Carbon nanotubes appear to have a similar cancer causing effect as asbestos in mice
Within days of being injected into mice, the nanotubes — which are increasingly used in electronic components, sporting goods and dozens of other products — triggered a kind of cellular reaction that over a period of years typically leads to mesothelioma, a fatal form of cancer, researchers said.
The preliminary evidence of cancer risk is strong enough to justify urgent follow-up tests and government guidance for nano factory workers. Others called for labels to guide consumers or recyclers who might encounter the material when incinerating or otherwise destroying discarded nano products.
Carbon nanotubes also occur in nature in volcanic ash. It would interesting to see what the cancer effect was of volcanic ash.
There is a lot of media coverage of this study

Brian Wang is a Futurist Thought Leader and a popular Science blogger with 1 million readers per month. His blog Nextbigfuture.com is ranked #1 Science News Blog. It covers many disruptive technology and trends including Space, Robotics, Artificial Intelligence, Medicine, Anti-aging Biotechnology, and Nanotechnology.
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