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The Dangers of Exposure to Asbestos

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

You cannot tell by just looking at something whether it is made up of asbestos. It is also impossible to smell or taste it. Asbestos can only be detected when the substances that contain it are broken or drilled.

Chrysotile

At its height, chrysotile comprised up 99% of the asbestos produced. It was used in many industries like construction, insulation, and fireproofing. In the event that workers were exposed to the toxic material, they could contract mesothelioma, as well as other asbestos-related diseases. Since the 1960s, when mesothelioma began to become a major concern, the use of asbestos has decreased significantly. However, trace amounts of it are still present in the products we use today.

Chrysotile can be safely used in the event that a thorough safety and handling plan is put in place. It has been found that, at today's controlled exposure levels, there isn't an undue risk to the workers handling the substance. Lung fibrosis, lung cancer and mesothelioma are all associated with breathing in airborne respirable fibres. This has been proven to be true for both intensity (dose) and time of exposure.

In one study, mortality rates were compared between a factory which used almost exclusively chlorosotile to make friction materials and national death rates. It was concluded that for 40 years of preparing asbestos chrysotile at low levels of exposure, there was no significant extra mortality in the factory.

As opposed to other forms of asbestos, chrysotile fibres tend to be smaller. They can penetrate the lungs and enter the bloodstream. They are more likely to cause health problems than fibres that are longer.

It is very difficult for chrysotile fibers to be airborne or pose any health risk when mixed with cement. Fibre cement products are extensively used in a variety of locations around the world including hospitals and schools.

Research has demonstrated that amphibole asbestos, like crocidolite or amosite is less likely than chrysotile in causing diseases. These amphibole types have been the most common cause of mesothelioma as well as other asbestos-related diseases. When cement and chrysotile are mixed and cured, a tough and flexible product is created that can withstand extreme environmental hazards and weather conditions. It is also easy to clean after use. Asbestos fibers can be easily removed by a professional and eliminated.

Amosite

Asbestos is a class of fibrous silicates that are found in certain types rock formations. It is comprised of six main groups: serpentine, amphibole as well as tremolite, anthophyllite, and crocidolite (IARC 1973).

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

Asbestos was extensively used in the early two-thirds of the 20th century to construct construction of ships, insulation, fireproofing, and other construction materials. The majority of asbestos-containing exposures to the workplace occurred in the air, but some workers also were exposed to asbestos-bearing rocks and contaminated vermiculite. Exposures varied by the industry, time frame, and geographic location.

The majority of asbestos-related exposures in the workplace were because of inhalation, but certain workers were exposed through skin contact or by eating food contaminated with asbestos. Asbestos is found in the environment because of natural weathering and degrading of products that are contaminated, such as ceiling and floor tiles cars, brakes and clutches as well as insulation.

There is evidence emerging that non-commercial amphibole fibres may also be carcinogenic. These fibers aren't weaved like the fibrils that are found in amphibole or serpentine, but are instead loose, flexible, and needle-like. These fibres are found in the mountains and cliffs of several countries.

Asbestos gets into the environment primarily in the form of airborne particles, however it can also be absorbed into soil and water. This can be caused by both natural (weathering of asbestos-bearing rock) as well as anthropogenic sources (disintegration of asbestos-containing wastes as well as disposal in landfill sites). Asbestos contamination of surface and ground waters is primarily caused by natural weathering. However it is also caused by humans, such as by the milling and mining of asbestos-containing materials, demolition and dispersal, and the disposal of contaminated dumping materials in landfills (ATSDR 2001). Exposure to asbestos-containing airborne fibres remains the main cause of illness among people exposed to asbestos in the workplace.

Crocidolite

Inhalation exposure is the most frequent method of exposure to asbestos fibres. These fibres can infiltrate the lungs and cause serious health problems. This includes asbestosis and mesothelioma. Exposure to fibres can occur in other ways, too like contact with contaminated clothing or materials. The dangers of this kind of exposure are higher when crocidolite, the asbestos in the blue form is involved. Crocidolite fibers are smaller and more fragile, making them easier to breathe in. They can also be lodged deeper into lung tissues. It has been associated with a higher number of mesothelioma cases than any other form of asbestos.

The six main types of asbestos are chrysotile, amosite and tremolite. They are epoxiemite, tremol anthophyllite, and actinolite. Amosite and chrysotile are the most frequently used types of asbestos litigation and make up 95 percent of all commercial asbestos currently used. The other four have not been as widely utilized however, they could be present in older buildings. They are less dangerous than chrysotile and amosite, but they can pose a risk when mixed with other asbestos minerals or when mined close to other mineral deposits, like talc or vermiculite.

A number of studies have demonstrated an association between exposure to asbestos and stomach cancer. Numerous studies have shown a link between asbestos exposure and stomach. The evidence is contradictory. Certain researchers have cited an SMR (standardized death ratio) of 1.5 (95 percent confidence interval: 0.7-3.6), for all asbestos workers, while others have reported an SMR of 1,24 (95 percent confidence interval: 0.76-2.5), for workers in chrysotile mines and mills.

The International Agency for Research on Cancer (IARC) has classed all asbestos types as carcinogenic. All asbestos types can cause mesothelioma but the risks vary depending on how much exposure, what kind of asbestos is involved and how long the exposure lasts. The IARC has recommended that avoiding all forms of asbestos is the most important thing to do because this is the most secure option for individuals. However, if people have been exposed to asbestos in the past and are suffering from an illness such as mesothelioma and other respiratory illnesses it is recommended that they seek advice from their doctor or NHS 111.

Amphibole

Amphiboles comprise a variety of minerals that may create prism-like or needle-like crystals. They are a type of inosilicate minerals made of double 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. The double chains consist of (Si,Al)O4 Tetrahedrons, which are connected in rings of six. The tetrahedrons are separated from each other with octahedral strips.

Amphiboles occur in both igneous and metamorphic rock. They are usually dark-colored and tough. They can be difficult to differentiate from pyroxenes since they share similar hardness and colors. They also share a similar cleavage. Their chemistry can allow for a variety of compositions. The different mineral groups within amphibole are identified by their chemical compositions as well as crystal structures.

Amphibole asbestos includes chrysotile and the five asbestos types: amosite anthophyllite (crocidolite), amosite (actinolite) and amosite. While the most popular form of asbestos is chrysotile. Each variety has its own unique characteristics. The most hazardous type of asbestos, crocidolite, is composed of sharp fibers that are easy to breathe into the lungs. Anthophyllite can range from yellow to brown in color and is made up of iron and magnesium. This variety was once used in cement-based products and insulation materials.

Amphibole minerals are challenging to analyze due to their an intricate chemical structure and numerous substitutions. A thorough analysis of composition of amphibole minerals requires specialized techniques. The most popular methods of identifying amphiboles include EDS, WDS, and XRD. However, these methods can only give approximate identifications. For instance, these techniques, cannot distinguish between magnesio-hornblende and hastingsite. These techniques also don't differentiate between ferro-hornblende or pargasite.