WASHINGTON — The Food and Drug Administration has a draft guidance document for the use of nanotechnology in food and beverages. The guidance describes the factors manufacturers should consider when determining whether changes in manufacturing processes, including those involving nanotechnology, create a significant change that may: affect the identity of the food substance; affect the safety of the use of the food substance; affect the regulatory status of the use of the food substance; or warrant a regulatory submission to the F.D.A.

The F.D.A. described nanotechnology as an evolving technology that allows scientists to create, explore, and manipulate materials on a scale measured in nanometers — particles so small that they cannot be seen with a regular microscope. The technology has a broad range of potential applications, such as the packaging of food.

“Understanding nanotechnology remains a top F.D.A. priority,” said Margaret Hamburg, F.D.A. commissioner. “F.D.A. is strengthening the scientific tools and methods for evaluating food products, cosmetics, drugs and medical devices. We are taking a prudent scientific approach to assess each product on its own merits and to not make broad, general assumptions about the safety of nanotechnology products.”

The draft guidance encourages manufacturers to consult with the F.D.A. before taking their products that use nanomaterials to market. The F.D.A. said such consultation may help the agency address questions related to the safety or other attributes nanotechnology products.