Interannual variability of dissolved arsenic (As) and cadmium (Cd) concentrations as well as those in rice grain was investigated in paddy fields subjected to different water managements. While substantial variability was observed in the As and Cd concentrations, unique relationships existed between dissolved and rice grain concentrations across different years and water managements. The results suggest that interannual variability of dissolved As and Cd concentrations was responsible for the variability in the concentrations in rice grain and should be taken into account in risk assessment.