The significance of coarse sediments in metal pollution studies in the coastal zone

The role of coarse material (sand fraction) in the distribution of metals in polluted marine sediments was investigated in the harbors and the coastal zone of Mytilene, island of Lesvos, Aegean Sea. It was found that sand fraction contains a relatively significant proportion of the anthropogenic metals and therefore it cannot be neglected in metal pollution studies of coastal sediments. Also the distribution of the anthropogenic metals (Cd, Cu, Pb and Zn) in both silt+clay and sand fractions follow the same pattern indicating similar pollution sources. In the bulk sediment (clay + silt + sand fraction) all anthropogenic metals had a significant amount (> 50%) in the acid-extractable (and potentially bio-available) fraction.