One of the first descriptions of a material that may have been asbestos is in Theophrastus, On Stones, from around 300 BC, although this identification has been questioned. Early references and uses Īsbestos use dates back at least 4,500 years, when the inhabitants of the Lake Juojärvi region in East Finland strengthened earthenware pots and cooking utensils with the asbestos mineral anthophyllite (see Asbestos-ceramic).
Today people recognize the health hazard that asbestos poses the use of asbestos is completely banned in 66 countries and strictly regulated in many others. People have used asbestos for thousands of years to create flexible objects that resist fire, including napkins, but, in the modern era, companies began producing consumer goods containing asbestos on an industrial scale. ( May 2016) ( Learn how and when to remove this template message)
Unsourced material may be challenged and removed. Please help improve this article by adding citations to reliable sources in this section. This section needs additional citations for verification. The word is pronounced / æ s ˈ b ɛ s t ə s/ or / æ s ˈ b ɛ s t ɒ s/. It had also been called "amiant" in English in the early 15th century, but this usage was superseded by "asbestos". This is the source for the word for asbestos in many languages, such as the Portuguese amianto and the French amiante. Asbestos was referred to in Greek as amiantos, meaning "undefiled", because it was not marked when thrown into a fire. It is said by the Oxford English Dictionary to have been wrongly used by Pliny for asbestos, who popularized the misnomer. It was adopted into English via the Old French abestos, which in turn got the word from Greek via Latin, but in the original Greek, it actually referred to quicklime. The name reflects use of the substance for wicks that would never burn up. The word "asbestos", first used in the 1600s, ultimately derives from the Ancient Greek: ἄσβεστος, meaning "unquenchable" or "inextinguishable".
Many developing countries still support the use of asbestos as a building material, and mining of asbestos is ongoing, with the top producer, Russia, having an estimated production of 790,000 tonnes in 2020. The most common diseases associated with chronic asbestos exposure are asbestosis (scarring of the lungs due to asbestos inhalation) and mesothelioma (a type of cancer). The latency period (from exposure to the diagnosis of negative health effects) is typically 20 years. In part, this is because many older buildings still contain asbestos in addition, the consequences of exposure can take decades to arise. Despite this, at least 100,000 people are thought to die each year from diseases related to asbestos exposure. The use of asbestos for construction and fireproofing has been made illegal in many countries. Many buildings constructed before the 1980s contain asbestos. Asbestos is an excellent thermal and electrical insulator, and is highly fire resistant, so for much of the 20th century, it was very commonly used across the world as a building material, until its adverse effects on human health were more widely acknowledged in the 1970s. Īrchaeological studies have found evidence of asbestos being used as far back as the Stone Age to strengthen ceramic pots, but large-scale mining began at the end of the 19th century when manufacturers and builders began using asbestos for its desirable physical properties.
As a result of these health effects, asbestos is considered a serious health and safety hazard. Inhalation of asbestos fibres can lead to various dangerous lung conditions, including mesothelioma, asbestosis, and lung cancer. There are six types, all of which are composed of long and thin fibrous crystals, each fibre ( particulate with length substantially greater than width) being composed of many microscopic "fibrils" that can be released into the atmosphere by abrasion and other processes. Asbestos ( / æ s ˈ b ɛ s t ə s, æ z ˈ-, - t ɒ s/ ass- BEST-əs, az-, -oss) is a naturally occurring fibrous silicate mineral.
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