Route of degradation was assessed in four studies in a total of five soils at 20oC in predominantly acid soils, pH range 5.8 – 7.3 (although the soil BBA 2.2 was used in two studies, giving a total of four different soil types). Desamino-metamitron was a major (>10%) soil metabolite in four out of the five soils, occurring at a maximum of 7.5 to 17.1% AR on days 14 to 30. In one soil an unknown metabolite occurred on two consecutive occasions (24h and 48h) at > 5% AR and would therefore trigger further consideration according to the Guidance on Assessing the Relevance of Metabolites in Groundwater (SANCO/221/2000). However the study was conducted in 1994 prior to the implementation of the current guideline and therefore identification of metabolites under 10 % was not required at that time. It is also noted that the levels of the metabolite fell rapidly after 8 d and was not detected at the next sampling point (14 d) or at any time point up to study termination (100d). In 8 other soils no metabolites were observed at levels that would trigger further consideration according to SANCO/221/2000. Overall the RMS considers that due to the relative transient nature of this metabolite, and absence of detection of this metabolite in the other 8 soils tested, no further information would be required. Unidentified radioactivity reached 9.9% in the study by Sneikus (2002), however it was stated that this comprised of up to 5 minor metabolites. Bound residues reached a maximum of 43.5% AR (90 days). The amount of 14CO2 increased over the study period reaching ca 23% at study termination.