Carbon nanotubes found to produce asbestos type symptoms in mice

(Carbon nanotube picture credit: www.bbc.co.uk/news)

Carbon nanotubes – the epitome of the nanotechnology industry – have been found to trigger diseases similar to asbestos in research undertaken on mice including lesions and inflammation.  Use of asbestos triggered a pandemic of lung disease in the 20th Century.

These tiny carbon molecules have remarkable properties that could be used for advanced electronics and materials including medical diagnostics.  They are already known to be incorporated into products such as tennis rackets, bicycle handlebars and baseball bats, where they are used because of their strength and light weight.

In a series of experiments, researchers injected different lengths of multi-walled nanotubes – which comprise two to 50 concentric cylinders – into the abdomen of mice.  Asbestos fibres and tiny flat sheets of carbon were injected into other mice to compare the response.

It was discovered that the long carbon nanotubes were found to be pathogenic. The problem seems to be that cells that usually deal with particles can’t deal with a long, straight shape. 

For example the lung is equipped with a network of cells that engulf foreign particles in a process known as phagocytosis.  These cells can stretch to about 20 microns but beyond 20 microns they start to have trouble enclosing their membrane around a structure.  So they are immobilized, they can’t move properly so they can’t clear material from the lung. They are in a hyperactivated state which leads to inflammation, scarring and probably cancer in the long term.

However, the researchers said the link between long, straight, multi-walled carbon nanotubes and cancers was not proven.

Elaine Warburton   www.geneticsandhealth.com