The experimental results of the route of degradation study showed the rapid dissipation to bound residues as main route of degradation of 8-hydroxyquinoline sulphate. Non extractable residues (NER) at 80 d varied between 71.8 and 83.3% AR, associated to a CO2 production of 8.03- 11.04%. At 120 d NER varied between 61% and 79.2% AR and the CO2 production ranged from 9.9 to 11.6%. This behaviour shows the potential of 8-hydroxyquinoline sulphate to form stable chelants. This property is the base of its mode of action as fungicide and bactericide. The rapid dissipation of 8-hydrxyquinoline sulphate to bound residues is reflected in its biphasic behaviour in soil. The best fit was obtained with FOMC and DFOP kinetics. The DT50 values at 20 oC and 40% MWHC were < 1 d in all cases, and DT90 varied between 7.6 h and 34 .3 d.