Today, we continue our series of five weblog installments analyzing nanotechnology and risk, covering both existing and near-future nanoscale technologies as well as medium-future molecular manufacturing.
Part 1 gave an overview of existing nanoscale technologies. Part 2 (today) assesses the risks of nanoscale technology. Part 3 is an overview of molecular manufacturing, and Part 4 addresses the risks of molecular manufacturing. Part 5 will be a conclusion with recommendations.
Part 2: Risks of Nanoscale Technology
Aside from public perception, the main risks in nanoscale technology have to do with nanoparticles. Nanoparticles are very small (1-100 nm) forms of material. At this scale, only a few atoms wide, material properties often change. Unfortunately, some materials become more toxic at small sizes. Some become more mobile in the body or in the environment. Others, of course, become less toxic and less mobile, but the point is that the toxicology of nanoparticles is, so far, largely unpredictable. It should also be noted that nanoparticles come in many kinds. For example, some are thin membranes of self-assembled molecules, while others are small chunks of minerals -- as different from each other as a rock is from a soap bubble.
The existence of nanotechnology as a recognized field has drawn attention to these problems and properties of nanoscale particles. Increased scrutiny should be expected for any technology that makes or uses free nanoparticles. This may even include existing technologies (diesel exhaust, for example, is getting a closer look). Several organizations are starting to look at nanoparticle health issues, including the Center for Biological and Environmental Nanotechnology at Rice University. The UK's Royal Society also recently issued a report on nanoscale technologies, largely focusing on nanoparticle risks.
Many nanotechnologies, of course, do not use free nanoparticles; instead, the nanometer features are bound to a surface or within a volume, or are created chemically. (A few things, including carbon nanotubes, blur the line between particles and chemicals.) But scrutiny, both rational and irrational, may spill over even to non-nanoparticle nanotechnologies.
Opportunistic lawsuits appear to be a risk worth worrying about. Nanotechnology is novel and not well understood by the public, some aspects of it are not easy to explain, and much press has stressed the weirdness of physics at the nanoscale. This may increase the difficulty of getting insurance, a topic that is already being discussed.
It should be noted that the risk level of a nanoscale technology is connected only weakly with its level of innovation. A technology that patterns a surface to achieve a new optical effect may be both very innovative and quite safe. By contrast, a technology that merely grinds a catalyst smaller to increase its activity will produce nanoparticles that may create both physical risks and risks from irrationality.
Tune in tomorrow for Part 3: Molecular Manufacturing Overview.