Degradation of 14C-cadusafos was studied in soils under laboratory conditions in aerobic and anaerobic systems. Three European and three USA soils were tested. No major degradation products/metabolites were identified. Low levels of unidentified metabolites (no single product exceeded 1.7% of the total 14C residue) were detected. Only one metabolite (methyl sec-butyl sulfone), reached the maximum 7.46 % at 14th day and degraded further to 0.06 % by 90th day. This metabolite was formed through oxidation of the S group, which is a common degradation/oxidation mechanism for OPs. The major degradation product is CO2 formed from the carbonyl chain at (max. 70.9% of the applied quantity) and bound residues (max. 33.4% of the applied radioactivity).