Maynard and Aitken call for new methods for measurement of exposure to nanoparticles
New methods and tools for measuring exposure to airborne engineered nanomaterials will be required to protect the health of workers in nanotechnology-related jobs according to Andrew Maynard, chief science advisor at the Woodrow Wilson Center's Project on Emerging Nanotechnologies, and SAFENANO Director Rob Aitken of the IOM.
Their review "Assessing Exposure to Airborne Nanomaterials: Current Abilities and Future Requirements," published in the inaugural issue of the new journal "Nanotoxicology" www.nanotoxicology.net, calls for the development of a novel, inexpensive and versatile aerosol monitor to tackle nanoparticulate exposure measurement issues.
In the paper, Maynard and Aitken develop a classification for nanoparticles into 9 groups, and identify a set of particle attributes thought to be relevant to determining potential health impact for each class. They then assess the effectiveness of current measuring methods for each attribute for each class and provide the information graphically, forming an excellent resource for reference by scientists working to develop monitoring systems for nanoparticles.
Airborne engineered nanomaterials present complex exposure measurement challenges," Maynard said. "Conventional approaches - measuring the mass of airborne material - will not always be sufficient."
Rob Aitken explained "What our analysis shows is that in the complex new 'nano world' there is no single or simple method for monitoring nanoaerosol exposures in order to assess and manage potential health effects. There are instruments that present partial solutions to the measurement challenges we face. But at the end of the day, we lack the tools and devices that are sophisticated, cost-effective and fast enough to do the job.”
They propose a sampling device which would be low cost, and capable of simultaneously measuring aerosol number, surface area and concentration mass of airborne nanoparticulates. However, Aitken and Maynard recognize that "Bringing these technologies together into a single package within the size and cost parameters discussed does present a significant challenge".
This in depth evaluation of the research and development necessary to produce air monitors for nanoparticulates links directly to one of the five grand challenges toward the Safe Handling of Nanotechnology, originally published by Aitken, Maynard and 12 other authors in 'Nature' (Nov 16, 2006).
The paper can be viewed online at http://www.nanotoxicology.net