Manganese, copper, zinc, cadmium and lead concentrations were determined in particulate and dissolved phases in the Seine river and its estuary. This site is characterized by macrotidal system, large-scale chemical industrial activities causing contamination of the river system, and by a turbidity maximum in the estuary. Statistical treatment involving principal component analysis of data has shown a marked difference in the behaviour of each metal in solution and suspended material. This phenomenon is related to variations in granulometric profiles, salinity, concentration of different ligands, and amounts of suspended material.... In solution, the behaviour of cadmium and lead is partly related to the gradient of salinity, while that of copper strongly depends on the dissolved organic ligand concentrations. Manganese and zinc are influenced mainly by salinity and the contents of suspended material and thereby by the turbidity maximum, the behaviour of these two metals in solution and particules being similar in the Seine river estuary.