1 Associate Professor, Department of Chemistry, National and Kapodistrian University of Athens, Greece. Electronic address: ntho@chem.uoa.gr.
2 Department of Environment Chemistry, Eawag: Swiss Federal Institute of Aquatic Science and Technology & Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, Switzerland. Electronic address: Juliane.Hollender@eawag.ch.
3 Associate Professor, Department of Environment, University of the Aegean, Greece. Electronic address: astas@env.aegean.gr.