Nanomaterial health effects--part 1: background and current knowledge.

Nanotechnologies are among the fastest growing areas of scientific research, and have important applications in a wide variety of fields. At the same time, scientists and regulators are concerned about the potential health and environmental risks related to the widespread production and use of the nanomaterials created by these technologies. Several recent animal and cell culture studies have suggested that some engineered nanomaterials may have biological effects similar to ultrafine particulates. This paper describes what nanomaterials are and why they might be toxic, and then reviews existing toxicological studies on engineered nanomaterials.