What is asbestos?

History of asbestos

Asbestos has been used since ancient times: in Finland as early as 2500 BC in pottery, as wicks in oil lamps by the Vestal Virgins in ancient Rome, and for burial cloths in ancient Egypt. In ancient Greece, both the geologist Strabo and the author Pliny wrote of the heat-resistant qualities of asbestos-containing fabrics; they both also noted that the slaves required to weave asbestos cloth developed lung problems.

Asbestos use declined during the Middle Ages, although King Charlemagne is said to have had a tablecloth made from it (which he reportedly cleaned by throwing it into the fire), and Marco Polo was shown fire-resistant cloth woven from asbestos in his travels to China. Peter the Great of Russia is thought to have begun the production of asbestos paper at the end of the 17th century.

Commercial production began early in the 19th century in Italy, with the manufacture of asbestos textiles. Asbestos grew back in favour with the advent of the Industrial Revolution in the 19th century and its associated mechanization, when it was taken commercially in open pit mines. By the beginning of the 20th century it was a common component in many products that might catch fire, including theater curtains, buildings, boilers, steam engines and brake linings. Its widespread use in a huge variety of industrial applications mushroomed until the 1970s, especially for insulation and pipe wrapping and in construction -- but also in a wide array of domestic products (see Consumer products).

Throughout the 1930s, the association of asbestos and lung disease was well known by both asbestos manufacturers and their insurers, to the extent that the use of asbestos was in decline by the start of World War II. However, its production grew hugely during the war for use in ships, and continued to grow over the next 3 decades.

In 1960, the first series of asbestos-related malignant mesotheliomas was reported in 33 workers in a South African crocidolite mine. Other reports followed linking asbestos to malignant mesothelioma amongst pipe fitters in the USA; other reports followed from around the world. Asbestos was classified as a carcinogen in 1977 by the International Agency for Research on Cancer.

Use of asbestos stabilized after 1976 (the year of peak production), decreasing only in the late 1980s as its associated health risks became a matter of increasing public concern. Although in the USA the last domestic mine closed in 2002, asbestos is still imported here (6000 metric tons in 2003), mostly from Canada. Asbestos (predominantly chrysotile) is still widely mined outside the USA, especially in Russia (39%), Canada (18%), China (14%), Brazil (9%), Kazakhstan (7%), and Zimbabwe (6%).