Lab Tests Indicate Inhaled Carbon Nanotubes Pose Cancer Risk

Carbon nanotube illustration (National Science Foundation)

Researchers at University of Edinburgh in Scotland found some types carbon nanotubes could cause cancer if inhaled. Ken Donaldson, a toxicology professor at Edinburgh, and colleagues published their findings in the June 2011 issue of the American Journal of Pathology (paid subscription required).

Carbon nanotubes are a type of nanoscale material (1 nanometer equals 1 billionth of a meter) recently found useful in the production of advanced manufactured materials, hydrogen fuel cells, and medical therapies. Donaldson estimates the global market for manufactured goods with carbon nanotubes exceeding £1 billion ($US 1.62 billion).

The research team deposited shorter and longer carbon nanotubes in the pleural cavity surrounding the lungs of mice. The pleural cavity tissue is the site where asbestos fibers deposit and cause mesothelioma, a form of cancer in that lung-lining tissue.

Donaldson’s team found the response in the lungs to longer carbon nanotubes similar to that of the longer asbestos fibers: acute inflammation leading to progressive fibrosis (scarring) of the lung tissue. Shorter nanotubes, however, were more likely to pass through the lungs and not get caught in the lung tissue.

The findings suggest the length of the nanotubes is a key risk factor with this material that can affect workers or others who may inhale the fibers. The researchers say industry needs to balance these health risks against product needs when determining the optimum length for carbon nanotubes.

Read more: European Nanomaterial Reference Repository Created

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