Asbestos Poisoning

Asbestos (a misapplication of Latin: asbestos "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. Asbestos 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 rocks.

When asbestos is used for its resistance to fire or heat, the fibers are often mixed with cement or woven into fabric or mats. Asbestos 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, tensile strength, flexibility, and resistance to chemicals. The inhalation of some kinds of asbestos fibers, however, causes various serious illnesses, including cancer. Thus, most uses of asbestos are banned in many countries. Fiberglass or Synthetic Mineral Fibre has been found to be a suitable substitute for thermal insulation, and woven ceramic fiber performs as well as or better than asbestos as an insulator of high-temperature electrical conductors.

Types of asbestos

• White asbestos - Chrysotile, CAS No. 12001-29-5, is obtained from 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 as 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 & Safety Commission report Asbestos: Effects on health of exposure to asbestos, 1985). One formula given for Chrysotile is Mg₃(Si₂O₅)(OH)₄.

• Brown asbestos - Amosite, CAS No. 12172-73-5, also known as Grunerite, is an amphibole from Africa, named as an acronym from Asbestos Mines of South Africa. One formula given for Amosite is Fe₇Si₈O₂₂(OH)₂.

• Blue asbestos - Riebeckite, CAS No. 12001-28-4, also known as Crocidolite, 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 Na₂Fe²⁺₃Fe³⁺₂Si₈O₂₂(OH)₂.

Notes: Serpentine rocks are those with curled fibers. Amphiboles have straight, needle-like fibers. e 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, Ca₂Mg₅Si₈O₂₂(OH)₂; actinolite (or smaragdite), CAS No. 77536-66-4, Ca₂(Mg, Fe)₅Si₈O₂₂(OH)₂; and anthophyllite, CAS No. 77536-67-5, (Mg, Fe)₇Si₈O₂₂(OH)₂; are less-used industrially but can still be found in a variety of construction materials and insulation materials and occur in a few consumer products, such as talcum powders and vermiculite. In 1989, In the United States, the Environmental Protection Agency (EPA) passed the Asbestos Ban and Phase Out Rule which was subsequently overturned in 1991. This ruling leaves many consumer product that can still legally contain asbestos. For a clarification of products which legally contain asbestos visit the EPA's clarification statement: http://www.epa.gov/asbestos/pubs/asbbans2.pdf

Historic usage

Items made of asbestos were held in so great an esteem as to be of equal value with gold; none but emperors and kings had napkins made of it. Some antiquaries have believed that ancients made shrouds of asbestos, wherein they burnt the bodies of their kings, in order to entirely preserve their ashes, and prevent their being mixed with those of wood, or other combustible materials commonly used in building funeral piles.^[1]

Others assert that the ancients used asbestos to make perpetual wicks for sepulchral lamps. In more recent centuries, asbestos was indeed used for this purpose. Although asbestos causes skin to itch upon contact, ancient literature 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 alumen plumosum, because the two terms have often been confused throughout history.^[1

Modern usage

Serpentine group

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:

• sheetrock taping
• mud and texture coats
• vinyl floor tiles, sheeting, adhesives and ceiling tiles
• plasters and stuccos
• roofing tars, felts, and shingles
• "transite" panels, siding, countertops, and pipes
• acoustical ceilings
• fireproofing
• putty
• caulk
• gaskets
• brake pads and shoes
• clutch plates
• stage curtains
• fire blankets

Amphibole group

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:

• Low density insulation board and ceiling tiles
• asbestos cement sheets and pipes for construction, casing for water and electrical/telecommunication services
• thermal and chemical insulation (i.e., fire rated doors, limpet spray, lagging and gaskets)

Asbestos-related diseases

Asbestos as a contaminant

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, just 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.^{[citation needed]}

As they get smaller and lighter, they become more mobile and more easily entrained (wafted) into the air, where human respiratory exposures typically result.^{[citation needed]} The released fibers being heavier than air will eventually settle in quiescent conditions only to be re-suspended over and over again by any kind of activity or air currents over a period of time. This cyclic re-entrainment has consequences. Consistent with the tenets of the Second Law of Thermodynamics, the smallest sizes of easily mobile asbestos fibers move away from their initial source location in an ever-broadening manner..^{[citation needed]} They disperse both by simple spontaneous airborne diffusion and through mass transport of the fibers. This latter is an energy-driven process that can occur through directed air currents or by "pickup and release" along a pathway of directed movement by persons, mechanical equipment or vehicles.^{[citation needed]}

