October 12, 2011

The history of asbestos

The history of asbestos as we know it dates back 2000 years. It was the Greeks who named this mineral asbestos, meaning inextinguishable. The ancient Greeks observed the harmful biological effects but continued to use the mineral said to have magical properties. Pliny (Roman naturalist) and Strabo (Greek geographer) noted an appearance of "sickness of the lungs" in slaves who wove asbestos into cloth. The Greeks also used asbestos for the wicks of the eternal flames of the vestal virgins, as the funeral dress worn by kings and for napkins. They were so impressed with the magical properties of the mineral that they were willing to overlook its harmful symptoms for humans. They went as far as calling asbestos "amiantus", meaning "unpolluted.

During the middle ages, it was believed that the Frankish king, Charlemagne had asbestos tablecloths. Asbestos products were used in the 1700 hundreds but did not really become popular until the late 1800's. The industrial Revolution demanded new uses for the mineral. It was used as insulation for steam pipes, turbines, boilers, kilns, ovens, and other high-temperature products.

The history of asbestos use continued into the twentieth century and researchers began to investigate the harmful toxic affects. It was first noticed in 1917 and 1918 that a great number of young people in asbestos mining towns prematurely died. Researchers in England carried out clinical studies on asbestos workers in 1924, after the recorded death of a young woman who had been diagnosed with the new disease they called asbestosis. Twenty-five percent of the test subjects showed evidence of asbestos-related lung disease. Legislation was enacted in 1931, to increase ventilation and to recognize asbestosis a work-related disease.

The 1930's brought in with it, the surge of major medical research articles, warning about the asbestos connection with lung cancer partially due to a new disease, silicosis, caused by in haling silica dust particles. Much of this research continued to be ignored. Large Asbestos companies continued to use asbestos in manufacturing and construction, despite that fact that safer alternatives such as fiberglass insulation were created to replace it. These companies hid their lung cancer findings to avoid the million dollar lawsuits brought upon them by asbestos cancer victims. The history of asbestos use and company profiteering has no doubt exploited asbestos workers then and now. Today, victims exposed to asbestos are faced with mesothelioma cancer and certain death.

What is Asbestos?

Asbestos is a naturally occurring mineral fiber mined from the earth. It is strong, flexible, and resistant to heat, chemicals and electrical conditions.

Forms of Asbestos 

The three most common forms of asbestos are divided into two groups. The serpentine group includes white (chrysotile) asbestos. The amphibole group includes brown (amosite) and blue (crocidolite) asbestos.

Asbestos Properties

Asbestos has many properties that once made it attractive to industry. It is stable when heated, it provides strength under tension, it is resistant to chemicals and does not absorb water (depending on type of asbestos). Asbestos is suitable for weaving and can be used to reinforce materials such as concrete. And lastly, it is a good resistance to electricity.

Asbestos Categories

'Bonded' is used to refer to asbestos being so firmly embedded in a material that these materials are unlikely to release measurable levels of asbestos fiber into the air if they are left undisturbed. Therefore, they generally pose a lower risk to health.

Bonded asbestos-containing materials include asbestos cement products (flat and corrugated sheeting used in walls, ceilings and roofs, molded items such as down pipes), vinyl floor coverings. 'Friable' is used to refer to asbestos-containing materials that can be easily reduced to powder by hand, when dry. These materials are more likely to release measurable levels of asbestos into the air when disturbed, and generally pose a greater risk to health. Friable asbestos-containing materials include sprayed asbestos fire retardants

Asbestos Industry

In the past, the asbestos industry used around 3000 products manufactured worldwide, most commonly in the construction, car manufacturing and textile industries. It was generally manufactured in the following forms: fibrous (limpet asbestos), woven (cloth, tape or sleeving), wound (rope) or mixed with a binder, such as calcium silicate (to make asbestos cement or vinyl floor products containing asbestos).

Because of its strength and its ability to resist heat and chemicals, asbestos was used in a range of insulation materials.

Older commercial industrial buildings and private dwellings may contain a variety of asbestos products, such as asbestos-cement sheeting in walls and ceilings, or roof cladding made from corrugated asbestos-cement. Asbestos may be found in structures built as late as the mid- to late 1980s.

Asbestos Related Occupations

Asbestos has been used in association with a number of occupations such as the US military and armed forces, particularly the Navy. Massive amounts of asbestos were used in shipbuilding and commercial construction prior to the mid-1970's.

Other workers in occupations which have been associated with asbestos use are:
Insulators, Pipe Fitters, Plumbers, Electricians, Painters, Crane Operators, Floor Coverers, Pot Tenders, Welders, Paper Mill Workers, Custodians, Steam Fitters, Tile Setters, Aerospace Workers, Mechanics, Building Engineers, Demolition Crews, Former US Navy Personnel, Packing/Gasket Manufacturing Workers, Protective Clothing Manufacturing, Rubber Workers, Warehouse Workers, Home Improvement, Hospitals, Schools, Loading Docks, Glass Factory Workers, Building Inspectors, Bulldozer Operators, Manufacturing Workers, Excavating machine operators, Heavy Equipment Mechanics, Job and Die setters, Contractors, Building Managers, Mixing Operatives, Laborers, Sawyers, Teachers, Tinsmiths, Weavers, Excavators, Technicians

Risks of Asbestos Exposure

Humans come into contact with asbestos when they swallow or inhale the fibers. These particles can then become embedded in the tissues of the respiratory or digestive systems.

Three Main Diseases Caused by Asbestos Exposure

Asbestosis

Asbestosis causes widespread scar tissue between the alveoli, or spread over the lung. It is difficult to distinguish from other causes of interstitial fibrosis. Only confirmation of exposure to asbestos or detection of unusually high numbers of asbestos fibers in the lung is considered conclusive evidence of this disease.