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Ch.4. Asbestos in the Environment . Introduction Properties and uses Brief history Environmental hazards. Introduction Asbestos : asbestoz “ inquenchable ” “inextinguishable” Fibrous silicate minerals: s erpentine & amphiboles White, brown, blue & others. crocidolite. chrysotile.
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Ch.4. Asbestos in the Environment • Introduction • Properties and uses • Brief history • Environmental hazards
Introduction • Asbestos: asbestoz“inquenchable” “inextinguishable” • Fibrous silicate minerals: serpentine & amphiboles • White, brown, blue & others crocidolite chrysotile Asbestos fibre tremolite From http://en.wikipedia.org/wiki/Asbestos
Properties & Use • Properties: • Mineral: insulation (heat, electricity), resistance against fire & chemical reaction, incombustibility • Fibre: flexibility, capability of being woven, sound-absorbing • Uses • (See the table on the next page)
Brief History • B.C. ca. 3,000 Scandinavian remains – used in porcelain and filler among the logs • 1C : Greek island Evvoia – Asbestos mining querry • Early Greek-Roman: unflammable clothes and building materials • Pliny the Elder: Thought to be used for the protection from the curse Pliny the Elder (23-79), a.k.a. Caius Plinius Secundus, Gaius Plinius Secundis. Author of the grand encyclopedia "Naturalis Historiae".
Ancient Egyptian: Used for Parao’s mummy • Ancient Persian: Imported from China, Used for the cloths for deaths, thought as feather of saramanda (phoenix) • Others: Lamp wick of tomb, Cure for itching Saramanda on a tile from ancient Iranian heritage http://www.metmuseum.org
Marco Polo (1254-1324): “Livres des merveilles du monde” Clothes being cleaned in fire?
In medieval times, asbestos was frequently used for the insulation of armor • Some fraud merchants made cross with asbestos and deceive people with it as if that was a part of the cross on which Jesus Christ was nailed (hung, executed)
19C: Industrial revolution also trigger modern application of asbestos • Used as heat insulator in USA & Canada in 1860’s • First commercial asbestos mine in Quebec, Canada, in 1879. • 20C: rapid increase of asbestos consumption • After 1970’s: Health threats (hazards) by asbestos became obvious invoke lot of regulations against asbestos usage. Ban of asbestos usgae Sudden decrease of asbestos consumption
Asbestos production and consumption Global production (10,000 ton/year) Japan (ton/year) China Korea
Now, the usage of asbestos is banned or limited in most countries • For Korea, • From 2009.09, asbestos is banned to be used in any industrial product • From 2007.07, any product containing asbestos is banned to import, produce, or use.