Nano No-No, EPA to Regulate Nanotechnology Pesticides

Nanotechnology manipulates materials at the atomic and molecular levels; they are so tiny they cannot be seen with an ordinary microscope and possess extraordinary mobility and unique chemical and biological properties that increase the potential for biological interaction and toxicity. There are no labeling requirements for nanoscale products.
The EPA has since agreed that nanosilver products intended to kill microorganisms qualify as pesticides, and that developers of such products must now seek EPA review and approval before the products are marketed. The agency has not committed, however, to undertake enforcement actions against currently commercialized products that haven’t undergone the EPA registration process, although it has taken action against some noncompliant manufacturers.
Source: OrganicConsumers.org