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Asbestos

Asbestos

Overview




Asbestos is a set of six naturally occurring silicate minerals
Silicate minerals
The silicate minerals make up the largest and most important class of rock-forming minerals, constituting approximately 90 percent of the crust of the Earth. They are classified based on the structure of their silicate group...

 used commercially for their desirable physical properties. They all have in common their eponymous, asbestiform habit: long, (1:20) thin fibrous crystal
Crystal
A crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions. The scientific study of crystals and crystal formation is known as crystallography...

s. The inhalation
Inhalation
Inhalation is the movement of air from the external environment, through the air ways, and into the alveoli....

 of asbestos fibers
Asbestos fibers
Asbestos fibers are released from asbestos containing materials . Friable asbestos containing materials release fibers more readily than encapsulated asbestos containing materials.- Determining airborne asbestos fiber levels :...

 can cause serious illnesses, including malignant lung cancer
Lung cancer
Lung cancer is a disease characterized by uncontrolled cell growth in tissues of the lung. If left untreated, this growth can spread beyond the lung in a process called metastasis into nearby tissue and, eventually, into other parts of the body. Most cancers that start in lung, known as primary...

, mesothelioma
Mesothelioma
Mesothelioma, more precisely malignant mesothelioma, is a rare form of cancer that develops from the protective lining that covers many of the body's internal organs, the mesothelium...

 (a formerly rare cancer
Cancer
Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...

 strongly associated with exposure to amphibole asbestos), and asbestosis
Asbestosis
Asbestosis is a chronic inflammatory and fibrotic medical condition affecting the parenchymal tissue of the lungs caused by the inhalation and retention of asbestos fibers...

 (a type of pneumoconiosis
Pneumoconiosis
Pneumoconiosis is an occupational lung disease and a restrictive lung disease caused by the inhalation of dust, often in mines.-Types:Depending upon the type of dust, the disease is given different names:...

).
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Encyclopedia




Asbestos is a set of six naturally occurring silicate minerals
Silicate minerals
The silicate minerals make up the largest and most important class of rock-forming minerals, constituting approximately 90 percent of the crust of the Earth. They are classified based on the structure of their silicate group...

 used commercially for their desirable physical properties. They all have in common their eponymous, asbestiform habit: long, (1:20) thin fibrous crystal
Crystal
A crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions. The scientific study of crystals and crystal formation is known as crystallography...

s. The inhalation
Inhalation
Inhalation is the movement of air from the external environment, through the air ways, and into the alveoli....

 of asbestos fibers
Asbestos fibers
Asbestos fibers are released from asbestos containing materials . Friable asbestos containing materials release fibers more readily than encapsulated asbestos containing materials.- Determining airborne asbestos fiber levels :...

 can cause serious illnesses, including malignant lung cancer
Lung cancer
Lung cancer is a disease characterized by uncontrolled cell growth in tissues of the lung. If left untreated, this growth can spread beyond the lung in a process called metastasis into nearby tissue and, eventually, into other parts of the body. Most cancers that start in lung, known as primary...

, mesothelioma
Mesothelioma
Mesothelioma, more precisely malignant mesothelioma, is a rare form of cancer that develops from the protective lining that covers many of the body's internal organs, the mesothelium...

 (a formerly rare cancer
Cancer
Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...

 strongly associated with exposure to amphibole asbestos), and asbestosis
Asbestosis
Asbestosis is a chronic inflammatory and fibrotic medical condition affecting the parenchymal tissue of the lungs caused by the inhalation and retention of asbestos fibers...

 (a type of pneumoconiosis
Pneumoconiosis
Pneumoconiosis is an occupational lung disease and a restrictive lung disease caused by the inhalation of dust, often in mines.-Types:Depending upon the type of dust, the disease is given different names:...

). Long exposure to high concentrations of asbestos fibers is more likely to cause health problems.This is most common among the miners of asbestos, since they have the longest exposure to it. The European Union
European Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...

 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
Tensile strength
Ultimate tensile strength , often shortened to tensile strength or ultimate strength, is the maximum stress that a material can withstand while being stretched or pulled before necking, which is when the specimen's cross-section starts to significantly contract...

, and its resistance to fire, heat, electrical and chemical damage. It was used in such applications as electrical insulation
Electrical insulation
thumb|250px|[[Coaxial Cable]] with dielectric insulator supporting a central coreThis article refers to electrical insulation. For insulation of heat, see Thermal insulation...

 for hotplate wiring and in building insulation
Building insulation
building insulation refers broadly to any object in a building used as insulation for any purpose. While the majority of insulation in buildings is for thermal purposes, the term also applies to acoustic insulation, fire insulation, and impact insulation...

. When asbestos is used for its resistance to fire or heat, the fibers are often mixed with cement
Cement
In the most general sense of the word, a cement is a binder, a substance that sets and hardens independently, and can bind other materials together. The word "cement" traces to the Romans, who used the term opus caementicium to describe masonry resembling modern concrete that was made from crushed...

 (resulting in fiber cement) or woven into fabric or mats. Commercial asbestos mining began in the Eastern Townships
Eastern Townships
The Eastern Townships is a tourist region and a former administrative region in south-eastern Quebec, lying between the former seigneuries south of the Saint Lawrence River and the United States border. Its northern boundary roughly followed Logan's Line, the geologic boundary between the flat,...

 of Quebec
Quebec
Quebec or is a province in east-central Canada. It is the only Canadian province with a predominantly French-speaking population and the only one whose sole official language is French at the provincial level....

, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

 and the world's largest asbestos mine is located in the town of Asbestos, Quebec
Asbestos, Quebec
-Communities:*Asbestos*Trois-Lacs-External links:***...

.

Types and associated fibers



Six minerals are defined by the United States Environmental Protection Agency
United States Environmental Protection Agency
The U.S. Environmental Protection Agency is an agency of the federal government of the United States charged with protecting human health and the environment, by writing and enforcing regulations based on laws passed by Congress...

 as "asbestos" including those belonging to the serpentine class chrysotile
Chrysotile
Chrysotile or white asbestos is the most commonly encountered form of asbestos, accounting for approximately 95% of the asbestos in place in the United States and a similar proportion in other countries. It is a soft, fibrous silicate mineral in the serpentine group of phyllosilicates; as such, it...

 and those belonging to the amphibole class amosite, crocidolite, tremolite
Tremolite
Tremolite is a member of the amphibole group of silicate minerals with composition: Ca2Mg5Si8O222. Tremolite forms by metamorphism of sediments rich in dolomite and quartz. Tremolite forms a series with actinolite and ferro-actinolite. Pure magnesium tremolite is creamy white, but the color grades...

, anthophyllite
Anthophyllite
Anthophyllite is an amphibole mineral: 7Si8O222, magnesium iron inosilicate hydroxide. Anthophyllite is polymorphic with cummingtonite. Some forms of anthophyllite are lamellar or fibrous and are used as asbestos...

 and actinolite
Actinolite
Actinolite is an amphibole silicate mineral with the chemical formula .-Etymology:The name actinolite is derived from the Greek word aktis , meaning "beam" or "ray", because of the mineral's fibrous nature...

. There is an important distinction to be made between serpentine and amphibole asbestos due to differences in their chemical composition and their degree of potency as a health hazard when inhaled. However asbestos and all commercial forms of asbestos (including chrysotile asbestos) are known to be human carcinogens based on sufficient evidence of carcinogenicity in humans.

White


Chrysotile
Chrysotile
Chrysotile or white asbestos is the most commonly encountered form of asbestos, accounting for approximately 95% of the asbestos in place in the United States and a similar proportion in other countries. It is a soft, fibrous silicate mineral in the serpentine group of phyllosilicates; as such, it...

, CAS No.
CAS registry number
CAS Registry Numbersare unique numerical identifiers assigned by the "Chemical Abstracts Service" toevery chemical described in the...

 12001-29-5, is obtained from serpentinite
Serpentinite
Serpentinite is a rock composed of one or more serpentine group minerals. Minerals in this group are formed by serpentinization, a hydration and metamorphic transformation of ultramafic rock from the Earth's mantle...

 rocks which are common throughout the world. Its idealized chemical formula
Chemical formula
A chemical formula or molecular formula is a way of expressing information about the atoms that constitute a particular chemical compound....

 is Mg
Magnesium
Magnesium is a chemical element with the symbol Mg, atomic number 12, and common oxidation number +2. It is an alkaline earth metal and the eighth most abundant element in the Earth's crust and ninth in the known universe as a whole...

(Si
Silicon
Silicon is a chemical element with the symbol Si and atomic number 14. A tetravalent metalloid, it is less reactive than its chemical analog carbon, the nonmetal directly above it in the periodic table, but more reactive than germanium, the metalloid directly below it in the table...

O
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...

)(OH
Hydroxide
Hydroxide is a diatomic anion with chemical formula OH−. It consists of an oxygen and a hydrogen atom held together by a covalent bond, and carrying a negative electric charge. It is an important but usually minor constituent of water. It functions as a base, as a ligand, a nucleophile, and a...

). Chrysotile fibers are curly as opposed to fibers from amosite, crocidolite, tremolite, actinolite, and anthophyllite which are needlelike. Chrysotile, along with other types of asbestos, has been banned in dozens of countries and is only allowed in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 and Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

 in very limited circumstances. Chrysotile has been used more than any other type and accounts for about 95% of the asbestos found in buildings in America. Applications where chrysotile might be used include the use of joint compound
Joint compound
Joint compound is a white substance similar to plaster used to seal joints between sheets of drywall, primarily in building construction. It is often referred to simply as mud.-Ready-mix lightweight joint compound:...

. It is more flexible than amphibole
Amphibole
Amphibole is the name of an important group of generally dark-colored rock-forming inosilicate minerals, composed of double chain tetrahedra, linked at the vertices and generally containing ions of iron and/or magnesium in their structures.-Mineralogy:...

 types of asbestos; it can be spun and woven into fabric
Fabric
A fabric is a textile material, short for "textile fabric".Fabric may also refer to:*Fabric , the spatial and geometric configuration of elements within a rock*Fabric , a nightclub in London, England...

. The most common use is within corrugated asbestos cement roof sheets typically used for outbuildings, warehouses and garages. It is also found as flat sheets used for ceilings and sometimes for walls and floors. Numerous other items have been made containing chrysotile including brake linings, cloth behind fuses (for fire protection), pipe insulation, floor tiles, and rope seals for boilers.

Brown


Amosite, CAS No. 12172-73-5, is a trade name
Trade name
A trade name, also known as a trading name or a business name, is the name which a business trades under for commercial purposes, although its registered, legal name, used for contracts and other formal situations, may be another....

 for the amphibole
Amphibole
Amphibole is the name of an important group of generally dark-colored rock-forming inosilicate minerals, composed of double chain tetrahedra, linked at the vertices and generally containing ions of iron and/or magnesium in their structures.-Mineralogy:...

s belonging to the cummingtonite
Cummingtonite
Cummingtonite is a metamorphic amphibole with the chemical composition 7Si8O222, magnesium iron silicate hydroxide.Monoclinic cummingtonite is compositionally similar and polymorphic with orthorhombic anthophyllite, which is a much more common form of magnesium-rich amphibole, the latter being...

