Nanomaterials and their broad implications are rapidly reshaping the landscape of our science and technology. This proposed exploratory research is to address the crucial need of understanding lifeless nanomaterials in biological systems and in the environment. Three objectives are designed to examine the biophysical interactions of single-walled carbon nanotubes (SWNTs), a major class of nanomaterials, and naturally occurring lysophospholipids, and to investigate the toxicity of lipid-solubilized SWNTs in cells and in whole animals. These objectives will be investigated by a synergetic team of researchers who have track records of creativity and productivity and whose expertise encompasses the fields of nanotechnology, biophysics, biology, engineering, and environmental toxicology.