The great affinity of Pb for clay and oxyhydroxides of Fe and Al,
as shown in the literature by Ligero et al. (2001), is exhibited by the
connection of Pb to sediments with clay.
Considering the disparity in the results obtained for the different
components, there is a general tendency of decreased concentration
of metallic elements with increasing salinity, as reported in the literature
(Solomons & Forstner, 1984; Mudroch & Duncan 1986).
In the second group, there is similarity between the concentration
of metals evaluated in water and the concentration of metals
evaluated in sediment, which indicates that this variation is
directly related to their sources in the environment.
The metal contamination found in the Canal do Cunha basin and
the western side of Guanabara Bay is alarming, because the bay is
contaminated with high levels of organic materials, the metals
remain in the sediment and do not contaminate the water or reach
the food chain.
4. Conclusions