-grunerite
Grunerite
Grunerite is a mineral of the amphibole group of minerals with formula Fe7Si8O222. It is the iron endmember of the grunerite-cummingtonite series. It forms as fibrous, columnar or massive aggregates of crystals. The crystals are monoclinic prismatic. The luster is glassy to pearly with colors...

 solid solution
Solid solution
A solid solution is a solid-state solution of one or more solutes in a solvent. Such a mixture is considered a solution rather than a compound when the crystal structure of the solvent remains unchanged by addition of the solutes, and when the mixture remains in a single homogeneous phase...

 series, commonly from South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

, named as an acronym from Asbestos Mines of South Africa. One formula given for amosite is Fe
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

7Si8O22(OH)2. It is found most frequently as a fire retardant in thermal insulation products and ceiling tiles.

Blue


Crocidolite, CAS No. 12001-28-4 is an amphibole found primarily in southern Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...

, but also in Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

. It is the fibrous form of the amphibole riebeckite
Riebeckite
Riebeckite is a sodium-rich member of the amphibole group of silicate minerals, chemical formula [][Na2][32][2|Si8O22]. It forms a series with magnesioriebeckite. It crystallizes in the monoclinic system, usually as long prismatic crystals showing a diamond-shaped cross section, but also in...

. One formula given for crocidolite is Na
Sodium
Sodium is a chemical element with the symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal and is a member of the alkali metals; its only stable isotope is 23Na. It is an abundant element that exists in numerous minerals, most commonly as sodium chloride...

2Fe
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

2+3Fe3+2Si
Silicon
Silicon is a chemical element with the symbol Si and atomic number 14. A tetravalent metalloid, it is less reactive than its chemical analog carbon, the nonmetal directly above it in the periodic table, but more reactive than germanium, the metalloid directly below it in the table...

8O
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...

22(OH
Hydroxyl
A hydroxyl is a chemical group containing an oxygen atom covalently bonded with a hydrogen atom. In inorganic chemistry, the hydroxyl group is known as the hydroxide ion, and scientists and reference works generally use these different terms though they refer to the same chemical structure in...

)2.

Crocidolite commonly occurs as soft friable
Friability
Friability is the ability of a solid substance to be reduced to smaller pieces with little effort. The opposite of friable is indurated....

 fibers. Asbestiform
Asbestiform
Asbestiform implies a particular kind of fibrosity in which fibers have high tensile strength and flexibility....

 amphibole may also occur as soft friable fibers but some varieties such as amosite are commonly straighter. All forms of asbestos are fibrillar in that they are composed of fibers with breadths less than 1 micrometer
Micrometre
A micrometer , is by definition 1×10-6 of a meter .In plain English, it means one-millionth of a meter . Its unit symbol in the International System of Units is μm...

 that occur in bundles and have very great widths. Asbestos with particularly fine fibers is also referred to as "amianthus".
Amphiboles such as tremolite have a crystal
Crystal
A crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions. The scientific study of crystals and crystal formation is known as crystallography...

 structure
Structure
Structure is a fundamental, tangible or intangible notion referring to the recognition, observation, nature, and permanence of patterns and relationships of entities. This notion may itself be an object, such as a built structure, or an attribute, such as the structure of society...

 containing strongly bonded ribbonlike silicate
Silicate
A silicate is a compound containing a silicon bearing anion. The great majority of silicates are oxides, but hexafluorosilicate and other anions are also included. This article focuses mainly on the Si-O anions. Silicates comprise the majority of the earth's crust, as well as the other...

 anion polymer
Polymer
A polymer is a large molecule composed of repeating structural units. These subunits are typically connected by covalent chemical bonds...

s that extend the width of the crystal. Serpentine (chrysotile
Chrysotile
Chrysotile or white asbestos is the most commonly encountered form of asbestos, accounting for approximately 95% of the asbestos in place in the United States and a similar proportion in other countries. It is a soft, fibrous silicate mineral in the serpentine group of phyllosilicates; as such, it...

) has a sheetlike silicate anion which is bowed and which rolls up like a carpet to form the fiber.

Other materials


Other regulated asbestos minerals, such as tremolite asbestos, CAS No. 77536-68-6, Ca
Calcium
Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...

2Mg5Si8O22(OH)2; actinolite asbestos, CAS No. 77536-66-4, Ca2(Mg, Fe)5(Si8O22)(OH)2; and anthophyllite asbestos, CAS No. 77536-67-5, (Mg, Fe)7Si8O22(OH)2; are less commonly used industrially but can still be found in a variety of construction materials and insulation materials and have been reported in the past to occur in a few consumer products
Product (business)
In general, the product is defined as a "thing produced by labor or effort" or the "result of an act or a process", and stems from the verb produce, from the Latin prōdūce ' lead or bring forth'. Since 1575, the word "product" has referred to anything produced...

.

Other natural and not currently regulated asbestiform minerals, such as richterite
Richterite
Richterite is a sodium calcium magnesium silicate mineral belonging to the amphibole group. If iron replaces the magnesium within the structure of the mineral, it is called ferrorichterite; if fluorine replaces the hydroxyl, it is called fluororichterite. Richterite crystals are long and prismatic,...

, Na(CaNa)(Mg, Fe++)5(Si8O22)(OH)2, and winchite, (CaNa)Mg4(Al, Fe3+)(Si8O22)(OH)2, may be found as a contaminant in products such as the vermiculite
Vermiculite
Vermiculite is a natural mineral that expands with the application of heat. The expansion process is called exfoliation and it is routinely accomplished in purpose-designed commercial furnaces. Vermiculite is formed by weathering or hydrothermal alteration of biotite or phlogopite...

 containing zonolite insulation manufactured by W.R. Grace and Company. These minerals are thought to be no less harmful than tremolite, amosite, or crocidolite, but since they are not regulated, they are referred to as "asbestiform" rather than asbestos although may still be related to diseases and hazardous.

Producing nations



In 2009, 2 million tonne
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...

s of asbestos were mined worldwide. Russia was the largest producer with about 50% world share followed by China (14%), Brazil (12.5%), Kazakhstan (10.5%) and Canada (9%).

Early uses


Asbestos use in human culture dates back at least 4,500 years, when evidence shows that inhabitants of the Lake Juojärvi
Juojärvi
Juojärvi is a lake in Finland. It is considered as one of the cleanest lakes of the country. New Valamo monastery is located on the shore of Juojärvi....

 region in East Finland
Finland
Finland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...

 strengthened earthenware pots and cooking utensils with the asbestos mineral anthophyllite. The word asbestos comes from the ancient Greek
Ancient Greece
Ancient Greece is a civilization belonging to a period of Greek history that lasted from the Archaic period of the 8th to 6th centuries BC to the end of antiquity. Immediately following this period was the beginning of the Early Middle Ages and the Byzantine era. Included in Ancient Greece is the...

 ἄσβεστος, meaning "unquenchable" or "inextinguishable". One of the first careful descriptions of the material is attributed to Theophrastus
Theophrastus
Theophrastus , a Greek native of Eresos in Lesbos, was the successor to Aristotle in the Peripatetic school. He came to Athens at a young age, and initially studied in Plato's school. After Plato's death he attached himself to Aristotle. Aristotle bequeathed to Theophrastus his writings, and...

 in his text On Stones, around 300 BC, although the naming of minerals was not very consistent at that time (the more consistent name of this material in both modern and ancient Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...

 is amiantos (undefiled, pure) whence the names of it in other languages like French
French language
French is a Romance language spoken as a first language in France, the Romandy region in Switzerland, Wallonia and Brussels in Belgium, Monaco, the regions of Quebec and Acadia in Canada, and by various communities elsewhere. Second-language speakers of French are distributed throughout many parts...

 amiante; the modern Greek
Modern Greek
Modern Greek refers to the varieties of the Greek language spoken in the modern era. The beginning of the "modern" period of the language is often symbolically assigned to the fall of the Byzantine Empire in 1453, even though that date marks no clear linguistic boundary and many characteristic...

 word ἀσβεστος or ασβέστης stands consistently and solely for lime
Lime (mineral)
Lime is a general term for calcium-containing inorganic materials, in which carbonates, oxides and hydroxides predominate. Strictly speaking, lime is calcium oxide or calcium hydroxide. It is also the name for a single mineral of the CaO composition, occurring very rarely...

, not for the material known as asbestos in English). The term asbestos is traceable to Roman naturalist Pliny the Elder
Pliny the Elder
Gaius Plinius Secundus , better known as Pliny the Elder, was a Roman author, naturalist, and natural philosopher, as well as naval and army commander of the early Roman Empire, and personal friend of the emperor Vespasian...

's manuscript Natural History, and his use of the term asbestinon, meaning "unquenchable". While Pliny is popularly attributed with recognising the detrimental effects of asbestos on slaves, examination of primary sources shows that this is not so. Charlemagne
Charlemagne
Charlemagne was King of the Franks from 768 and Emperor of the Romans from 800 to his death in 814. He expanded the Frankish kingdom into an empire that incorporated much of Western and Central Europe. During his reign, he conquered Italy and was crowned by Pope Leo III on 25 December 800...

, the first Holy Roman Emperor
Holy Roman Emperor
The Holy Roman Emperor is a term used by historians to denote a medieval ruler who, as German King, had also received the title of "Emperor of the Romans" from the Pope...

 (800-814), is said to have had a tablecloth made of asbestos.

According to Tabari
Muhammad ibn Jarir al-Tabari
Abu Ja'far Muhammad ibn Jarir al-Tabari was a prominent and influential Sunni scholar and exegete of the Qur'an from Persia...

, one of the curious items belonging to Khosrow II Parviz, the great Sassanian king (r. 531-579), was a napkin that he cleaned by simply throwing it into fire. This is believed to be made of asbestos. (This is also mentioned in The New Encyclopædia Britannica, vol. 6, 2003, page 843). Wealthy Persian
Persian people
The Persian people are part of the Iranian peoples who speak the modern Persian language and closely akin Iranian dialects and languages. The origin of the ethnic Iranian/Persian peoples are traced to the Ancient Iranian peoples, who were part of the ancient Indo-Iranians and themselves part of...

s, who bought asbestos imported over the Hindu Kush
Hindu Kush
The Hindu Kush is an mountain range that stretches between central Afghanistan and northern Pakistan. The highest point in the Hindu Kush is Tirich Mir in the Chitral region of Khyber-Pakhtunkhwa, Pakistan.It is the westernmost extension of the Pamir Mountains, the Karakoram Range, and is a...

, amazed guests by cleaning the cloth by simply exposing it to fire. According to Biruni in his book of Gems, any cloths made of asbestos were called shostakeh. Some of the Persians believed the fiber was fur from an animal (named samandar
Salamander (legendary creature)
The salamander is an amphibian of the order Urodela. As with many real creatures, pre-modern authors often ascribed fantastic qualities to it , and in recent times some have come to identify a legendary salamander as a distinct concept from the real organism. This idea is most highly developed in...

) that lived in fire and died when exposed to water, hence the old mistaken myth that the salamander tolerated fire.

