
What is asbestos?
Asbestos is the term given to the fibrous form of six naturally occurring silicate minerals as follows:
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chrysotile (white)
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amosite (brown)
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crocidolite (blue)
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tremolite
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anthophyllite
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actinolite
Of these chrysotile belongs to the serpentine group and the rest belonging to the amphibole group.
Asbestos was mined commercially predominantly for its fire resistant properties but also has useful properties like high tensile strength, flexibility, low thermal conductivity, resistant to chemical attack, as well as acoustic insulation. It could also be used as a cheap bulk filler in many items. Because of this it was used in thousands of different product types from floor tiles to pipe insulation.

Why is is dangerous?
Currently asbestos kills around 5000 people in the U.K. per year, which is more than people killed in road traffic accidents. Asbestos has the ability to split in to tiny microscopic respirable fibres that can become airborne and then inhaled through the mouth and nose. The carcinogenic fibres stay in the lungs where they cause –
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Pleural plaques – Where the tissue around the lung hardens and thickens which can then trap and compress part of the lung. It often has no symptoms but can show up on x-ray’s.
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Pleural effusion – Build-up of excess fluid on the pleural space.
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Asbestosis – This is usually associated with heavy exposure to asbestos over prolonged periods. The fibres cause scarring on the lungs and in turn they become less elastic making it harder to breath.
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Lung cancer – This type of cancer forms in the lung tissue, usually in the cells lining the air passage.
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Mesothelioma – This is cancer of the pleura which can be related to low exposure to asbestos.
There have been some reported cases where cancers of the intestinal tract have also been linked to ingestion of asbestos fibres.