A total of 231 weightlifters and powerlifters were asked in an anonymous poll whether they had taken anabolic steroids (AS) for longer than 3 months. A sample of blood was taken from the 17 athletes (7.4%) who answered positively and agreed to cytogenetic analysis of peripheral lymphocytes in order to identify the possible genotoxic risk, and the results were compared with a reference group of 45 blood donors. On the basis of cytogenetic analysis, the increased quantity of chromosome aberrations in peripheral lymphocytes was found to be 2.6% in comparison with the level of 1.3% in a reference group. These results were also verified by the distribution of aberrant cells in cultures of lymphocytes that were analyzed. These results indicated an increased risk of genotoxic exposure of these athletes, which might cause an increase in malignant diseases.