Italian scientists suggest that we need a much more detailed toxicological approach to hazard assessment before judgement regarding the long-term safety of carbon nanotubes can be made. They outline their results in the International Journal of Environment and Health.
Although nanotechnology is a relatively new field of research, already there are claims that its products could be harmful to human health and damaging to the environment. In particular, concerns have been raised about the safety of carbon nanotubes, minute hollow fibres of the carbon. Carbon nanotubes are just one group of materials being developed under the umbrella term of nanotechnology, which focuses on materials comprising particles between 1 and 100 nanometres in size. A nanometre is a billionth of a metre.
According to Enrico Bergamaschi of the Department of Clinical Medicine, at the University of Parma Medical School, carbon nanotubes are among the most promising nanomaterials, with potential in engineering, molecular electronics and as drug-delivery agents that could significantly reduce side-effects for countless medications.
In spite of their innovative properties, the small size of carbon nanotubes has led some observers to hypothesize that they may have similar detrimental effects to the sooty particles from vehicle exhausts known as PM10 particulates. Others suggest that toughness and fibrous nature of carbon nanotubes is reminiscent of asbestos fibres and follow the same fibre paradigm.
Bergamaschi and colleagues point out that carbon nanotubes are a recent invention only now finding commercial applications and so clinical and epidemiological evidence for any long-term effects they may have on human health are entirely lacking.
The researchers explain that, despite the occasionally exaggerated headlines seen in the media regarding research studies into the effects of nanotechnology, their novelty means that no one has yet established whether they represent a long-term health risk, or whether they can exacerbate certain pre-existing medical conditions.
"As more of these materials are produced, there is an urgent need to refine strategies to assess their possible effects on employees who represent the main exposed population, along with characterizing exposure, so that appropriate safety regulations can be put in place if needed," says Bergamaschi.