Asbestos is not one mineral, it is a set of six silicate fibres of amphibole and serpentine groups, of which chrysotile is one form. Chrystotile is different from Chrysolite. Chrysotile asbestos, along with five other forms of asbestos, together constitute asbestos.
Chrysotile, commonly known as white asbestos, is available in abundance and it is a commercial form of asbestos. It belongs to the serpentine asbestisoform minerals. Of all the six types of asbestos, Chrysotile is found the most. It is a contaminant or a phyllosilicate mineral, meaning that it has either a water molecule or hydroxyl group in it. It is soft and fibrous.
The chemical formula of Chrysotile is Mg3(Si2O5)(OH)4), but the hydroxyl (OH) group may be substituted by halides or oxides. Also, the Mg (magnesium ion) may be replaced by iron. Chrysotile is resistant to strong bases.
Chrysotile asbestos has some good physical properties for which it is used on a large scale in Civil Engineering. Being serpentine, it has curly fibers that are not as easy to inhale as the fibers from the amphibole forms of asbestos that are needle-like. Chrysotile is given preference above all other forms of asbestos because it is more flexible than the other types and could be spun and woven into fabric-type products including insulation, clothing, rope, and a variety of other products used in daily life. It was also used in brake linings, floor and ceiling tiles, joint compound, and many items used inside houses. Today, it is used in cement products including shingles, sheets, and pipes. Because of these properties, chrysotile is used on a large scale in third-tier, developing countries.
Health Risks of Chrysotile Exposure –
Various science institutions consider Chrysotile to be a human carcinogen. Chrysotile exposure is associated with parenchymal asbestosis, pleural abnormalities, peritoneal mesothelioma, and lung cancer. In some scientific publications, epidemiologists have published peer reviewed scientific research papers maintaining that chrysotile is the main cause of pleural mesothelioma. Although Chrysotile causes pleural mesothelioma and other asbestos-related diseases, it is not the most dangerous form of asbestos.
Chrysotile asbestos has been recommended for inclusion in the Rotterdam Convention on Prior Informed Consent, an international treaty that restricts trade of certain hazardous substances.
Canada is a major exporter of Chrysotile, the mineral being found at Quebec.
Images by John Betts – Fine Minerals.
Other countries that mine Chrysotile asbestos mineral are Russia and Italy. It is also found in the Kadapa district of Andhra Pradesh, India.