Based on meanmodel annual concentrations of benzo(a)pyrene in the atmosphere the authors estimated the carcinogenic risk in order to assess its changes in relation to technical provisions made during the period of 1994-1999 within the framework of ecological trends in the Svoboda and Šverma coke plants OKK Ltd. For assessment of the carcinogenic risk they used the method recommended by US EPA. The mean value of individual lifetime risk (ILCR) for 1999 was estimated 2,14 . 10 -4 , for 20001,59 . 10 -5. Bywayof conclusionit maybestatedthat theestimated carcinogenic risk confirms the assumed reduction of the carcinogenic risk for the Ostrava population in 1999 and 2000 after the ecological provisions made in the OKK coke plants.

        Key words: risk comparison - Ostrava coke plants - benzo(a)pyrene - GIS- carci- nogenic risks