Toxicity of Nanomaterials-Physicochemical Effects

Nanomaterials are the structures with at least one dimension of <100 nm. Recently, development in nanotechnology has led to use of nanomaterials in many different fields. On other hand, increasing in the use of nanomaterials has led to release of these materials to the environment. Therefore, before employing of these materials in biological and environmental and living systems, they should evaluate in terms of biocompatibility and distribution. Although the toxic effects of nanomaterials on living organisms, human health and the environment have been studied by some researchers, however, there are too much uncertainty about the effects and mechanisms of toxicity of nanomaterials. Therefore, understanding the toxicity effects of nanomaterials is highly desirable. Cellular uptake mechanisms and dispersion of nanomaterials in biological environments depend on their physicochemical properties. Therefore, knowledge the unique characteristics of nanomaterials and the interactions of nanomaterials with biological systems, are important criteria for the safe use of nanomaterials. Properties of nanomaterials such as size, shape, aspect ratio, density, and surface and structural defects and dissolving rate are the main cause of cytotoxicity and side effects of these materials in the body. Exposure to nanomaterials may be cause a range of acute and chronic effects, including inflammation, exacerbation of asthma, metal fume fever, fibrosis, chronic inflammatory diseases and cancer.