Asbestos is a naturally occurring fibrous silicate mineral that was commercially exploited for its useful properties. There are over 3000 products containing asbestos that are around us today which includes insulation (thermal and acoustic) fire resistance and as a binder in cement.
The three main types of asbestos:
Chrysotile-(MgSiO) also known as lizardite and white asbestos.
Amosite-(FeMgSiO) also known as grunerite and brown asbestos.
Crocidolite-(NaFeSiO) also known as riebeckite and blue asbestos.
Diseases
As the latency period(the time between first exposure and death) is between 15 and 60 years many of the people who are dying from asbestos related diseases now were exposed in the 1960s and 1970s. Asbestos related diseases cause an estimated 3000 deaths per year.
Asbestosis, pleural plaques, lung cancer and mesothelioma are all caused by exposure to asbestos fibres.
A Brief History of Asbestos
- The word asbestos originates from around 4000BC (from the Greek meaning unquenchable). During this period it was used for wicks in candles & lamps.
- Around 2500BC asbestos was used to wrap around Egyptian pharaohs to offset the decomposing process. About the same time evidence shows it was used in Finland to give clay pots added strength.
- By 1000AD asbestos was being widely used for cremation cloths, mats & temple lamp wicks by the Mediterranean.
- During the early 1700s, the first asbestos paper & boards were made (Italy).
- In the mid 19th-century asbestos helmets & jackets were being worn by firefighters in France & insulation, packing’s& gaskets were being made from asbestos.
- It was during the 1870s the asbestos industry really took off with the founding of large asbestos companies in England, Scotland & Germany. Also in Russia & Canada where large deposits of chrysotile (white asbestos) were exploited.
- As long ago as 1897 the first bronchial problems were identified.
- During the first quarter of the 20th century, the first asbestos pipes & corrugated sheeting arrived on the scene.
- In 1931 the Asbestos regulations were passed in the U. K.
- Asbestos was beginning to crop up everywhere. In the 1939 film “The wizard of oz” the wicked witch of the West’s broom was made out of asbestos.
- Fireproof suits & parachute flares in WW11 were asbestos based.
- The post-war rebuilding & construction projects placed heavy reliance on asbestos & its usage reached an all-time high in 1973. From the mid 1970s, its use in new products declined rapidly. In 2003 the selling & fixing of asbestos-containing materials (ACM) in Australia was banned.
- A conservative estimate puts the amount of Asbestos still in Australian buildings at over 1 million tonnes