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The word asbestos is a commercial term to indicate any fibrous mineral with a fibrous form. There are two families of asbestos: Chrysotile (white asbestos) and the amphiboles. Except for sharing the same commercial term – asbestos – these two groups have completely different chemical composition, therefore, different effects on the human body.
Throughout the whole world, very few natural or synthetic products cause as much debate as the use of asbestos. The major characteristic of this debate is the years now we alas witness a war, sometimes based on scientific or technical facts but, most of the time; this crusade is attributable to media tactics to support its position which hides commercial interests. Too often, without scientific or technical arguments, the asbestos detractors simply play with people’ emotions.
Since the asbestos debate touches workers and population’s health and security, it is then not unusual to hear about drastic rulings. As an example, let’s think about the actual ruling concerning major stakes of the hour.
Dosage and latency, the forgotten
First, facts are irrefutable: asbestos exploitation – without distinguishing the fibres (Chrysotile and amphiboles) – took its rise in the middle of the 20th century. During this era, protection measures and appropriate work practices for employees, ensuring them a healthy working environment, were practically non-existent. The employees extracting and transforming the fibre, installing and maintaining products containing asbestos were then exposed, for many years, to high dust concentration and this, without appropriate respiratory protection.
Inhaled in great quantity over long period of time, asbestos fibres cumulate in the lungs and exceed the natural capacity of the body to eliminate them. Then follows a gradual diminution of the correct action of the lungs. This phenomenon is called asbestosis. It might eventually provoke lung cancer or mesothelioma – another kind of cancer generally associated with asbestos. However, this process extends over many years (sometimes up to 40 years): this is called the latency period of the disease.
This is, in particular, because of the latency period that it is still possible today to diagnose new cases of disease and this, is in spite of all the improvements concerning the exposure of workers to fibres in the workplace. Alarming reports of the rise of diseases linked to asbestos have triggered intense controversy in Europe, especially in northern countries which, before the 1980s, were heavy users of friable asbestos insulation.
In a nutshell, here is the genesis of the polemic concerning the usage of all kinds of asbestos fibres, including the one that is not an excess of risk to health when it is responsibly used, say Chrysotile.
A little bit of Science
Recent scientific studies have brought to light many nuances and, consequently, the understanding of the mechanism that provoke respiratory diseases after the inhalation of natural or synthetic fibres. These data, then again fundamental, are very often ignored and not included in the debate created by the asbestos detractors.
Today, if one says that one fibre kills, this person is only confirming his great ignorance of recent scientific studies... or has other motivations to say so.
Two fundamental facts… But so often ignored…
The word asbestos is a commercial term to indicate any fibrous mineral with a fibrous form.
There are two families of asbestos: Chrysotile (white asbestos) and the amphiboles.
Except for sharing the same commercial term – asbestos – these two groups have completely different chemical composition, therefore, different effects on the human body.
There is an overwhelming number of published data showing that the mortality experience of workers handling amphiboles is much more severe than that of workers exposed to Chrysotile only.
Moreover, studies confirm that very few cases of mesothelioma have been reliably attributed to Chrysotile – despite past massive and prolonged exposures – but that they are rather linked to exposure to amphibole fibres.
There is more scientific evidence showing that asbestos induced-lung cancer, like asbestosis, is a threshold phenomenon. Low exposures to pure Chrysotile do not present a detectable risk to health. Since total dose over time decides the likelihood of disease occurrence and progression, studies suggest that the risk of an adverse outcome may be low if even any high exposures experienced were of short duration.
To be continued…
(Based on a study published in May 2007 by the Chrysotile Institute, Canada)