Under normal conditions, asbestos will last for centuries. Asbestos is a silicate, and derives from rock.
People tend to think of asbestos fibres as being the same composition as cotton or wool fibres, but it is a rock that has a crystal structure, that forms in the shape of long filaments. These filaments can be spun into thread and woven into cloth and cement; it is the materials that the asbestos fibres are spun in to that eventually disintegrate over time.
Asbestos is dangerous when it is damaged or deteriorates
When the material containing the asbestos fibres becomes friable (disintegrates) this is when the minute asbestos fibres are released and become airborne, hence – this is when they can be inhaled into the lungs. As a rule – the bodies natural defences will cough up foreign bodies, if not – cleared up by macrophages.
Clinical studies have shown that some asbestos fibres such as chrysotile, are resistant to macrophage clearance and this is when they become harmful
The silicate composition in the fibres can have an inflammatory response on human tissue – leading to the disruption of normal cells – hence leading to abnormal cell growth and cancer. The rare cancer ‘mesothelioma’ is predominantly linked to long exposure to asbestos inhalation.
So asbestos is virtually indestructible?
Yes – Some people assume that they can burn asbestos materials – but this just releases the left over asbestos fibres into the air. The safest way to dispose of asbestos is to bury it, but this should only be done under licensed conditions, where the burial site will be carefully monitored. Any asbestos removal – such as from a public building should be safely removed by an asbestos abatement company only, as any scraping, drilling, tearing, sawing, or sanding of the asbestos material will cause it to release fibres, hence – be inhaled.