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The Dangers of Exposure to Asbestos

Before it was banned asbestos was still used in a variety of commercial products. Research suggests that exposure to asbestos can cause cancer as well as other health issues.

You cannot tell by just taking a look at something if it contains asbestos. Also, you cannot taste or smell it. It is only visible when asbestos-containing materials are drilled, chipped or broken.

Chrysotile

At its peak, chrysotile accounted for 99% of the asbestos made. It was widely used in industries including construction insulation, fireproofing and insulation. If workers are exposed to asbestos, they are likely to develop mesothelioma or other asbestos-related illnesses. Since the 1960s, when mesothelioma was first becoming an issue asbestos law use has been drastically reduced. However, trace amounts of it are still found in common products that we use in the present.

Chrysotile is safe to use provided you have a comprehensive safety and handling plan in place. It has been determined that at the current controlled exposure levels, there isn't an danger to those handling the substance. Lung cancer, lung fibrosis and mesothelioma were all linked to breathing in airborne respirable fibres. This has been proven for intensity (dose) as well as the duration of exposure.

In one study, mortality rates were compared between a manufacturing facility that used a large proportion of Chrysotile in the production of friction materials and the national death rate. The study concluded that, after 40 years of processing at low levels of chrysotile there was no significant increase in mortality rates in this factory.

As opposed to other forms of asbestos, chrysotile fibres tend to be shorter. They can pass through the lungs, and even enter the bloodstream. This makes them more likely to cause health effects than fibres with longer lengths.

It is very difficult for chrysotile fibres be airborne or pose any health risk when mixed with cement. Fibre cement products have been extensively used all over the world, especially in buildings like hospitals and schools.

Research has proven that chrysotile has a lower chance to cause illness than amphibole asbestos, such as amosite and crocidolite. Amphibole types like these are the main cause of mesothelioma and other asbestos-related diseases. When chrysotile gets mixed with cement, it forms a strong, flexible building product that is able to withstand severe conditions in the weather and other environmental hazards. It is also easy to clean after use. Professionals can safely remove asbestos fibres once they have been removed.

Amosite

Asbestos is a class of fibrous silicates found in certain types rock formations. It consists of six general groups: serpentine, amphibole anthophyllite, tremolite, anthophyllite, crocidolite (IARC, 1973).

Asbestos minerals are made up of thin, long fibers that range in length from fine to wide. They can be curled or straight. They are present in nature in the form of individual fibrils or bundles with splaying ends called a fibril matrix. Asbestos minerals can be found as a powder (talc) or mixed with other minerals and sold as vermiculite and talcum powder which are widely used in consumer products such as baby powder, face powder and cosmetics.

The largest use of asbestos attorney occurred in the first two-thirds of 20th century where it was used in shipbuilding, insulation, fireproofing, and other construction materials. Most occupational exposures were asbestos fibres in the air, however some workers were exposed vermiculite or talc that was contaminated, and to fragments of asbestos-bearing rock (ATSDR, 2001). Exposures varied from industry to industry, era to era and also from geographical location.

Asbestos exposure in the workplace is mostly due to inhalation. However there are workers who have been exposed through skin contact or by eating food items contaminated with asbestos. Asbestos is currently only found in the the natural weathering of mined minerals and the degrading of contaminated materials such as insulation, car brakes, clutches, and floor and ceiling tiles.

There is evidence to suggest that amphibole fibres from non-commercial sources could also be carcinogenic. These are fibres don't form the tightly weaved fibrils of amphibole and serpentine minerals but instead are flexible, loose and needle-like. These fibers can be found in mountain sandstones, cliffs and sandstones of a variety of countries.

Asbestos is able to enter the environment in many ways, including through airborne particles. It can also be released into soil or water. This can be caused by both natural (weathering of asbestos-bearing rock) and anthropogenic sources (disintegration of asbestos-containing wastes and disposal in landfill sites). Asbestos contamination in ground and surface waters is primarily due to natural weathering. However, it has also been caused anthropogenically, such as through milling and mining of asbestos-containing materials demolition and dispersal and the disposal of contaminated dumping material in landfills (ATSDR 2001). Asbestos fibres that are emitted from the air are the main reason for illness among those exposed to it in their job.

Crocidolite

Inhalation exposure is the most common method of exposure to asbestos fibres. These fibres can infiltrate the lung which can cause serious health issues. Mesothelioma and asbestosis as well as other illnesses are all caused by asbestos fibres. Exposure to the fibres can be triggered in other ways, like contact with contaminated clothing or building materials. This type of exposure is more dangerous when crocidolite (the blue asbestos form) is involved. Crocidolite fibers are less dense and more fragile and therefore easier to breathe in. They can also lodge deeper within lung tissue. It has been linked to more mesothelioma-related cases than other asbestos types.

The six major types are chrysotile, amosite and chrysotile. The most commonly used forms of asbestos are epoxiemite and chrysotile, which together make up 95% all commercial asbestos used. The other four asbestos types are not as prevalent, but could still be present in older structures. They are not as hazardous as amosite and chrysotile, but they can pose a risk when combined with other asbestos minerals, or when mined close to other naturally occurring mineral deposits, like vermiculite or talc.

Numerous studies have revealed the connection between stomach cancer and asbestos exposure. The evidence isn't unanimous. Some researchers have cited an SMR (standardized death ratio) of 1.5 (95 percent confidence interval: 0.7-3.6), for all asbestos legal workers, while others report an SMR of 1,24 (95 percent confidence interval: 0.76-2.5), for those working in mines and chrysotile mills.

The International Agency for Research on Cancer (IARC) has classed all forms of asbestos as carcinogenic. All forms of asbestos could cause mesothelioma or other health problems, but the risk is dependent on the amount of exposure that people are exposed to, the type of asbestos used, the duration of their exposure, and the manner in the way that it is breathed in or consumed. The IARC has advised that abstaining from all asbestos forms should be the highest priority, as this is the safest option for individuals. If you have been exposed in the past to asbestos and are suffering from a respiratory disorder or mesothelioma condition, then you should see your physician or NHS111.

Amphibole

Amphiboles comprise a variety of minerals which can form needle-like or prism-like crystals. They are an inosilicate mineral that is composed of two chains of SiO4 molecules. They typically possess 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 a ring of six tetrahedrons. The tetrahedrons can be separated from one another by strips of octahedral sites.

Amphibole minerals are common in igneous and metamorphic rocks. They are usually dark and hard. Due to their similarity of hardness and colour, they can be difficult for some to differentiate from the pyroxenes. They also share a corresponding design of cleavage. Their chemistry allows for a variety of compositions. The chemical compositions and crystal structures of the different mineral groups in amphibole can be used to determine their composition.

Amphibole asbestos is comprised of chrysotile as well as the five types of asbestos amosite, anthophyllite (crocidolite), amosite (actinolite), and amosite. While the most popular asbestos type is chrysotile; each is unique in its own way. Crocidolite is the most hazardous asbestos kind. It has sharp fibers which are easily breathed into the lungs. Anthophyllite is brown to yellowish in color and is composed of iron and magnesium. This variety was used to make cement and insulation materials.

Amphibole minerals are hard to analyze because they have a an intricate chemical structure and a variety of substitutions. Therefore, a thorough analysis of their composition requires specialized methods. EDS, WDS and XRD are the most widely used methods of identifying amphiboles. However, these methods can only provide approximate identifications. For instance, they are unable to distinguish between magnesio-hastingsite from magnesio-hornblende. These techniques also do not distinguish between ferro-hornblende and pargasite.