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The Dangers of Exposure to Asbestos

Asbestos was used in thousands of commercial products prior to when it was banned. Research suggests that exposure to asbestos litigation (additional resources) can cause cancer and other health problems.

It is not possible to tell by simply looking at something whether it is made of asbestos. Neither can you smell or taste it. Asbestos is only detected when the material containing it is broken, drilled, or chipped.

Chrysotile

At its height, chrysotile was responsible for 95% of the asbestos created. It was widely used in industries like construction, insulation, and asbestos litigation fireproofing. If workers were exposed to this toxic material, they may develop mesothelioma or other asbestos related diseases. Thankfully, the use of this harmful mineral has diminished significantly since awareness of mesothelioma began to spread in the 1960's. It is still present in many products we use in the present.

Chrysotile can be safely used with a well-thought-out safety and handling plan is put into place. It has been determined that at the current controlled exposure levels, there is no unneeded risk to the people handling the substance. Lung fibrosis, lung cancer and mesothelioma are all associated with breathing in airborne respirable fibres. This has been confirmed in terms of intensity (dose) as in the time of exposure.

In one study, mortality rates were compared among a factory which used largely chlorosotile to make friction materials and national death rates. It was found that for the 40 years of processing asbestos chrysotile in low levels of exposure there was no significant additional mortality in this factory.

Unlike some other forms of asbestos, chrysotile fibres tend to be smaller. They can enter the lungs, and enter the bloodstream. They are more likely to cause health issues than fibres with longer lengths.

It is very difficult for chrysotile fibres be a threat to the air or pose any health risk when mixed with cement. Fibre cement products are used extensively throughout the world particularly in buildings such as schools and hospitals.

Studies have shown that chrysotile has a lower chance to cause disease than amphibole asbestos such as crocidolite and amosite. These amphibole types have been the primary cause of mesothelioma and other asbestos-related diseases. When cement and chrysotile are mixed with cement, a tough and flexible material is created that can withstand extreme weather conditions and environmental hazards. It is also very easy to clean after use. Asbestos fibres can be easily removed by a professional and then safely eliminated.

Amosite

Asbestos refers to a group of silicate minerals with fibrous structure which are found naturally in a variety of types of rock formations. It consists of six general groups: serpentine, amphibole as well as tremolite, anthophyllite, and crocidolite (IARC 1973).

Asbestos minerals comprise long, thin fibers that range in length from fine to wide. They can also be straight or curled. They can be found in nature in bundles or as individual fibrils. Asbestos minerals can also be found as a powder (talc) or mixed with other minerals and sold as vermiculite and talcum powder that are widely used in consumer products such as baby powder, face powder and cosmetics.

The largest use of asbestos was in the first two-thirds period of the 20th century in the period when it was employed in shipbuilding, insulation, fireproofing and other construction materials. Most occupational exposures were to asbestos fibres in the air, however certain workers were exposed to toxic talc or vermiculite and to pieces of asbestos-bearing rock (ATSDR 2001). Exposures varied according to the industry, time frame, and geographic location.

Asbestos exposure in the workplace is usually because of inhalation. However there have been instances of workers being exposed through contact with skin or eating food that is contaminated. Asbestos is only found in the environment because of natural weathering and degrading of contaminated materials like ceiling and floor tiles, car brakes and clutches, as well as insulation.

It is becoming increasingly apparent that non-commercial amphibole fibers can also be carcinogenic. These are fibres that are not the tightly interwoven fibrils that are found in the amphibole and serpentine minerals, but instead are loose, flexible and needle-like. These fibers are found in the mountain sandstones, cliffs and sandstones of a variety of countries.

Asbestos may enter the environment in many ways, including through airborne particles. It can also be released into soil or water. This can be caused by natural (weathering and erosion of asbestos-bearing rocks) and the anthropogenic (disintegration and removal of asbestos-containing wastes from landfill sites) sources. Asbestos contamination in surface and ground water is mostly caused by 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 waste in landfills (ATSDR 2001). Airborne asbestos fibres are the most significant reason for illness among those exposed to asbestos claim in their work.

Crocidolite

Inhalation exposure to asbestos is the most frequent method by which people are exposed to the harmful fibres that can be absorbed into the lungs and cause serious health problems. Mesothelioma as well as asbestosis and other diseases are caused by asbestos fibres. The exposure to asbestos fibres could be triggered in other ways, such as contact with contaminated clothing or building materials. The dangers of exposure are greater when crocidolite which is the asbestos that is blue, is involved. Crocidolite fibers are thinner and more fragile making them more palatable to breathe in. They also can get deeper in lung tissue. It has been linked to more mesothelioma-related cases than other types of asbestos.

The six major types of asbestos are chrysotile amosite and tremolite. They are epoxiemite, tremol anthophyllite, and actinolite. Chrysotile and amosite are the most frequently used types of asbestos, and comprise 95% of asbestos used in commercial construction. The other four asbestos types aren't as common, but may still be present in older structures. They are less hazardous than chrysotile and amosite, but they can pose a risk when combined with other asbestos minerals or when mined in close proximity to other naturally occurring mineral deposits, like talc or vermiculite.

Many studies have discovered an connection between exposure to asbestos and stomach cancer. However the evidence isn't conclusive. Some researchers have cited an SMR (standardized death ratio) of 1.5 (95% confidence interval: 0.7-3.6), for all asbestos workers. However, others have reported an SMR of 1,24 (95 percent confidence interval: 0.76-2.5), for those who work in chrysotile mills and mines.

IARC the International Agency for Research on Cancer, has classified all forms of asbestos compensation as carcinogenic. All forms of asbestos could cause mesothelioma as well as other health issues, but the risks vary according to the amount of exposure people are exposed to, the type of asbestos used as well as the duration of exposure and the way in which it is inhaled or ingested. The IARC has recommended that the prevention of all asbestos types is the best option, as this is the most secure option for individuals. However, if people have been exposed to asbestos in the past and suffer from an illness such as mesothelioma, or other respiratory conditions it is recommended that they seek advice from their doctor or NHS 111.

Amphibole

Amphibole is a group of minerals that form long prisms or needle-like crystals. They are an inosilicate minerals made of double chains of SiO4 molecules. They have a monoclinic structure of crystals, however some have an orthorhombic shape. The general formula of an amphibole is A0-1B2C5T8O22(OH,F)2. The double chains are composed of (Si, Al)O4 tetrahedrons linked together in a series of six tetrahedrons. The tetrahedrons can be separated from one another by octahedral sites that are surrounded by strips.

Amphibole minerals are prevalent in metamorphic and igneous rocks. They are usually dark-colored and tough. Due to their similarity in strength and color, they may be difficult for some people to distinguish from pyroxenes. They also share a similar design of cleavage. However, their chemistry allows for many different compositions. The chemical compositions and crystal structure of the various minerals 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 commonly used form of asbestos is chrysotile each type has distinct characteristics. The most dangerous type of asbestos legal, crocidolite, is made up of sharp fibers that are easy to breathe into the lungs. Anthophyllite is a brownish to yellowish color and is made mostly of iron and magnesium. This type of stone was once used in cement-based products and insulation materials.

Amphiboles are difficult to analyze due to their complex chemical structure and the numerous substitutions. A thorough analysis of composition of amphibole minerals requires special methods. The most popular methods to identify amphiboles are EDS, WDS, and XRD. However, these methods only provide approximate identifications. For instance, these techniques are unable to distinguish between magnesio-hastingsite from magnesio-hornblende. Furthermore, these techniques do not distinguish between ferro hornblende and pargasite.