The purpose of the current investigation was to examine the relationship between inflammation marker C-reactive protein (CRP), an oxidative stress marker (Malondialdehyde; MDA), and DNA damage assessed by comet assay (single-cell gel electrophoresis, SCG) in smokers and non-smokers. The comet assay score was analyzed by image software using three parameters for measuring DNA damage which were tail length, tail DNA %, and tail moment. SCG is commonly used as an in vitro and in vivo genotoxicity test. Because of its ability to detect different forms of DNA damage and its simplicity of application, the technique is being increasingly used in human biomonitoring. The test was performed on blood samples from smokers and non-smokers to better characterize the comet assay suitability for biomonitoring. A total 123 males who were 21–30 years; they were randomly selected and distributed in three groups (40 non-smokers (consider as controls), 44 narghile-smokers, and 39 cigarette-smokers). The results showed there was a significant increase in both CRP and MDA levels in narghile and cigarette-smokers compared to non-smokers as well as the comet assay results showed augment in DNA damage in both smoker groups compared to non-smokers.