While traveling to Siberia
Siberia
Siberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...

, Marco Polo
Marco Polo
Marco Polo was a Venetian merchant traveler from the Venetian Republic whose travels are recorded in Il Milione, a book which did much to introduce Europeans to Central Asia and China. He learned about trading whilst his father and uncle, Niccolò and Maffeo, travelled through Asia and apparently...

 described being offered garments that could not burn. He was told that the wool was from the salamander
Salamander
Salamander is a common name of approximately 500 species of amphibians. They are typically characterized by a superficially lizard-like appearance, with their slender bodies, short noses, and long tails. All known fossils and extinct species fall under the order Caudata, while sometimes the extant...

, but did not accept this explanation. At last he was told that these garments were made from a mineral from the mountains, which contained threads just like wool.

Some archeologists believe that ancients made shrouds of asbestos, wherein they burned the bodies of their kings, in order to preserve only their ashes, and prevent their being mixed with those of wood or other combustible materials commonly used in funeral pyres.
Others assert that the ancients used asbestos to make perpetual wicks for sepulchral
Sepulchre
The rock-cut tombs in ancient Israel are a group of hundreds of rock-cut tombs constructed in Israel in ancient times. They were cut into the rock, sometimes with elaborate facades and multiple burial chambers. Some are free-standing, but most are caves. Each tomb typically belonged to a...

 or other lamps. In more recent centuries, asbestos was indeed used for this purpose. Although asbestos causes skin to itch upon contact, ancient literature
Ancient literature
The history of literature begins with the history of writing, in Bronze Age Mesopotamia and Ancient Egypt.Writing develops out of proto-literate sign systems by the 30th century BC, although the oldest literary texts that have come down to us are several centuries younger, dating to the 27th or...

 indicates that it was prescribed for diseases of the skin, and particularly for the itch. It is possible that they used the term asbestos for soapstone
Soapstone
Soapstone is a metamorphic rock, a talc-schist. It is largely composed of the mineral talc and is thus rich in magnesium. It is produced by dynamothermal metamorphism and metasomatism, which occurs in the areas where tectonic plates are subducted, changing rocks by heat and pressure, with influx...

, because the two terms have often been confused throughout history.

Industrial Era


The U.S. asbestos industry began in 1858 when fibrous anthophyllite was mined for use as asbestos insulation by the Johns Company, a predecessor to the current Johns Manville at a quarry at Ward's Hill on Staten Island, New York. Asbestos became more widespread during the industrial revolution; in 1866 it was used as insulation in the U.S. and Canada. Development of the first commercial asbestos mine began in 1874 in the Appalachian
Appalachian Mountains
The Appalachian Mountains #Whether the stressed vowel is or ,#Whether the "ch" is pronounced as a fricative or an affricate , and#Whether the final vowel is the monophthong or the diphthong .), often called the Appalachians, are a system of mountains in eastern North America. The Appalachians...

 foothills of Quebec
Quebec
Quebec or is a province in east-central Canada. It is the only Canadian province with a predominantly French-speaking population and the only one whose sole official language is French at the provincial level....

. By the mid 20th century uses included fire retardant coatings, concrete, bricks, pipes and fireplace cement, heat, fire, and acid resistant gaskets, pipe insulation, ceiling insulation, fireproof drywall, flooring, roofing, lawn furniture, and drywall joint compound.

Asbestos fibers were once used in automobile brake pads
Brake pads
Brake pads are a component of disk brakes used in automotive and other applications. Brake pads are steel backing plates with friction material bound to the surface that faces the disk brake rotor.- Function :...

, shoes, and clutch discs
Clutch
A clutch is a mechanical device which provides for the transmission of power from one component to another...

. Since the mid-1990s, a majority of brake pads, new or replacement, have been manufactured instead with linings made of ceramic, carbon, metallic and aramid fiber
Aramid
Aramid fibers are a class of heat-resistant and strong synthetic fibers. They are used in aerospace and military applications, for ballistic rated body armor fabric and ballistic composites, in bicycle tires, and as an asbestos substitute. The name is a portmanteau of "aromatic polyamide"...

 (Twaron
Twaron
Twaron is the brandname of Teijin Aramid for a para-aramid. It is a heat-resistant and strong synthetic fibre developed in the early 1970s by the Dutch company AKZO, division Enka, later Akzo Industrial Fibers. The research name of the para-aramid fibre was originally Fiber X, but it was soon...

 or Kevlar
Kevlar
Kevlar is the registered trademark for a para-aramid synthetic fiber, related to other aramids such as Nomex and Technora. Developed at DuPont in 1965, this high strength material was first commercially used in the early 1970s as a replacement for steel in racing tires...

—the same material used in bulletproof vest
Bulletproof vest
A ballistic vest, bulletproof vest or bullet-resistant vest is an item of personal armor that helps absorb the impact from firearm-fired projectiles and shrapnel from explosions, and is worn on the torso...

s).

Kent's
Kent (cigarette)
Kent is a brand of cigarettes. Kent's Micronite filter was introduced shortly after the publication of a series of articles in Reader's Digest in 1952 entitled "Cancer by the Carton", that scared American consumers into seeking out a filter brand at a time when most brands were filterless...

 filtered cigarette
Cigarette filter
A cigarette filter has the purpose of reducing the amount of smoke, tar, and fine particles inhaled during the combustion of a cigarette. Filters also reduce the harshness of the smoke and keep tobacco flakes out of the smoker's mouth.-History:...

 used crocidolite asbestos in its "Micronite" filter from 1952 to 1956.

Artificial Christmas snow, known as flocking, was previously made with asbestos.

In Japan, particularly after World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

, asbestos was used in the manufacture of ammonium sulfate
Ammonium sulfate
Ammonium sulfate , 2SO4, is an inorganic salt with a number of commercial uses. The most common use is as a soil fertilizer. It contains 21% nitrogen as ammonium cations, and 24% sulfur as sulfate anions...

 for purposes of rice production, sprayed upon the ceilings, iron skeletons, and walls of railroad cars and buildings (during the 1960s), and used for energy efficiency reasons as well. Production of asbestos in Japan peaked in 1974 and went through ups and downs until about 1990, when production began to drop severely.

Discovery of toxicity


The first documented death related to asbestos was in 1906. In the early 1900s researchers began to notice a large number of early deaths and lung problems in asbestos mining towns. The first diagnosis of asbestosis
Asbestosis
Asbestosis is a chronic inflammatory and fibrotic medical condition affecting the parenchymal tissue of the lungs caused by the inhalation and retention of asbestos fibers...

 was made in the UK in 1924. By the 1930s, the UK regulated ventilation and made asbestosis an excusable work related disease, about ten years sooner than the U.S. The term mesothelioma
Mesothelioma
Mesothelioma, more precisely malignant mesothelioma, is a rare form of cancer that develops from the protective lining that covers many of the body's internal organs, the mesothelium...

 was first used in medical literature in 1931; its association with asbestos was first noted sometime in the 1940s.

Approximately 100,000 people in the United States have died, or will die, from asbestos exposure related to ship building. In the Hampton Roads
Hampton Roads
Hampton Roads is the name for both a body of water and the Norfolk–Virginia Beach metropolitan area which surrounds it in southeastern Virginia, United States...

 area, a shipbuilding center, mesothelioma
Mesothelioma
Mesothelioma, more precisely malignant mesothelioma, is a rare form of cancer that develops from the protective lining that covers many of the body's internal organs, the mesothelium...

 occurrence is seven times the national rate. Thousands of tons of asbestos were used in World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

 ships to wrap the pipes, line the boilers, and cover engine and turbine parts. There were approximately 4.3 million shipyard workers in the United States during WWII; for every thousand workers about fourteen died of mesothelioma and an unknown number died from asbestosis
Asbestosis
Asbestosis is a chronic inflammatory and fibrotic medical condition affecting the parenchymal tissue of the lungs caused by the inhalation and retention of asbestos fibers...

.

The United States government and asbestos industry have been criticized for not acting quickly enough to inform the public of dangers, and to reduce public exposure. In the late 1970s court documents proved that asbestos industry officials knew of asbestos dangers since the 1930s and had concealed them from the public. A similar situation had arisen in the 1920s with the careless handling of radium and the ensuing scandal of the Radium Girls
Radium Girls
The Radium Girls were female factory workers who contracted radiation poisoning from painting watch dials with glow-in-the-dark paint at the United States Radium factory in Orange, New Jersey around 1917....

.

In Australia, asbestos was widely used in construction and other industries between 1945 and 1980. From the 1970s there was increasing concern about the dangers of asbestos and its use was phased out. Mining ceased in 1983. The use of asbestos was phased out in 1989 and banned entirely in Dec 2003. The dangers of asbestos are now well known in Australia and there is help and support for sufferers from asbestosis or mesothelioma.

Serpentine group


Serpentine minerals have a sheet or layered structure. Chrysotile is the only asbestos mineral in the serpentine group. In the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

, chrysotile has been the most commonly used type of asbestos. According to the U.S. EPA Asbestos Building Inspectors Manual, chrysotile accounts for approximately 95% of asbestos found in buildings in the United States. Chrysotile is often present in a wide variety of products and materials, including:
  • drywall and joint compound
  • plaster
  • gas mask filters pre 1960s
  • mud and texture coats
  • vinyl floor tiles, sheeting, adhesives
  • roofing tars, felts, siding, and shingles
  • "transite
    Transite
    Transite originated as trade name that The Johns-Manville Corporation created for a line of asbestos-cement products, including boards and pipes...

    " panels, siding, countertops, and pipes
  • popcorn ceiling
    Popcorn ceiling
    A popcorn ceiling, also known as an acoustic ceiling, is a term for a spray-on or paint-on ceiling treatment used from the late 1950s into the 1980s in residential construction. Cheaper than painting, it could be quickly and easily sprayed on in new construction and was also useful in masking...

    s, also known as acoustic ceilings
  • fireproofing
    Fireproofing
    Fireproofing, a passive fire protection measure, refers to the act of making materials or structures more resistant to fire, or to those materials themselves, or the act of applying such materials. Applying a certification listed fireproofing system to certain structures allows these to have a...

  • caulk
  • gasket
    Gasket
    thumb|sright|250px|Some seals and gaskets1. [[o-ring]]2. fiber [[Washer |washer]]3. paper gaskets4. [[cylinder head]] [[head gasket|gasket]]...

    s
  • packing, a system for sealing
    Seal (mechanical)
    A mechanical seal is a device which helps join systems or mechanisms together by preventing leakage , containing pressure, or excluding contamination...

     a rotating shaft
  • brake
    Brake
    A brake is a mechanical device which inhibits motion. Its opposite component is a clutch. The rest of this article is dedicated to various types of vehicular brakes....

     pads and shoes
  • clutch
    Clutch
    A clutch is a mechanical device which provides for the transmission of power from one component to another...

     plates
  • stage curtains
  • fire blankets
  • interior fire doors
  • fireproof clothing for firefighters
  • thermal pipe insulation
  • filters for removing fine particulates from chemicals, liquids and wine
    Wine
    Wine is an alcoholic beverage, made of fermented fruit juice, usually from grapes. The natural chemical balance of grapes lets them ferment without the addition of sugars, acids, enzymes, or other nutrients. Grape wine is produced by fermenting crushed grapes using various types of yeast. Yeast...

