The environmental fate of clofentezine was investigated in a number of laboratory studies using either unlabelled or 14C-tetrazine ring labelled material. Results of laboratory aerobic route and rate of degradation studies carried out at 15, 22 or 25°C and either 40 or 50% MWHC were available for 5 soils. One major metabolite (>10%) was identified as 2-chlorobenzoic acid (2- chlorobenzylidene) hydrazide (AE C593600), and was present at a maximum of 13% AR after 30 d. Another metabolite was present at 10.8% AR after 21 d in a clay loam soil, however despite further attempts to identify this unknown metabolite, a structure could not be determined. 3 minor metabolites (<10% AR) were present and identified as follows: N, N’bis (2-chlorobenzoyl) hydrazine (AE C512898), 2-chlorobenzoic acid (AE C500233), 2-chlorobenzamide (AE F092117). Uncharacterised radioactivity was present at a maximum of 18.3 % AR after 7 d in a clay loam soil. At 120 d, CO2 represented 20.1-36.9% AR, and unextracted radioactivity represented 21.0-33.1% AR.