Talk:Chrysotile
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[edit] Carcinogenity Dispute
previously the article read:
Chrysotile, a form of asbestos, is a proven human carcinogen (List of IARC Group 1 carcinogens). It is known contributor to mesothelioma. However, unlike other asbestos forms of asbestos such as crocidolite and amosite, Chrysotile only poses a risk when absorbed in extreme quantities. This is due to the fact that Chrysotile is a rolled phyllosilicate, whereas other asbestoform minerals are bladed amphiboles. These blades become imbeded in lung tissue upon inhalation, and serve as a constant irritant until the tissue becomes cancerous. Chrysotile is much more flexible than amphibole asbestos, and does not cause cancer in the same manner. Instead, the risk posed by Chrysotile in large quantities is similar to silicosis caused by inhalation of fine grained quartz. However, EPA and OSHA guidelines do not distiguish between phyllosilicate and amphibole asbestoses.
it was changed to:<br> Chrysotile, a mineral used for asbestos, is not a human carcinogen and no etiology link has been found for chrysotile exposure[1]. Every human and animal study showing asbestos etiology is associated with amphibole fiber asbestos, and there is not a single study showing pure chrysotile etiology. However, some chrysolite ore deposits do contain amphibole fiber asbestos such as tremolite, crocidolite and actinolite. Amphibole asbestos minerals have hard, needle-like fibers that penetrate into the lung tissue by piercing the walls of the alveoli. Since the body cannot dissolve or dispose of the amphibole fibers they cause a scarring of the lungs, called asbestosis, or cause a cancer of the lining (pleura) of the lung, called mesothelioma. Chrysotile fibers, on the other hand, are dissolved or otherwise expelled by the body.
both viewpoints are supported by various authors therefore there is uncertainty—Preceding unsigned comment added by PeanutPower (talk • contribs) 13:56, 16 August 2007
[edit] Manufacturing "uncertainty"
Chrysotile is considered a "Class 1 carcinogen" by the World Health Organisation, the World Trade Organisation, the International Agency for Research on Cancer, the European Union and most other governments around the world. There's a long discussion, for example, of the evaluation process undertaken by the Australian government here, in deciding to impose severe limitations on its use: http://asbestos.vieiratriallaw.com/archives/-asbestos-faqs-australia-severely-restricts-chrysotile.html
There are many documented cases of people dying from mesothelioma (whose only known cause is asbestos exposure) after having contact with only white asbestos (for example the case study in this BBC Radio 4 investigation from 2006: http://www.bbc.co.uk/radio4/youandyours/items/01/2006_42_wed.shtml
The Asbestos industry has put substantial funding into a campaign to convince the world that chrysotile poses "no measurable risk to health". This is spearheaded by the organisation formerly known as the "Asbestos Institute", and now known as the "Chrysotile Institute". This closely mirrors the strategy pursued by the Tobacco Industry in setting up the "Tobacco Institute" in the 1950s to convince the world that the smoking-cancer link was still a matter of scientific controversy. In reality, the overwhelming majority of scientists in the field had concluded from the mid 1950s onwards that the smoking-cancer link was real, just as the overwhelming majority now believe that chrysotile (aka "white asbestos" prior to being rebranded under its chemical name) is harmful to human health.
The fact that a small number of scientists who are paid "consultants" to the asbestos industry say that they disagree with everyone else about the dangers of white asbestos does not make the matter "controversial". A small number of extremists still believe passionately that the earth is flat (see http://theflatearthsociety.org/forum//) but that is no reason for us to consider the case "not proven" or be any less certain that we aren't going to fall off the edge of the world on our next foreign vacation...
A more moderate industry line is to focus on the fact that white asbestos is not quite so harmful as the blue and brown varieties. But given the tens of thousands of deaths caused by those substances, this isn't much of a commendation...
86.139.91.114 08:42, 9 September 2007 (UTC)
[edit] Very few references
It should be easy to find references to back up what is said in the article. The refs given above would be a start.--HughGRex (talk) 11:55, 29 January 2008 (UTC)
- Some refs added, more to come. Physchim62 (talk) 18:03, 31 May 2008 (UTC)