Once they're in the body, they could . . . well, no one is quite sure what they would do, though plenty of people are concerned about the unknown long-term environmental and health effects of nanoparticles. And while quantum dots are definitely arcane, they have potential applications in quantum computing, cancer treatments and other biomedical research, and next-generation photovoltaic cells. They could some day even be used to create advanced television and computer displays that render colors more accurately than the human eye can detect. In other words, this is the kind of stuff that OSHA has to worry about in the 21st century.