The route of degradation of Amitrole under aerobic laboratory conditions was investigated in 3 studies. Two of them (Hawkins et al., 1982a and Scholz et al., 1988) had already been submitted in the original DAR. As explained under B.8.1.1.1, both studies had been accepted although they presented some deviations. An additional study (Hall, 1994), not reported in the original DAR is summarised under B.8.1.1.1.1 and considered acceptable. This study confirms the degradation pathway that had been proposed in the original DAR. Amitrole is rapidly degraded by microbial activity into CO2. Depending on the studies, mineralisation reaches 20-60% AR after 7 days (Hawkins et al., 1982a) or 44.5% AR after 91 days (Hall, 1994). Non extractable residues are also important, reaching 20-50% after 7 days (Hawkins et al., 1982a) or 40.89% AR after 91 days. No major metabolites were quantified. Degradation should proceed via 5-hydroxyaminotriazole rapidly degraded to cyanamide then urea. A secondary pathway leads to urazole. Only urazole, cyanamide, urea and aminoguanidine bicarbonate are found in trace amounts in soil. RMS noted that some unidentified radioactivity reaches levels above 10% on some occasions in the study of Hall (1994). RMS highlights that the HPLC reference standard of 1,2,4-triazole was used in the study, therefore it is not expected that this unknown radioactivity corresponds to 1,2,4-triazole. This should be confirmed by the applicant. The applicant should also clarify whether the unidentified radioactivity is formed by several compounds or not and whether each compound exceeds 5% AR or not. The applicant indicated at the end of December 2012 that this point was currently being checked.