Sister chromatid exchange from in vitro analysis (SCE) is a cytogenetic method used to control professionally exposed population by means of mutagenic or carcinogenic chemicals. It is the indirect indicator of the level of damage present in the DNA before duplication. The purpose was to determine if the exposure of xylene, methanol and acetic acid poses increased risk of DNA damage. The participants were people younger than 40 who do not work with chemicals or in a radiation zone. The analysis of SCE is based on the 72-hour cultivation of peripheral blood lymphocytes in the nutrient medium in the presence of 5-bromodeoxyuridine (BrdU) and phytohaemagglutinin (PHA). For each chemical, three different concentrations and control are tested. The results demonstrated that the chemicals cause an increase in the number of sister chromatid exchange in relation to the controls. There is a statistically significant reduction of mitotic index (P <0.05) at all concentrations of tested chemicals. This research demonstrates that all of tested chemicals cause an increased number of recombination repair in peripheral lymphocytes and have an antiproliferative effect associated with genotoxicity. Biomonitoring is an important part of health checkups of people occupationally exposed to health hazards. It is based on the measurement of biological indicators which indicate early biological effects that precede the onset of malignancies and other diseases. A routine analysis of SCE may indirectly show the quality of safety measures at a workplace.