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Asbestos This page is about the group of minerals. For the locations in Quebec, see Asbestos and Asbestos Regional County Municipality "quicklime" from Greek ἄσβεστος: a-, "not"; sbestos, "extinguishable") describes any of a group of fibrous metamorphic minerals of the hydrous magnesium silicate variety. The name is derived for its historical use in lamp wicks; the resistance of asbestos to fire has long been exploited for a variety of purposes. It was used in fabrics such as Egyptian burial cloths and Charlemagne's tablecloth, which, according to legend, he threw in a fire to clean. Asbestos occurs naturally in many forms (see below); it is mined from metamorphic deposits.

When asbestos is used for its resistance to fire or heat, the fibers are typically mixed with cement or woven into fabric or mats. It is used in brake shoes and gaskets for its heat resistance, and in the past was used on electric oven and hotplate wiring for its electrical insulation at elevated temperature, and in buildings for its flame-retardant and insulating properties, its tensile strength, flexibility, and resistance to chemicals. However, the inhalation of some kinds of asbestos fibers causes various serious illnesses, including cancer, and thus most uses of asbestos are banned in many countries. Fiberglass has been found to be a suitable substitute for thermal insulation and woven ceramic fiber performs as well or better as an insulator of high-temperature electrical conductors.

Most respirable asbestos fibers are invisible to the unaided human eye because their size is about 3.0-20.0 µm in length and can be as thin as 0.01 µm. Human hair ranges in size from 17 to 181 µm.[1] Fibers ultimately form because when these minerals originally cooled and crystallized, they formed by the polymeric molecules lining up parallel with each other and forming oriented crystal lattices. These crystals thus have three cleavage planes as other minerals and gemstones have. But in their case, there are two cleavage planes that are much weaker than the third direction. Thus 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 over and over until they have been broken down to their smallest unit dimensions. For this reason, one larger asbestos fiber can ultimately become the source of hundreds of much thinner and smaller fibers in a normal environment over the course of time. As they get smaller and lighter, they become more mobile and more easily entrained (wafted) into the air, where human respiratory exposures typically result.

Confusingly, the Modern Greek word i, CAS No. 12001-29-5, is obtained from Canadian serpentine rocks. It is less friable (and therefore less likely to be inhaled) than the other types and is the type most often used industrially. Chrysotile should not be confused with chrysolite, a synonym of olivine. There is some evidence that this form of asbestos is not actually harmful when inhaled. However it should be noted that there is also evidence that this type of asbestos is harmful, although not perhaps as harmful as other forms (refer to UK Health , is an amphibole from Africa, named as an acronym from Asbestos Mines of South Africa. One formula given for Amosite is Fesub, CAS No. 12001-28-4, is an amphibole from Africa and Australia. It is the fibrous form of riebeckite. Blue asbestos is commonly thought of as the most dangerous type of asbestos (see above and below). One formula given for Crocidolite is Nasub

Notes: Serpentine rocks are those with curled fibres. Amphiboles have straight, needle-like fibres.

The amphiboles, in their fibrous form, are friable and therefore the most carcinogenic, although they also exist in safer non-fibrous forms. Asbestos with particularly fine fibers is also referred to as "amianthus".

Other asbestos minerals, such as tremolite, CAS No. 77536-68-6, Casub; are less-used industrially but can still be found in a variety of construction materials and insulations and occur in a few consumer products, such as talcum powders and vermiculite. In the United States, the Environmental Protection Agency (EPA) has banned all construction-related products that have asbestos content of 1% or greater. It has also banned asbestos in all other friable (easily crushed by finger pressure) products.

Chrysotile is the form of asbestos from the serpentine group that has been used commercially.

In the United States, chrysotile has been the most commonly used type of asbestos. Chrysotile is often present in a wide variety of materials, including but not limited to:

Amosite and crocidolite were used in many products until the early 1980s. The use of all types of asbestos in the amphibole group was banned in the mid-1980s. These products were mainly:

Strong concerns about the health hazards associated with asbestos had been described many times over the years. As early as 1898 the Chief Inspector of Factories of the United Kingdom reported to Parliament in his Annual Report about the "evil effects of asbestos dust". He reported the "sharp, glass like nature of the particles" when allowed to remain in the air in any quantity, "have been found to be injurious, as might have been expected" (Report of the Select Committee 1994). In 1906 a British Parliamentary Commission confirmed the first cases of asbestos deaths in factories in Britain and recommended better ventilation and other safety measures. In 1918 a US insurance company produced a study showing premature deaths in the asbestos industry in the United States and in 1926 the Massachusetts Industrial Accidents Board processed the first successful compensation claim by a sick asbestos worker. Many American injuries from asbestos exposure came from shipbuilders working during World War II.[2]

The fine asbestos fibres are easily inhaled, and can cause a number of respiratory complaints, including a potentially serious lung fibrosis called i. Exposure to asbestos has also been determined to cause a very serious form of cancer, mesothelioma, that occurs in the chest and abdominal cavities. This aggressive disease is improperly referred to as a lung cancer, as the malignant cells are derived from the mesothelium, a tissue found on the inner walls of the chest and abdominal cavities and on the outer surface of the lungs rather than in the lung itself.

