Even as the pace of nanotechnology research accelerates in labs around the world, a few early studies have raised concerns that tiny man-made particles might pose threats to human health or the environment. While the extraordinary properties of nanoparticles (those smaller than 100 nanometers, the size scale of viruses and even individual molecules) could enable everything from extremely sensitive diagnostic tools to superstrong materials, those same properties might also allow them to penetrate deeper into the lungs, pass more readily through skin, or linger longer in the environment as pollutants-effects that could trigger new regulations.

A collective effort to gather more information is now under way among corporate, academic, and government researchers hoping to get a clearer understanding of whether nanoparticles really do present any dangers. The stakes could hardly be higher. Common items-including some sunscreens and tennis balls-already contain nanoparticles, and some estimates hold that global nanotech-based production will exceed $1 trillion within 15 years. Environmental groups are beginning to warn about potential dangers; the activist organization ETC Group, for one, is actively lobbying for a research moratorium.