Since the 1970s, several toxicological and epidemiological studies have been conducted to assess the respiratory toxicity and pulmonary effects of "ultrafine" (<100 nm) particles versus larger particles . These studies anticipated the advent of nanotoxicology. However, the birth of nanotoxicology can be considered at 2000 th . Several groups recommended frameworks and screening strategies for developing nanomaterials (NMs) that may be used safely, including the International Life Sciences Institute (ILSI), the European Centre for Ecotoxicology and Toxicology of Chemicals (ECETOC), and a collaborative partnership between DuPont Corporation and Environmental Defense .