When inhaled, asbestos is carcinogenic. In the United States alone, it is estimated that ten thousand people die each year of asbestos-related diseases, such as mesothelioma, asbestosis, lung cancer, and gastrointestinal cancer. Asbestos has a synergistic effect with tobacco smoking in the causation of lung cancer.

– caused when the sharp fibres lodge in the skin and are overgrown causing benign callus-like growths. – discrete fibrous or partially calcified thickened area which can be seen on X-rays of individuals exposed to asbestos. They do not become malignant nor normally cause any lung impairment. – similar to above and can sometimes be associated with asbestosis. Usually no symptoms shown but if extensive can cause lung impairment.

In the United States, asbestos was one of the first hazardous air pollutants regulated under Section 112 of the Clean Air Act of 1970. One estimate says that, in the 20th century, more than 100 million Americans were exposed to asbestos in the workplace.[3]

Today, lawsuits claiming that asbestos caused plaintiffs' diseases form a gigantic part of the total amount of lawsuits pending in American courts, with a cost of tens of billions of dollars for expenses, settlements, and judgments to date. The original asbestos manufacturers were driven into Chapter 11 bankruptcy; plaintiffs have moved to suing corporations who had more peripheral connections to asbestos; the original plaintiffs have gone from those who had mesothelioma and other serious asbestos-related health problems to include those who merely were exposed to asbestos and wished to recover for their fear of future injury.[4] Nearly every American industry has had asbestos defendants, and over 70 corporations have filed Chapter 11 bankruptcy in the face of heavy liability claims.[5], [6] Since the late 1970s, approximately 6% of all filings in American courts each year were related to asbestos, leading to its perception as a sort of poster child of tort reform and the rampant lawsuit excesses of the United States. A RAND study found that less than half the money spent on asbestos litigation went to injured parties, as opposed to attorneys' fees and administrative costs. As of 2004, asbestos cases result in about 600 to 700 appellate opinions per year (that is, including both federal and state courts); this number does not include other cases that were not appealed, or were settled or otherwise abandoned before trial. Estimates of total American deaths attributable to asbestos range from 200,000 to 265,000 (according to the March 1991 Report of the Judicial Conference Ad Hoc Committee on Asbestos Litigation). The number of suits has increased, although the leading epidemiological study, cited by attorneys on both sides, suggests that deaths peaked in the 1990s. However, others contend that deaths from asbestosis and mesothelioma have not yet peaked.[7]

"Asbestos litigation today is, for the most part, a massively fraudulent enterprise that can rightfully take its place among the pantheon of such great American swindles as the Yazoo land frauds, Credit Mobilier and Teapot Dome," said Lester Brickman, a professor at Cardozo Law School, in a recent speech on the phenomenon.[8] For example, Baron Budd, P.C., a renowned Dallas plaintiff's firm, is alleged to have coached clients how to provide winning testimony against asbestos defendants.[9] In recent years, there have been many scandals over asbestos litigation because of the number of cases involving plaintiffs who had suffered no injury other than asymptomatic pleural plaques. An investigation into claims filed for alleged silicosis found that 65% of the plaintiffs claiming to be suffering from silicosis had previously recovered from asbestos defendants by alleging that they had asbestosis.[10], [11] Many attorneys, including Peter Angelos, have become rich because they established lucrative relationships with unions that steered potential asbestos plaintiffs to their law firms in exchange for questionable financial relationships with union executives.[12], [13] In the mass screenings that would take place, it is alleged that asbestos-related ailments were systematically overdiagnosed.[14]

Because many companies filed for Chapter 11 bankruptcy in view of claims from plaintiffs (some of whom may have been uninjured), and because some of the earlier manufacturer bankruptcy proceedings underestimated future asbestos liability, many seriously injured workers received as little as ten cents on the dollar of the compensation due them.[15], [16]

Asbestos-related cases were a rare sight on the U.S. Supreme Court docket prior to 1980, but since then, the Court has dealt with asbestos-injury cases in 1986, 1993, 1995, 1997, 1999, and 2002. The 1997 and 1999 cases both involved giant settlement class actions that were designed to stabilize the liability of the largest defendants. Both settlements were ultimately overturned by the Court because they resolved the rights of future claimants who, because they were currently unknown, could not be given the notice that due process requires.

