Death On The Roof

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🔏The most hazardous dust to inhale: asbestos.

One of the upshots of the industrial revolution is the construction of modern houses. One of the useful materials which were found to be very valuable and versatile was asbestos. Asbestos is known for its good insulating properties. It is heat resistant, durable, insoluble in acid, stable in air, and very workable. Indeed it was so  that it was spun into yarn and used to make cloth. This article portrays the science of asbestos and how this remarkable substance amassed an awful reputation.

Asbestos materials are extremely poisonous. They are known to cause devastating diseases. Photo courtesy: istockphoto.


🔏Asbestos has been responsible for thousands of fatalities and contributed to cases of lung cancer.

Asbestos has been recognized since antiquity. Its properties have been described in long past. There is knowledge that it has been used in making items such as earthenware in ancient times.

Aggressive mining of asbestos ensued in the 1800s. Since then asbestos has been an important building material. It was also cheap and versatile.

Although a known hazard, asbestos is still found in many homes especially roofing sheets. Photo courtesy: istockphoto.

🔏What is mesothelioma?⬇️

Today asbestos is coming to be obsolete and there are laws regarding the use of asbestos materials

Chemistry of asbestos

Asbestos belongs to a class of Silicate minerals which vary in hardness. Note it's fibrous appearance. Photo courtesy: istockphoto.


Various substances could be described as asbestos.

They belong to a group of minerals known as Silicates (SiO3²-). There are several kinds of asbestos.

1. Chrysotile: white asbestos of the serpentine group. The formula could be given as Mg3(Si2O5)(OH4)

2. Amphibole: amphiboles are Silicates comparable to serpentine in material properties. In place of magnesium, they could include other elements, especially Iron. This type of asbestos is usually coloured. Examples are brown asbestos (amosite) and blue (crocidolite)

Asbestos resists corrosive action of acids. It is very inert in air and retains it's structure over a large range of temperatures.

Atoms of silicon and oxygen are arranged in complex tetrahedron which is further ordered in sequences leading to lengthy fibrils.

Asbestos has been applied in various ways :

1. Fireproofing objects

2. Thermal and fire insulation

3. Production of asbestos cement

4. Manufacture of roofing sheets

5. Making asbestos filters and papers

Asbestos sheets are relatively less harmful as it's the microparticles that are of serious concern. Nevertheless, the surface contains the dust which is a hazard. Therefore this material must be handled with extreme care. Photo courtesy: istockphoto.


Asbestos is an occupational hazard. Industrial workers and miners have endured devastating health problems during handling and processing the substance.

Physical nature

The mineral is composed of fibres of Silicates. Individual fibres are microscopic and can be easily abraded. It does not exhibit fluorescence and can be examined and characterized using microscopic techniques.

When demolishing asbestos houses, the parts must be dismembered and carefully packaged and disposed to avoid generating the dust. Photo courtesy: istockphoto.


This material displays fibrous fractures. It can easily be shattered into the dust of <1μm length. It is easily dispersible in the air. 

Asbestos is very dangerous to the respiratory system. It is known for causing aggressive lung cancers. Photo courtesy: istockphoto


Asbestos has been ascertained to be carcinogenic. Asbestos severely affects the lungs and associated systems causing breathing crises, scarring of the lungs, Asbestosis, lung cancer and a specific type of malignancy called mesothelioma. Asbestosis is a fibrotic disease which occurs due to intense exposure to asbestos dust. One manifestation of this disease is reduced lung capacity and difficulty breathing. The condition worsens over time.

Mesothelioma: this type cancer is one of the most disastrous types of cancer. One mechanism that provokes this is the interaction between asbestos fibres and DNA during cell division. Small fibres probably destroy DNA by tangling with chromosome strands in a mechanism capable of leading to cancer. Asbestos could furthermore cause lung cancer (different from mesothelioma).

Personnels working with asbestos must follow extreme precautionary measures. Photo courtesy: istockphoto


Asbestos presents danger to public health and is a major concern to people living in mining areas. People who work with the material are at high risk. There is no safe limit on exposure to asbestos dust. Environmental agencies recommend total avoid.

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