  • dental cast linings
  • HVAC flexible duct connectors
  • drilling fluid
    Drilling fluid
    In geotechnical engineering, drilling fluid is a fluid used to aid the drilling of boreholes into the earth. Often used while drilling oil and natural gas wells and on exploration drilling rigs, drilling fluids are also used for much simpler boreholes, such as water wells. Liquid drilling fluid...

     additives



In the European Union
European Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...

 and Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

 it has recently been banned as a potential health hazard and is not used at all. Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

 is moving in the same direction, but more slowly. Revelations that hundreds of workers had died in Japan over the previous few decades from diseases related to asbestos sparked a scandal in mid-2005. Tokyo had, in 1971, ordered companies handling asbestos to install ventilators and check health on a regular basis; however, the Japanese government did not ban crocidolite and amosite until 1995, and a full-fledged ban on asbestos was implemented in October 2004.

Amphibole group


Five types of asbestos are found in the amphibole group: amosite, crocidolite, anthophyllite, tremolite, and actinolite. Amosite, the second most likely type to be found in buildings, according to the U.S. EPA Asbestos Building Inspectors Guide, is the "brown" asbestos.

Amosite and crocidolite were formerly used in many products until the early 1980s. The use of all types of asbestos in the amphibole group was banned in much of the Western world by the mid-1980s, and by Japan in 1995. These products were mainly
  • Low density insulation board and ceiling tiles;
  • Asbestos-cement
    Eternit
    Eternit is the registered trademark for fibre cement. This has caused fibre cement to be known under the "Eternit" brand. Though, this is not to be confused, "Eternit" is only a trademark for fibre cement....

     sheets and pipes for construction, casing for water and electrical/telecommunication services;
  • Thermal and chemical insulation (e.g., fire rated doors, limpet spray, lagging and gaskets).

Health problems



Amosite and crocidolite are the most hazardous of the asbestos minerals because of their long persistence in the lungs of exposed people. Tremolite often contaminates chrysotile asbestos, thus creating an additional hazard. Chrysotile asbestos, like all other forms of asbestos, has produced tumors in animals. Mesothelioma
Mesothelioma
Mesothelioma, more precisely malignant mesothelioma, is a rare form of cancer that develops from the protective lining that covers many of the body's internal organs, the mesothelium...

s have been observed in people who were occupationally exposed to chrysotile, family members of the occupationally exposed, and residents who lived close to asbestos factories and mines. According to the NCI, "A history of asbestos exposure at work is reported in about 70 percent to 80 percent of all cases. However, mesothelioma has been reported in some individuals without any known exposure to asbestos." The most common diseases associated with chronic exposure to asbestos include: asbestosis and pleural abnormalities (mesothelioma, lung cancer).

Studies have shown an increased risk of lung cancer among smokers who are exposed to asbestos compared to nonsmokers. .

Asbestos exposure becomes a health concern when high concentrations of asbestos fibers are inhaled over a long time period. People who become ill from inhaling asbestos are often those who are exposed on a day-to-day basis in a job where they worked directly with the material. As a person's exposure to fibers increases, because of being exposed to higher concentrations of fibers and/or by being exposed for a longer time, then that person's risk of disease also increases. Disease is very unlikely to result from a single, high-level exposure, or from a short period of exposure to lower levels.

Mechanisms which might be triggering cancer development


Stanton and Layard concluded in 1977–78 that asbestos toxicity is not initiated by chemical effects, that is any trigger-effects of asbestos must presumably be physical, such as (A) mechanical damage or (B) unwanted signal channels (a plausible property for slender transparent fibres) which might disrupt normal cell activity—especially mitosis
Mitosis
Mitosis is the process by which a eukaryotic cell separates the chromosomes in its cell nucleus into two identical sets, in two separate nuclei. It is generally followed immediately by cytokinesis, which divides the nuclei, cytoplasm, organelles and cell membrane into two cells containing roughly...

.

(A) Mechanical Damage. There is experimental evidence that very slim fibers (<60 nm, <0.06 μm
in breadth) do tangle destructively with chromosomes (being of comparable size). Clearly that is likely to cause the sort of mitosis disruption expected in cancer.

(B) Unwanted Signal channels. This has recently been explored theoretically, but not yet experimentally. The theory argues that this effect would only be feasible for asbestos fibers >120 nm in breadth, which suggests that we should be on the look-out for a possible mixture of different mechanisms for the different fiber-diameter-ranges.

One popular idea of the causal chain is (1) Asbestos fiber → → (3) inflammation
Inflammation
Inflammation is part of the complex biological response of vascular tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. Inflammation is a protective attempt by the organism to remove the injurious stimuli and to initiate the healing process...

 → (4) other pathology. While that may be true, it does not explain "(2), the actual trigger":
"What is the physical property of asbestos which initiates any such inflammation?" (After all, inflammation is usually seen as caused by chemical-based processes: immunological &/or bacterial). So inflammation (&/or oxidation etc.) may well be part of the causal chain, but not the crucial first step.

Other asbestos-related diseases

  • Asbestosis
    Asbestosis
    Asbestosis is a chronic inflammatory and fibrotic medical condition affecting the parenchymal tissue of the lungs caused by the inhalation and retention of asbestos fibers...

    : Progressive fibrosis of the lungs of varying severity, progressing to bilateral fibrosis, honeycombing of the lungs on radiological view with symptoms including rales and wheezing.
  • Asbestos warts: caused when the sharp fibers lodge in the skin
    Skin
    -Dermis:The dermis is the layer of skin beneath the epidermis that consists of connective tissue and cushions the body from stress and strain. The dermis is tightly connected to the epidermis by a basement membrane. It also harbors many Mechanoreceptors that provide the sense of touch and heat...

     and are overgrown causing benign callus
    Callus
    A callus is an especially toughened area of skin which has become relatively thick and hard in response to repeated friction, pressure, or other irritation. Rubbing that is too frequent or forceful will cause blisters rather than allow calluses to form. Since repeated contact is required, calluses...

    -like growths.
  • Pleural plaques: discrete fibrous or partially calcified thickened area which can be seen on X-ray
    X-ray
    X-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 120 eV to 120 keV. They are shorter in wavelength than UV rays and longer than gamma...

    s of individuals exposed to asbestos. Although pleural plaques are themselves asymptomatic, in some patients this develops into pleural thickening.
  • Diffuse pleural thickening: similar to above and can sometimes be associated with asbestosis
    Asbestosis
    Asbestosis is a chronic inflammatory and fibrotic medical condition affecting the parenchymal tissue of the lungs caused by the inhalation and retention of asbestos fibers...

    . Usually no symptoms shown but if exposure is extensive, it can cause lung
    Lung
    The lung is the essential respiration organ in many air-breathing animals, including most tetrapods, a few fish and a few snails. In mammals and the more complex life forms, the two lungs are located near the backbone on either side of the heart...

     impairment.

Asbestos as a contaminant


Most respirable asbestos fibers are invisible to the unaided human eye
Human eye
The human eye is an organ which reacts to light for several purposes. As a conscious sense organ, the eye allows vision. Rod and cone cells in the retina allow conscious light perception and vision including color differentiation and the perception of depth...

 because their size is about 3–20 µm
Micrometre
A micrometer , is by definition 1×10-6 of a meter .In plain English, it means one-millionth of a meter . Its unit symbol in the International System of Units is μm...

 wide and can be as slim as 0.01 µm. Human hair ranges in size from 17 to 181 µm in breadth. Fibers ultimately form because when these minerals originally cooled and crystallized, they formed by the polymer
Polymer
A polymer is a large molecule composed of repeating structural units. These subunits are typically connected by covalent chemical bonds...

ic molecules lining up parallel with each other and forming oriented crystal lattices
Crystal structure
In mineralogy and crystallography, crystal structure is a unique arrangement of atoms or molecules in a crystalline liquid or solid. A crystal structure is composed of a pattern, a set of atoms arranged in a particular way, and a lattice exhibiting long-range order and symmetry...

. These crystals thus have three cleavage planes
Cleavage (crystal)
Cleavage, in mineralogy, is the tendency of crystalline materials to split along definite crystallographic structural planes. These planes of relative weakness are a result of the regular locations of atoms and ions in the crystal, which create smooth repeating surfaces that are visible both in the...

, and in this case, there are two cleavage planes which are much weaker than the third. When sufficient force is applied, they tend to break along their weakest directions, resulting in a linear fragmentation pattern and hence a fibrous form. This fracture process can keep occurring and one larger asbestos fiber can ultimately become the source of hundreds of much thinner and smaller fibers.

As asbestos fibers get smaller and lighter, they more easily become airborne and human respiratory exposures can result. Fibers will eventually settle but may be re-suspended by air currents or other movement.

Friability
Friability
Friability is the ability of a solid substance to be reduced to smaller pieces with little effort. The opposite of friable is indurated....

 of a product containing asbestos means that it is so soft and weak in structure that it can be broken with simple finger crushing pressure. Friable materials are of the most initial concern because of their ease of damage. The forces or conditions of usage that come into intimate contact with most non-friable materials containing asbestos are substantially higher than finger pressure.

Environmental asbestos


Asbestos can be found naturally in the air outdoors and in some drinkable water, including water from natural sources. Studies have shown that members of the general (non-occupationally exposed) population have tens of thousands to hundreds of thousands of asbestos fibers in each gram of dry lung tissue, which translates into millions of fibers and tens of thousands of asbestos bodies in every person's lungs.

Asbestos from natural geologic deposits is known as "naturally occurring asbestos" (NOA). Health risks associated with exposure to NOA are not yet fully understood, and current US federal regulations do not address exposure from NOA. Many populated areas are in proximity to shallow, natural deposits which occur in 50 of 58 California counties and in 19 other U.S. states. In one study, data was collected from 3,000 mesothelioma
Mesothelioma
Mesothelioma, more precisely malignant mesothelioma, is a rare form of cancer that develops from the protective lining that covers many of the body's internal organs, the mesothelium...

 patients in California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

 and 890 men with prostate cancer
Prostate cancer
Prostate cancer is a form of cancer that develops in the prostate, a gland in the male reproductive system. Most prostate cancers are slow growing; however, there are cases of aggressive prostate cancers. The cancer cells may metastasize from the prostate to other parts of the body, particularly...

, a malignancy not known to be related to asbestos. The study found a correlation between the incidence of mesotheliomas and the distance a patient lived from known deposits of rock likely to include asbestos; the correlation was not present when the incidence of prostate cancer was compared with the same distances. According to the study, risk of mesothelioma declined by 6% for every 10 km that an individual had lived away from a likely asbestos source.