Texas passed a reform bill requiring neutral medical screening in asbestos claims. Georgia passed a reform bill that requires an out-of-state plaintiff to provide "prima facie evidence of physical impairment" that shows "to a reasonable degree of certainty" that exposure to asbestos was "a substantial contributing factor" to the plaintiff's injuries. Plaintiffs' attorneys in the state complain that this would foreclose "98%" of the pending claims, and that the law is unconstitutional.[17]

Congress is considering legislation, the Fairness in Asbestos Injury Resolution Act of 2005, that would establish a $140 billion trust fund to supplant litigation as a means to compensate victims of asbestos. Trial lawyers protest that the trust fund would undercompensate injured workers, while some conservatives argue that the trust fund does not do enough to prevent fraud; would override state reforms in Texas, Ohio, and Georgia; and would be too "leaky" to prevent future litigation problems.

Asbestos liability is one of the largest issues facing the global insurance industry today, with the industry contending that many are suing because they have been exposed but have not as yet contracted asbestos-related lung diseases, which have latency periods of 10-40 years, and because lawyers spend millions each year advertising to promote such lawsuits.[18], [19], [20]

In mid-2004, a huge public outcry across Australia followed revelations at a New South Wales government-sanctioned inquiry into the company James Hardie's handling of its asbestos injury liabilities.

In Brazil, prohibition of extraction and use of asbestos is currently under consideration.

In Japan too, recently there has been a spurt of lawsuits involving actual or potential damage due to the use of asbestos in schools and public places, following public outcry over asbestos-related deaths.

Many buildings contain asbestos, which was used in spray-applied flame retardant, thermal system insulation, and in a variety of other materials. Typically, asbestos was "flocked" above false ceilings, inside technical ducts, and in many other small spaces where firefighters would have difficulty gaining access. Structural components like asbestos panels were also used. In residences, it was often a component of a type of flocked acoustic ceiling called "popcorn ceiling", until its production was banned in the U.S. in 1978. However, the ban allowed installers to use up remaining stocks, so houses built as late as 1986 could still have asbestos in their acoustic ceilings. The only way to be sure is to remove a sample and have it tested by a competent laboratory.

Depending on how and where asbestos was applied, it might not pose any risk to most users of the building. If the fibers cannot dislodge themselves, they cannot be inhaled, and thus the risk is absent.

However, with certain ways of applying asbestos, particularly flocking, asbestos fibers may gradually drop off into the air. Furthermore, in all cases, asbestos poses special hazards to maintenance personnel who have to drill holes in walls for installation of cables or pipes.

Also, even if the workers are protected, such maintenance operation may release fibers into the air, which may be inhaled by other users later. As a consequence, interventions in areas where asbestos is present often have to follow stringent procedures.

The removal of asbestos from a building is quite difficult because of the above constraints. If removal is to be performed when users are still present in the building, it is usually necessary to relocate some of them temporarily. Typically, the part of the building from which asbestos is being removed has to be sealed off in order to prevent contamination of the other areas.

Even if the building is closed to normal users, it is necessary to seal it off from outside atmosphere so that no accessible air is contaminated. Accordingly, asbestos removal projects are long and costly. Examples of long asbestos removal enterprises include the Jussieu Campus (begun circa 1996 and still going on as of 2005) and the i (in 2005, projected duration was 3 years if the tower was emptied of its users, and 10 years if it was not).

An asbestos-containing building that is to be torn down may have to be sealed, and to have its asbestos safely removed first before ordinary demolition can be performed. The asbestos removal may take longer and cost more than the actual tearing-down of the building.

As with some other environmental prohibitions like DDT and CFCs, the movement to ban asbestos has many critics, some of whom claim either that the substance in question is not harmful, or that the ban does more harm than good [21].

Among the arguments around asbestos prohibition are:

The view that the shuttle Challenger exploded because the maker of O-ring putty was pressured by the EPA into ceasing production of its more temperature-resistant, asbestos-laden putty, prompting replacement with an inferior putty, which had continual problems of a sort which could have caused the O-ring leak and subsequent explosion.The "Amphibole Hypothesis" states that Chrysotile asbestos is not as harmful as asbestos from the amphibole group. Several studies have been conducted which support this conclusion. Criticisms have been raised about the methodology used in these studies. Several other studies have been conducted which contradict the "Amphibole Hypothesis" [22].Some countries, notably Canada, still use Chrysotile asbestos [23]. Canada has a significant economic interest in the mining of Chrysotile.The question of why asbestos is also banned in circumstances where inhalation is nearly impossible, such as when it's being included in sealed areas already dangerous to human beings, instead of simply when it might be used as insulation in a ventilated area, or other similar cases which actually expose it to people against their will.Critics argue that where asbestos has been banned, its roles were taken by products which are often either inferior, or far more expensive. They argue that this has a negative impact on society as a whole, which (especially if the previous arguments are true in whole or part) may be greater than the benefit of its removal.Health History Source: Article by the SafetyLine Institute - WorkSafe - Western Australian state governmentWhite Gold Pioneers: Asbestos Mining — The origins of asbestos mining, illustrated with many early photographs