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The Dangers of Exposure to Asbestos

Asbestos was used in a variety of commercial products before it was banned. According research, exposure to asbestos can cause cancer, as well as other health problems.

You can't tell if something is asbestos-containing by looking at it and you can't smell or taste it. Asbestos is only detected when the materials that contain it are broken, drilled, or chipped.

Chrysotile

At its height, chrysotile was responsible for 99percent of the asbestos produced. It was employed in a variety of industries including construction insulation, fireproofing, and insulation. If workers were exposed to the toxic substance, asbestos they could develop mesothelioma and other asbestos-related diseases. Since the 1960s, when mesothelioma was first becoming a major concern asbestos use has been drastically reduced. However, trace amounts are still found in many of the products we use today.

Chrysotile is safe to use provided you have a comprehensive safety and handling program in place. People who handle chrysotile do not exposed to an unreasonable amount of risk at the present safe exposure levels. The inhalation of airborne particles has been strongly associated with lung cancer and lung fibrosis. This has been proven for both intensity (dose) and time of exposure.

A study that looked at the operation of a factory that utilized almost all chrysotile as its friction materials, compared the mortality rates of this factory with national mortality rates. It was found that for 40 years of processing chrysotile asbestos at low levels of exposure there was no significant increase in mortality in this particular factory.

Chrysotile fibres are usually shorter than other types of asbestos. They can penetrate the lungs, and then pass through the bloodstream. They are more likely to cause health issues than longer fibres.

When chrysotile mixes with cement, it's very difficult for the fibres to become airborne and pose any health risk. The fibre cement products are extensively used all over the world particularly in buildings like hospitals and schools.

Research has revealed that amphibole asbestos like amosite or crocidolite is not as likely to cause disease. Amphibole asbestos types have been the primary cause of mesothelioma as well as other asbestos attorney-related illnesses. When chrysotile gets mixed with cement, it creates an extremely durable and flexible building product that is able to withstand severe conditions in the weather and other environmental dangers. It is also easy to clean after use. Asbestos fibres can easily be removed by a professional and safely disposed of.

Amosite

Asbestos is a term used to describe a class of silicate mineral fibrous that occur naturally in certain types of rock formations. It consists of six general groups: serpentine, amphibole anthophyllite, tremolite and crocidolite (IARC, 1973).

Asbestos minerals are made up of thin, long fibres that range in length from very fine to wide and straight to curled. They can be found in nature in bundles, or as individual fibrils. Asbestos minerals are also found in powder form (talc) or mixed with other minerals and sold as vermiculite and talcum powder, which have been widely used in consumer products such as baby powder, face powder and cosmetics.

Asbestos was used extensively in the first two thirds of the 20th century for shipbuilding as well as insulation, fireproofing and other construction materials. The majority of occupational exposures involved asbestos fibres borne by air, but some workers were exposed to vermiculite or talc that was contaminated and also to fragments of asbestos-bearing rocks (ATSDR, 2001). Exposures varied from industry to industry, from era to and geographic location.

Most asbestos exposures at work were due to inhalation, but certain workers were exposed through contact with skin or by eating food contaminated with asbestos. Asbestos can only be found in the air due to natural weathering and degrading of contaminated materials, such as ceiling and floor tiles, car brakes and clutches as well as insulation.

There is growing evidence that non-commercial amphibole fibres may also be carcinogenic. These are fibres that do not form the tightly interwoven fibrils that are found in the amphibole and serpentine minerals but instead are loose, flexible and needle-like. They can be found in cliffs, mountains and sandstones of a variety of countries.

Asbestos enters the environment mainly as airborne particles, but it can also be absorbed into soil and water. This can be triggered by both natural (weathering of asbestos-bearing rocks) as well as anthropogenic sources (disintegration of asbestos-containing wastes as well as disposal in landfill sites). Asbestos contamination in ground and surface waters is primarily caused by natural weathering. However it can also be caused by humans, such as through milling and mining of asbestos-containing materials demolition and dispersal and the disposal of contaminated dumping materials in landfills (ATSDR 2001). Airborne asbestos fibres are the primary cause of illness in people exposed to asbestos during their occupation.

Crocidolite

Exposure to asbestos through inhalation is the most frequent method by which people are exposed to the harmful fibres, which could then get into the lungs and cause serious health issues. Mesothelioma, asbestosis, and other illnesses are all caused by asbestos fibres. Exposure to fibres can occur in other ways as well, for example, contact with contaminated clothing, or building materials. This type of exposure is more hazardous when crocidolite (the blue asbestos form) is involved. Crocidolite has smaller, more fragile fibers, which are easier to inhale and can lodge deeper into lung tissue. It has been associated with a higher number of mesothelioma-related cases than any other form of asbestos.

The main types are chrysotile and amosite. The most popular asbestos types are chrysotile and epoxiemite, which together comprise the majority of commercial asbestos used. The other four types haven't been as widely utilized however, they could be found in older buildings. They are less dangerous than chrysotile or amosite but can still be dangerous when mixed with other minerals, or when mined near other mineral deposits, such as talc and vermiculite.

Numerous studies have shown the connection between stomach cancer and asbestos exposure. However the evidence isn't conclusive. Some researchers have cited an SMR (standardized mortality ratio) of 1.5 (95% 95% confidence interval: 0.7-3.6) for all asbestos-related workers, while others have reported an SMR of 1.24 (95 percent 95% CI: 0.76-2.5) for workers working in chrysotile mining and mills.

IARC The IARC, which is the International Agency for Research on Cancer has classified all forms of asbestos as carcinogenic. All kinds of asbestos may cause mesothelioma and other health problems, but the risks differ based on the amount of exposure people are exposed to, the type of asbestos involved as well as the duration of exposure and the manner in which it is breathed in or consumed. IARC has stated that the best option for individuals is to avoid all forms of asbestos. However, if a person has been exposed to asbestos in the past and suffer from an illness, such as mesothelioma or other respiratory ailments it is recommended that they seek advice from their GP or NHS 111.

Amphibole

Amphiboles are a grouping of minerals which can create prism-like or needle-like crystals. They are a kind of inosilicate mineral made up of double chains of molecules of SiO4. They usually have a monoclinic crystal system however some may have an orthorhombic structure. The general formula of an amphibole is A0-1B2C5T8O22(OH,F)2. Double chains contain (Si, Al)O4 tetrahedrons linked together in rings of six tetrahedrons. Tetrahedrons are distinguished from one another with octahedral strips.

Amphibole minerals are common in igneous and metamorphic rocks. They are typically dark and hard. They are sometimes difficult to distinguish from pyroxenes due to their similar hardness and color. They also share a similar pattern of cleavage. Their chemistry allows a wide range of compositions. The various mineral groups in amphibole can be identified by their chemical compositions as well as crystal structures.

The five types of asbestos belonging to the amphibole family are amosite, anthophyllite as well as crocidolite and actinolite. While the most commonly used asbestos type is chrysotile. Each variety has its own unique characteristics. Crocidolite is the most dangerous asbestos kind. It has sharp fibers that can easily be breathed into the lungs. Anthophyllite is yellowish to brown in color and is made up of magnesium and iron. This type of stone was once used in cement and insulation materials.

Amphibole minerals are hard to analyze due to their an intricate chemical structure and numerous substitutions. Therefore, a thorough analysis of their composition requires specialized techniques. EDS, WDS and XRD are the most commonly used methods for identifying amphiboles. These methods are only able to provide approximate identifications. For instance, these methods cannot distinguish between magnesiohastingsite and magnesio-hornblende. Moreover, these techniques do not distinguish between ferro-hornblende and pargasite.