Some poor science (or at least poor science reporting) from Denmark where Otto Melchior Poulsen of the National Research Centre for the Working Environment (NFA) claims that “We can, on a scientific basis, draw a parallel between the nano boom and the asbestos scandal.”
The scientific basis seems to be “that test animals used for research in his institute on carbon nanotubes got pleural cancer, a disease many workers exposed to asbestos also caught.” The report doesn’t go into any more details, such as whether they were short or long nanotubes or what dose of nanotubes was administered to the animals so we are firmly in Daily Mail territory here.
No one is suggesting that nanomaterials should be squirted around willy-nilly, but putting out this sort of story seems designed to scare rather than inform. Some of the reports that claim to ‘prove’ the dangers of nanotubes have used such huge doses that the animals would have suffocated anyway, and I once met a US scientist who claimed to have data that nanotubes (once more of uncertain type) made rats live for up to 50% longer.
As with all toxicology we are gradually building up a body of knowledge which can be used to reduce risks, but as I often find myself explaining, nanotechnology is rather different to asbestos or even plastics. It’s a set of technologies that was developed when we had both the tools to see what what we were producing, and a huge amount of data about the safety (or otherwise) of materials produced in the twentieth century.
Here’s the difference between nanotubes and asbestos. Pay attention now, it is important.
When the first nanotubes were examined under an electron microscope, researchers wondered if they could cause similar health problems to asbestos fibres. When asbestos was first being used we didn’t have electron microscopes and people thought that radiation and cigarettes were good for you. As a result asbestos was used everywhere, whereas carbon nanotubes are tightly monitored.