This publication is licensed under the terms of the Open Government Licence v3. To view this licence, visit nationalarchives. Where we have identified any third party copyright information you will need to obtain permission from the copyright holders concerned. Asbestos is a general name given to several naturally occurring fibrous minerals that have crystallised to form fibres. Asbestos fibres do not dissolve in water or evaporate, they are resistant to heat, fire, chemical and biological degradation and are mechanically strong.
Asbestos is generally divided into two sub-groups; serpentine and amphiboles. Serpentine asbestos chrysotile or white asbestos was the most commonly used type of asbestos. Chrysotile asbestos fibres are soft, flexible and curved and far less hazardous than the amphibole type. Amphibole fibres crocidolite -blue asbestos, amosite- brown asbestos, tremolite, actinolite and anthophyllite are brittle fibres and are often rod- or needle-like in appearance. It is this form that is more hazardous to health.
Crocidolite was the most commonly used amphibole asbestos in the past. The properties of asbestos made it an ideal material for use in a number of products, including insulation material for buildings, boilers and pipes; car brakes and floor tiles, insulating board to protect buildings and ships against fire; asbestos cement for roofing sheets and pipes. Due to the risks to health following inhalation exposure to asbestos the importation of blue and brown asbestos has been banned in the UK since This ban was extended to include white asbestos in Asbestos is widespread in the environment.
It may enter the atmosphere due to the natural weathering of asbestos-containing ores or damage and breakdown of asbestos-containing products including insulation, car brakes and clutches, ceiling and floor tiles and cement. People may come into contact with asbestos from existing asbestos-containing materials in buildings and products. If they are intact, they pose very little risk. However, if asbestos containing products are damaged in some way, fibres may be released.
Caution should be taken when doing DIY work in buildings containing asbestos. Find further advice on asbestos in the home People are most likely to be exposed to asbestos fibres by breathing in fibres that are suspended in air. People also may swallow small amounts of the fibres if the asbestos enters the soil or drinking water. Although asbestos does not dissolve, fibres may enter water after being eroded from natural sources, from asbestos-cement or from asbestos-containing filters.
However, there is no evidence the ingestion of asbestos fibres is hazardous to health. Those involved in demolition work, asbestos abatement, building repair and maintenance may be exposed to higher levels of asbestos as disturbing such materials releases fibres into the air. Intact asbestos materials in a place where they are unlikely to be disturbed should not cause any harm. Asbestos exposure may increase your risk for cancers of the digestive system, including colon cancer.
No amount of asbestos is considered safe. Products that contain greater than 1 percent of asbestos minerals are considered to be asbestos-containing. The more asbestos you are exposed to, the more likely you are to get an asbestos disease. Asbestosis and lung cancer are dose-related diseases. Dose-related means the more asbestos you breathe, the more likely you are to get sick.
The one asbestos disease that is different is mesothelioma. Very small amounts of asbestos can give you mesothelioma. Asbestos workers' families have gotten mesothelioma from the dust the workers brought home on their clothes.
All of the asbestos diseases have a latency period. The latency period is the gap between the time you breathe asbestos and the time you start to feel sick. The latency period for asbestos diseases is between 10 to 40 years. You will not feel sick during the latency period. If you get an asbestos disease, you will begin to feel sick after the latency period. Not everyone exposed to asbestos gets an asbestos disease. However, anyone exposed to asbestos has a higher risk of getting an asbestos disease.
Like other asbestos in the amphibole family, tremolite has sharp fibers that can easily be inhaled or ingested. Tremolite is no longer mined and is responsible for many cases of asbestos-related cancer and asbestos diseases. Tremolite ranges in color from a milky white to a dark green and is found in other minerals such as talc and vermiculite. Tremolite was previously used in a variety of products such as paint, sealants, insulation, roofing and plumbing materials.
Chrysotile asbestos is the only known type of asbestos that belongs to the serpentine family. Also known as white asbestos, this variety is made up of curly fibers and has a layered structure. Still mined today in Canada, Russia and Italy, there is continuing controversy between health care professionals and the companies that continue to export it.
These companies claim that the chrysotile mined today is safe because it is only used in dense and non-friable products and is "encapsulated in a matrix of either cement or resin. Because it is the most widely used, chrysotile accounts for the majority of cases of mesothelioma and asbestos diseases including pleural mesothelioma. Proton therapy is a non—invasive, incredibly precise cancer treatment that uses a beam of protons moving at very high speeds to destroy cancer cells.
Our experienced cancer nurses and referral staff are here to help. Call PENN or complete an online request. In This Section. What is Mesothelioma? Asbestos Cancer.
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