The November 22, 2007 issue of The Economist contains a story on nanotechnology safety entitled "A little risky business." The article focuses on Andrew Maynard’s presentation before the House Science Commitee in October, an event we covered here, and also covers the ongoing debate over the use of silver nanoparticles as an antimicrobial agent in consumer products.
All in all, the Economist article I think provides a useful synopsis of the current dilemma surrounding nanotechnology safety. Its safety discussion begins with a discussion of the distinction between naturally occurring nanoparticles and engineered nanoparticles:
All that sounds alarming, but assessing the risks calls for perspective. Humans are already surrounded by nanoparticles of one sort or another. Much of the food people eat is made of naturally occurring nanoscaled components. Each person breathes in at least 10m nanoparticles a minute. Most of them do no harm.
That said, I am a little disappointed that the article did not sufficiently emphasize the inconclusive nature of the animal studies on nano safety. The article only alludes to studies that show the potential for toxicity:
[s]tudies show there is the potential for such materials to cause pulmonary inflammation; to move from the lungs to other organs; to have surprising biological toxicity; to move from within the skin to the lymphatic system; and possibly to move across cell membranes.
However, we also know that there are a number of studies that suggest that nanomaterials may not have significant toxic effects — see, e.g., Nano Law Report’s coverage of the buckyball study and the study looking at SWNTs in fruit flies.
With all of that said, the article’s bottom line strikes me as reasonable — that we need to do a better job learning what the risks of nanomaterials are so that we can responsibly regulate their use and manufacture and not lose the "baby with the bathwater" in the process.