Portions of El Dorado County, California
El Dorado County, California
El Dorado County is a county located in the historic Gold Country in the Sierra Nevada Mountains and foothills of the U.S. state of California. The 2010 population was 181,058. The El Dorado county seat is in Placerville....

 are known to contain natural amphibole asbestos formations at the surface. The USGS studied amphibole
Amphibole
Amphibole is the name of an important group of generally dark-colored rock-forming inosilicate minerals, composed of double chain tetrahedra, linked at the vertices and generally containing ions of iron and/or magnesium in their structures.-Mineralogy:...

s in rock and soil in the area in response to an EPA sampling study and subsequent criticism of the EPA study. The EPA study was refuted by its own peer reviewers and never completed or published. The study found that many amphibole particles in the area meet the counting rule criteria used by the EPA for chemical and morphological limits, but do not meet morphological requirements for commercial-grade-asbestos. The executive summary pointed out that even particles that do not meet requirements for commercial-grade-asbestos may be a health threat and suggested a collaborative research effort to assess health risks associated with "Naturally Occurring Asbestos."

However, the main criticism pointed at EPA was that their testing was conducted in small isolated areas of El Dorado where there were no amphibole asbestos deposits, thus the language regarding amphibole, nonfibrous "particles". Actual surface amphibole deposits in residential areas were ignored for testing purposes. Thus no final findings were published by ATSDR since the criticism was correct and the effort of combined EPA/ATSDR teams were wasted time and money.

Great deals of Fairfax County, Virginia
Fairfax County, Virginia
Fairfax County is a county in Virginia, in the United States. Per the 2010 Census, the population of the county is 1,081,726, making it the most populous jurisdiction in the Commonwealth of Virginia, with 13.5% of Virginia's population...

 were also found to be underlain with tremolite
Tremolite
Tremolite is a member of the amphibole group of silicate minerals with composition: Ca2Mg5Si8O222. Tremolite forms by metamorphism of sediments rich in dolomite and quartz. Tremolite forms a series with actinolite and ferro-actinolite. Pure magnesium tremolite is creamy white, but the color grades...

. The county monitored air quality at construction sites, controlled soil taken from affected areas, and required freshly developed sites to lay 6 inches (152.4 mm) of clean, stable material over the ground.

For environmental samples, one must normally resort to electron microscopy for positive identification.
Today, gravimetric and PCM
Phase contrast microscopy
Phase contrast microscopy is an optical microscopy illumination technique of great importance to biologists in which small phase shifts in the light passing through a transparent specimen are converted into amplitude or contrast changes in the image.A phase contrast microscope does not require...

/PLM
Polarized light microscopy
Polarized light microscopy can mean any of a number of optical microscopy techniques involving polarized light. Simple techniques include illumination of the sample with polarized light. Directly transmitted light can, optionally, be blocked with a polariser orientated at 90 degrees to the...

 techniques are employed. However, the latter techniques cannot readily identify the smallest, most hazardous, fibers, because they are limited to PM10 particulate size evaluation, which completely ignores ultrafine particles
Ultrafine particles
Ultrafine particles are nanoscale, less than 100 nanometres. Regulations do not exist for this size class of ambient air pollution particles, which are far smaller than the regulated PM10 and PM2.5 size classes and are believed to have several more aggressive health implications than those classes...

 (UFPs).

Until 1900


By the first century AD, Greeks and Romans are claimed to have observed that slaves involved in the weaving of asbestos cloth were afflicted with a sickness of the lungs, although this is not confirmed by examination of primary sources.

Early concern in the modern era on the health effects of asbestos exposure can be found in several sources. Among the earliest were reports in Britain. The annual reports of the Chief Inspector of Factories reported as early as 1898 that asbestos had "easily demonstrated" health risks.

At about the same time, what was probably the first study of mortality among asbestos workers was reported in France. While the study describes the cause of death as chalicosis
Chalicosis
Chalicosis , sometimes called Flint disease, is a form of pneumoconiosis affecting the lungs or bronchioles.It is found chiefly among stonecutters....

, a generalized pneumoconiosis
Pneumoconiosis
Pneumoconiosis is an occupational lung disease and a restrictive lung disease caused by the inhalation of dust, often in mines.-Types:Depending upon the type of dust, the disease is given different names:...

, the circumstances of the employment of the fifty workers whose death prompted the study suggest that the root cause was asbestos or mixed asbestos-cotton dust exposure.

1900s—1910s



Further awareness of asbestos-related diseases can be found in the early 1900s, when London doctor H. Montague Murray conducted a post mortem exam on a young asbestos factory worker who died in 1899. Dr. Murray gave testimony on this death in connection with an industrial disease compensation hearing. The post-mortem confirmed the presence of asbestos in the lung tissue, prompting Dr. Murray to express as an expert opinion his belief that the inhalation of asbestos dust had at least contributed to, if not actually caused, the death of the worker.

The record in the United States was similar. Early observations were largely anecdotal in nature and did not definitively link the occupation with the disease, followed by more compelling and larger studies that strengthened the association. One such study, published in 1918, noted:
All of these processes unquestionably involve a considerable dust hazard, but the hygienic aspects of the industry have not been reported upon. It may be said, in conclusion, that in the practice of American and Canadian life insurance companies, asbestos workers are generally declined on account of the assumed health-injurious conditions of the industry.

1920s—1930s


Widespread recognition of the occupational risks of asbestos in Britain was reported in 1924 by a Dr. Cooke, a pathologist, who introduced a case description of a 33-year-old female asbestos worker, Nellie Kershaw
Nellie Kershaw
Nellie Kershaw was an English textile worker from Rochdale, Greater Manchester. Her death due to pulmonary asbestosis was the first such case to be described in medical literature, and the first published account of disease attributed to occupational asbestos exposure...

, with the following: "Medical men in areas where asbestos is manufactured have long suspected the dust to be the cause of chronic bronchitis and fibrosis..." Dr. Cooke then went on to report on a case in 1927 involving a 33-year-old male worker who was the only survivor out of ten workers in an asbestos carding
Carding
Carding is a mechanical process that breaks up locks and unorganised clumps of fibre and then aligns the individual fibres so that they are more or less parallel with each other. The word is derived from the Latin carduus meaning teasel, as dried vegetable teasels were first used to comb the raw wool...

 room. In the report he named the disease "asbestosis".

Dr. Cooke's second case report was followed, in the late 1920s, by a large public health investigation (now known as the Merewether report after one of its two authors) that examined some 360 asbestos-textile workers (reported to be about 15% of the total comparable employment in Britain at the time) and found that about a quarter of them suffered from pulmonary fibrosis. This investigation resulted in improved regulation of the manufacturing of asbestos-containing products in the early 1930s. Regulations included industrial hygiene standards, medical examinations, and inclusion of the asbestos industry into the British Workers' Compensation Act.

The first known U.S. workers' compensation claim for asbestos disease was in 1927. In 1930, the first reported autopsy of an asbestosis sufferer was conducted in the United states and later presented by a doctor at the Mayo Clinic
Mayo Clinic
Mayo Clinic is a not-for-profit medical practice and medical research group specializing in treating difficult patients . Patients are referred to Mayo Clinic from across the U.S. and the world, and it is known for innovative and effective treatments. Mayo Clinic is known for being at the top of...

, although in this case the exposure involved mining activities somewhere in South America.

In 1930, the major asbestos company Johns-Manville produced a report, for internal company use only, about medical reports of asbestos worker fatalities. In 1932, a letter from U.S. Bureau of Mines to asbestos manufacturer Eagle-Picher
Eagle-Picher
Eagle-Picher Corporation is a privately held, American, manufacturing and resource extractive company known for its storage battery technology. It was founded in 1842 as a paint manufacturing firm using the name Eagle White Lead, and became Eagle-Picher Lead in 1916 with its merger with a lead...

 stated, in relevant part, "It is now known that asbestos dust is one of the most dangerous dusts to which man is exposed."

In 1933, Metropolitan Life Insurance Co. doctors found that 29% of workers in a Johns-Manville plant had asbestosis. Likewise, in 1933, Johns-Manville officials settled lawsuits by 11 employees with asbestosis on the condition that the employees' lawyer agree to never again "directly or indirectly participate in the bringing of new actions against the Corporation." In 1934, officials of two large asbestos companies, Johns-Manville and Raybestos-Manhattan, edited an article about the diseases of asbestos workers written by a Metropolitan Life Insurance Company doctor. The changes downplayed the danger of asbestos dust. In 1935, officials of Johns-Manville and Raybestos-Manhattan instructed the editor of Asbestos magazine to publish nothing about asbestosis. In 1936, a group of asbestos companies agreed to sponsor research on the health effects of asbestos dust, but required that the companies maintain complete control over the disclosure of the results.

1940s


In 1942, an internal Owens-Corning corporate memo referred to "medical literature on asbestosis… scores of publications in which the lung and skin hazards of asbestos are discussed." Testimony given in a federal court in 1984 by Charles H. Roemer, formerly an employee of Unarco, described a meeting in the early 1940s between Unarco officials, J-M President Lewis H. Brown
Lewis H. Brown
Lewis Herold Brown was an industrialist.-Early life and career:Born in Creston, Iowa on February 13, 1894, he attended the University of Iowa in 1915. Brown served in France as an infantry captain during World War I. After the war, Brown was employed by Montgomery Ward and was promoted to...

 and J-M attorney Vandiver Brown. Roemer stated, "I’ll never forget, I turned to Mr. Brown, one of the Browns made this crack (that Unarco managers were a bunch of fools for notifying employees who had asbestosis), and I said, ‘Mr. Brown, do you mean to tell me you would let them work until they dropped dead?’ He said, ‘Yes. We save a lot of money that way.'" In 1944, a Metropolitan Life Insurance Company report found 42 cases of asbestosis among 195 asbestos miners.

1950s


In 1951, asbestos companies removed all references to cancer before allowing publication of research they sponsored. In 1952, Dr. Kenneth Smith, Johns-Manville medical director, recommended (unsuccessfully) that warning labels be attached to products containing asbestos. Later, Smith testified: "It was a business decision as far as I could understand… the corporation is in business to provide jobs for people and make money for stockholders and they had to take into consideration the effects of everything they did and if the application of a caution label identifying a product as hazardous would cut into sales, there would be serious financial implications."

In 1953, National Gypsum's safety director wrote to the Indiana Division of Industrial Hygiene, recommending that acoustic plaster
Acoustic plaster
Acoustic plaster is plaster which contains fibres or aggregate so that it absorbs sound.Such plaster is applied in thicknesses of up to 1.5 inches. As compared with other sound insulation, it is easy to apply and is fireproof but it can be more fragile, being affected by physical stress and humidity...

 mixers wear respirators "because of the asbestos used in the product." Another company official noted that the letter was "full of dynamite" and urged that it be retrieved before reaching its destination. A memo in the files noted that the company "succeeded in stopping" the letter, which "will be modified."

1960s—1980s


Through the 1970s, asbestos was used to fireproof roofing and flooring, for heat insulation, and for a variety of other purposes. The material was used in fire-check partitioning and doors on North Sea Oil Production Platforms and Rigs.

United States


In 1989 the United States Environmental Protection Agency
United States Environmental Protection Agency
The U.S. Environmental Protection Agency is an agency of the federal government of the United States charged with protecting human health and the environment, by writing and enforcing regulations based on laws passed by Congress...

