Asbestos is formed in fibre bundles and, as it is further processed or disturbed the fibre bundles become progressively finer and more hazardous to health. The small fibres are the most dangerous.

They are invisible to the naked eye and, when inhaled, penetrate the deepest part of the lungs (respirable fibres). Significant health risks may arise from the inhalation of airborne asbestos fibres. Amphibole fibres, such as Amosite and Crocidolite, Chrysotile fibres are curly and less likely to penetrate the deepest parts of the lung.

Exposure

Breathing in fibres brings a risk of asbestosis, lung cancer and Mesothelioma. Evidence suggests that asbestos causes gastrointestinal and laryngeal cancers in humans, but to a far lesser extent than lung cancer. Usually, asbestos-related diseases have a delay or latency period of 20 to 40 years between first exposure and the onset of symptoms and detection of the disease. Also note that asbestos-related diseases can appear or progress even after a person is no longer exposed.

Asbestos cancer

Impacts

Asbestosis is the scarring of lung tissue that can result from the inhalation of substantial amounts of asbestos over a period of years. Lung cancer is related to the amount of fibre that is breathed in and the risk of lung cancer is greatly increased in those who also smoke tobacco. Mesothelioma is a cancer of the pleura (outer lung lining) or the peritoneum (the lining of the abdominal cavity). The risk of esothelioma is less with Chrysotilethan with other types of asbestos. Both pleural and peritoneal Mesothelioma can result from exposure to Amosite and Crocidolite. Exposure of humans to Chrysotile alone has caused few pleural Mesothelioma, and has never produced peritoneal Mesothelioma without exposure to either Amosite or Crocidolite. Mesothelioma rarely occurs in less than 15 years from first exposure.

Advice

The asbestos fibre in the air that people inhale is the important factor in determining the level of health risk. The highest risks involves inhaling air that contains a high concentration of asbestos fibre.