The control of trace metal concentrations in coastal seawater through partition onto suspended particulate matter

Abstract

The distribution of total metal concentration between dissolved and particulate phases in coastal seawater has been examined as a function of suspended particulate matter (SPM) loading. Partition between dissolved and particulate phases, as defined by a distribution coefficient, is demonstrated to be an important control on the concentration in each phase. The possible impact of anthropogenic inputs on trends in coastal water concentrations are contrasted for waters with a high (Netherlands), and a low (U.K.), SPM loading. For a given increase in input trends will be more readily detected in areas with a slow SPM loading. It is concluded that trends in coastal seawater concentrations will only become apparent after river inputs have dramatically increased. Monitoring coastal water concentrations of dissolved and particulate phase trace metals is not therefore likely to be a sufficiently sensitive technique to detect trends.