Asbestos (from Greek ἄσβεστος or asbestinon, meaning "unquenchable" or "inextinguishable") is a set of six naturally occurring silicate minerals exploited commercially for their desirable physical properties. They all have in common their asbestiform habit, long, thin fibrous crystals. The inhalation of asbestos fibers can cause serious illnesses, including malignant lung cancer, mesothelioma (a type of cancer strongly associated with exposure to amphibole asbestos), and asbestosis (a type of pneumoconiosis). Long exposure to high concentrations of asbestos fibers is more likely to cause health problems, as asbestos exists in the ambient air at low levels, which itself does not cause health problems. The European Union has banned all use of asbestos and extraction, manufacture and processing of asbestos products.
Asbestos became increasingly popular among manufacturers and builders in the late 19th century because of its sound absorption, average tensile strength, and its resistance to heat, electrical and chemical damage. When asbestos is used for its resistance to fire or heat, the fibers are often mixed with cement or woven into fabric or mats. Asbestos was used in some products for its heat resistance, and in the past was used on electric oven and hotplate wiring for its electrical insulation at elevated temperature, and in buildings for its flame-retardant and insulating properties, tensile strength, flexibility, and resistance to chemicals.
Worldwide, at least 90 000 people die every year from illnesses resulting from occupational exposure to asbestos. However, this number only takes into account workers and ex-workers who have been identified with asbestos-related lung cancer, mesothelioma, and asbestosis. But asbestos has also been linked to laryngeal and ovarian cancer. Factor in asbestos-related illness among individuals whose work history has not been recorded, the family members of those who work with asbestos, and people living near asbestos factories and mines, and the death toll is much higher.The lengthy latency period of asbestos-related malignant diseases—in some cases more than 40 years—means that even in countries that no longer use the material, the disease burden continues to rise. The
All of which has prompted more than 40 countries—including all member states of the European Union—to ban chrysotile. The World Bank has determined not to use it in any new development projects; and WHO has noted that “the most efficient way to eliminate asbestos-related disease is to stop using all types of asbestos”.
Nevertheless, about 125 million people across the globe are exposed to Asbestos in their working environment. Worldwide production remains at roughly the same level as in 1960: nearly 2·2 million metric tonnes per year. Vast development projects in
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