Asbestos is a naturally occurring highly fibrous silicate mineral with long, thin, separable fibers that can be found in hundreds of countries on just about every continent. It is present in the air outdoors and in some drinkable water, including water from natural sources. The word Asbestos is derived from a Greek adjective meaning “inextinguishable.” The Greeks described asbestos as the miracle mineral because of its soft and pliant properties, as well as its ability to withstand heat.
There are two kinds of asbestos- that which belongs to the serpentine family and that which belongs to the amphibole family. The serpentine variety is curly whereas those belonging to amphibole family are very straight and needle like. Chrysotile asbestos of the serpentine family is the one most commonly used for industrial purposes.
Asbestos became increasingly popular among manufacturers and builders in the late 19th century because of its resistance to heat, electricity and chemical damage, its sound absorption and tensile strength. The thin fibers of asbestos can be spun and woven together, and possess valuable heat-resistant properties that make it suitable for insulation and other such products. Asbestos has been widely used in many industrial products, including cement, brake linings, roof shingles, flooring products, textiles, and insulation.
Asbestos as such is not harmful, as long as it’s intact. When disturbed it causes the fibers to float in the air where they are easily inhaled. Inhaled asbestos fibers remain in the body and cannot be expelled. Because of this, the fibers can easily penetrate body tissues and may deposit themselves in airways and lung tissue. The time lag between inhalation and any adverse health manifestations can be as long as 30 or more years.
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 while working 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, 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.
Significant exposure to any type of asbestos will increase the risk of lung cancer, mesothelioma and nonmalignant lung and pleural disorders, including asbestosis, pleural plaques, pleural thickening, and pleural effusions.
Many industrialized nations have banned asbestos including the European Union and a handful of other countries, such as Chile, Croatia, Australia, Argentina, and Saudi Arabia. Asbestos is not and has never been banned in the United States. In 1976, Congress passed a law to regulate toxic substances (known as the Toxic Substances Control Act) but a total ban was not suggested. In 1989 the United States Environmental Protection Agency (EPA) issued the Asbestos Ban and Phase Out Rule to ban asbestos. However the regulation was overturned two years later by a New Orleans Circuit Court of appeal decesion in Corrosion Proof Fittings v. EPA, 947 F.2d 1201 (5th Cir. 1991).
The Environmental Protection Agency’s asbestos regulations fall primarily under the authority of two different federal laws and their resulting implementations: - the Clean Air Act (CAA) (e.g., Asbestos National Emission Standards for Hazardous Air Pollutants, or NESHAP) rules, and - the Toxic Substances Control Act (TSCA) (e.g., Asbestos Ban and Phase out) Asbestos rules.
The US Consumer Product Safety Commission (CPSC) has also developed bans on use of asbestos in certain consumer products such as textured paint and wall patching compounds. The US Occupational Safety and Health Administration (OSHA) has set limits for acceptable levels of asbestos exposure in the workplace.
The first lawsuits against asbestos manufacturers appeared in 1929. Since then, many lawsuits have been filed against asbestos manufacturers and employers, for neglecting to implement adequate safety measures. The United States judicial system is now faced with numerous asbestos related suits. Asbestos litigation is the longest, most expensive mass tort in U.S. history, involving more than 8,400 defendants and 730,000 claimants as of 2002 according to the Research and Development think-tank (RAND). Current trends indicate that the worldwide rate at which people are diagnosed with asbestos-related diseases will likely increase through the next decade.
In most developed countries, asbestos is typically disposed of as hazardous waste. Asbestos can also be recycled by transforming it into harmless 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.