 (EPA) issued the Asbestos Ban and Phase Out Rule which was subsequently overturned in the case of Corrosion Proof Fittings v. EPA, 947 F.2d 1201 (5th Cir. 1991). This ruling leaves many consumer products that can still legally contain trace amounts of asbestos. For a clarification of products which legally contain asbestos, read the EPA's clarification statement.

The EPA has proposed a concentration limit of seven million fibers per liter of drinking water for long fibers (lengths greater than or equal to 5 µm). The Occupational Safety and Health Administration
Occupational Safety and Health Administration
The United States Occupational Safety and Health Administration is an agency of the United States Department of Labor. It was created by Congress of the United States under the Occupational Safety and Health Act, signed by President Richard M. Nixon, on December 29, 1970...

 (OSHA), has set limits of 100,000 fibers with lengths greater than or equal to 5 µm per cubic meter of workplace air for eight-hour shifts and 40-hour work weeks.

OSHA regulations regarding asbestos are covered in 29 C.F.R. 1926.1101. Such work is divided into four categories.

Class I asbestos work means activities involving the removal of TSI and surfacing ACM and PACM.

Class II asbestos work means activities involving the removal of ACM which is not thermal system insulation or surfacing material. This includes, but is not limited to, the removal of asbestos-containing wallboard, floor tile and sheeting, roofing and siding shingles, and construction mastics.

Class III asbestos work means repair and maintenance operations, where "ACM", including TSI and surfacing ACM and PACM, is likely to be disturbed.

Class IV asbestos work means maintenance and custodial activities during which employees contact but do not disturb ACM or PACM and activities to clean up dust, waste and debris resulting from Class I, II, and III activities.

New Zealand


In 1984, the import of raw amphibole (blue and brown) asbestos into New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...

 was banned. In 2002 the import of chrysotile (white) asbestos was banned.

Australia


A complete ban on asbestos-containing material in Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

 was introduced in 1991 although some building materials in storage were still being used in the years that followed. Queensland
Queensland
Queensland is a state of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory, South Australia and New South Wales to the west, south-west and south respectively. To the east, Queensland is bordered by the Coral Sea and Pacific Ocean...

 began regulation of asbestos removal and disposal in 2005. Handlers of asbestos materials must have a B-Class license for bonded asbestos and an A-Class license for friable asbestos.

The town of Wittenoom
Wittenoom, Western Australia
Wittenoom is a ghost town located 1,106 kilometres north-northeast of Perth in the Hamersley Range in the Pilbara region of Western Australia. It is the site of Australia's greatest industrial disaster....

, in Western Australia
Western Australia
Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...

 was built around a (blue) asbestos mine. The entire town continues to be contaminated, and has been degazetted, allowing local authorities to remove references to Wittenoom from maps and roadsigns.

Asbestos and vermiculite


Vermiculite
Vermiculite
Vermiculite is a natural mineral that expands with the application of heat. The expansion process is called exfoliation and it is routinely accomplished in purpose-designed commercial furnaces. Vermiculite is formed by weathering or hydrothermal alteration of biotite or phlogopite...

 is a hydrated laminar magnesium-aluminum-iron silicate which resembles mica
Mica
The mica group of sheet silicate minerals includes several closely related materials having highly perfect basal cleavage. All are monoclinic, with a tendency towards pseudohexagonal crystals, and are similar in chemical composition...

. It can be used for many industrial applications and has been used as a replacement for asbestos. Some ore bodies of vermiculite have been found to contain small amounts of asbestos. One vermiculite mine operated by W. R. Grace and Company
W. R. Grace and Company
W. R. Grace and Company is a Columbia, Maryland, United States based chemical conglomerate.The company has two main divisions, Davison Chemicals and Performance Chemicals. The Davison unit makes chemical catalysts, refining catalysts, and silica-based products that let other companies make...

 in Libby, Montana
Libby, Montana
Libby is a city in and the county seat of Lincoln County, Montana, United States. The population was 2,626 at the 2000 census.-Geography:Libby is located at , along U.S. Route 2....

 exposed workers and community residents to danger by mining contaminated vermiculite. In 1999 the EPA began cleanup efforts and now the area is a Superfund
Superfund
Superfund is the common name for the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 , a United States federal law designed to clean up sites contaminated with hazardous substances...

 cleanup area. The EPA has determined that harmful asbestos is released from the mine as well as through other activities that disturb soil in the area.

Asbestos and talc


Talc
Talc
Talc is a mineral composed of hydrated magnesium silicate with the chemical formula H2Mg34 or Mg3Si4O102. In loose form, it is the widely-used substance known as talcum powder. It occurs as foliated to fibrous masses, its crystals being so rare as to be almost unknown...

 is sometimes contaminated with asbestos. In 2000, tests in a certified asbestos-testing laboratory found the tremolite form of amphibole asbestos in three out of eight bigger brands of children's crayon
Crayon
A crayon is a stick of colored wax, charcoal, chalk, or other materials used for writing, coloring, drawing, and other methods of illustration. A crayon made of oiled chalk is called an oil pastel; when made of pigment with a dry binder, it is simply a pastel; both are popular media for color...

s that are made partly from talc: Crayola
Crayola
Crayola is a brand of artists' supplies manufactured by Crayola LLC, which was founded in 1885 as Binney & Smith. It is best known for its crayons...

, Prang, and RoseArt. In Crayola crayons, the tests found asbestos levels from 0.05% in Carnation Pink to 2.86% in Orchid; in Prang crayons, the range was from 0.3% in Periwinkle to 0.54% in Yellow; in Rose Art crayons, it was from 0.03% in Brown to 1.20% in Orange. Overall, 32 different types of crayons from these brands contained more than trace amounts of asbestos, and eight others contained trace amounts. The Art and Creative Materials Institute, a trade association
Trade association
A trade association, also known as an industry trade group, business association or sector association, is an organization founded and funded by businesses that operate in a specific industry...

 which tests the safety of crayons on behalf of the makers, initially insisted the test results must be incorrect, although they later said they do not test for asbestos. In May 2000, Crayola said tests by a materials analyst, Richard Lee, whose testimony has been accepted in lawsuits over 250 times on behalf of the asbestos industry, showed two of its crayons were negative for asbestos. In June 2000, Binney & Smith, the maker of Crayola, and the other makers agreed to stop using talc in their products, and changed their product formulations in the United States. The mining company, R T Vanderbilt Co of Gouverneur, New York
Gouverneur (town), New York
Gouverneur is a town in St. Lawrence County, New York, United States. The population was 7,418 at the 2000 census. The town is named after statesman and landowner Gouverneur Morris....

, which supplied the talc to the crayon makers, insists there is no asbestos in its talc "to the best of our knowledge and belief", but a news article claimed that the United States Mine Safety and Health Administration (MSHA) did find asbestos in four talc samples that it tested in 2000. At the time, however, the Assistant Secretary for Mine Safety and Health informed the news reporter that his article was in error and that the reporter had misquoted him stating that “In fact, the abbreviation ND (non detect) in the laboratory report – indicates no asbestos fibers actually were found in the samples.” Further supporting the claim of Vanderbilt that asbestos is not found in this industrial grade talc (composed of a very complex mineral mixture) is a decades old record of analytical work that does not find asbestos in this talc by mineral scientists in academia, government and contract laboratories.

Human, animal and cell health studies conducted on Vanderbilt’s controversial talc also lend no support for the presence of asbestos in this talc. Several non fully peer-reviewed health reports concerning Vanderbilt talc do exist and suggest a "same as" asbestos risk, some of which were referenced in the previously cited news articles.

Asbestos construction in developed countries


The use of asbestos in new construction projects has been banned for health and safety reasons in many developed countries or regions, including the European Union
European Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...

, Australia, Hong Kong
Hong Kong
Hong Kong is one of two Special Administrative Regions of the People's Republic of China , the other being Macau. A city-state situated on China's south coast and enclosed by the Pearl River Delta and South China Sea, it is renowned for its expansive skyline and deep natural harbour...

, Japan, and New Zealand. A notable exception is the United States, where asbestos continues to be used in construction such as cement asbestos pipes. The 5th Circuit Court prevented the EPA from banning asbestos in 1991 because although EPA research showed it would cost between $450 and 800 million and save around 200 lives in a 13-year length, the EPA did not provide adequate evidence for the safety of alternative products.
Until the mid-1980s, small amounts of white asbestos were used in the manufacture of Artex
Artex
Artex is a surface coating used for interior decorating, most often found on ceilings, which allows the decorator to add a texture to it. The name Artex is a trademark of Artex Ltd., a company based in the UK. The name is a genericised trademark often used to refer to similar products from other...

, a decorative stipple finish, however, some of the lesser-known suppliers of Artex were still adding white asbestos until 1999. Removing or disturbing Artex is not recommended, as it may contain white asbestos.

Prior to the ban, asbestos was widely used in the construction industry in thousands of materials, some are judged to be more dangerous than others due to the amount of asbestos and a materials friable nature. Sprayed coatings, pipe insulation and Asbestos Insulating Board (AIB) are thought to be the most dangerous due to their high content of asbestos and friable nature. Many older buildings built before the late 1990s contain asbestos. In the United States, there is a minimum standard for asbestos surveys as described by ASTM Standard E 2356-04. The U.S. Environmental Protection Agency includes some but not all asbestos-contaminated facilities on the Superfund National Priorities list (NPL)
Superfund
Superfund is the common name for the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 , a United States federal law designed to clean up sites contaminated with hazardous substances...

. Renovation and demolition of asbestos contaminated buildings is subject to EPA NESHAP and OSHA Regulations. Asbestos is not a material covered under CERCLA's innocent purchaser defense. In the UK, the removal and disposal of asbestos and of substances containing it are covered by the Control of Asbestos Regulations 2006

In older buildings (e.g. those built prior to 1999 in the UK, before white asbestos was finally banned), asbestos may still be present in some areas e.g. old bath panels, concrete water tanks and many other places. Being aware of asbestos locations reduces the risk of disturbing asbestos. See the asbestos image gallery (external link) to see some common asbestos locations.

Removal of asbestos building components can also remove the fire protection they provide, therefore fire protection substitutes are required for proper fire protection that the asbestos originally provided.

Asbestos construction in developing countries


Some developing countries, such as India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

 and China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

, and also Russia, have continued widespread use of asbestos. The most common is corrugated asbestos-cement sheets or "A/C Sheets" for roofing and for side walls. Millions of homes, factories, schools or sheds and shelters continue to use asbestos. Cutting these sheets to size and drilling holes to receive 'J' bolts to help secure the sheets to roof framing is done on-site. There has been no significant change in production and use of A/C Sheets in developing countries
Developing country
A developing country, also known as a less-developed country, is a nation with a low level of material well-being. Since no single definition of the term developing country is recognized internationally, the levels of development may vary widely within so-called developing countries...

 following the widespread restrictions in developed nations.

