It is known that vegetables can serve as vehicles of food-borne illness when they are grown from seeds contaminated with pathogens. In this study, we investigated the fate of enterohemorrhagic Escherichia coli O157: H7 in experimentally contaminated radish and komatsuna seeds, after long-term storage at 4°C. The bacteria survived for 36 weeks in radish seeds initially contaminated at 10³ cfu/ml, and 20 weeks survival . observed at as low as 10² cfu/ml. On komatsuna seeds, the bacterial count decreased more rapidly . Using scanning immunoelectron microscopy, the bacteria were detected on the surface of sprouts grown from contaminated seeds, and the bacteria were also present inside the stomata . However, heat treatmentat 100°C for 5 sec effectively eliminated the bacteria from the sprouts . These results underscore the possible health risk from contaminated vegetable seeds even after long-term storage at a low temperature, and also the importance of heat treating of harvested vegetables.