The contribution of electrochemical methodsto the knowledge of dynamic speciation of toxic trace elements in marine waters is critically reviewed. Due to the importanceof dynamic considerations in the interpretation of the electrochemical signal, the principles and recent developments of kinetic features in the interconversion of metal complex species will be presented. As dynamic electrochemicalmethods, only stripping techniques (anodic stripping voltammetry and stripping chronopotentiometry) will be used because they are the most important for thedetermination of trace elements. Competitive ligand ex- change-adsorptive cathodic stripping voltammetry, which should be considered an equilibrium technique rather than a dynamic method, will be also discussed because the complexing parameters may be affected by some kinetic limitations if equilibrium before analysis is not attained and/or the flux of the adsorbed complex is in fluenced by the lability of the natural complexes in the water sample. For a correct data interpretation and system characterization the comparison of results obtained from different techniques seems essential in the articulation of a serious discussion of their meaning.
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