The Dangers of Exposure to Asbestos

Asbestos was a component in thousands of commercial products prior to when it was banned. According to research, asbestos exposure can cause cancer, as well as other health problems.

You cannot tell if something includes asbestos by looking at it, and you cannot smell or taste it. Asbestos can only be detected when the substances that contain it are broken, drilled, or chipped.

Chrysotile

At its peak, chrysotile made up for 95% of the asbestos produced. It was used by many industries including construction insulation, fireproofing and insulation. If workers were exposed for long periods to this toxic material, they could contract mesothelioma as well as other asbestos related diseases. Fortunately, the use of this hazardous mineral has declined significantly since mesothelioma awareness began to grow in the 1960's. It is still found in many products we use in the present.

Chrysotile can be used in a safe manner if a thorough safety and handling plan is put in place. It has been discovered that at the current controlled exposure levels, there isn't an danger to the people who handle the substance. Lung fibrosis, lung cancer and mesothelioma have all been found to be strongly linked to breathing airborne respirable fibres. This has been proven for both the intensity (dose) and time of exposure.

One study that looked into the operation of a factory that utilized almost all chrysotile as its friction materials, compared mortality rates in this factory with national mortality rates. The study found that, after 40 years of manufacturing low levels of chrysotile there was no significant increase in mortality at this factory.

Contrary to other types of asbestos, chrysotile fibres tend to be smaller. They can pass through the lungs and enter the bloodstream. They are more likely to cause health issues over longer fibres.

It is extremely difficult for chrysotile fibrous to be a threat to the air or pose any health risk when mixed with cement. The fibre cement products are extensively used across the globe particularly in structures such as schools and hospitals.

Research has demonstrated that amphibole asbestos, like crocidolite or amosite is less likely than chrysotile in causing diseases. Amphibole types like these are the main source of mesothelioma as well as other asbestos-related diseases. When chrysotile is mixed in with cement, it creates a tough, flexible building product that can withstand harsh conditions in the weather and other environmental hazards. It is also easy to clean after use. Professionals can safely dispose of asbestos fibres after they have been removed.

Amosite

Asbestos is a grouping 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 fibres that vary in length, ranging from very thin to broad and straight to curled. These fibers are found in nature in bundles, or as individual fibrils. Asbestos minerals can be found in the form of a powder (talc) or mixed with other minerals and sold as vermiculite and talcum powder and are used in consumer products such as baby powder, face powder and cosmetics.

Asbestos was widely used during the early two-thirds of the 20th century for construction of ships, insulation, fireproofing, and various other construction materials. Most occupational exposures were to asbestos fibres that were borne in the air, but some workers were exposed to toxic talc or vermiculite, and to fragments of asbestos-bearing rock (ATSDR, 2001). Exposures varied from industry industry, era to, and geographical location.

Most asbestos exposures at work were due to inhalation. However, some workers were also exposed via skin contact or through eating contaminated food. Asbestos is now only found in the environment from the natural weathering of mined minerals and deterioration of contaminated products such as insulation, car brakes, clutches as well as ceiling and floor tiles.

It is becoming evident that non-commercial amphibole fibers could also be carcinogenic. These fibers aren't tightly knit like the fibrils found in serpentine and asbestos amphibole, but are instead loose as well as flexible and needle-like. These fibers can be found in the mountains and cliffs of several countries.

Asbestos is absorbed into the environment mostly as airborne particles, but it can also leach into water and soil. This occurs both from natural (weathering and erosion of asbestos-bearing rocks) and human-caused (disintegration and disposal of asbestos-containing wastes at landfill sites) sources. Asbestos contamination of surface and ground water is mostly due to natural weathering, but has also been caused by anthropogenic activities like mining and milling, demolition and dispersal of asbestos-containing materials, and the removal of contaminated dumping soil in landfills (ATSDR 2001). Airborne asbestos fibres are the primary cause of disease among those exposed to asbestos in their job.

Crocidolite

Inhalation exposure is the most popular method of exposure to asbestos fibres. These fibres can enter the lungs, causing serious health problems. Mesothelioma, asbestosis, and other illnesses are all caused by asbestos fibres. Exposure to asbestos fibres can be experienced in other ways, including contact with contaminated clothes or building materials. The dangers of this kind of exposure are higher when crocidolite (the asbestos' blue form, is involved. Crocidolite fibers are thinner and more fragile, making them easier to inhale. They also can get deeper into lung tissue. It has been associated with more mesothelioma cancer cases than other types of asbestos.

The main kinds are chrysotile and amosite. Amosite and chrysotile are the most commonly used forms of asbestos, and comprise 95% of commercial asbestos currently used. The other four asbestos types are not as common, but may still be found in older structures. They are less dangerous than amosite or chrysotile, but they can still pose a threat when combined with other minerals or when mined near other mineral deposits like talc and vermiculite.

Numerous studies have proven that there is a link between stomach cancer and asbestos exposure. However the evidence is not conclusive. Certain researchers have reported an overall SMR (standardized mortality ratio) of 1.5 (95 percent 95% confidence interval: 0.7-3.6) for all workers exposed to asbestos while other studies have reported an SMR of 1.24 (95% of the CI = 0.76-2.5) for those working in chrysotile mines and mills.

The International Agency for Research on Cancer (IARC) has classed all forms of asbestos as carcinogenic. All kinds of asbestos may cause mesothelioma as well as other health issues, however the risks differ based on the amount of exposure people are exposed to, the kind of asbestos involved and the duration of their exposure, and the manner in the way that it is breathed in or consumed. IARC has declared that the best choice for individuals is to stay clear of all forms of asbestos. If you have been exposed to asbestos and suffer from a respiratory disorder or mesothelioma then you should seek advice from your physician or NHS111.

Amphibole

Amphiboles are groups of minerals that may form needle-like or prism-like crystals. They are a type of inosilicate mineral that is composed 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 are composed of (Si,Al)O4 Tetrahedrons which are connected in rings of six. Tetrahedrons can be separated by octahedral strips.

Amphibole minerals can be found in igneous and metamorphic rocks. They are typically dark and hard. They can be difficult to distinguish from pyroxenes because they have similar hardness and colors. They also share a corresponding cleavage pattern. Their chemistry permits a wide range of compositions. The different mineral groups within amphibole are identified by their chemical compositions and crystal structures.

Amphibole asbestos consists of chrysotile, and the five types of asbestos amosite anthophyllite (crocidolite) amosite (actinolite), and amosite. While the most popular form of asbestos is chrysotile, each variety has its own distinct characteristics. Crocidolite is the most dangerous asbestos type. It has sharp fibers that can be easily breathed into the lung. Anthophyllite is brown to yellowish in color and is made up of iron and magnesium. This variety was used to make cement and insulation materials.

Amphiboles are difficult to analyse due to their complex chemical structure and numerous substitutions. Therefore, a detailed analysis of their composition requires specialized methods. EDS, WDS and XRD are the most common methods of identifying amphiboles. These methods can only provide approximate identifications. These techniques, for example cannot differentiate between magnesio-hornblende and hastingsite. In addition, these techniques can not distinguish between ferro-hornblende or pargasite.