The comet assay, also called the single-cell gel electrophoresis (SCGE) assay, is a rapid and sensitive method for the detection of DNA damage (strand breaks and alkali-labile sites) in individual cells. The assay is based on the embedding of cells in agarose, their lysis in alkaline buffer and finally subjection to an electric current. In the present study, alkaline SCGE was used to evaluate the extent of primary DNA damage and DNA repair in peripheral blood lymphocytes of workers employed in pesticide production. After the period of high pesticide exposure, lymphocytes of the occupationally exposed workers manifested increased tail length and tail moment compared to the control group. After the workers spent 6 months out of the pesticide exposure zone, both endpoints were still above that of the control but significantly decreased as compared to the results of the first analysis.