Researchers have found that nanofibers, just like asbestos, could be dangerous to health and could cause mesothelioma.
This research has been published online in the May 12th issue of the journal of Toxicological Sciences.
Nanofibers are tiny fibrous structures that could be 1,000 times smaller than a human hair. They are found in a large number of applications ranging from airplane wings to biotechnological products.
Researchers worked on mouse models and found that tiny fibers produced by the nanotechnology industry could be similar in shape to asbestos fibers and could result in lung cancers such as mesothelioma.
Prof. Ken Donaldson of respiratory toxicology at the University of Edinburgh, U.K., said: “Concern has been expressed that new kinds of nanofibers being made by nanotechnology industries might pose a risk because they have a similar shape to asbestos.”
Researchers have found that the longer nanofibers are more dangerous to health. Silver nanofibers, which are larger than five micrometers, could accumulate in the lungs and could cause inflammation while many of the smaller fibers moved away from the lungs.
According to Prof. Donaldson, this is the first time that researchers have found the exact length of nanofibers that could cause disease.
You can read the abstract of the paper below;
Suspicion has been raised that high aspect ratio nanoparticles or nanofibres might possess asbestos-like pathogenicity. The pleural space is a specific target for disease in individuals exposed to asbestos and, by implication nanofibres. Pleural effects of fibres depends on fibre length, but the key threshold length beyond which adverse effects occur has never been identified up to now since all asbestos and vitreous fibre samples are heterogeneously distributed in their length. Nanotechnology advantageously allows for highly defined length distribution of synthetically engineered fibres which enable for in depth investigation of this threshold length. We utilised the ability to prepare silver-nanofibres of five defined length classes to demonstrate a threshold fibre length for acute pleural inflammation. Nickel-nanofibres and carbon nanotubes were then used to strengthen the relationship between fibre length and pleural inflammation. A method of intrapleural injection of nanofibres in female C57Bl/6 strain mice was used to deliver the fibre dose and we then assessed the acute pleural inflammatory response. Chestwall sections were examined by light and by scanning electron microscopy to identify areas of lesion; furthermore cell-nanowires interaction on the mesothelial surface of the parietal pleura in vivo, were investigated. Our results showed a clear threshold effect demonstrating that fibres beyond 4 µm in length are pathogenic to the pleura. The identification of the threshold length for nanofibre induced pathogenicity in the pleura has important implications for understanding the structure-toxicity relationship for asbestos-induced mesothelioma and consequent risk assessment with the aim to contribute to the engineering of synthetic nanofibres by the adoption of a benign-by-design approach.
Anja Schinwald, Fiona Murphy, Adriele Prina-Mello, Craig Poland, Fiona Byrne, James Glass, Janet Dickerson, David Schultz, Dania Movia, Chris Jeffree, William MacNee and Ken Donaldson, (2012). The threshold length for fibre-induced acute pleural inflammation: shedding light on the early events in asbestos-induced mesothelioma. Toxicological Sciences, doi: 10.1093/toxsci/kfs171