For these reasons, asbestos is not an even source of contamination and thus does not tend to remain localized at its initial release point but will eventually spread throughout all available accessible areas of buildings, even into areas that don't have their own asbestos-containing products.^{[citation needed]} Eventually asbestos from virtually all products that were manufactured from this mineral will invade each and every space within an affected building.^{[citation needed]} This is because during the lifecycle of each asbestos product, microscopic fibers and larger particles or pieces of these products are typically produced during their residency.^{[citation needed]} The lifecycle of an asbestos containing product begins from the initial delivery of the product to the building, followed by its installation, normal usage forces, age-related deterioration, physical or chemical damage that often occurs, to finally its removal either for replacement or demolition. Any small impact or damage to a typical asbestos containing product can easily release billions to trillions of fibers of asbestos into the immediate environment which then add to the pool of similar fibers and particles from other asbestos containing products within that building.^{[citation needed]}

Friability of an asbestos containing product means that it is so soft and weak in structure that it can be broken with simple finger crushing pressure.^{[citation needed]} Friable materials are of the most initial concern due to their ease of damage. But non-friable asbestos containing materials are not necessarily safe.^{[citation needed]} The forces or conditions of usage that come into intimate contact with most non-friable asbestos containing materials are substantially higher than finger pressure. Because of this, non-friable asbestos products can and do release substantial quantities of free asbestos fibers into their environments as well.^{[citation needed]} During normal usage, initially non-friable products slowly change into a quasi-friable condition.^{[citation needed]} Asphalt asbestos floor tiles are typically worn down through a sanding action of the normal floor grit under foot traffic on such floor coverings.^{[citation needed]} Asbestos shingles, siding and roofing materials are eroded through drying, weathering, embrittlement, acid rain leaching and other deteriorative changes to their binder matrix resulting in release of asbestos fibers ("chalk dust") when simple contact is made with their surface or when the wind blows across them.^{[citation needed]} Most government regulations treat such products with much less care than they do when addressing more friable products.^{[citation needed]}

Diseases caused by asbestos

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 problem with asbestos arises when the fibers become airborne and are inhaled. Because of the size of the fibers, the lungs cannot expel them. [Casarrett & Doull's Toxicology (2001), pp 520-522]

Diseases caused by asbestos include[3][4]:

• Asbestosis – A lung disease first found in naval shipyard workers, asbestosis is a scarring of the lung tissue from an acid produced by the body's attempt to dissolve the fibers. The scarring may eventually become so severe that the lungs can no longer function. The latency period (the time it takes for the disease to develop) is often 10-20 years.
• Mesothelioma – A cancer of the mesothelial lining of the lungs and the chest cavity, the peritoneum (abdominal cavity) or the pericardium (a sac surrounding the heart). The only known cause is from asbestos exposure. The latency period for mesothelioma may be 20-50 years. The prognosis for mesothelioma is grim, with most patients dying within 12 months of diagnosis.

• Cancer – Cancer of the lung, gastrointestinal tract, kidney and larynx have been linked to asbestos. The latency period for cancer is often 15-30 years. [5]

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

Other asbestos-related diseases

• asbestos warts – caused when the sharp fibres lodge in the skin and are overgrown causing benign callus-like growths.

• pleural plaques – discrete fibrous or partially calcified thickened area which can be seen on X-rays of individuals exposed to asbestos. They do not generally become malignant or cause other lung impairment.

• diffuse pleural thickening – similar to above and can sometimes be associated with asbestosis. Usually no symptoms shown but if extensive can cause lung impairment.

Litigation

Main article: Asbestos and the law

Asbestos litigation is the longest, most expensive mass tort in U.S. history, involving more than 6,000 defendants and 600,000 claimants.[6] Current trends indicate that the rate at which people are diagnosed with the disease will likely increase through the next decade. Analysts have estimated that the total costs of asbestos litigation in the USA alone will eventually reach $200 billion.

While there is no medical dispute about the dangers of inhaled asbestos, the sheer volume of the liability has alarmed the manufacturers and insurance industry. 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.

Personal Injury Accident Claims  No Win No Fee Personal Injury Compensation Solicitors.

Calling all Lawyers!
We need to get in touch with US and UK lawyers who can offer good legal advice to the public about Carbon Monoxide Poisoning.
Please contact us here if you can help us.

What is Carbon Monoxide?

Detectors

Dr David Penney

Buy CO Detectors

Hyperbaric Help Channel

Stories and Letters

NYC Carbon Monoxide Law

Carbon Monoxide & Health Links

Caravan Safety