Asbestos and 9/11


More than 1,000 tons of asbestos are thought to have been released into the air during the destruction of the Twin Towers in New York
New York
New York is a state in the Northeastern region of the United States. It is the nation's third most populous state. New York is bordered by New Jersey and Pennsylvania to the south, and by Connecticut, Massachusetts and Vermont to the east...

 on 9/11. Inhalation of a mixture of asbestos and other toxicants is thought to be linked to the unusually high death rate of emergency service workers from cancer since the disaster. Many thousands more are now thought to be at risk of developing cancer due to this exposure with those who have died so far being only the 'tip of the iceberg'. Some commentators have criticised authorities for using asbestos in the Towers' construction (see 'Other criticism' below).

Litigation


Asbestos litigation is the longest, most expensive mass tort
Tort
A tort, in common law jurisdictions, is a wrong that involves a breach of a civil duty owed to someone else. It is differentiated from a crime, which involves a breach of a duty owed to society in general...

 in U.S. history
History of the United States
The history of the United States traditionally starts with the Declaration of Independence in the year 1776, although its territory was inhabited by Native Americans since prehistoric times and then by European colonists who followed the voyages of Christopher Columbus starting in 1492. The...

, involving more than 8,400 defendants and 730,000 claimants as of 2002 according to the RAND Corporation, and at least one defendant reported claim counts in excess of 800,000 in 2006.

Current trends indicate that the worldwide rate at which people are diagnosed with asbestos-related diseases will likely increase through the next decade. Analysts have estimated that the total costs of asbestos litigation in the USA alone is over $250 billion.

The federal legal system in the United States has dealt with numerous counts of asbestos related suits, which often included multiple plaintiffs with similar symptoms. In 1999 there were 200,000 related cases pending in the federal court system of the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

. Further, it is estimated that within the next 40 years, the number of cases may increase to 700,000. These numbers help explain how there are thousands of current pending cases.

Litigation of asbestos materials has been slow. Companies sometimes counter saying that health issues do not currently appear in their worker or workers, or sometimes are settled out of court. The Research and Development (RAND) think tank has appropriated certain legal information which is readily available for proclaimed victims of natural resource accidents. This information has helped many workers, regardless of health condition, earn compensation through companies. RAND
RAND
RAND Corporation is a nonprofit global policy think tank first formed to offer research and analysis to the United States armed forces by Douglas Aircraft Company. It is currently financed by the U.S. government and private endowment, corporations including the healthcare industry, universities...

, along with the Institute for Civil Justice (ICJ) have been proponents of the organization of past cases in order to determine one aspect of fair compensation for workers.

1999 saw the introduction of the Fairness in Asbestos Compensation Act. Ultimately many asbestos companies were forced to file for bankruptcy. While companies filed for bankruptcy, this limited payouts to those who were actually affected by the material. Christopher Edley said what the 1999 Act ultimately did was "limit punitive damages that seek retribution for the decisions of long-dead executives for conduct that took place decades ago (Professor Christopher Edley, Jr.
Christopher Edley, Jr.
Christopher Fairchild Edley, Jr. is Dean of the University of California, Berkeley School of Law . After receiving his undergraduate degree from Swarthmore College, he attended Harvard Law School, where he later served as a professor. He is married to Maria Echaveste, former deputy chief of staff...

).”

Litigation exists outside the United States in England, Scotland, Ireland, the Netherlands, France, Australia, and Japan among other nations. See the companion article
Asbestos and the law
This article concerns asbestos-related legal and regulatory issues. Litigation related to asbestos injuries and property damages has been claimed to be the longest-running mass tort in U.S. history...

 for further information.

The volume of the asbestos liability has concerned manufacturers and insurers and reinsurers. The amounts and method of allocating compensation have been the source of many court cases, and government attempts at resolution of existing and future cases.

Canada-EU dispute


Natural Resources Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

 states chrysotile
Chrysotile
Chrysotile or white asbestos is the most commonly encountered form of asbestos, accounting for approximately 95% of the asbestos in place in the United States and a similar proportion in other countries. It is a soft, fibrous silicate mineral in the serpentine group of phyllosilicates; as such, it...

, one of the fibres that make up asbestos, is not as dangerous as once thought. According to their fact sheet, "current knowledge and modern technology can successfully control the potential for health and environmental harm posed by chrysotile".

In May 1998, Canada requested consultations before the WTO and the European Commission
European Commission
The European Commission is the executive body of the European Union. The body is responsible for proposing legislation, implementing decisions, upholding the Union's treaties and the general day-to-day running of the Union....

 concerning France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

's 1996 prohibition of the importation and sale of asbestos. Canada said that the French measures contravened provisions of the Agreements on Sanitary and Phytosanitary Measures and on Technical Barriers to Trade, and the GATT 1994. The EC claims that substitute materials have been developed in place of asbestos, which are safer to human health. It stressed that the French measures were not discriminatory, and were fully justified for public health reasons. The EC claimed that in the July consultations, it had tried to convince Canada that the measures were justified, and that just as Canada broke off consultations, it was in the process of submitting substantial scientific data in favour of the asbestos ban.

The Canadian federal government has in response claimed that chrysotile is much less dangerous than other types of asbestos, and Canada does not export the other asbestos fibre. Chrysotile continues to be used in new construction across Canada, in ways that are very similar to those for which chrysotile is exported. The Chrysotile Institute, an asbestos industry funded organization, said that the use of chrysotile does not pose an environmental problem and the inherent risks in its use are limited to the workplace. The Canadian government continues to draw both domestic and international criticism for its stance on chrysotile, most recently in international meetings on the Rotterdam Convention
Rotterdam Convention
The Rotterdam Convention on the Prior Informed Consent Procedure for Certain Hazardous Chemicals and Pesticides in International Trade, more commonly known simply as the ', is a multilateral treaty to promote shared responsibilities in relation to importation of hazardous chemicals...

 hearings regarding chrysotile.

The CFMEU
Construction, Forestry, Mining and Energy Union
The Construction, Forestry, Mining and Energy Union is Australia's main trade union in construction, forestry and furnishing products, mining and energy production....

 pointed out that most exports go to developing countries. Canada has pressured countries, including Chile
Chile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...

, and other UN member states to avoid chrysotile bans.

Other criticism


Asbestos regulation critics include the asbestos industry and Fox News columnist Steven Milloy
Steven Milloy
Steven J. Milloy is a commentator for Fox News and runs the Web site junkscience.com, which is dedicated to "debunking" what Milloy labels "faulty scientific data and analysis." On Fox News Channel he is billed as a "Junk Science commentator." He describes himself as a libertarian.Among the topics...

. Critics sometimes argue that increased government regulation does more harm than good and that replacements to asbestos are inferior. An example is the suggestion by Dixy Lee Ray
Dixy Lee Ray
Dixy Lee Ray was the 17th Governor of the U.S. State of Washington. She was Washington's first female governor.-Early years:...

 and others that the shuttle Challenger disintegrated because the maker of O-ring
O-ring
An O-ring, also known as a packing, or a toric joint, is a mechanical gasket in the shape of a torus; it is a loop of elastomer with a disc-shaped cross-section, designed to be seated in a groove and compressed during assembly between two or more parts, creating a seal at the interface.The O-ring...

 putty was pressured by the EPA into ceasing production of asbestos-laden putty. However, the putty used in Challengers final flight did contain asbestos, and failures in the putty were not responsible for the failure of the O-ring that led to loss of the shuttle.

Asbestos was used in the first forty floors of the World Trade Center
World Trade Center
The original World Trade Center was a complex with seven buildings featuring landmark twin towers in Lower Manhattan, New York City, United States. The complex opened on April 4, 1973, and was destroyed in 2001 during the September 11 attacks. The site is currently being rebuilt with five new...

 north tower causing an airborne contamination among lower Manhattan after the towers collapsed in the attacks on September 11th, 2001
September 11, 2001 attacks
The September 11 attacks The September 11 attacks The September 11 attacks (also referred to as September 11, September 11th or 9/119/11 is pronounced "nine eleven". The slash is not part of the pronunciation...

. Steven Milloy
Steven Milloy
Steven J. Milloy is a commentator for Fox News and runs the Web site junkscience.com, which is dedicated to "debunking" what Milloy labels "faulty scientific data and analysis." On Fox News Channel he is billed as a "Junk Science commentator." He describes himself as a libertarian.Among the topics...

 suggests that the World Trade Center
World Trade Center
The original World Trade Center was a complex with seven buildings featuring landmark twin towers in Lower Manhattan, New York City, United States. The complex opened on April 4, 1973, and was destroyed in 2001 during the September 11 attacks. The site is currently being rebuilt with five new...

 towers could still be standing or at least would have stood longer had a 1971 ban not stopped the completion of the asbestos coating above the 64th floor. This was not considered in the National Institute of Standards and Technology
National Institute of Standards and Technology
The National Institute of Standards and Technology , known between 1901 and 1988 as the National Bureau of Standards , is a measurement standards laboratory, otherwise known as a National Metrological Institute , which is a non-regulatory agency of the United States Department of Commerce...

's report on the towers' collapse. All fireproofing
Fireproofing
Fireproofing, a passive fire protection measure, refers to the act of making materials or structures more resistant to fire, or to those materials themselves, or the act of applying such materials. Applying a certification listed fireproofing system to certain structures allows these to have a...

 materials, regardless of what they are made of, are required to obtain a fire-resistance rating
Fire-resistance rating
A fire-resistance rating typically means the duration for which a passive fire protection system can withstand a standard fire resistance test. This can be quantified simply as a measure of time, or it may entail a host of other criteria, involving other evidence of functionality or fitness for...

 prior to installation. All fiber-based lightweight commercial spray fireproofing materials are vulnerable to kinetic energy
Kinetic energy
The kinetic energy of an object is the energy which it possesses due to its motion.It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes...

 impacts that are outside of the fire test
Fire test
A fire test is a means of determining whether or not fire protection products meet minimum performance criteria as set out in a building code or other applicable legislation. Successful tests in laboratories holding national accreditation for testing and certification result in the issuance of a...

ing upon which their ratings are based, including asbestos-based materials, and may have been removed in large areas by the impact of the planes.

Substitutes for asbestos in construction


Fiberglass
Fiberglass
Glass fiber is a material consisting of numerous extremely fine fibers of glass.Glassmakers throughout history have experimented with glass fibers, but mass manufacture of glass fiber was only made possible with the invention of finer machine tooling...

 insulation
Building insulation
building insulation refers broadly to any object in a building used as insulation for any purpose. While the majority of insulation in buildings is for thermal purposes, the term also applies to acoustic insulation, fire insulation, and impact insulation...

 was invented in 1938 and is now the most commonly used type of insulation material
Building insulation materials
Building insulation materials are thermal insulation used in the construction or retrofit of buildings.The materials are used to reduce heat transfer by conduction, radiation or convection and are employed in varying combinations to achieve the desired outcome .-Categories:Insulation may be...

. The safety of this material is also being called into question, as research shows that the composition of this material (asbestos and fiberglass are both silicate fibers) causes similar toxicity as asbestos.

