The contamination of sediments caused by the deposition of industrial residues from titanium dioxide production, in sand dunes near a wetland was assessed through atomic absorption spectrometry. The contamination occurred near a shallow freshwater wetland called Jau#xE1; Lake, along the coast of Cama#xE7;ari, Bahia, Brazil. Five core samples were collected, including a reference site, from Jau#xE1; Lake and one from a small lake, near the deposition site. Cores were cut in 20-cm sections. Fractions 63 #x3BC;m were analysed for copper, cadmium, zinc, iron, lead, aluminium, mercury and titanium. Metal concentrations on the upper layer of sediments were, as a whole, higher than in lower ones. Concentrations from the reference site were similar to those from the other sites in Jau#xE1; Lake. Absolute values of most metals in the sediments of the Dunas Lake located near the contamination site were higher than in all other stations. The hypothesis, that:: (1) contamination coming from groundwater would contaminate the sediment; and (2) there would be a gradient of decreasing contamination from sites near the residue deposit to sites located further away, were rejected. The continuous removal of groundwater may have contributed to the reduction of further contamination. It is recommended that future studies examine the concentration of metals in plants and the role of plants in metal bioavailability.
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