Carbon nanotubes are tiny man-made fibers with an incredibly high tensile strength. They are one of the most promising nanotechnological developments with many potential applications in electronics, medicine and futuristic materials. However, a new study by a group of scientists from the US and the UK suggests that carbon nanotubes may cause health problems similar to those of asbestos. The problem comes from their similar shapes: both nanotubes and asbestos consist of hard microscopic fibers that can cause significant damage to the lining of the lungs. The study involved exposing mice to nanotubes and found that nanotubes of a certain size caused asbestos-like inflammations and lesions.
While there are still difficulties in taking full advantage of the exceptional theoretical properties of nanotubes, industry is showing increasing interest. Current applications are limited to products like bicycle handlebars and tennis rackets, where people are prepared to pay a lot for even a very modest strength to weight advantage, but it seems likely that a rapid expansion will take place in the near future. There is thus a second way in which nanotubes might be the new asbestos: they might be pervasive in our materials before the dangers are fully understood.
The potential advantages and disadvantages of nanotubes are both very high. While it might seem foolish to risk our health in exchange for better tennis rackets or handlebars, there are many more important applications which promise to follow within the next decade. We should not block their progress at this stage, but ramp up the safety investigations. People within the nanotech field are unlikely to do sufficient work on health and safety since it often runs directly against their own interests, but researchers in medicine (like the authors of the current study) can take up the challenge. If a series of further studies on the health effects of nanotubes were performed, we could find out more accurate information about the likely danger of inhaled nanotubes in humans and about the chance that nanotubes could escape into the environment from inside the sealed structure of an object like a tennis racket. By performing intensive research now we can prevent nanotubes from being the health time-bomb that asbestos turned out to be.