Seasonal variation of aromatic DNA adducts in human lymphocytes and granulocytes.

DNA adducts were measured by 32P-postlabelling in lymphocytes and granulocytes of 75 healthy men exposed occupationally and environmentally to high concentrations of aromatic compounds in the ambient air. Volunteers enrolled in the study were men working at the coke batteries and nonoccupationally exposed inhabitants of Silesia, a highly industrialized region in southern Poland. Blood samples were drawn twice: in February and September 1992. Seasonal variations in the levels of DNA adducts were found only in lymphocytes: 3.6- and 8.7-fold in the occupationally and environmentally exposed groups respectively. In smokers the seasonal variation was as large as 12.8-fold in the environmentally exposed group. No seasonal variations were observed in granulocytes. The observed seasonal variation in the level of aromatic DNA adducts coincided with winter/summer differences in the concentrations of benzo[a]pyrene in the ambient air of Silesia. The study recommends the application of lymphocytes for adduct studies in chronic exposures and provides evidence on the repair of aromatic adducts in lymphocytes.