In 1978, a highly texturized fiberglass
Fiberglass
Glass fiber is a material consisting of numerous extremely fine fibers of glass.Glassmakers throughout history have experimented with glass fibers, but mass manufacture of glass fiber was only made possible with the invention of finer machine tooling...

 fabric was invented by Bal Dixit
Bal Dixit
Bal Dixit is the chairman of Newtex Industries. He founded the company in 1978 after being one of the first researchers to formulate a viable alternative to asbestos in fire safety gear. In 1977, he started work on developing a product he would later call Zetex in response to the impending asbestos...

, called Zetex
Zetex (fabric)
Zetex fabrics were invented by Bal Dixit in 1978. This highly texturized fiberglass fabric exhibits many of the same properties as asbestos, such as resistance to heat, corrosion and rot resistance, outstanding electrical properties, ability to withstand molten metal, and thermal insulation....

. This fabric is lighter than asbestos, but offers the same bulk, thickness, hand, feel, and abrasion resistance as asbestos. The fiberglass was texturized to eliminate some of the problems that arise with fiberglass, such as poor abrasion resistance and poor seam strength

In Europe stone-
Mineral wool
Mineral wool, mineral fibers or man-made mineral fibers are fibers made from natural or synthetic minerals or metal oxides. The latter term is generally used to refer solely to synthetic materials including fiberglass, ceramic fibers and stone wool...

 and glasswool
Glass wool
Glass wool or fiberglass insulation is an insulating material made from fiberglass, arranged into a texture similar to wool. Glass wool is produced in rolls or in slabs, with different thermal and mechanical properties....

 are the main insulators in houses.

Many companies that produced asbestos-cement products that were reinforced with asbestos fibers have developed products incorporating organic fibers. One such product was known as Eternit
Eternit
Eternit is the registered trademark for fibre cement. This has caused fibre cement to be known under the "Eternit" brand. Though, this is not to be confused, "Eternit" is only a trademark for fibre cement....

 and another "Everite" now use "Nutec" fibers which consist of organic fibers, portland cement
Portland cement
Portland cement is the most common type of cement in general use around the world because it is a basic ingredient of concrete, mortar, stucco and most non-specialty grout...

 and silica. Cement-bonded wood fiber
Cement-bonded wood fiber
Cement-bonded wood fiber is a composite material manufactured throughout the world. It is made from wood , chipped into a specially graded aggregate that is then mineralized and combined with portland cement.- Uses :...

 is another substitute. Stone fibers are used in gaskets and friction materials.

Another potential fiber is polybenzimidazole or PBI fiber. Polybenzimidazole fiber
Polybenzimidazole fiber
Polybenzimidazole fiber is a synthetic fiber with a very high melting point that also does not readily ignite, because of its exceptional thermal and chemical stability. The U.S...

 is a synthetic fiber
Synthetic fiber
Synthetic fibers are the result of extensive research by scientists to improve on naturally occurring animal and plant fibers. In general, synthetic fibers are created by forcing, usually through extrusion, fiber forming materials through holes into the air, forming a thread...

 with high melting point
Melting point
The melting point of a solid is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depends on pressure and is usually specified at standard atmospheric pressure...

 of 760 °C that also does not ignite. Because of its exceptional thermal and chemical stability, it is often used by fire departments
Fire station
A fire station is a structure or other area set aside for storage of firefighting apparatus , personal protective equipment, fire hose, fire extinguishers, and other fire extinguishing equipment...

 and space agencies.

Asbestos alternatives for industrial use include sleeves, rope, tape, fabric, textiles and insulation batt materials made from fiberglass and silica.

Recycling and disposal


In most developed countries, asbestos is typically disposed of as hazardous waste
Hazardous waste
A hazardous waste is waste that poses substantial or potential threats to public health or the environment. According to the U.S. environmental laws hazardous wastes fall into two major categories: characteristic wastes and listed wastes.Characteristic hazardous wastes are materials that are known...

 in landfill sites.

Asbestos can also be recycled by transforming it into harmless silicate glass. A process of thermal decomposition at 1000–1250 °C produces a mixture of non-hazardous silicate
Silicate
A silicate is a compound containing a silicon bearing anion. The great majority of silicates are oxides, but hexafluorosilicate and other anions are also included. This article focuses mainly on the Si-O anions. Silicates comprise the majority of the earth's crust, as well as the other...

 phases, and at temperatures above 1250 °C it produces silicate glass. Microwave thermal treatment can be used in an industrial manufacturing process to transform asbestos and asbestos-containing waste into porcelain stoneware tiles, porous single-fired wall tiles, and ceramic bricks.

Other asbestos-related topics


  • Adequately wet
    Adequately wet
    The phrase "adequately wet" is an environmental term referring to the handling of asbestos containing work, such as the demolition of older houses containing carcinogenic asbestos tiles or roof materials. Since there is no minimum threshold for a safe level of outdoor asbestos particle...

  • Ambler, Pennsylvania
  • Artex
    Artex
    Artex is a surface coating used for interior decorating, most often found on ceilings, which allows the decorator to add a texture to it. The name Artex is a trademark of Artex Ltd., a company based in the UK. The name is a genericised trademark often used to refer to similar products from other...

  • Asbestos abatement
    Asbestos abatement
    Many buildings contain asbestos, which was used in spray-applied flame retardant, thermal system insulation, and in a variety of other materials. Asbestos was sometimes "flocked" above false ceilings, inside technical ducts, and in many other small spaces where firefighters would have difficulty...

  • Asbestos and the law
    Asbestos and the law
    This article concerns asbestos-related legal and regulatory issues. Litigation related to asbestos injuries and property damages has been claimed to be the longest-running mass tort in U.S. history...

  • Asbestos Disease Awareness Organization
    Asbestos Disease Awareness Organization
    Asbestos Disease Awareness Organization is an independent organization headquartered in Redondo Beach, California. Founded by Linda Reinstein and Doug Larkin on April 1, 2004, ADAO is the largest victims’ organization dedicated to preventing asbestos-related diseases through education and...

  • Asbestos fibers
    Asbestos fibers
    Asbestos fibers are released from asbestos containing materials . Friable asbestos containing materials release fibers more readily than encapsulated asbestos containing materials.- Determining airborne asbestos fiber levels :...

  • Asbestos-ceramic
    Asbestos-Ceramic
    Asbestos-ceramic refers to types of pottery manufactured with asbestos and clay with adiabatic behaviour in Finland, Karelia and Northern-Scandinavia...

  • Asbestosis
    Asbestosis
    Asbestosis is a chronic inflammatory and fibrotic medical condition affecting the parenchymal tissue of the lungs caused by the inhalation and retention of asbestos fibers...

  • Asbestos, Quebec
    Asbestos, Quebec
    -Communities:*Asbestos*Trois-Lacs-External links:***...

  • Avondale Landfill
    Avondale Landfill
    The Avondale Landfill is a major Scottish landfill located in Polmont, off junction 4 of the M9 motorway. Avondale takes large volumes of waste from the Forth Valley and some from West Lothian. Avondale has the ability to accept Non-Hazardous, Stable Non-Reactive Hazardous waste including...

     (in Polmont
    Polmont
    Polmont is a village in the Falkirk council area of Central Scotland. It lies towards the east of the town of Falkirk, north of the Union Canal, which runs adjacent to the village....

     in Scotland
    Scotland
    Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...

    )
  • Brominated flame-retardant
    Brominated flame-retardant
    Brominated flame retardants are organobromide compounds that have an inhibitory effect on the ignition of combustible organic materials. Of the commercialized chemical flame retardants, the brominated variety are most widely used. They are very effective in plastics and textile applications, e.g....

  • Cemesto
    Cemesto
    Cemesto is a sturdy, light-weight, waterproof and fire-resistant composite building material made from a core of sugar cane fiber insulating board surfaced on both sides with asbestos and cement. Its name is a portmanteau word combining "cem" from "cement" and "esto" from "asbestos."Cemesto was...

  • Eternit
    Eternit
    Eternit is the registered trademark for fibre cement. This has caused fibre cement to be known under the "Eternit" brand. Though, this is not to be confused, "Eternit" is only a trademark for fibre cement....

  • Fibro
    Fibro
    Fibro, the shortened form of "Fibrous Cement" - or "Fibrous Asbestos Cement", FAC, is a building material made of compressed fibres cemented into rigid sheets....

  • Fireproofing
    Fireproofing
    Fireproofing, a passive fire protection measure, refers to the act of making materials or structures more resistant to fire, or to those materials themselves, or the act of applying such materials. Applying a certification listed fireproofing system to certain structures allows these to have a...

  • Hunt v. T&N plc
    Hunt v. T&N plc
    Hunt v. T&N plc, [1993] 4 S.C.R. 289 is a landmark decision of the Supreme Court of Canada on conflict of laws. The Court ruled that the Quebec law prohibiting the removal of company documents from the province was constitutionally inapplicable to a British Columbia court order. The decision was...

  • Institute of Occupational Medicine
    Institute of Occupational Medicine
    The Institute of Occupational Medicine was founded in 1969 by the National Coal Board as an independent charity. The IOM is a major independent centre of scientific excellence in the fields of occupational health and environmental health, occupational hygiene and occupational safety...

  • James Hardie
    James Hardie
    James Hardie Industries Ltd. is an industrial building materials company headquartered in Ireland and listed on the Australian Securities Exchange which specialises in fibre cement products. James Hardie manufactures and develops technologies, materials and processes for the production of building...

  • Medical geology
    Medical geology
    Medical geology is an emerging interdisciplinary scientific field consisting of those aspects of geology as they affect human, animal and plant health.Examples include:*Lead and other heavy metal exposure resulting from dust and other particulates...

  • Mesothelioma
    Mesothelioma
    Mesothelioma, more precisely malignant mesothelioma, is a rare form of cancer that develops from the protective lining that covers many of the body's internal organs, the mesothelium...

  • Rotterdam Convention
    Rotterdam Convention
    The Rotterdam Convention on the Prior Informed Consent Procedure for Certain Hazardous Chemicals and Pesticides in International Trade, more commonly known simply as the ', is a multilateral treaty to promote shared responsibilities in relation to importation of hazardous chemicals...

  • Transite
    Transite
    Transite originated as trade name that The Johns-Manville Corporation created for a line of asbestos-cement products, including boards and pipes...

  • Turner & Newall
    Turner & Newall
    Turner & Newall was a leading manufacturing business based in Manchester, United Kingdom. At its peak, it was a constituent of the FT30 index of leading companies on the London Stock Exchange.-1871-1920:...

  • Wittenoom, former asbestos mining town
    Wittenoom, Western Australia
    Wittenoom is a ghost town located 1,106 kilometres north-northeast of Perth in the Hamersley Range in the Pilbara region of Western Australia. It is the site of Australia's greatest industrial disaster....


Further reading

  • George B. Guthrie and Brooke T. Mossman, editors, Health Effects of Mineral Dusts, Mineralogical Society of America
    Mineralogical Society of America
    The Mineralogical Society of America is a scientific membership organization. MSA was founded in 1919 for the advancement of mineralogy, crystallography, geochemistry, and petrology, and promotion of their uses in other sciences, industry, and the arts...

     Reviews in Mineralogy v. 28, 584 pages (1993) ISBN 0-939950-33-2.

External links


Regulatory and government links

Mineral and mining links

Health and the environment