The U.S. Organic Consumers Association (OCA) has submitted an open letter to the U.S. Food and Drug Administration (FDA) expressing concern that the FDA's current oversight practices do not sufficiently regulate the use of nanomaterials in consumer food, food packaging, and agricultural products, says an association press release.

The letter calls for a moratorium on the manufacture of consumer products containing nanomaterials until the FDA begins reviewing and assessing the safety of products containing nanomaterials and requiring new nano-specific testing and labeling of all products containing nanomaterials.

Unfortunately, it's not that easy defining which foods contain nanomaterlals. In fact, it's not easy defining what nanotechnology is.

For, instance, French researchers have found a
hair dye developed 2,000 years ago relied on nanotechnology to change graying hair into a youthful black color.

"In contrast to modern nanotechnology, the dyeing process is characterized by basic chemistry methods and has been developed more than 2,000 years ago with low-cost natural products," report Philippe Walter and colleagues at the French Museums Restoration Research Center in Paris.

Elsewhere, Richard Jones comments, "I think people would be rightly skeptical if you described making beer as nanotechnology, even though that involves a chemical transformation that's effected by molecularly precise positioning in a nanoscale machine. On the other hand, the use of modified viruses as gene therapy vectors is starting to look very much like nanotechnology. But where, in between, you draw the line, is very difficult to judge."

See Jones' post, "What is this thing called nanotechnology?" In the end, I think the OCA, FDA, or any other organization would have a tough time determining exactly which products to prohibit.