Speciation studies of trace metals in the Gulf of Elefsis, Greece

A method for differentiating trace metal species on the basis of relative lability has been applied for Pb, Cd, Zn, in microenvironments of the Gulf of Elefsis. Species are classified as ''very labile'', ''moderately labile'', ''slowly labile'' and ''inert'' depending on the characteristic time scale of the measuring technique using differential pulse anodic stripping voltammetry (DPASV) and the retention on Chelex-100 resin in successive column and batch procedures. The results show that in two extremely different microenvironments (with S of about 17 parts per thousand and similar to 45 parts per thousand) the slowly labile and inert fractions prevail particularly at the surface layer, whereas in the main water body of the gulf the very labile fraction is the predominant one. However at the thermocline and below it the ''inert'' fraction increases considerably paralleling, broadly, the particulate metal distributions.