The genotoxicity and cytotoxicity were investigated in 40 patients (20 females aged 21.57 +/- 1.42 and 20 males aged 29.35 +/- 3.59) diagnosed at the Emergency Department with organophosphate poisoning. Chromosome aberrations (CAs), sister chromatid exchanges (SCEs), micronucleus (MN), mitotic index (MI), replication index (RI) and nuclear division index (NDI) were evaluated in peripheral bloods of patients. The blood samples were collected from the patients on admission to the emergency department before treatment and after treatment before being discharged from the intensive care unit. The CA, MI and NDI values were increased before the discharge when compared to the levels measured on admission. However, there are no differences in mean SCE, frequency of MN and RI (Tab. 2, Ref. 42).