The rapid growth and development in the synthesis of nanomaterials with carefully controlled properties, such as size and shape, surface area and composition has led to a burgeoning of potential applications for these nanomaterials. However, the toxicological effects of these materials such as nanocrystalline zeolites have not yet been systematically investigated and assessed with respect to their properties. In this proposal, the impact of size, surface chemistry, composition and porosity of nanocrystalline zeolites on the mechanism of death in lung epithelial cells will be investigated.