From Orion Magazine:
The regulation of nanoparticles has been recommended for more than a decade, but there’s no agreement on exactly how to do it. Meanwhile, the lid has already been lifted on nanotechnology. The use of man-made nanoparticles has spread into almost every area of our lives: food, clothing, medicine, shampoo, toothpaste, sunscreen, and thousands of other products. Regulatory structures, both here and abroad, are completely unprepared for this onslaught of nanoproducts, because nanoparticles don’t fit into traditional regulatory categories. Additionally, companies often shield details about them by labeling them “proprietary”; they’re difficult to detect; we don’t have protocols for judging their effects; and we haven’t even developed the right tools for tracking them. If nanotechnology and its uses represent a frontier of sorts, it’s not simply the Wild West—it’s the Chaotic, Undiscovered, Uncontrollable West.
…AS WITH MANY THINGS that are invisible and difficult to understand—think subatomic particles such as the Higgs boson, muons, gluons, or quarks—any discussion of nanoparticles quickly shifts into the realm of metaphor and analogy. People working in nanoscience seem to try to outdo each other with folksy explanations: Looking for a nanoparticle is like looking for a needle in the Grand Canyon when the canyon is filled with straw. If a nanoparticle were the size of a football, an actual football would be the size of New Zealand. A million nanoparticles could squeeze onto the period at the end of this sentence.
But what is a nanoparticle?