 Nanomaterials have been widely used in various industries and applications due to their unique physical and chemical properties. Despite their potential benefits, there have also been concerns about their safety, particularly when it comes to their interaction with living organisms. This paper reviews the main mechanisms behind the toxicity of nanomaterials, including their physical chemical properties, contaminants, surface charge, and free radical generation. Additionally, the authors discuss the in vitro toxicity tests conducted on different types of nanomaterials, such as carbon nanotubes, titanium dioxide nanoparticles, quantum dots, gold nanoparticles, and silver nanoparticles. The results suggest that nanomaterials can cause oxidative stress and cell death, which could lead to serious health risks if not properly controlled. This article was authored by Javad Khalili Fard, Samira Jafari, and Muhammad Ali Abel. We are article.tv, links in the description below.