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The Dangers of Exposure to Asbestos

Asbestos was a component in thousands of commercial products prior asbestos to when it was banned. Studies have shown that exposure to asbestos can cause cancer and other health issues.

It is difficult to tell if something is asbestos-containing by looking at it and you can't smell or taste it. It can only be found when materials containing asbestos are chipped, drilled or broken.

Chrysotile

At its height, chrysotile provided for 95% of the asbestos produced. It was employed in many industries including construction insulation, fireproofing, as well as insulation. If workers are exposed to asbestos, they can develop mesothelioma or other asbestos-related diseases. Since the 1960s, when mesothelioma began to become a problem the use of asbestos has decreased significantly. It is still present in many products we use in the present.

Chrysotile is safe to use provided you have a comprehensive safety and handling program in place. It has been found that at the current controlled exposure levels, there is no danger to those handling the substance. Inhaling airborne fibres has been linked with lung cancer and lung fibrosis. This has been confirmed for both intensity (dose) and the duration of exposure.

One study that examined a facility that used nearly exclusively chrysotile for manufacturing friction materials, compared mortality rates at this factory with national mortality rates. It was discovered that, over the course of 40 years, processing chrysotile asbestos at low levels of exposure, there was no significant increase in mortality in this particular factory.

Unlike some other forms of asbestos, chrysotile fibers tend to be shorter. They are able to enter the lungs and enter the bloodstream. This makes them much more likely to cause health effects than fibres with longer lengths.

It is extremely difficult for chrysotile fibers to be inhaled or to pose a health risk when mixed with cement. The fibre cement products are used extensively throughout the world particularly in structures like hospitals and schools.

Research has shown that chrysotile is less likely to cause disease than amphibole asbestos, such as crocidolite and amosite. These amphibole kinds have been the main source of mesothelioma, as well as other asbestos-related illnesses. When cement and chrysotile are mixed with cement, a tough and flexible material is created that is able to withstand extreme weather conditions and environmental hazards. It is also easy to clean after use. Professionals can safely eliminate asbestos fibres when they have been removed.

Amosite

Asbestos refers to a group of fibrous silicate minerals that occur naturally in certain kinds of rock formations. It is divided into six groups which include amphibole (serpentine), the tremolite (tremolite) anthophyllite (crocidolite) and anthophyllite.

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

The largest use of asbestos was in the early two-thirds of the twentieth century, when it was used in shipbuilding, insulation, fireproofing, and other construction materials. Most occupational exposures were to asbestos fibres in the air, however some workers were exposed contaminated vermiculite or talc as well as to fragments of asbestos-bearing rocks (ATSDR 2001). Exposures varied by the industry, time frame, and geographic location.

Most of the asbestos exposures that workers were exposed to was caused by inhalation, however certain workers were exposed by skin contact or through eating contaminated food. Asbestos is now only found in the environment due to natural weathering of mined ores and the deterioration of products contaminated with asbestos such as insulation, car brakes and clutches and ceiling and floor tiles.

It is becoming apparent that non-commercial amphibole fibres may also be carcinogenic. These are fibres do not have the tight interwoven fibrils that are found in the amphibole or serpentine minerals but instead are flexible, loose and needle-like. These fibers can be found in mountains, sandstones, and cliffs from a variety of nations.

Asbestos can be found in the environment as airborne particles, but it also leaches into water and soil. This is a result of both natural (weathering and asbestos erosion of asbestos-bearing rocks) and human-caused (disintegration and disposal of asbestos-containing materials in landfill sites) sources. Asbestos contamination in surface and ground waters is primarily caused through natural weathering. However it is also caused by anthropogeny, such as through milling and mining of asbestos-containing materials demolition and dispersal and the removal of contaminated dumping material in landfills (ATSDR 2001). Asbestos fibres that are emitted from the air are the most significant cause of disease among those who are exposed to it during their occupation.

Crocidolite

Exposure to asbestos through inhalation is the most frequent way people are exposed harmful fibres that can then be inhaled and cause serious health issues. These include asbestosis and mesothelioma. Exposure to fibers can occur in other ways as well, for example, contact with contaminated clothing or building materials. This type of exposure is especially dangerous when crocidolite (the blue form of asbestos case) is involved. Crocidolite fibers are smaller and more fragile, making them easier to breathe in. They can also be lodged deeper within lung tissue. It has been linked to more mesothelioma-related cases than other types of asbestos.

The six major types are chrysotile as well as amosite. Amosite and chrysotile are two of the most commonly used types of asbestos, and comprise 95% of the commercial asbestos that is used. The other four asbestos types are not as well-known, but can still be present in older structures. They are less dangerous than chrysotile and amosite, but they may pose a danger when mixed with other asbestos minerals, or when mined in close proximity to other mineral deposits, such as talc or vermiculite.

A number of studies have demonstrated an association between exposure to asbestos and stomach cancer. The evidence isn't conclusive. Some researchers have reported an SMR (standardized mortality ratio) of 1.5 (95 percent of the time CI: 0.7-3.6) for all asbestos-related workers, while others have reported an SMR of 1.24 (95% 95% CI: 0.76-2.5) for workers working in chrysotile mining and mills.

The International Agency for Research on Cancer (IARC) has classed all forms of asbestos as carcinogenic. All asbestos types can cause mesothelioma however, the risk is dependent on how much exposure, what kind of asbestos is involved and how long the exposure lasts. The IARC has advised that the prevention of all asbestos types is the best option because this is the most safe option for individuals. However, if someone has been exposed to asbestos in the past and are suffering from an illness such as mesothelioma, or other respiratory ailments and require advice, they should seek out guidance from their GP or NHS 111.

Amphibole

Amphibole is a class of minerals that form long prisms or needle-like crystals. They are a type of inosilicate mineral that is composed of double chains of molecules of SiO4. They typically have a monoclinic crystal system, although some have an orthorhombic structure. The general formula of an amphibole is A0-1B2C5T8O22(OH,F)2. The double chains comprise (Si, Al)O4 tetrahedrons linked together in rings of six tetrahedrons. Tetrahedrons can be separated by octahedral strips.

Amphibole minerals are common in metamorphic and igneous rocks. They are typically dark and hard. They are sometimes difficult to distinguish from pyroxenes due to their similar hardness and colors. They also share a similar cleavage. However their chemistry permits many different compositions. The chemical compositions and crystal structures of the various mineral groups in amphibole can be used to identify them.

Amphibole asbestos consists of chrysotile, and the five types of asbestos amosite anthophyllite (crocidolite), amosite (actinolite) and amosite. Each type of asbestos comes with its own distinct properties. The most dangerous form of asbestos, crocidolite is made up of sharp fibers that are easy to inhale into the lungs. Anthophyllite is brown to yellowish in color and is made up of iron and magnesium. This variety was once used in products such as cement and insulation materials.

Amphibole minerals are difficult to study because of their complex chemical structures and many substitutions. Therefore, a thorough analysis of their composition requires special methods. The most widely used methods of identifying amphiboles include EDS, WDS, and XRD. However, these methods can only provide approximate identifications. For example, these techniques cannot differentiate between magnesio-hastingsite and magnesio-hornblende. These techniques do not differentiate between ferro-hornblende or pargasite.