Chemical speciation of trace metals at the air-sea interface: The application of an equilibrium model

Air-sea interfacial solutions have characteristically high concentrations of trace metals, microorganisms, organic compounds, and solids relative to bulk solutions. The potential for the chemical interaction of an array of trace metals in the interfacial regions with complexing organic ligands and adsorbing solid surfaces has been evaluated through the use of an equilibrium computer model. Computations suggest that higher interfacial accumulations of copper and lead may occur relative to cadmium and mercury. These results are found to be generally compatible with available field data describing trace metal interfacial accumulation. The forms of metals found to be partitioned between bulk and interfacial solutions are consistent with the hypothesis that solid surface adsorption and dissolved organic complexation reactions bring about metal enrichment at the surface microlayer.