particles, specifically prized for being quite unreactive, damage DNA to the point of triggering cancer?
More basic answer; the asbestos crystals have hooks. So the cilia in the lungs have difficulty moving them out with the other dust. This irritates the tissue causing the effects of the first answer. So it is a matter of time and number of asbestos particles that increases the probability of a cancer. Decades ago , the asbestos miners in Africa typically worked for years ( eg 20 years) before getting cancer.
There are basically three hypotheses regarding the pathogenesis of asbestos-induced cancer , which may be summarized as follows:
(1) the "oxidative stress theory" is based on the fact that phagocytic cells that engulf asbestos fibers produce large amounts of free radicals due to their inability to digest the fibers, and epidemiological studies indicating that iron-containing asbestos fibers appear more carcinogenic;
(2) the "chromosome tangling theory" postulates that asbestos fibers damage chromosomes when cells divide; and
(3) the "theory of adsorption of many specific proteins as well as carcinogenic molecules" states that asbestos fibers in vivo concentrate proteins or chemicals including the components of cigarette smoke.
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