Silver nanoparticles: a brief review of cytotoxicity and genotoxicity of chemically and biogenically synthesized nanoparticles

In recent years interest in silver nanoparticles and their applications has increased mainly because of the important antimicrobial activities of these nanomaterials, allowing their use in several industrial sectors. However, together with these applications, there is increasing concerning related to the biological impacts of the use of silver nanoparticles on a large scale, and the possible risks to the environment and health. In this scenario, some recent studies have been published based on the investigation of potential inflammatory effects and diverse cellular impacts of silver nanoparticles. Another important issue related to nanoparticle toxicity in biological media is the capacity for increased damage to the genetic material, since nanoparticles are able to cross cell membranes and reach the cellular nucleus. In this regard, there is increasing interest in the analysis of potential nanoparticle genotoxicity, including the effects of different nanoparticle sizes and methods of synthesis. However, little is known about the genotoxicity of different silver nanoparticles and their effects on the DNA of organisms; thus further studies in this field are required. This mini-review aims to present and to discuss recent publications related to genotoxicity and the cytotoxicity of silver nanoparticles in order to better understand the possible applications of these nanomaterials in a safe manner. This present work concludes that biogenic silver nanoparticles are generally less cyto/genotoxic in vivo compared with chemically synthesized nanoparticles. Furthermore, human cells were found to have a greater resistance to the toxic effects of silver nanoparticles in comparison with other organisms.