Under aerobic conditions, the study of De Vette et al. (2001) only enables us to obtain an incomplete route of degradation. 1-NAD degrades in soil forming 1-NAA, a major metabolite (max. of 76.2% of AR after one day). However, this study does not permit to have a complete view on the route of degradation of the metabolites. The fate of 1- NAA is not clearly determined in soil. In addition, it is not possible to conclude on the route of degradation of the naphthalene moiety as no study was conducted with 14C-naphtyl molecule. Despite the fact the study is not validated, the decline of 1-NAD was very rapid (DT90 ~ 2 days) and happened when the mass balance was still fully acceptable for the sandy loam soil. For the humic soil, the DT90 is achieved after 2 days when the mass balance may be already quite poor. However, and for the humic soil, it is considered that these data can be used to determine a kinetic pattern but this will have to be confirmed when new data are available. As a consequence, the DT50 of 1-NAD can be considered as acceptable with a value of 0.058 day for the sandy loam soil and 0.519 day for the humic sandy soil. From the additional report: The route and rate of degradation of 14C-NAD in four soils incubated under aerobic conditions at 20 °C were investigated. 14C-NAD degraded rapidly to in all four soils with DT50 values of 0.39, 0.4, 0.4 and 1.42 days in soils I, II, III and IV, respectively. Besides the parent compound two major metabolites were identified by co-chromatography as 14C- Naphthylacetic acid (M1 (NAA)) and 14C-1-naphthoic acid (M2 (R2)). M1 (NAA) reached maximum amounts of 54.7-73.9% of applied in the four soils. By day 28 it had declined to 2.6% of applied or less for all soils. The DT50 values of M1 were 2.92, 3.14, 2.74 and 2.9 days in soils I, II, III and IV, respectively. M2 (R2) reached maximum amounts of 13.1-22.4% of applied in the four soils. By day 28 it had declined to 2.5% of applied or less for all soils. The DT50 values of M2 were 1.25, 0.99, 2.13 and 0.59 days in soils I, II, III and IV, respectively. High mineralisation of the radioactive residues to radiolabelled carbon dioxide was observed in all soils reaching maximum levels of 65.9%, 68.7%, 52.7% and 62.9% of the applied radioactivity for soils I to IV, respectively, on day 28. The amount of non-extractable radioactivity was also significant, amounting to maximum mean values of 24.3% to 27.9% of the applied radioactivity during the 28-day incubation period. By the end of the study (day 28), the level of bound residues had declined slightly. Organic matter fractionation on day 14 indicated that the majority of the non-extractable radioactivity was bound to the immobile humic acids and humins (18.9-22.4% of the applied radioactivity). Lower amounts of radioactivity (4.6-6.0% of applied) were detected in the more mobile fulvic acid fraction. The main degradation pathway of 1-Naphthylacetamide (1-NAD) in soil proceeds via biodegradation beyond 14C-Napthylacetic acid (NAA) and 14C-1-napthoic acid as the major degradation intermediates and several minor and transient fractions. In addition, a significant 14CO2 production and the formation of bound residues was observed