The environmental fate of triazoxide was investigated in laboratory studies using [14Cphenyl]- labelled test substance. Four different soil types were treated at an exaggerated dose and incubated at ca. 20�C under aerobic conditions. One major metabolite (>10% AR) was detected in aerobic conditions; identified as triazoxide-desoxy (M01) which peaked at 12.8% AR after 30 days in silt soil. A second metabolite which was identified as triazoxide-amino (M02), occurred at >4.9% AR in the 4 soils tested and at a peak of 9% AR (10.2% AR in a single replicate) in sand after 3 days. Unidentified degradates were <5.1% AR: Mineralisation to CO2 was low, accounting for <4.5% AR at any sampling interval. Unextracted residues represented a maximum of between 26.7- 29.8% AR in the 4 soils tested with the peak of 29.8% AR occurring in sandy loam after 120 days. The notifier proposed two routes of degradation in soil for triazoxide under aerobic conditions; de-oxygenation of the N-oxide to form the benzotriazine triazoxide-desoxy (M01) and cleavage of the imidazole ring resulting in the amine derivative triazoxideamino (M02).