Bioaccessibility of Trace Metals in Sediment, Macroalga and Antifouling Paint to the Wild Mute Swan, Cygnus olor

The bioaccessibilities of trace metals (Cd, Cr, Cu, Ni, Pb, Zn) in eelgrass, sediment and preparations thereof with and without antifouling paint particles have been assessed by undertaken a physiologically based extraction test (W-PBET) designed to mimic the chemistry of the gizzard and intestine of the mute swan, Cygnus olor. Because Cu- and Zn-based pigments are employed in contemporary antifouling paints, concentrations of these metals were greatest in the preparations containing paint particles. Moreover, relative to total metal, both Cu and Zn displayed the highest gizzard bioaccessibilities in these preparations (about 10%). In the intestine, where most nutrients are absorbed, the accessibility of Cu was maintained while that of Zn was dramatically reduced. These observations were qualitatively consistent with metal concentrations measured in source materials relative to those in swan faeces. We conclude that Cu poses the greatest threat to C. olor inhabiting coastal areas where boat repair takes place.