The Aug. 22, 2012 news item on Nanowerk by way of Feedzilla features some research at the University of Edinburgh which determined that short nanofibres do not have the same effect on lung cells as longer fibres do. From the news item, here’s a description of why this research was undertaken
Nanofibres, which can be made from a range of materials including carbon, are about 1,000 times smaller than the width of a human hair and can reach the lung cavity when inhaled.
This may lead to a cancer known as mesothelioma, which is known to be caused by breathing in asbestos fibres, which are similar to nanofibres.
I wrote about research at Brown University which explained why some fibres get stuck in lung cells in a Sept. 22, 2011 posting titled, Why asbestos and carbon nanotubes are so dangerous to cells. The short answer is: if the tip is rounded, the cell mistakes the fibre for a sphere and, in error, it attempts to absorb it. Here’s some speculation on my part about what the results might mean (from my Sept. 22, 2011 posting),
The whole thing has me wondering about long vs. short carbon nanotubes. Does this mean that short carbon nanotubes can be ingested successfully? If so, at what point does short become too long to ingest?
The University of Edinburgh Aug. 22, 2012 news release provides answer to last year’s speculation about length,
The University study found that lung cells were not affected by short fibres that were less than five-thousandths of a millimetre long.
However, longer fibres can reach the lung cavity, where they become stuck and cause disease.
We knew that long fibres, compared with shorter fibres, could cause tumours but until now we did not know the cut-off length at which this happened. Knowing the length beyond which the tiny fibres can cause disease is important in ensuring that safe fibres are made in the future as well as helping to understand the current risk from asbestos and other fibres, [said] Ken Donaldson, Professor of Respiratory Toxicology.
Sometimes, I surprise myself. I think I’ll take a moment to bask. … Done now!
Here’s my final thought, while this research suggests short length nanofibres won’t cause mesothelioma, this doesn’t rule out other potential problems. So, let’s celebrate this new finding and then get back to investigating nanofibres and their impact on health.