First, please note how kewl "nanotubes" makes anything sound. That is all. Now onto the serious stuff.
Scientists have warned that carbon nanotubes could pose a cancer risk similar to that of asbestos. They say the government should restrict the use of the materials, which are included in a variety of consumer products, to protect human health.
In most products containing nanotubes, such as car body panels, tennis rackets, yacht masts and bike frames, the fibres are embedded in composite materials, which provide strength and lightness. In this form they are likely to be relatively harmless. But the researchers said further studies were necessary to confirm that -- it was not good enough to simply assume that people could not be exposed to carbon nanotubes embedded in materials....
"This is a reason for concern," said Anthony Seaton, a professor and expert in asbestos-related diseases, working at the Institute of Occupational Medicine in Edinburgh. "Asbestos started in the same way -- it had thousands of applications and people used it experimentally. It became very widespread, almost ubiquitous."
The similarity between the size and structure of carbon nanotubes and asbestos fibres has always placed a question mark over how the former could affect lungs. The new research shows that, in mice, the tubes, like abestos, cause inflammation of the mesothelium, the slippery membrane that surrounds lungs and other bodily organs. With asbestos fibres, the inflammation is a stage leading towards the deadly cancer known as mesothelioma. It typically takes 20 to 50 years for the cancer to develop following exposure to asbestos fibres.
The researchers, who report the development in the journal Nature Nanotechnology, compared the effects of short and long nanotubes. With asbestos, stiff fibres about 10 micrometres in length (100 times smaller than a milimetre) are harmless because immune cells can engulf them and safely remove them. Stiff fibres longer than 15-20 micrometres are too big for the cells to handle and their presence provokes an inflammatory response. The researchers confirmed that carbon nanotubes seemed to have the same effect.
Thank god they so efficiently came up with an asbestos replacement. Although there is still some concern of encountering asbestos in older buildings and schools and such, you don't really hear much about it nowadays. I was afraid we'd get off too easy.
Oh, science. Is everything you make deadly?