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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 can cause cancer and other health issues.

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

Chrysotile

At the height of its use, chrysotile made up 99% of the asbestos production. It was widely used in industries such as construction insulation, fireproofing, as well as insulation. If workers were exposed to this harmful material, they may develop mesothelioma and other asbestos-related diseases. Thankfully, the use this toxic mineral has decreased significantly since awareness of mesothelioma began to increase in the 1960's. It is still present in a variety of products we use in the present.

Chrysotile can be used in a safe manner with a well-thought-out safety and handling plan is put into place. Personnel handling chrysotile aren't exposed to an unreasonable amount of risk at the current controlled exposure levels. Lung fibrosis, lung cancer and mesothelioma have been strongly linked to breathing airborne respirable fibres. This has been proven in terms of intensity (dose) as well as duration of exposure.

A study that looked at an industrial facility that used almost all chrysotile as its friction materials compared mortality rates in this factory with national death rates. It was found that over the course of 40 years, processing asbestos chrysotile in low levels of exposure There was no significant increase in mortality in this particular factory.

Chrysotile fibers are generally shorter than other forms of asbestos. They can penetrate the lungs and enter the bloodstream. This makes them more likely to cause ill-health effects than fibrils with a longer length.

It is very difficult for chrysotile fibres to be airborne or pose any health risk when mixed with cement. The fibre cement products are extensively used all over the world particularly in buildings like hospitals and schools.

Research has shown that chrysotile is less prone to cause illness than amphibole asbestos, like crocidolite and amosite. These amphibole varieties are the main source of mesothelioma as well as other asbestos-related diseases. When chrysotile mixes with cement, it forms an extremely durable and flexible building product that can withstand the most extreme conditions in the weather and other environmental dangers. It is also very easy to clean up after use. Professionals can safely remove asbestos fibres once they have been removed.

Amosite

Asbestos is a category of fibrous silicates found in various types of rock formations. It is comprised of six general groups: serpentine, amphibole, tremolite, anthophyllite and crocidolite (IARC, 1973).

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

The greatest use of asbestos was in the early two-thirds of the 20th century, when it was used in shipbuilding, insulation, fireproofing and other construction materials. The majority of occupational exposures were asbestos fibres that were borne in the air, but some workers were exposed to contaminated vermiculite or talc and also to fragments of asbestos-bearing rock (ATSDR 2001). Exposures varied according to the industry, time frame, and geographic location.

Most of the asbestos-related exposures in the workplace were due to inhalation. However, some workers were also exposed by skin contact or through eating contaminated food. Asbestos is only found in the air due to natural weathering and degrading of products that are contaminated like ceiling and floor tiles, car brakes and clutches, and insulation.

There is growing evidence that non-commercial amphibole fibers could also be carcinogenic. They are not tightly weaved like the fibrils in amphibole or serpentine, but are instead loose elastic, flexible, and needle-like. These fibers are found in the mountains and cliffs from a variety of countries.

Asbestos is able to enter the environment in a variety of ways, including as airborne particles. It can also be released into soil or water. This is a result of both natural (weathering and erosion of asbestos-bearing rocks) and ananthropogenic (disintegration and removal of asbestos-containing wastes from landfill sites) sources. Asbestos contamination of surface and ground waters is primarily 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 dumping materials in landfills (ATSDR 2001). Exposure to asbestos-containing airborne fibres is still the primary cause of illness among people exposed to it occupationally.

Crocidolite

Inhalation exposure is the most commonly used method of exposure to asbestos fibres. These fibres can get into the lung and cause serious health issues. This includes asbestosis and mesothelioma. The exposure to asbestos fibres could occur in different ways, like contact with contaminated clothing or building materials. The dangers of this kind of exposure are higher when crocidolite, a asbestos' blue form is involved. Crocidolite is a smaller, more fragile fibers, which are easier to inhale and can lodge deeper in lung tissue. It has been associated with more mesothelioma cancer cases than other asbestos types.

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 case and account for 95 percent of all asbestos used in commercial construction. The other four types of asbestos haven't been as widely used, but they may still be found in older buildings. They aren't as hazardous as chrysotile or amosite but can still be a risk when combined with other minerals or when mined close to other mineral deposits such as vermiculite and talc.

Numerous studies have proven the connection between stomach cancer and asbestos exposure. However, the evidence is contradictory. Certain researchers have reported an SMR (standardized mortality ratio) of 1.5 (95% of the time CI: 0.7-3.6) for all asbestos-related workers as well as an SMR of 1.24 (95% 95% CI: 0.76-2.5) for those working in chrysotile mines and mills.

IARC the International Agency for Research on Cancer, has classified all forms of asbestos carcinogenic. All asbestos types can cause mesothelioma, however, the risk is dependent on the amount of exposure, Asbestos what kind of asbestos is involved, and how long the exposure lasts. IARC has declared that the best choice for people is to avoid all types of asbestos. However, if someone has been exposed to asbestos in the past and suffer from an illness, such as mesothelioma, or other respiratory illnesses and require advice, they should seek out guidance from their physician or NHS 111.

Amphibole

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

Amphiboles occur in metamorphic and igneous rock. They are typically dark and hard. They are sometimes difficult to distinguish from pyroxenes as they share similar hardness and color. They also share a similar Cleavage. However their chemistry permits an array of compositions. The chemical compositions and crystal structure of the different mineral groups in amphibole could be used to identify them.

The five asbestos types in the amphibole class include amosite, anthophyllite and chrysotile, crocidolite, and actinolite. While the most commonly used form of asbestos is chrysotile; each has its own unique characteristics. Crocidolite is the most dangerous asbestos kind. It contains sharp fibers which are easily inhaled into the lung. Anthophyllite ranges from brown to yellowish in color and is composed of iron and magnesium. This variety was used to make cement and insulation materials.

Amphiboles can be difficult to study because of their complex chemical structure and numerous substitutions. A thorough analysis of the composition of amphibole minerals requires specialized techniques. EDS, WDS and XRD are the most popular methods for identifying amphiboles. However, these methods can only give approximate identifications. For instance, they are unable to distinguish between magnesio-hastingsite from magnesio-hornblende. These techniques also cannot distinguish between ferro-hornblende and pargasite.