Inorganic Lead Complexation in Natural Seawater Determined by UV Spectroscopy

Recent effort to construct trace metal complexation models in natural media1–8 is a mark of the importance of chemical form in the biogeochemical behaviour of trace metals. Unfortunately such chemical modelling is difficult in many ways. Chemical speciation models of trace metals in complex natural media such as seawater are usually constructed using stability constants determined in simple media. We describe an alternative procedure which can reduce the errors inherent in this approach. Using UV spectroscopy, we have examined lead speciation in seawater. The method is a means of describing metal speciation in seawater quantitatively using stability constants determined exclusively in seawater. Preliminary experiments indicate that the same approach can be used for other metals including copper