What Are the Social Considerations

Chrysotile Versus Amphibole Asbestos Chrysotile and the amphibole asbestos minerals amosite and crocidolite share many physical and chemical properties: fibrous form, high tensile strength, resistance to chemicals and acts as an insulator. However, there are several distinct differences between chrysotile and the forms of amphibole asbestos:
CHRYSOTILE	AMPHIBOLE
Wavy/Curly Fibers	Straight Fibers
More Soluble	Less Soluble
Contain Little Iron	Contains Abundant Iron
Water Clings to Fibers	Fibers Repel Water

These minor physical/chemical differences may result in significant differences in the way that the body interacts with the asbestos fibers...
	Airborne amphibole fibers tend to be smaller may travel deeper into the narrow passageways of the lungs, whereas the longer curly chrysotile fibers would get caught sooner.
	Amphibole fibers tend to be sharper and can penetrate the lung wall easier than chrysotile.
	Amphibole fibers tend to persist in the lung longer than chrysotile fibers because they are less soluble
	Iron-bearing particles react with oxygen in the lung. The products of these reactions then damage the lung, and even the DNA in the cells.
	The longer the fiber, the more chemically reactive it is. Again, the amphiboles tend to be more reactive.
	Our lungs attempt to sweep particles from the walls by carrying them up and out in a mucus flow. Because amphiboles repel water, they are not easily expelled by this natural defense mechanism.
The bottom-line is that amphibole asbestos (crocidolite and amosite) are far more hazardous than chrysotile, particularly in terms of their carcinogenic properties. It is also apparent from medical studies that CROCIDOLITE is more hazardous than AMOSITE which is far more hazardous than CHRYSOTILE.

The Binding of the Asbestos...

To cause health problems the asbestos must be inhaled. Therefore to be hazardous asbestos fibers must break free from the building material that they were in originally. So not only is it the type of asbestos that matters, but the properties of the material that contains the asbestos.

Materials that can be crumbled, and thereby easily release asbestos, are called FRIABLES. These include materials such as plaster, ceiling tiles and most insulation.

Materials that are bound in a sticky or rubbery material (tar, vinyl, etc), and therefore will not easily release contained fibers, are called NON-FRIABLES. These include materials such as floor tiles and roofing shingles.