This study was conducted to evaluate the possible genotoxic effects of waste anesthetic gases. Comet assay was performed on peripheral blood lymphocytes of 60 volunteers: 20 healthy unexposed office workers and 40 operation room (OR) personnel at Tanta University Hospital (Egypt). The exposed personnel were anesthetists (6 females and 7 males), surgeons (10 males), nurses (9 females), and technicians (8 males). The study revealed significantly increased comet parameters (mean comet tail length and mean percentage of DNA in the tail) in peripheral blood lymphocytes of OR personnel in comparison with control individuals. The maximum DNA damage was observed in anesthesia technicians, whereas the nurses showed the least DNA damage. Furthermore, significant difference was observed between smoker and nonsmokerOR personnel in relation to mean comet tail length. However, no significant difference was seen due to age, gender, or duration of exposure. Also, significant increase in mean percentage of tail DNA was observed in smoker individuals of both exposed and control groups. As a conclusion, this study points to the risk of DNA damage in personnel who are exposed to waste anesthetic gases.