The determination of weakly and strongly bound copper,lead and cadmium in oslofjord samples

Weakly and strongly bound copper, lead and cadmium have been determined in the dissolved and particulate fractions of water samples from Oslofjord. The differentiation was made possible by using different sequences of filtration, acidification and digestion. The quantitative measurements were done by differential pulse anodic stripping voltammetry. Lead was found to be associated mostly with particulate matter, while cadmium was present only in the dissolved fraction. A strong digestion was needed for the determination of total metal. The advantage of pretreating sample bottles and filters with a conditioning solution is illustrated.