Under aerobic conditions foramsulfuron is quite rapidly degraded in soil, with a half-life between 1 and 20 days. The mineralisation to CO2 was mostly low. The evaluation revealed that the degradation of foramsulfuron predominantly proceeded via loss of the formyl group as a biotically induced hydrolysis step to result into the formation of the major (>10%AR) and predominant metabolite AE F130619. AE F130619 was rapidly degraded with a half-life less than seven days. Additionally, abiotic or biotic hydrolysis at the sulfonyl urea bridge resulted in the formation of AE F092944 as a major metabolite besides AE F153745 and trace amounts of metabolite AE F099095 and AE F148003. The half-life of AE F092944 was widely spread between less than 5 days and up to 250 days. AE F153745 was quite rapidly degraded with a half-life less than four days.