With the rapid development of nanotechnology and its applications, a wide variety of nanostructured materials are now used in commodities, pharmaceutics, cosmetics, biomedical products and industries. As the nanocale materials possess novel and unique physicochemical properties than that of bulk materials, they also have unpredictable impact on the human health. What happens with nanomaterials when they enter and interact with a human body, this scientific curiosity is attracting a great attention as well as increasing concern from the public, nanomaterial-based-industries, academia, and the government worldwide. Nanotoxicology is the first textbook in this multidisciplinary area that addresses all those points to fulfill the knowledge gap of the risks from nanotechnology, impact of nanomaterials on the human body, their interactions with biological systems as well as their risk assessments. It consists of 15 review chapters that cover the main aspects dealing with the risk of exposure to nanomaterials. The book summarizes the toxicological effects and biological properties (in vitro or in vivo) for a very wide variety of man-made nanostructured materials including metallic nanoparticles, metal oxide nanoparticles, dendrimers, quantum dots, nanoclusters, nanocrystals, nanowires, fullerenes, fullerene-based derivatives, single- and multi-wall carbon nanotubes, and functionalized carbon nanotubes, polymer nanoparticles, carbon black, nano-coatings, nanomedicines, and other nanomaterials. In addition to the toxicological aspects such as recognition, identification, and quantification of hazards resulting from the human exposure to various types of nanomaterials during manufacturing and applications, this book also outlines possible medical and therapeutic benefits of nanomaterials for clinic diagnosis, drug delivery, and disease treatment, physiological and immunological mechanisms. The book is aimed to provide an up-to-date status of the potential toxicological effects, risk assessment, and safety evaluation of nanostructured materials on the human health, for a wide range of audience working in different areas of nanoscience, nanotechnology industries, biology, toxicology, chemistry, chemical biology, medical sciences, public health sciences, standardization of nanotechnology (nano-safety standards); for policy makers of constituting regulatory frameworks at government departments and nanotechnology industries/enterprises. The book also offers special features that make it useful to the general readers who are interesting in health issues of nanomaterials and safe nanotechnology. Major features that make this book unique and especially useful to readers is the strategies on how to reduce or eliminate nanotoxicological affects and a multidisciplinary methodology for testing all materials on the nanoscale to evaluate the potential for human exposure.