Carbon nanotubes might be as harmful as asbestos if inhaled, according to a study. A paper in the scientific journal Nature Nanotechnology reports that animal studies indicate that these long and very thin carbon molecules could cause mesothelioma, a cancer previously associated almost exclusively with asbestos exposure.

Craig A Poland and others. Carbon nanotubes introduced into the abdominal cavity of mice show asbestos-like pathogenicity in a pilot study. Nature Nanotechnology Online 20 May 2008. doi:10.1038/nnano.2008.111 [abstract]. The Project on Emerging Nanotechnologies news release. Risks 357.