The present study evaluated the effect of aflatoxin B-1 (AFB(1)) and fumonisin B-1 (FB1) either alone, or in association, on rat primary hepatocyte cultures. Cell viability was assessed by flow cytometry after propidium iodine intercalation. DNA fragmentation and apoptosis were assessed by agarose gel electrophoresis and acridine orange and ethidium bromide staining. At the concentrations of AFB(1) and FB1 used, the toxins did not decrease cell viability, but did induce apoptosis in a concentration and time-dependent manner.