Types of Asbestos and their Associated Risks
Asbestos is a term used to name a number of different fibrous minerals with different properties.
Here you will find the basic differences between the two types and the different risks to human health from breathing in the different fibres.
Commercial use of asbestos has mainly been made using the following fibres:
- Chrysotile (white)
- Amosite (brown)
- Crocidolite (blue)
These three fibres can be split into two distinct groups:
Chrysotile (or white) asbestos is formed of several scrolls and could be said to have a curly, silky nature.
There is increasing evidence that the curly nature helps the human body to remove chrysotile fibres from the lung.
Amphiboles are all other asbestos types.
These fibres are more rod like in nature with the cross section comprising a uniform stacked arrangement of structural units.
Amphiboles are generally straight and stiff, and so are more able to penetrate the lung wall.
It could be said that amphiboles asbestos is more dangerous in one sense, as a proportion of any amphiboles fibres inhaled will never be removed from the human body.
The following forms of amphiboles asbestos were not usually used on their own, but are often contaminants of the commercially used fibres.
Tremolite, Actinolite, Anthophyllite
The three commercially used fibres have very different risk factors associated with them; If chrysotile is given a risk factor of 1, then amosite is likely to have a risk factor of 100 and crocidolite a factor of 200.
The risk factor for tremolite, actinolite and anthophyllite is likely to be similar to that of amosite.
How to know which Type of Asbestos you’re working with
Materials containing crocidolite were last manufactured in the UK in the mid 1960s and most will now have been removed from buildings.
Materials containing amosite were last manufactured in the UK in the late 1970s, and as it was mainly used in asbestos insulating boards which was used for fire protection and insulation, much will still remain in buildings.
Materials containing chrysotile were the most commonly used of all the asbestos containing materials, with the largest percentage being used to make asbestos cement (AC) which was last sold in the UK in 1999 when asbestos containing materials were finally prohibited. A significant amount of AC will still be present in buildings today.
It is still likely that the majority of buildings in the UK contain asbestos containing materials.
Asbestos Related Diseases
Scarring of the lung similar to pneumoconiosis, caused by inhaling large quantities of fibres over a considerable length of time. It is not a disease that is likely to be contracted without extensive exposure to free asbestos fibres over an extended period of time. It can indicate an increased risk of lung cancer or mesothelioma.
A cancer of the lungs, the risk of which will be increased by exposure to large quantities of asbestos. Smoking and exposure to asbestos will markedly increase the risk. It usually takes many years from first exposure to the onset of the disease.
A cancer of the chest lining or pleura, or peritoneum (the lining of the abdominal cavity); exposure to asbestos greatly increases the risk of catching this disease. It usually takes many years from first exposure to the onset of the disease.
(For further information on Mesothelioma, please refer to the MesotheliomaHelpNow website which hosts a range of highly informative, useful and sensitive Mesothelioma related resources).
A thickening of the chest lining or pleura, which can cause shortness of breath and indicates exposure to high quantities of asbestos and might indicate an increased risk of cancers such as lung cancer or mesothelioma. It usually takes many years from first exposure to the onset of the disease.
A thickening in spots of the pleura or chest lining – with time they ossify, but normally they do not cause any symptoms or problems, however they are an indication of asbestos exposure and so may indicate an increased risk of Mesothelioma or lung cancer in the future.