Rural inhabitants are exposed to considerable amounts of pesticides from water, soil and air. There are indications that exposure to pesticides may trigger production of antinuclearanti bodies (ANA). Therefore, the question arises about the prevalence of ANA in this group. In 90 eastern-Polish rural inhabitants (RI) and 50 urban blood donors (BD), the presence of ANA in serum was tested usingEIA technique (Varelisa ReCombi ANA Profile). The frequency of ANA in the RI group was 2.5-fold higher than in the BD group (p = 0.0175). Among RI, at least one autoantibody was detected in 30 % (95 % CI:20.5-39.5 %). Most frequently, this was anti-dsDNA (12.2 %; 95 %CI: 5.5-19.0 %), followed by SS-A/Ro (7.8 %; 2.2-13.3 %), RNP and Scl-70 (each 5.6 %; 0.8-10.3 %), Jo-1 (3.3 %; 0.0-7.0 %), Sm, SS-B/La, and CENP (each 2.2 %; 0.0-5.3 %). These figures are relatively high compared to studies of other random populations. In the BD group, at least one autoantibody was found in 12 % (95 %CI: 3.0-21.0 %). Most frequently, this was anti-SS-A/Ro (8 %; 95 %CI: 0.5-15.5 %), followed by dsDNA, RNP, and Scl-70 (each 2 %; 0.0-5.9 %).Neither Jo-1, Sm, SS-B/La, nor CENP-autoantibodies were found in this group. These figures place eastern-Polish blood donors in the middle of the range of prevalence observed among blood donors in other countries. The occurrence of antinuclear antibodies in eastern-Polish rural population is relatively high compared to both eastern-Polish blood donors and other random populations. A possible explanation for this is the long-term exposure to pesticides.